Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 04/16/14


AREA FORECAST DISCUSSION
NWS SAN JOAQUIN VALLEY - HANFORD CA
1034 PM PDT SUN APR 13 2014 .UPDATE... SHORT WAVE PUSHING SOUTH THROUGH THE GREAT BASIN TONIGHT WILL CREATE ENHANCED EAST-WEST FLOW ACROSS KERN COUNTY LEADING TO GUSTY WINDS THROUGH THE PASSES AND ALONG THE WEST FACING SLOPES TOWARD SUNRISE. FINE-TUNED THE FORECAST IN THIS AREA FOR THE NEXT 18 HOURS LEANING ON THE HRRR AND NAM DATA WHICH BETTER SUPPORTED THIS SCENARIO. ATTM WIND SPEEDS WILL BE BELOW ADVISORY CRITERIA THOUGH WE/LL MONITOR THROUGH THE NIGHT. THE PERIOD OF STRONGEST WINDS SHOULD BE RELATIVELY SHORT AND LAST ABOUT 3-5 HOURS. WARM-UP STILL LOOKS GOOD FOR TOMORROW WITH REGIONAL SOUNDINGS DEPICTING A DESCENDING AND DESICCATING AIRMASS COMING IN AND MODEL CONSENSUS REMAINS STEADY. && .SYNOPSIS... WARM AND DRY TEMPERATURES WILL CONTINUE INTO THE WORK WEEK AS HIGH PRESSURE PREVAILS OVER THE FORECAST AREA FOR THE NEXT SEVERAL DAYS. && .PREV DISC... /ISSUED 125 PM PDT SUN APR 13 2014/ DISCUSSION... THE WINDS ALOFT ARE FORECAST TO TURN OFFSHORE OVERNIGHT...AND SOME DOWNSLOPING THROUGH THE PASSES OF THE KERN COUNTY MOUNTAINS IS EXPECTED MONDAY. THIS WOULD ERODE THE MARINE AIR OVER THE SOUTH END OF THE VALLEY AND ALLOW FOR SOME WARMING...EVEN IF THE REMAINDER OF THE SAN JOAQUIN VALLEY REMAINS COOL. ABOVE THE MARINE AIR POOL...EXPECT HIGH TEMPERATURES TO BE AS CURRENTLY FORECAST WITH THE UPPER-LEVEL RIDGE OVER THE REGION. THE UPPER-LEVEL SHORT-WAVE THAT DROPPED INTO THE GREAT BASIN OVERNIGHT AND BROUGHT THE GUSTY WINDS TO THE KERN COUNTY MOUNTAINS AND SOUTHEASTERN KERN DESERT WAS MOVING INTO UTAH AND ARIZONA THIS AFTERNOON. 500-MB HEIGHTS WILL INCREASE OVER THE NEXT 24 HOURS... WITH THE 5760-METER HEIGHT LINE AS FAR NORTH AS SACRAMENTO AND RENO. ANOTHER SHORT-WAVE IS FORECAST TO MOVE INTO THE PACIFIC NORTHWEST MONDAY NIGHT BUT THE MODELS NO LONGER FORECAST THE WAVE TO WEAKEN THE RIDGE. RATHER...THE SHORT-WAVE IS FORECAST TO RIDE OVER THE RIDGE AND DROP INTO THE GREAT BASIN TUESDAY...PUSHING THE RIDGE OFFSHORE. THE SHORT-WAVE ALSO WILL BRING ANOTHER ROUND OF GUSTY WINDS TO THE KERN COUNTY MOUNTAINS AND DESERTS TUESDAY AFTERNOON THROUGH WEDNESDAY MORNING...WITH ADVISORY-LEVEL WINDS POSSIBLE. THE UPPER-LEVEL RIDGE IS FORECAST TO BUILD BACK INTO THE STATE THURSDAY...ALTHOUGH BOTH THE GFS AND ECMWF DEVELOP A SPLIT FLOW WITH THE NORTHERN BRANCH PUSHING INTO THE PACIFIC NORTHWEST AND NORTHERN CALIFORNIA AND THE SOUTH BRANCH MAINLY INTO NORTHERN MEXICO. AN UPPER-LEVEL SHORT-WAVE IS FORECAST TO MOVE INTO THE PACIFIC NORTHWEST THURSDAY NIGHT...FLATTENING THE NORTH BRANCH AND PUSHING THE SOUTHERN BRANCH FURTHER SOUTHWARD. THE ECMWF IS DEEPER WITH THIS SHORT-WAVE BUT BOTH MODELS DEVELOP A CLOSED LOW WEST OF SAN DIEGO WHICH MOVES INTO SOUTHERN CALIFORNIA FRIDAY. BEYOND FRIDAY THE GFS AND ECMWF CONTINUE THEIR TREND OF DIVERGENT SOLUTIONS FOR THE WEEKEND FORECAST. CONFIDENCE IN EITHER SOLUTION REMAINS LOW AT THIS TIME...SO WILL LEAVE THE DAY 6-7 FORECAST UNCHANGED FOR NOW. && .AVIATION... VFR CONDITIONS WILL PREVAIL ACROSS THE CENTRAL CA INTERIOR THROUGH THE NEXT 24 HOURS. && .AIR QUALITY ISSUES... NONE. && .CERTAINTY... THE LEVEL OF CERTAINTY FOR DAYS 1 AND 2 IS HIGH. THE LEVEL OF CERTAINTY FOR DAYS 3 THROUGH 7 IS HIGH. THIS INFORMATION IS PROVIDED AS PART OF A TRIAL PROJECT CONDUCTED BY THE NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD. CERTAINTY LEVELS INCLUDE LOW...MEDIUM...AND HIGH. PLEASE VISIT WWW.WEATHER.GOV/HNX/CERTAINTY.PHP /ALL LOWER CASE/ FOR ADDITIONAL INFORMATION AND/OR TO PROVIDE FEEDBACK. && .CLIMATE... RECORDS SITE DATE HI_MAX:YEAR LO_MAX:YEAR HI_MIN:YEAR LO_MIN:YEAR KFAT 04-13 97:1898 54:1998 59:1936 34:1911 KFAT 04-14 98:1985 52:1956 60:1985 36:1972 KFAT 04-15 96:1947 57:1988 62:1925 35:1970 KBFL 04-13 94:2008 57:2012 59:1930 32:1893 KBFL 04-14 99:1985 56:2003 62:1962 33:1893 KBFL 04-15 97:1994 57:2007 61:1947 36:1921 && .HNX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ PUBLIC...INIGUEZ AVN/FW...BSO SYNOPSIS...WP WEATHER.GOV/HANFORD
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1002 AM MDT MON APR 14 2014 .UPDATE... ISSUED AT 1002 AM MDT MON APR 14 2014 CURRENT FORECAST TRENDS STILL ON TRACK. STORM SYSTEM HAS PUSHED EAST AND SOUTHEAST OF THE AREA. STILL SOME LINGERING SNOW SHOWERS ALONG THE CONTINENTAL DIVIDE OF SUMMIT AND GRAND COUNTIES AND ALONG THE PARK AND GORE RANGES OF WESTERN JACKSON COUNTY AS NOTED BY WEB CAMS. AS DRIER AND MORE SUBSIDENT AIR SPREADS INTO THE REGION THIS MORNING...THESE LIGHT SHOWERS SHOULD BE COMING TO AN END. NORTHERLY FLOW ALOFT BECOMES MORE NORTHWEST DURING THE AFTERNOON AS UPPER TROUGH MOVES INTO THE CENTRAL PLAINS AND UPPER RIDGE BUILDS INTO THE GREAT BASIN. LATEST RAP INDICATING A WEAK MID LEVEL SHORTWAVE MOVING ACROSS NEBRASKA DURING THE AFTERNOON. THERE IS SOME WEAK ASCENT ASSOCIATED WITH THIS WAVE...LOOKS TO REMAIN NORTHEAST OF COLORADO. BOTH THE RAP AND HRRR INDICATE SURFACE CAPE VALUES OF 100 J/KG FAR ACROSS LOGAN...SEDGWICK AND PHILLIPS COUNTIES BY 21Z. THERE IS ALSO SOME CIN AS WELL. NOT EXPECTING ANY SHOWERS WITH THIS WAVE...PERHAPS A BIT MORE MID LEVEL CLOUD FAR NORTHEAST CORNER. COOLER AIRMASS TO BE OVER THE AREA TODAY...HIGHS IN THE 40S ACROSS NORTHEAST PLAINS STILL LOOKING GOOD. MAY NEED TO LOWER THE HIGHS ACROSS ZONE 36 AND 41 AS THIS AREA RECEIVED DECENT SNOW. && .SHORT TERM...(TODAY THROUGH TONIGHT ) ISSUED AT 344 AM MDT MON APR 14 2014 THE STORM SYSTEM THAT BROUGHT THE COLD AND SNOW WILL CONTINUE TO MOVE OFF TO THE EAST THIS MORNING. LIGHT SNOW WILL TAPER OFF DURING THE EARLY MORNING HOURS FROM WEST TO EAST. THE LIGHT SNOW COULD LINGER INTO THE MID MORNING OVER THE EASTERN PLAINS. DRIER MOVING IN BEHIND THIS SYSTEM WILL BRING MOSTLY SUNNY SKIES BY AFTERNOON. NORTHERLY FLOW ALOFT AND AT THE SURFACE WILL PREVAIL BEHIND THE EXITING SYSTEM TODAY. THIS WILL RESULT IN COOL TEMPERATURES WITH HIGHS AROUND 40 DEGREES OVER NORTHEAST COLORADO. WARMER AIR ALOFT WILL START TO MOVE OVER COLORADO TONIGHT...HOWEVER LOWS WILL BE BELOW NORMAL FOR THIS TIME OF YEAR. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 344 AM MDT MON APR 14 2014 ON TUESDAY IT WILL BE WARMER...A RIDGE OF HIGH PRESSURE ACCOMPANIED BY A DRY NORTHWESTERLY FLOW ALOFT WILL BE OVER NERN CO. THE FLOW ALOFT TRANSITIONS TO MORE OF A WESTERLY FLOW BY 00Z WEDNESDAY AS THE NEXT SYSTEM APPROACHES THE STATE FM THE NORTHERN ROCKIES. TUESDAY NIGHT...MOISTURE WILL INCREASE OVER THE MOUNTAINS AS THE NEXT UPPER TROUGH CONTINUES TO APPROACH NRN CO. THIS SYSTEM WILL NOT BE AS WELL ORGANIZED AS THE ONE OVER THE WEEKEND BUT COULD STILL SPREAD A FAIR AMOUNT OF LIGHT TO MODERATE PCPN OVER THE REGION. AFTER 06Z WEDNESDAY...THE MDLS GENERATE SOME QPF IN THE MOUNTAINS NORTH OF INTERSTATE 70. BY 12Z WEDNESDAY...A WEAK UPPER TROUGH AXIS BRUSHES ACROSS NERN CO...WITH A COLD FRONT MOVING INTO THE NERN CO LATE WEDNESDAY MORNING AND AFTN. NOT MUCH PCPN INITIALLY BUT A FAIRLY GUSTY WINDS ACROSS THE NERN PLAINS ACCOMPANYING THE COLD FRONT. SHALLOW UPSLOPE WILL DEVELOP ALONG THE FRONT RANGE BY 00Z THURSDAY FOLLOWING THE PASSAGE OF THE COLD FRONT. WEAK QG ASCENT AT THE SFC AND ALOFT...STRONGEST FM 06Z TO 18Z THURSDAY AS THE MAIN AXIS ASSOCIATED WITH THE UPPER TROUGH MOVES ACROSS NRN CO. BY THE AFTN...DECREASING QG ASCENT WILL DEVELOP ALOFT BUT SHALLOW ANTICYCLONIC UPSLOPE WILL ALLOW FOR CHANCE OF PRECIPITATION TO LINGER INTO THURSDAY EVENING. THURSDAY NIGHT INTO FRIDAY...A DRY AND SUBSIDENT NORTHWESTERLY FLOW ALOFT WILL BE OVER CO AHEAD OF ANOTHER RIDGE OF HIGH PRESSURE. AS A RESULT...DRY AND WARMER CONDITIONS WILL RETURN FRIDAY. OVER THE WEEKEND...A WEAK UPPER TROUGH WILL APPROACH COLORADO FM THE DESERT SOUTHWEST WITH A CHANCE OF RAIN/SNOW DEVELOPING IN THE MOUNTAINS IN THE AFTN...WITH A SLIGHT CHANCE OF RAIN POSSIBLY SPREADING INTO THE NERN PLAINS SATURDAY NIGHT INTO SUNDAY. TEMPERATURES ARE PROGGED TO REMAIN MILD OVER THE WEEKEND. && .AVIATION...(FOR THE TAFS THROUGH 00Z TUESDAY AFTERNOON) ISSUED AT 1002 AM MDT MON APR 14 2014 WINDS TRYING TO SHIFT TO THE NORTHWEST ACROSS THE AREA AIRPORTS...STILL MORE WESTERLY AT KDEN AND KAPA. SHOULD BECOME MORE NORTHWEST WITHIN THE NEXT HALF HOUR...THOUGH...AS NORTHWEST FLOW JUST OFF THE SURFACE MIXES DOWN WITH HELP FROM SUBSIDENCE. WILL CONTINUE THE TREND OF CURRENT TAFS FOR THE UPCOMING 18Z ISSUANCE...WITH WINDS GRADUALLY SHIFTING CLOCKWISE TO THE NORTHEAST THEN SOUTHEAST DURING THE AFTERNOON...BEFORE GOING TO DRAINAGE THIS EVENING. VFR TO CONTINUE WITH UNLIMITED CEILINGS. THERE MAY BE A BIT MORE MID LEVEL CLOUD LATER THIS AFTERNOON WITH A PASSING MID LEVEL WAVE...APPEARS THIS WILL REMAIN WELL NORTHEAST OF DENVER. SOUTHERLY WINDS TO PREVAIL TUESDAY...MAY BE A BIT MORE SOUTHEAST AT KDEN AND KAPA BY THE AFTERNOON. && .BOU WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...D-L SHORT TERM...MEIER LONG TERM...COOPER AVIATION...D-L
AREA FORECAST DISCUSSION
NWS ALBANY NY
145 AM EDT MON APR 14 2014 .SYNOPSIS... HIGH PRESSURE OFFSHORE WILL CONTINUE TO USHER IN A SOUTH TO SOUTHWEST WIND OVER OUR REGION THROUGH MONDAY WITH UNSEASONABLY WARM TEMPERATURES. A STRONG COLD FRONT WILL SLOWLY CROSS THE REGION TUESDAY WITH SHOWERS...SOME OF WHICH COULD BE HEAVY...AND BRING A RETURN TO COLDER WEATHER ON WEDNESDAY. HIGH PRESSURE WILL BUILD IN THURSDAY THROUGH THE END OF THE WEEK WITH DRY WEATHER EXPECTED. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... AS OF 1245 AM EDT...RADARS INDICATED THAT ALL THE SHOWER ACTIVITY HAS EXITED OUR ADIRONDACK REGION. THE MESO-SCALE HRRR MODEL INDICATE NO FURTHER ADDITIONAL SHOWERS ARE EXPECTED. SINCE THERE WAS NOTHING UPSTREAM...REMOVED ANY MENTION OF SHOWERS FROM THAT AREA. A WEAK FRONTAL BOUNDARY NEVERTHELESS BROUGHT SOME SHALLOW COOL AIR DOWN INTO ADIRONDACKS. DURING THE PAST HOUR THE WIND AT BURLINGTON SHIFTED BACK TO THE SOUTH (WHERE IT HAS BEEN NORTHERLY). WE BELIEVE THE FRONT HAS RUN OUT OF STEAM AND SHOULD LIFT NORTHWARD...OR AT THE VERY LEAST...DISSIPATE. MOST OF THE REGION WILL HAVE A DRY AND MILD NIGHT. SO FAR...NO REAL SIGN OF STRATUS DEVELOPMENT...ALTHOUGH THE TEMPERATURE AND DEWPOINTS WERE COMING CLOSE IN VALUE ACROSS LONG ISLAND. SOME FOG OR STRATUS COULD FORM IN THE NEXT COUPLE OF HOURS. SO...VERY LITTLE TO TINKER WITH FOR THIS UPDATE. JUST SOME VERY MINOR RE-TOOLING OF THE GRIDS. WAS TEMPTED TO RAISE OVERNIGHT LOWS EVEN MORE (THE PREVIOUS SHIFT ALREADY DID THAT). HOWEVER...WE SEE WHERE SOME SPOTS IN THE MOHAWK VALLEY HAVE DECOUPLE AND COOLED OFF. EVEN AT ALBANY...THE WIND HAS DIMINISHED (BUT STILL A BREEZE STILL THERE). WITH A MAINLY CLEAR SKY...TEMPERATURES COULD STILL DROP A BIT MORE TOWARD DAYBREAK. EVEN SO...WE ARE LOOKING AT AN INCREDIBLY MILD OVERNIGHT FOR THE TIME OF YEAR. LOOK FOR LOWS MAINLY IN THE 50S...WITH SOME UPPER 40S ACROSS THE NORTHERN AREAS...LOCALLY UPPER 50S IN THE CAPITAL REGION. THIS WOULD MAKE APRIL 14TH THE MILDEST NIGHT IN THE RECORD BOOKS. THE MILDEST OVERNIGHT LOW IS 55 SET BACK IN 1941. AS LONG AS WE DO NOT GET THAT LOW AND STAY ABOVE THAT VALUE THROUGH MIDNIGHT TONIGHT...WE WILL HAVE A NEW RECORD WARM MINIMUM TEMPERATURE FOR APRIL 14TH. && .SHORT TERM /6 AM THIS MORNING THROUGH WEDNESDAY/... ANY LOW CLOUDS IN THE REGION SHOULD MIX OUT THROUGH THE MORNING DUE TO THE STRONG BOUNDARY LAYER FLOW...BUT SINCE IT IS SOUTHERLY FLOW...IT MAY TAKE MOST OF THE MORNING TO BREAK UP...WHICH COULD SHAVE A DEGREE OR TWO OFF THE POTENTIAL HIGH TEMPERATURES TOMORROW AFTERNOON. BASED ON UPSTREAM CONDITIONS IN THE OH VALLEY...EVEN WITH QUITE A BIT OF MID AND HIGH CLOUDS AROUND...TEMPERATURES STILL WELL INTO THE 70S TO NEAR 80...AND SUSPECT MANY AREAS OF CENTRAL AND EASTERN NY WILL SEE TEMPERATURES MONDAY TO THOSE LEVELS...WITH A LITTLE COOLER IN HIGHER ELEVATIONS AND PERHAPS NW CT THROUGH THE BERKSHIRES AND SOUTHERN VT WHERE SOME UPSLOPE CLOUDS COULD LIMIT THE SUNSHINE A BIT. THERE COULD BE SOME ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS TOMORROW AFTERNOON...ESPECIALLY IN WESTERN AREAS BUT NO REAL ORGANIZED FOCUS TO TRIGGER OR SUPPORT MUCH SHOWER OR THUNDERSTORM ACTIVITY. MONDAY NIGHT AND TUESDAY...INCREASING COVERAGE OF SHOWERS AND SCATTERED THUNDERSTORMS WITH LOWS MONDAY NIGHT IN THE 50S. THERE ARE SOME INDICATIONS OF WEAK INSTABILITY ALONG AND AHEAD OF THE COLD FRONT BUT EVEN WITH CONVECTION ROOTED IN THE BOUNDARY LAYER...WITH SUCH STRONG BOUNDARY LAYER WINDS OVER THE REGION... SOME STRONG WIND GUSTS COULD MIX DOWN IN ANY CONVECTION LATE MONDAY NIGHT AND TUESDAY...EVEN IF THERE MAYBE LITTLE TO NO THUNDER. LOCALLY HEAVY RAIN SHOULD OCCUR AS WELL SINCE FORCING SHOULD BE QUITE EXTREME WITH A VERY UNUSUAL EXTREMELY TIGHT THERMAL GRADIENT ALONG WITH CONSIDERABLY ABOVE NORMAL PRECIPITABLE WATER ANOMALIES. TIMING OF THE PASSAGE OF THE COLD FRONT LOOKS TO BE THROUGH THE DAY TUESDAY...SO AFTER HIGHS IN THE 50S AND 60S...TEMPERATURES SHOULD FALL THROUGH THE AFTERNOON. THERE IS A DECENT CONSENSUS FOR PRECIPITATION ENDING AS SNOW SHOWER ACTIVITY TUESDAY NIGHT... WITH SOME LIGHT ACCUMULATIONS IN HIGHER ELEVATIONS. LOW TEMPERATURES WEDNESDAY MORNING IN THE 20S TO NEAR 30. DRYING AND CLEARING TRENDS OCCUR WEDNESDAY WITH HIGHS IN THE 40S TO NEAR 50...SOME 30S SOUTHERN ADIRONDACKS. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... THE LONG TERM PERIOD WILL BE CHARACTERIZED BY SEASONABLE TEMPERATURES AND MAINLY DRY WEATHER...WITH THE POSSIBILITY OF A STORM SYSTEM AFFECTING THE REGION FOR THE WEEKEND. AT THE START OF THE LONG TERM PERIOD...THE EXTENSION OF A HIGH PRESSURE RIDGE WILL BE IN PLACE ACROSS THE REGION WEDNESDAY NIGHT...WITH SOUTHWESTERLY LOW-LEVEL RETURN FLOW HELPING TO MODERATE TEMPERATURES BACK TOWARDS SEASONABLE LEVELS. LOWS WEDNESDAY NIGHT HOWEVER WILL BE COLD...IN THE LOW 20S TO AROUND 30. THE INFLUENCE OF THE HIGH PRESSURE RIDGE WILL ALLOW FOR DRY WEATHER ACROSS THE REGION TO END THE WORK WEEK WITH PARTLY CLOUDY SKIES. HIGH TEMPERATURES THURSDAY WILL WARM BACK INTO THE UPPER 40S TO MID 50S WITH LOWS THURSDAY NIGHT GENERALLY IN THE UPPER 20S TO MID 30S. WITH A CONTINUED LOW-LEVEL SOUTHWESTERLY FLOW...HIGHS FRIDAY WILL BE A LITTLE WARMER THAN THURSDAY...WELL INTO THE 50S AND PERHAPS EVEN THE LOW 60S IN THE HUDSON RIVER VALLEY DEPENDING ULTIMATELY ON HOW MUCH DAYTIME BOUNDARY LAYER MIXING OCCURS. LOWS FRIDAY NIGHT WILL BE IN THE 30S. LONG RANGE GUIDANCE BEGINS TO DIVERGE BY THE WEEKEND HANDLING THE EVOLUTION OF A LOW PRESSURE SYSTEM ORIGINATING ACROSS THE CENTRAL PLAINS. HAVE INTRODUCED CHANCE POPS INTO THE FORECAST FOR MUCH OF THE WEEKEND FOR A PERIOD OF RAIN SHOWERS. WILL HAVE TO MONITOR EXACTLY HOW MUCH PRECIPITATION ACCOMPANIES THIS SYSTEM AS THERE ARE HINTS THAT IT MAY TAP SOME GULF MOISTURE. HIGHS DURING THE WEEKEND WILL BE IN THE 50S TO LOW 60S WITH LOWS IN THE MID 30S TO LOW 40S. && .AVIATION /06Z MONDAY THROUGH FRIDAY/... MAINLY VFR CONDITIONS WILL CONTINUE AT THE KALB/KGFL/KPOU/KPSF TAF SITES FOR THE FIRST 18 TO 20 HOURS OF THE TAF PERIOD (15/00Z-02Z)... WITH MAINLY MID/HIGH CLOUDS OCCURRING DURING THIS PERIOD. MODELS DO SUGGEST THE POTENTIAL FOR SOME STRATUS TO DEVELOP EARLY MONDAY MORNING AS THE SOUTHERLY FLOW CONTINUES. HOWEVER...OBSERVATION AND STLT PICS DO NOT SHOW ANY STRATUS AS OF 0530Z...SO WILL ONLY INCLUDE THE POSSIBILITY OF MVFR CIGS AND VSBYS AT THE TAF SITES AS A TEMPO GROUP BETWEEN 14/10Z AND 14/14Z. LATE IN THE PERIOD...AFTER 15/02Z...MVFR AND EVEN IFR STRATUS IS MORE LIKELY TO DEVELOP AT THE TAF SITES AS THE STRONG SOUTHERLY FLOW CONTINUES AND THE COLD FRONT MOVES INTO WESTERN NY. SOUTH WINDS WILL AVERAGE 5-10 KT OVERNIGHT...EXCEPT 10-12 KT AT KALB AND KPSF WITH GUSTS UP TO 20S KTS. SOUTH WINDS WILL INCREASE BY LATE MONDAY MORNING INTO THE 12-18 KT RANGE...WITH GUSTS OF 25 TO 30 KTS AT KALB/KPSF...AND 20 TO 25 KTS AT KGFL/KPOU. THE STRONG WINDS WILL CONTINUE INTO MONDAY NIGHT AND DIMINISH TO GUSTS OF AROUND 15KTS AT KGFL/KPOU/KPSF...BUT GUSTS UP TO 25 KTS WILL CONTINUE AT KALB. OUTLOOK... LATE MONDAY NIGHT: HIGH OPERATIONAL IMPACT.BREEZY DEFINITE SHRA...TSRA. TUESDAY: HIGH OPERATIONAL IMPACT.WINDY WITH GUSTS TO 34.0. SHRA...TSRA LIKELY. TUESDAY NIGHT: MODERATE OPERATIONAL IMPACT.BREEZY LIKELY SHRA...SHSN. WEDNESDAY: NO OPERATIONAL IMPACT. NO SIG WX. WEDNESDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. THURSDAY: NO OPERATIONAL IMPACT. NO SIG WX. THURSDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. FRIDAY: NO OPERATIONAL IMPACT. NO SIG WX. && .FIRE WEATHER... SOUTH WINDS 10 TO 20 MPH WITH GUSTS TO 30 MPH TOMORROW... HIGH PRESSURE OFFSHORE WILL SUPPORT WARM SOUTH TO SOUTHWEST WINDS OVER OUR REGION THROUGH MONDAY WITH UNSEASONABLY WARM TEMPERATURES. A STRONG COLD FRONT WILL SLOWLY CROSS THE REGION TUESDAY WITH SHOWERS...SOME OF WHICH COULD BE HEAVY...AND BRING A RETURN TO COLDER WEATHER ON WEDNESDAY. HIGH PRESSURE WILL BUILD IN THURSDAY THROUGH THE END OF THE WEEK WITH DRY WEATHER EXPECTED. MOST OF THE MOHAWK VALLEY AND CATSKILLS ARE NOW SNOW FREE...WHILE SNOW COVER STILL LINGERS ACROSS THE NORTHERN BERKSHIRES...LAKE GEORGE AREA...THE SOUTHERN GREEN MOUNTAINS AND OF COURSE THE ADIRONDACKS. A SOUTHERLY BREEZE WILL LIKELY PERSIST TONIGHT IN MANY AREAS... ESPECIALLY THE CAPITAL REGION...MOHAWK VALLEY AND HIGHER TERRAIN. THIS WILL PREVENT A FULL RECOVERY. MONDAY WILL BE A WARM MAINLY DRY DAY WITH PARTIAL SUNSHINE AND THE CONTINUED SOUTHERLY BREEZE AGAIN AVERAGING 10 TO 20 MPH...BUT GUSTING UP TO OR EVEN A LITTLE OVER 30 MPH AT TIMES. RH VALUES LOOK TO BE BOTTOMING OUT IN THE 40 TO 50 PERCENT RANGE. A SLOW MOVING COLD FRONT SHOULD BRING A SOAKING RAIN TO THE REGION MONDAY NIGHT AND TUESDAY...FOLLOWED BY MUCH COLDER WEATHER TUESDAY NIGHT INTO WEDNESDAY. && .HYDROLOGY... A FLOOD WARNING REMAINS IN EFFECT FOR THE DELTA DAM ON THE UPPER MOHAWK RIVER UNTIL FURTHER NOTICE...AS RECENT RAINFALL AND SIGNIFICANT SNOW MELT IS EXPECTED TO KEEP THE RESERVOIR ABOVE FLOOD STAGE FOR THE NEXT FEW DAYS. A RIVER FLOOD WARNING HAS ALSO BEEN ISSUED FOR RIVERBANK DUE TO EXPECTED SNOW MELT AND RESULTANT RIVER RISES INTO THE BEGINNING OF THE WEEK. OTHER RIVERS IN AND THE ADIRONDACKS...SOUTHERN GREENS...AND BERKSHIRES WILL SEE MINOR DIURNAL RISES DUE TO SNOW MELT. THE ONLY AREAS WHERE SIGNIFICANT RIVER ICE REMAINS ARE THE UPPER HUDSON RIVER AND EAST CANADA CREEK. AT THIS TIME NO SIGNIFICANT ICE JAMS HAVE BEEN REPORTED...AND FLOODING IS NOT ANTICIPATED AT THIS TIME. WARM TEMPERATURES THROUGH TUESDAY WILL CAUSE MORE RAPID SNOWMELT IN THE ADIRONDACKS/LAKE GEORGE AREA AND SOUTHERN VERMONT... RESULTING IN MORE RUNOFF AND RISES ON RIVERS AND STREAMS. TEMPERATURES TONIGHT AND MONDAY NIGHT LOOK TO REMAIN WELL ABOVE FREEZING...SO THE MELT AND RUNOFF WILL CONTINUE UNCHECKED. THEN...A SLOW MOVING COLD FRONT WILL LIKELY BRING MORE SIGNIFICANT RAINFALL MONDAY NIGHT INTO TUESDAY. AT THE VERY LEAST...THIS RAIN ALONG WITH INITIALLY THE WARM TEMPERATURES...WILL LIKELY RESULT IN SIGNIFICANT WITHIN BANK RISES ON MANY RIVERS AND STREAMS. IN OUR NORTHERN AREAS...THE COMBINATION OF RAIN AND SNOW MELT COULD EVEN RESULT IN MINOR TO PERHAPS EVEN SOME MAJOR FLOODING ON SOME RIVERS AND STREAMS. ONCE THERE IS BETTER AGREEMENT AS TO THE DEGREE OF SNOW MELT AND RAINFALL AMOUNTS THROUGH TUESDAY...FLOOD WATCHES MAY NEED TO BE ISSUED MONDAY IF CONFIDENCE IN WIDESPREAD HIGH IMPACT FLOODING INCREASES. IT IS ADVISABLE TO STAY TUNED FOR FURTHER UPDATES. FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. MA...NONE. VT...NONE. && $$ SYNOPSIS...NAS NEAR TERM...HWJIV SHORT TERM...NAS LONG TERM...IRL AVIATION...GJM FIRE WEATHER...NAS HYDROLOGY...HWJIV/NAS
AREA FORECAST DISCUSSION
NWS MIAMI FL
126 PM EDT MON APR 14 2014 .AVIATION... VFR CONDITIONS WILL PREVAIL THROUGH THE FORECAST. IT DOES NOT APPEAR TO BE A REPEAT PERFORMANCE OF IFR CIGS/VSBY AT APF TONIGHT AS MIXING SHOULD BE TOO STRONG AND MID LEVEL CLOUDS WILL BE ON THE INCREASE. THE OTHER CONCERN WILL BE MOISTURE INCREASE/INSTABILITY ON TUESDAY AS A COLD FRONT MOVES INTO CENTRAL FLORIDA. CURRENT THINKING IS THAT ANY CONVECTION WILL BE TOO ISOLATED AND TOO LATE IN THE FORECAST TO MENTION AT THIS TIME WITH THE MAIN THREAT AFT 18Z. KOB && .PREV DISCUSSION... /ISSUED 949 AM EDT MON APR 14 2014/ UPDATE... A PERSISTENT GROUP OF SHOWERS WILL CONTINUE ACROSS THE LOCAL ATLANTIC WATERS THIS MORNING. THE INTERACTION OF THE SOUTH- SOUTHWESTERLY LAND BREEZE AND THE MEAN EASTERLY FLOW COULD HELP IN THE DEVELOPMENT OF BRIEF WATERSPOUTS WITHIN THIS ACTIVITY. THIS RISK WILL DECREASE RAPIDLY AS THE LAND BREEZE WEAKENS WITH THE TEMPERATURE RISING LATE THIS MORNING. LATEST HRRR SHOWS SHOWERS DEVELOPING THIS AFTERNOON AND EVENING ACROSS THE INTERIOR AND WEST DUE TO THE INTERACTION OF EASTERLY FLOW AND THE WEST COAST SEA BREEZE. TEMPERATURES ARE EXPECTED TO REACH THE LOW 90S ACROSS THAT AREA ALSO #ISMELLSUMMER. PREV DISCUSSION... /ISSUED 745 AM EDT MON APR 14 2014/ AVIATION... MOSTLY VFR CONDITIONS ARE EXPECTED ACROSS SOUTH FLORIDA WITH THE EXCEPTION OF PERIODIC MVFR CIGS ALONG THE EAST COAST EARLY IN THE FORECAST AS A FEW SHOWERS MOVE IN FROM THE ATLANTIC, ESPECIALLY FROM FLL TO PBI. ALSO, IFR CONDITIONS DEVELOPED OVER THE FAR WESTERN PENINSULA AND ADVECTED OVER THE APF TERMINAL FIELD. THIS SHOULD BEGIN TO LIFT OUT AFT 13-14Z. SURFACE WIND IS LIGHT E-SE AND THIS WILL INCREASE TO 10-12KT AFT 14-15Z WITH A SEA BREEZE DEVELOPING AT APF AROUND 16-17Z. KOB PREV DISCUSSION... /ISSUED 241 AM EDT MON APR 14 2014/ UNSETTLED WEATHER IS EXPECTED THIS WEEK OVER SOUTH FLORIDA... SHORT TERM... HIGH PRESSURE WILL CONTINUE TO MOVE FURTHER EAST INTO THE ATLANTIC WATERS THROUGH TUESDAY ALLOWING FOR A COLD FRONT OVER THE CENTRAL UNITED STATES TO MOVE SOUTHEAST INTO NORTH FLORIDA. THIS WILL ALLOW FOR THE WIND FLOW TO SWING FROM AN EASTERLY DIRECTION TODAY TO A SOUTHERLY DIRECTION ON TUESDAY OVER SOUTH FLORIDA ALLOWING FOR MOISTURE TO WORK INTO THE AREA LATE TONIGHT INTO TUESDAY. THEREFORE...THE WEATHER SHOULD REMAIN DRY TODAY INTO TONIGHT OVER MOST OF SOUTH FLORIDA. THE ONLY EXCEPTION TO THIS IS OVER THE LAKE OKEECHOBEE REGION AND PALM BEACH COUNTY TODAY WHERE A FEW SHOWERS COULD DEVELOP DUE TO THE SEA BREEZE AND LAKE BREEZE COLLISION...AND ALONG THE EAST COAST METRO AREAS TONIGHT. ON TUESDAY...THERE WILL BE A CHANCE OF SHOWERS OVER MOST OF SOUTH FLORIDA WITH EVEN SOME THUNDERSTORMS OVER SOUTH FLORIDA. THE COLD FRONT WILL CONTINUE TO MOVE SOUTHWARD AND THROUGH SOUTH FLORIDA TUESDAY NIGHT BRINGING IN SOME DRIER WEATHER. THE DRY WEATHER WILL NOT LAST LONG...AS THE FRONT WILL COME BACK NORTHWARD LATE WEDNESDAY AFTERNOON INTO WEDNESDAY NIGHT AS A WARM FRONT. SO THE WEATHER OVER SOUTH FLORIDA FOR TUESDAY NIGHT WILL BE DRY WITH ISOLATED TO SCATTERED SHOWERS FOR WEDNESDAY INTO WEDNESDAY NIGHT. LONG TERM... THE FRONT WILL CONTINUE TO MOVE NORTHWARD INTO CENTRAL FLORIDA LATE THIS WEEK...AS WEAK LOW PRESSURE DEVELOPS ALONG THE FRONT IN THE GULF OF MEXICO AND MOVES ACROSS NORTH FLORIDA. THIS WILL ALLOW FOR MOISTURE TO REMAIN OVER SOUTH FLORIDA LATE THIS WEEK WITH A CHANCE OF SHOWERS AND EVEN A FEW THUNDERSTORMS. THE LOW WILL CONTINUE TO MOVE NORTHEAST INTO THE MID ATLANTIC STATES...AS THE FRONT REMAINS NEARLY STATIONARY OVER NORTH FLORIDA. THIS WILL KEEP THE LOW LEVEL MOISTURE IN PLACE OVER SOUTH FLORIDA THIS WEEKEND ALLOWING FOR ISOLATED TO SCATTERED SHOWERS OVER SOUTH FLORIDA. MARINE... THE EASTERLY WINDS TODAY WILL SWING SLOWLY TO A SOUTHERLY DIRECTION BY TUESDAY...BEFORE GOING NORTHERLY ON WEDNESDAY. THE WIND SPEEDS WILL BE 15 KNOTS OR LESS TODAY THROUGH WEDNESDAY. THIS WILL KEEP THE SEAS BELOW 7 FEET IN BOTH THE ATLANTIC AND GULF WATERS THROUGH WEDNESDAY. && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$
AREA FORECAST DISCUSSION
NWS MIAMI FL
949 AM EDT MON APR 14 2014 .UPDATE... A PERSISTENT GROUP OF SHOWERS WILL CONTINUE ACROSS THE LOCAL ATLANTIC WATERS THIS MORNING. THE INTERACTION OF THE SOUTH- SOUTHWESTERLY LAND BREEZE AND THE MEAN EASTERLY FLOW COULD HELP IN THE DEVELOPMENT OF BRIEF WATERSPOUTS WITHIN THIS ACTIVITY. THIS RISK WILL DECREASE RAPIDLY AS THE LAND BREEZE WEAKENS WITH THE TEMPERATURE RISING LATE THIS MORNING. LATEST HRRR SHOWS SHOWERS DEVELOPING THIS AFTERNOON AND EVENING ACROSS THE INTERIOR AND WEST DUE TO THE INTERACTION OF EASTERLY FLOW AND THE WEST COAST SEA BREEZE. TEMPERATURES ARE EXPECTED TO REACH THE LOW 90S ACROSS THAT AREA ALSO #ISMELLSUMMER. && .PREV DISCUSSION... /ISSUED 745 AM EDT MON APR 14 2014/ AVIATION... MOSTLY VFR CONDITIONS ARE EXPECTED ACROSS SOUTH FLORIDA WITH THE EXCEPTION OF PERIODIC MVFR CIGS ALONG THE EAST COAST EARLY IN THE FORECAST AS A FEW SHOWERS MOVE IN FROM THE ATLANTIC, ESPECIALLY FROM FLL TO PBI. ALSO, IFR CONDITIONS DEVELOPED OVER THE FAR WESTERN PENINSULA AND ADVECTED OVER THE APF TERMINAL FIELD. THIS SHOULD BEGIN TO LIFT OUT AFT 13-14Z. SURFACE WIND IS LIGHT E-SE AND THIS WILL INCREASE TO 10-12KT AFT 14-15Z WITH A SEA BREEZE DEVELOPING AT APF AROUND 16-17Z. KOB PREV DISCUSSION... /ISSUED 241 AM EDT MON APR 14 2014/ .UNSETTLED WEATHER IS EXPECTED THIS WEEK OVER SOUTH FLORIDA... SHORT TERM... HIGH PRESSURE WILL CONTINUE TO MOVE FURTHER EAST INTO THE ATLANTIC WATERS THROUGH TUESDAY ALLOWING FOR A COLD FRONT OVER THE CENTRAL UNITED STATES TO MOVE SOUTHEAST INTO NORTH FLORIDA. THIS WILL ALLOW FOR THE WIND FLOW TO SWING FROM AN EASTERLY DIRECTION TODAY TO A SOUTHERLY DIRECTION ON TUESDAY OVER SOUTH FLORIDA ALLOWING FOR MOISTURE TO WORK INTO THE AREA LATE TONIGHT INTO TUESDAY. THEREFORE...THE WEATHER SHOULD REMAIN DRY TODAY INTO TONIGHT OVER MOST OF SOUTH FLORIDA. THE ONLY EXCEPTION TO THIS IS OVER THE LAKE OKEECHOBEE REGION AND PALM BEACH COUNTY TODAY WHERE A FEW SHOWERS COULD DEVELOP DUE TO THE SEA BREEZE AND LAKE BREEZE COLLISION...AND ALONG THE EAST COAST METRO AREAS TONIGHT. ON TUESDAY...THERE WILL BE A CHANCE OF SHOWERS OVER MOST OF SOUTH FLORIDA WITH EVEN SOME THUNDERSTORMS OVER SOUTH FLORIDA. THE COLD FRONT WILL CONTINUE TO MOVE SOUTHWARD AND THROUGH SOUTH FLORIDA TUESDAY NIGHT BRINGING IN SOME DRIER WEATHER. THE DRY WEATHER WILL NOT LAST LONG...AS THE FRONT WILL COME BACK NORTHWARD LATE WEDNESDAY AFTERNOON INTO WEDNESDAY NIGHT AS A WARM FRONT. SO THE WEATHER OVER SOUTH FLORIDA FOR TUESDAY NIGHT WILL BE DRY WITH ISOLATED TO SCATTERED SHOWERS FOR WEDNESDAY INTO WEDNESDAY NIGHT. LONG TERM... THE FRONT WILL CONTINUE TO MOVE NORTHWARD INTO CENTRAL FLORIDA LATE THIS WEEK...AS WEAK LOW PRESSURE DEVELOPS ALONG THE FRONT IN THE GULF OF MEXICO AND MOVES ACROSS NORTH FLORIDA. THIS WILL ALLOW FOR MOISTURE TO REMAIN OVER SOUTH FLORIDA LATE THIS WEEK WITH A CHANCE OF SHOWERS AND EVEN A FEW THUNDERSTORMS. THE LOW WILL CONTINUE TO MOVE NORTHEAST INTO THE MID ATLANTIC STATES...AS THE FRONT REMAINS NEARLY STATIONARY OVER NORTH FLORIDA. THIS WILL KEEP THE LOW LEVEL MOISTURE IN PLACE OVER SOUTH FLORIDA THIS WEEKEND ALLOWING FOR ISOLATED TO SCATTERED SHOWERS OVER SOUTH FLORIDA. MARINE... THE EASTERLY WINDS TODAY WILL SWING SLOWLY TO A SOUTHERLY DIRECTION BY TUESDAY...BEFORE GOING NORTHERLY ON WEDNESDAY. THE WIND SPEEDS WILL BE 15 KNOTS OR LESS TODAY THROUGH WEDNESDAY. THIS WILL KEEP THE SEAS BELOW 7 FEET IN BOTH THE ATLANTIC AND GULF WATERS THROUGH WEDNESDAY. && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 86 74 89 66 / 20 10 50 30 FORT LAUDERDALE 87 75 88 69 / 20 10 30 30 MIAMI 87 75 88 70 / 10 10 30 30 NAPLES 87 72 84 67 / 10 10 40 20 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$ SHORT TERM...30/KOB LONG TERM....17/ERA
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
255 PM CDT MON APR 14 2014 .DISCUSSION... 1205 PM CDT CHALLENGING FORECAST CONTINUES THROUGH THE EVENING WITH PRECIP COVERAGE...INTENSITY...AND TYPE BEING THE MAIN FOCUS. LARGE SCALE UPPER TROUGH COVERING THE MID SECTION OF THE COUNTRY CONTINUES TO PIVOT EASTWARD PUSHING COLDER AIR INTO THE REGION. SUBTLE WAVES TRAVERSING THE FLOW CONTINUE TO WORK WITH COLD ADVECTION TO BRING PRECIP DEVELOPMENT. SURFACE TEMPS HAVE WARMED CENTRAL AND SOUTHEAST WHICH IS SUPPORTIVE OF MORE RAIN BUT TEMPERATURES WILL LIKELY COOL INTO THE AFTERNOON FROM THE NORTHWEST. THEREFORE...PRECIP TYPE THROUGH EARLY AFTERNOON WILL LIKELY BE RAIN OR SNOW EXCEPT FOR FAR SOUTHEAST AREAS THAT WOULD SEE RAIN...THOUGH PRECIP CHANCES ARE LOWER THERE. WATER VAPOR SHOWS A MORE ORGANIZED SHORTWAVE STARTING TO EJECT NORTHEAST FROM SOUTHWEST MISSOURI AND EASTERN OKLAHOMA AND KANSAS. THIS WAVE WILL LIFT INTO THE AREA LATE THIS AFTERNOON INTO THE EARLY EVENING AND TIGHTEN THE MID LEVEL BAROCLINIC ZONE RESULTING IN INTENSIFYING FRONTOGENESIS. RADAR MOSAIC SHOWS BANDS OF PRECIP DEVELOPING NORTHEASTWARD IN CONJUNCTION WITH THIS FEATURE. WILL CONTINUE WITH THE IDEA OF A MORE FOCUSED PERIOD OF PRECIPITATION LATE THIS AFTERNOON INTO THE EVENING BUT HAVE TRIED TO REFINE DETAILS. WHILE PRECIP WILL CONTINUE ON AND OFF THROUGH THE AFTERNOON...HAVE SLOWED THE PERIOD OF BETTER COVERAGE/INTENSITY SLIGHTLY. FORECAST SOUNDINGS/CONCEPTUAL MODELS SUPPORT ALL SNOW WITHIN THE MOST INTENSE BAND THANKS TO WELL ALIGNED ASCENT WITHIN THE SNOW GROWTH ZONE AND COOLING LOW LEVEL TEMP PROFILES. EXPECT THAT THERE WILL BE A CORRIDOR OF MODERATE SNOW WITHIN A LARGER AREA OF LESS INTENSE PRECIP THAT WILL DEVELOP NORTHWARD ALONG A LINE FROM ROUGHLY CHICAGO TO MENDOTA...THEN PIVOT EASTWARD INTO THE EVENING. MUCH OF THE EVENING RUSH HOUR IN THE CHICAGO METRO LOOKS TO FALL INTO THE PERIOD OF MORE INTENSE SNOWFALL...WHICH MAY LAST A FEW HOURS. THE VORT MAX LIFTS NORTHEAST WHICH MAY BRING A LULL IN THE PRECIP EARLY THIS EVENING BUT LARGER SCALE FORCING INCREASES TO THE EAST SO THERE MAY BE RE-INTENSIFICATION OVER NORTHWEST INDIANA BY MID EVENING BEFORE PRECIP EXITS LATE EVENING. TEMPERATURES WILL LIKELY COOL INTO THE MID 30S LATER TODAY AND SNOW SHOULD FALL AT AN INTENSE ENOUGH RATE TO PROVIDE FOR ACCUMULATION ON GRASSY SURFACES AND SLUSHY ACCUMULATION ON ROADS. WILL CONTINUE WITH THE IDEA OF AROUND AN INCH OF ACCUMULATION. MDB //PREV DISCUSSION... 330 AM CDT THE INFAMOUS WINTER 2013-2014 BEGAN IN OCTOBER WITH SNOW AND TODAY IT WANTS TO MAKE SURE IT INCLUDES APRIL TO ENCOMPASS SEVEN MONTHS. THIS UNFRIENDLY VERY LATE VISIT FROM WINTER WAS THE PRIMARY FORECAST CHALLENGE...ALONG WITH TEMPERATURES THROUGHOUT THE WEEK AS WE WILL BE WELL BELOW NORMAL TO START THIS WEEK...POTENTIALLY TO RECORD LEVELS TONIGHT. THIS MORNING... THE 995MB SURFACE LOW IS PASSING OVER THE NORTH METRO OF CHICAGO EARLY THIS MORNING AND 30 MILES EITHER SIDE OF ITS PATH SEPARATES 60S AND CONVECTIVE RAIN SHOWERS AND 30S AND DEFORMATION SNOW. THE DEEPENING AND CLASSIC LOOKING UPPER WAVE WITH THIS IS ADVANCING NORTHEAST FROM SOUTHWEST WI AND ITS DEFORMATION AND WRAPAROUND MOISTURE WILL ONLY GRAZE THE AREA THIS MORNING. WHILE A MIX WITH WET SNOW IS PROBABLE OVER PARTS OF NORTH CENTRAL IL...THE FORCING FOR MODEST SNOW RATES IS LIKELY TO REMAIN TO THE NORTH IN THE A.M. HOURS SO NOT EXPECTING ANY ACCUMULATIONS PRIOR TO NOON. WINDS ON THE BACKSIDE OF THE LOW THIS MORNING LOOK TO GUST TO AROUND 40 MPH AT TIMES...WHICH BESIDES ADDING QUITE A CHILL TO THE AIR...MAY REDUCE VISIBILITY UP BY ROCKFORD IF SNOW CAN MATERIALIZE THIS MORNING. OTHERWISE THOUGH...IMPACTS LOOK MINOR DURING THIS PERIOD. THIS AFTERNOON AND TONIGHT... A SECOND WELL-DEFINED UPPER CIRCULATION IS ADVANCING EASTWARD INTO THE CENTRAL PLAINS EARLY THIS MORNING. THIS IS BASICALLY ROUNDING THE BASE OF WHAT REALLY IS A MASSIVE LONGWAVE TROUGH ACROSS CENTRAL NORTH AMERICA...WITH AN IMPRESSIVE JANUARY-LIKE -40C OBSERVED AT 500MB LAST NIGHT ALL THE WAY SOUTH TO CYQD IN SOUTHERN MANITOBA. GIVEN THE UPPER FLOW...PV ANOMALY EVOLUTION...AND MID-LEVEL BAROCLINICITY...THIS WAVE IS FORECAST TO TURN MORE NORTHEAST THIS AFTERNOON AND ADVANCE INTO CENTRAL AND NORTHERN IL/IN DURING THE MID-AFTERNOON INTO MID-EVE. THIS WILL BRING WITH IT FOCUSED OMEGA AND FRONTOGENETIC SUPPORTED UPWARD MOTION DURING THAT PERIOD AND WOULD EXPECT TO SEE MODERATE PRECIPITATION DEVELOPING FROM SOUTHWEST TO NORTHEAST ACROSS THE HEART OF THE FORECAST AREA...LIKELY REACHING THE CHICAGO AREA DURING THE 3-6 PM TIME. SO HAVE BUMPED UP POPS CONSIDERABLY. IN ADDITION...THE MID-LEVEL TEMPERATURES WILL CONTINUE TO COOL WITH THE FEATURE AND THE LOWER LEVELS THROUGH DIABATIC EFFECTS. ITS QUITE RARE TO SEE SNOW HERE DURING APRIL /ESPECIALLY MID-APRIL/ AFTERNOONS...BUT DO SEE PRECIPITATION STRUGGLING TO STAY AS RAIN GIVEN RAP AND NAM FORECAST THERMAL PROFILES AND JUST THE DEGREE OF FORCING. SO A QUICK TRANSITION TO A WET SNOW FROM NORTH TO SOUTH ACROSS THE CHICAGO METRO AREA IS FAVORED DURING THE RUSH HOUR...AND PROBABLY THE FIRST HALF AT THAT. SUPPRESSION ALOFT FOLLOWS BEHIND THE UPPER WAVE LATE THIS EVE INTO OVERNIGHT AND WILL END THE SNOW /FOR GOOD FINALLY?/. ANY INITIAL SNOW WILL STRUGGLE TO STICK WITH 4-INCH SOIL TEMPS AROUND 50 DEGREES AND THE WET GROUND IN PLACES...BUT THE FORCING LIKELY IS TO WIN OUT FOR A LIGHT COATING ESPECIALLY ON GRASSY SURFACES. THIS IS PRESENTLY MOST FAVORED ALONG AND SOUTH OF A MENDOTA TO CHICAGO LINE...AS THAT IS THE AREA THAT LOOKS TO HAVE THE BEST FORCING AS THE TEMPERATURES COOL LATE IN THE DAY AND THIS EVE. THERE IS UNCERTAINTY WITH THIS PLACEMENT THOUGH...AS SOME MESOSCALE PARAMETERS ARE AT PLAY. ACCUMULATION AROUND AN INCH TO A LITTLE OVER MAY OCCUR IN THE AREA THAT DOES END UP SEEING THE BETTER FORCING THANKS TO DECENT SNOWFALL RATES AT TIMES. TEMPERATURES WILL HOLD FLAT-LINE AND EVEN DROP DURING THE AFTERNOON AS PRECIPITATION EVOLVES INTO THE REGION. COLD AIR ADVECTION CONTINUES TONIGHT WITH 850MB TEMPS DROPPING TO THE -10C ARENA. THIS WILL SUPPORT CHICAGO CLOSING IN ON A RECORD LOW FOR TONIGHT /CALENDAR DAY OF APRIL 15/. SEE CLIMATE SECTION BELOW FOR MORE. TUESDAY THROUGH THURSDAY... NOT TOO MANY CHANGES MADE TO THIS PERIOD WHICH LOOKS MAINLY QUIET. A CHILLY TUESDAY IS EXPECTED WITH THE LOW STARTING POINT AND THE 850-925MB THERMAL TROUGH OVER US IN THE MORNING. A LAKE BREEZE DEVELOPING THAT AFTERNOON WILL NOT HELP MATTERS EITHER. UPPER 30S TO MID 40S ARE EXPECTED FROM NEAR THE LAKE TO THE REST OF THE FORECAST AREA ON TUESDAY AFTERNOON. UNCERTAINTY EXISTS ON CLOUD COVER FOR MUCH OF THIS TIME RANGE AND THAT WILL OF COURSE IMPACT TEMPERATURES GREATLY. THIS INCLUDES HIGH CLOUDS TUESDAY NIGHT WHICH COULD PREVENT ANOTHER CHILLY NIGHT IN THE 20S...AND HAVE INCHED UP FORECAST VALUES SOME FAVORING A LITTLE MORE CLOUD COVER AT THIS TIME. IN ADDITION...THURSDAY INTO THURSDAY NIGHT LOOKS TO HAVE SOUTHERLY FLOW AND THERE ARE INDICATIONS OF LOW CLOUDS MOVING NORTH DURING THAT TIME FRAME. WILL NEED TO WAIT TO THAT PERIOD GETS CLOSER TO GET TOO FANCY WITH TEMPERATURES BUT HAVE GONE WITH A BLEND OF GUIDANCE INCLUDING THE PREVIOUS FORECAST AT THIS TIME FOR TEMPS DURING THURSDAY. FRIDAY AND BEYOND... GIVEN A MASSIVE UPPER RIDGE OVER THE WESTERN TO NORTHERN ATLANTIC...ANY SHARP ADVANCEMENT OF AN UPPER RIDGE FROM THE WEST INTO OUR AREA LOOKS TO BE HALTED/SLOWED. WE WILL BUILD HEIGHTS GRADUALLY THURSDAY BUT MODEL GUIDANCE IS IN DECENT AGREEMENT WITH ADVANCING A PACIFIC SYSTEM INTO THE REGION BY FRIDAY AND PRODUCING LIKELY RAIN IN THE GENERAL REGION. THIS COULD SLOW GIVEN THE BACKED UP FLOW TO OUR EAST...AND HAVE TAKEN THAT INTO ACCOUNT FROM A SMART BLEND OF GUIDANCE POPS...SLOWING THEM SOMEWHAT. ONCE AGAIN TEMPERATURES ON FRIDAY DEPEND HEAVILY ON WHETHER OR NOT CLOUDS AND PRECIP ARE AS PROLIFIC AS MOST GUIDANCE IS INDICATING NOW. GRADUALLY BUILDING HEIGHTS SHOULD FOLLOW THAT SYSTEM DEPARTURE SOMETIME LATE FRIDAY/THIS WEEKEND. MTF && .CLIMATE... 625 AM CDT THE FOLLOWING ARE THE LAST APRIL DATES AND AMOUNTS OF ACCUMULATING SNOWFALL: CHICAGO: APRIL 18 2011 (0.6 IN.) ROCKFORD: APRIL 5 2009 (0.2 IN.) THE FOLLOWING ARE RECORD LOWS FOR THE MORNING OF APRIL 15TH. THE CHICAGO ONE IS THE MOST LIKELY IN JEOPARDY. CHICAGO: 25 (1943) ROCKFORD: 16 (1928) MTF && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 20Z... * MVFR CEILINGS...LOWERING BACK TOWARDS LOW END MVFR LATER THIS AFTERNOON. * GUSTY NORTH/NORTHWEST WINDS. * RAIN/SNOW MIX...WITH BETTER SNOW DEVELOPMENT MOVING OVER THE TERMINAL LATE THIS AFTERNOON INTO THE EARLY EVENING. * POSSIBLE LAKE EFFECT SNOW SHOWERS LINGERING INTO THE LATE EVENING. RODRIGUEZ //DISCUSSION...UPDATED 18Z... COMPLEX FORECAST THIS PERIOD AS A WINTRY MIX IS LIKELY THIS AFTERNOON INTO THE EVENING. LATEST RADAR IMAGERY DEPICTING CONTINUED LIGHT DEVELOPMENT AT THIS HOUR WITH ALL SNOW BEING REPORTED ACROSS NORTH/NORTHWEST ILLINOIS...AND THEN A RAIN SNOW MIX BEING REPORTED OVER AREAS IN NORTHEAST ILLINOIS. THIS LIGHTER DEVELOPMENT WILL LIKELY CONTINUE THROUGH MID AFTERNOON BEFORE A HEAVIER/STEADIER BAND OF LIGHT TO MODERATE SNOW MOVES THROUGH LATE THIS AFTERNOON INTO THE EARL EVENING...WITH ANY AREAS OBSERVING A RAIN/SNOW MIX OBSERVING A QUICK TRANSITION TO ALL SNOW. VIS AND CEILINGS WILL LIKELY LOWER UNDER THIS BETTER DEVELOPMENT...WITH IFR VIS AND LOW END MVFR CEILINGS LIKELY. THIS STEADIER SNOW SHOULD BEGIN TO SHIFT EAST OF THE TERMINALS LATER THIS EVENING...BUT WITH LAKE EFFECT DEVELOPMENT POSSIBLY LINGERING THROUGH THE MIDNIGHT TIME FRAME. CONFIDENCE IS LOW WITH REGARDS TO LAKE EFFECT SNOW DEVELOPMENT THIS EVENING/TONIGHT...AND WILL NEED TO MONITOR THIS POSSIBLE DEVELOPMENT. AREAS WILL THEN OBSERVE A CLEARING TREND OVERNIGHT...WITH VFR CONDITIONS THEN LIKELY TUESDAY. NORTHERLY WINDS MAY CONTINUE TO VARY BETWEEN NNW AND NNE OVER THE NEXT SEVERAL HOURS...BUT WITH A TREND TOWARDS NNW. HAVE CONTINUED TO LOWER SPEEDS/GUSTS THIS AFTERNOON WITH THE HIGHEST GUSTS OF AROUND 21KT NOW LIKELY EARLY THIS AFTERNOON. NORTHWEST WINDS WILL PREVAIL TONIGHT INTO TUESDAY...WITH SPEEDS DIMINISHING. RODRIGUEZ //ORD AND MDW CONFIDENCE...UPDATED 20Z... * MEDIUM HIGH CONFIDENCE WITH CEILING TRENDS. * MEDIUM HIGH CONFIDENCE IN WIND DIRECTION/SPEED. * MEDIUM HIGH CONFIDENCE WITH RAIN/SNOW AND ALL SNOW TRENDS AND TIMING. * LOW CONFIDENCE WITH LAKE EFFECT SNOW SHOWERS. RODRIGUEZ //OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z... TUESDAY NIGHT...VFR. WEDNESDAY...VFR. THURSDAY...VFR. FRIDAY...CHC RAIN. MVFR/IFR PSBL. SATURDAY...SLT CHC RAIN. MVFR/IFR PSBL. SUNDAY...CHC RAIN. MVFR/IFR PSBL. BMD && .MARINE... 240 AM CDT LOW PRESSURE IS MOVING ACROSS FAR SOUTHERN LAKE MICHIGAN EARLY THIS MORNING WITH GALE FORCE NORTHERLY WINDS OVERSPREADING THE LAKE BEHIND THE LOW AS IT BEGINS TO DEPART EAST. GALES ARE EXPECTED TO PERSIST THROUGH THE AFTERNOON...THEN SHOULD VERY GRADUALLY DIMINISH TO AROUND 30 KT THIS EVENING AND TONIGHT. FOG THAT WAS IN PLACE NEAR THE FRONTAL BOUNDARY ACROSS FAR SOUTHERN LAKE MICHIGAN SHOULD DIMINISH AS THE NORTHERLY WINDS OVERSPREAD THE LAKE. RIDGING WILL TRANSLATE ACROSS LAKE MICHIGAN LATE IN THE DAY TUESDAY ALLOWING WINDS TO BRIEFLY SUBSIDE...BUT SOUTH/SOUTHEAST WINDS PICK UP AGAIN ON WEDNESDAY AS ANOTHER LOW DEVELOPS OVER THE CENTRAL PLAINS. BMD && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565- LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868- LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 3 PM MONDAY. GALE WARNING...NEARSHORE WATERS UNTIL 4 PM MONDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
103 PM CDT MON APR 14 2014 .DISCUSSION... 1205 PM CDT CHALLENGING FORECAST CONTINUES THROUGH THE EVENING WITH PRECIP COVERAGE...INTENSITY...AND TYPE BEING THE MAIN FOCUS. LARGE SCALE UPPER TROUGH COVERING THE MID SECTION OF THE COUNTRY CONTINUES TO PIVOT EASTWARD PUSHING COLDER AIR INTO THE REGION. SUBTLE WAVES TRAVERSING THE FLOW CONTINUE TO WORK WITH COLD ADVECTION TO BRING PRECIP DEVELOPMENT. SURFACE TEMPS HAVE WARMED CENTRAL AND SOUTHEAST WHICH IS SUPPORTIVE OF MORE RAIN BUT TEMPERATURES WILL LIKELY COOL INTO THE AFTERNOON FROM THE NORTHWEST. THEREFORE...PRECIP TYPE THROUGH EARLY AFTERNOON WILL LIKELY BE RAIN OR SNOW EXCEPT FOR FAR SOUTHEAST AREAS THAT WOULD SEE RAIN...THOUGH PRECIP CHANCES ARE LOWER THERE. WATER VAPOR SHOWS A MORE ORGANIZED SHORTWAVE STARTING TO EJECT NORTHEAST FROM SOUTHWEST MISSOURI AND EASTERN OKLAHOMA AND KANSAS. THIS WAVE WILL LIFT INTO THE AREA LATE THIS AFTERNOON INTO THE EARLY EVENING AND TIGHTEN THE MID LEVEL BAROCLINIC ZONE RESULTING IN INTENSIFYING FRONTOGENESIS. RADAR MOSAIC SHOWS BANDS OF PRECIP DEVELOPING NORTHEASTWARD IN CONJUNCTION WITH THIS FEATURE. WILL CONTINUE WITH THE IDEA OF A MORE FOCUSED PERIOD OF PRECIPITATION LATE THIS AFTERNOON INTO THE EVENING BUT HAVE TRIED TO REFINE DETAILS. WHILE PRECIP WILL CONTINUE ON AND OFF THROUGH THE AFTERNOON...HAVE SLOWED THE PERIOD OF BETTER COVERAGE/INTENSITY SLIGHTLY. FORECAST SOUNDINGS/CONCEPTUAL MODELS SUPPORT ALL SNOW WITHIN THE MOST INTENSE BAND THANKS TO WELL ALIGNED ASCENT WITHIN THE SNOW GROWTH ZONE AND COOLING LOW LEVEL TEMP PROFILES. EXPECT THAT THERE WILL BE A CORRIDOR OF MODERATE SNOW WITHIN A LARGER AREA OF LESS INTENSE PRECIP THAT WILL DEVELOP NORTHWARD ALONG A LINE FROM ROUGHLY CHICAGO TO MENDOTA...THEN PIVOT EASTWARD INTO THE EVENING. MUCH OF THE EVENING RUSH HOUR IN THE CHICAGO METRO LOOKS TO FALL INTO THE PERIOD OF MORE INTENSE SNOWFALL...WHICH MAY LAST A FEW HOURS. THE VORT MAX LIFTS NORTHEAST WHICH MAY BRING A LULL IN THE PRECIP EARLY THIS EVENING BUT LARGER SCALE FORCING INCREASES TO THE EAST SO THERE MAY BE RE-INTENSIFICATION OVER NORTHWEST INDIANA BY MID EVENING BEFORE PRECIP EXITS LATE EVENING. TEMPERATURES WILL LIKELY COOL INTO THE MID 30S LATER TODAY AND SNOW SHOULD FALL AT AN INTENSE ENOUGH RATE TO PROVIDE FOR ACCUMULATION ON GRASSY SURFACES AND SLUSHY ACCUMULATION ON ROADS. WILL CONTINUE WITH THE IDEA OF AROUND AN INCH OF ACCUMULATION. MDB //PREV DISCUSSION... 330 AM CDT THE INFAMOUS WINTER 2013-2014 BEGAN IN OCTOBER WITH SNOW AND TODAY IT WANTS TO MAKE SURE IT INCLUDES APRIL TO ENCOMPASS SEVEN MONTHS. THIS UNFRIENDLY VERY LATE VISIT FROM WINTER WAS THE PRIMARY FORECAST CHALLENGE...ALONG WITH TEMPERATURES THROUGHOUT THE WEEK AS WE WILL BE WELL BELOW NORMAL TO START THIS WEEK...POTENTIALLY TO RECORD LEVELS TONIGHT. THIS MORNING... THE 995MB SURFACE LOW IS PASSING OVER THE NORTH METRO OF CHICAGO EARLY THIS MORNING AND 30 MILES EITHER SIDE OF ITS PATH SEPARATES 60S AND CONVECTIVE RAIN SHOWERS AND 30S AND DEFORMATION SNOW. THE DEEPENING AND CLASSIC LOOKING UPPER WAVE WITH THIS IS ADVANCING NORTHEAST FROM SOUTHWEST WI AND ITS DEFORMATION AND WRAPAROUND MOISTURE WILL ONLY GRAZE THE AREA THIS MORNING. WHILE A MIX WITH WET SNOW IS PROBABLE OVER PARTS OF NORTH CENTRAL IL...THE FORCING FOR MODEST SNOW RATES IS LIKELY TO REMAIN TO THE NORTH IN THE A.M. HOURS SO NOT EXPECTING ANY ACCUMULATIONS PRIOR TO NOON. WINDS ON THE BACKSIDE OF THE LOW THIS MORNING LOOK TO GUST TO AROUND 40 MPH AT TIMES...WHICH BESIDES ADDING QUITE A CHILL TO THE AIR...MAY REDUCE VISIBILITY UP BY ROCKFORD IF SNOW CAN MATERIALIZE THIS MORNING. OTHERWISE THOUGH...IMPACTS LOOK MINOR DURING THIS PERIOD. THIS AFTERNOON AND TONIGHT... A SECOND WELL-DEFINED UPPER CIRCULATION IS ADVANCING EASTWARD INTO THE CENTRAL PLAINS EARLY THIS MORNING. THIS IS BASICALLY ROUNDING THE BASE OF WHAT REALLY IS A MASSIVE LONGWAVE TROUGH ACROSS CENTRAL NORTH AMERICA...WITH AN IMPRESSIVE JANUARY-LIKE -40C OBSERVED AT 500MB LAST NIGHT ALL THE WAY SOUTH TO CYQD IN SOUTHERN MANITOBA. GIVEN THE UPPER FLOW...PV ANOMALY EVOLUTION...AND MID-LEVEL BAROCLINICITY...THIS WAVE IS FORECAST TO TURN MORE NORTHEAST THIS AFTERNOON AND ADVANCE INTO CENTRAL AND NORTHERN IL/IN DURING THE MID-AFTERNOON INTO MID-EVE. THIS WILL BRING WITH IT FOCUSED OMEGA AND FRONTOGENETIC SUPPORTED UPWARD MOTION DURING THAT PERIOD AND WOULD EXPECT TO SEE MODERATE PRECIPITATION DEVELOPING FROM SOUTHWEST TO NORTHEAST ACROSS THE HEART OF THE FORECAST AREA...LIKELY REACHING THE CHICAGO AREA DURING THE 3-6 PM TIME. SO HAVE BUMPED UP POPS CONSIDERABLY. IN ADDITION...THE MID-LEVEL TEMPERATURES WILL CONTINUE TO COOL WITH THE FEATURE AND THE LOWER LEVELS THROUGH DIABATIC EFFECTS. ITS QUITE RARE TO SEE SNOW HERE DURING APRIL /ESPECIALLY MID-APRIL/ AFTERNOONS...BUT DO SEE PRECIPITATION STRUGGLING TO STAY AS RAIN GIVEN RAP AND NAM FORECAST THERMAL PROFILES AND JUST THE DEGREE OF FORCING. SO A QUICK TRANSITION TO A WET SNOW FROM NORTH TO SOUTH ACROSS THE CHICAGO METRO AREA IS FAVORED DURING THE RUSH HOUR...AND PROBABLY THE FIRST HALF AT THAT. SUPPRESSION ALOFT FOLLOWS BEHIND THE UPPER WAVE LATE THIS EVE INTO OVERNIGHT AND WILL END THE SNOW /FOR GOOD FINALLY?/. ANY INITIAL SNOW WILL STRUGGLE TO STICK WITH 4-INCH SOIL TEMPS AROUND 50 DEGREES AND THE WET GROUND IN PLACES...BUT THE FORCING LIKELY IS TO WIN OUT FOR A LIGHT COATING ESPECIALLY ON GRASSY SURFACES. THIS IS PRESENTLY MOST FAVORED ALONG AND SOUTH OF A MENDOTA TO CHICAGO LINE...AS THAT IS THE AREA THAT LOOKS TO HAVE THE BEST FORCING AS THE TEMPERATURES COOL LATE IN THE DAY AND THIS EVE. THERE IS UNCERTAINTY WITH THIS PLACEMENT THOUGH...AS SOME MESOSCALE PARAMETERS ARE AT PLAY. ACCUMULATION AROUND AN INCH TO A LITTLE OVER MAY OCCUR IN THE AREA THAT DOES END UP SEEING THE BETTER FORCING THANKS TO DECENT SNOWFALL RATES AT TIMES. TEMPERATURES WILL HOLD FLAT-LINE AND EVEN DROP DURING THE AFTERNOON AS PRECIPITATION EVOLVES INTO THE REGION. COLD AIR ADVECTION CONTINUES TONIGHT WITH 850MB TEMPS DROPPING TO THE -10C ARENA. THIS WILL SUPPORT CHICAGO CLOSING IN ON A RECORD LOW FOR TONIGHT /CALENDAR DAY OF APRIL 15/. SEE CLIMATE SECTION BELOW FOR MORE. TUESDAY THROUGH THURSDAY... NOT TOO MANY CHANGES MADE TO THIS PERIOD WHICH LOOKS MAINLY QUIET. A CHILLY TUESDAY IS EXPECTED WITH THE LOW STARTING POINT AND THE 850-925MB THERMAL TROUGH OVER US IN THE MORNING. A LAKE BREEZE DEVELOPING THAT AFTERNOON WILL NOT HELP MATTERS EITHER. UPPER 30S TO MID 40S ARE EXPECTED FROM NEAR THE LAKE TO THE REST OF THE FORECAST AREA ON TUESDAY AFTERNOON. UNCERTAINTY EXISTS ON CLOUD COVER FOR MUCH OF THIS TIME RANGE AND THAT WILL OF COURSE IMPACT TEMPERATURES GREATLY. THIS INCLUDES HIGH CLOUDS TUESDAY NIGHT WHICH COULD PREVENT ANOTHER CHILLY NIGHT IN THE 20S...AND HAVE INCHED UP FORECAST VALUES SOME FAVORING A LITTLE MORE CLOUD COVER AT THIS TIME. IN ADDITION...THURSDAY INTO THURSDAY NIGHT LOOKS TO HAVE SOUTHERLY FLOW AND THERE ARE INDICATIONS OF LOW CLOUDS MOVING NORTH DURING THAT TIME FRAME. WILL NEED TO WAIT TO THAT PERIOD GETS CLOSER TO GET TOO FANCY WITH TEMPERATURES BUT HAVE GONE WITH A BLEND OF GUIDANCE INCLUDING THE PREVIOUS FORECAST AT THIS TIME FOR TEMPS DURING THURSDAY. FRIDAY AND BEYOND... GIVEN A MASSIVE UPPER RIDGE OVER THE WESTERN TO NORTHERN ATLANTIC...ANY SHARP ADVANCEMENT OF AN UPPER RIDGE FROM THE WEST INTO OUR AREA LOOKS TO BE HALTED/SLOWED. WE WILL BUILD HEIGHTS GRADUALLY THURSDAY BUT MODEL GUIDANCE IS IN DECENT AGREEMENT WITH ADVANCING A PACIFIC SYSTEM INTO THE REGION BY FRIDAY AND PRODUCING LIKELY RAIN IN THE GENERAL REGION. THIS COULD SLOW GIVEN THE BACKED UP FLOW TO OUR EAST...AND HAVE TAKEN THAT INTO ACCOUNT FROM A SMART BLEND OF GUIDANCE POPS...SLOWING THEM SOMEWHAT. ONCE AGAIN TEMPERATURES ON FRIDAY DEPEND HEAVILY ON WHETHER OR NOT CLOUDS AND PRECIP ARE AS PROLIFIC AS MOST GUIDANCE IS INDICATING NOW. GRADUALLY BUILDING HEIGHTS SHOULD FOLLOW THAT SYSTEM DEPARTURE SOMETIME LATE FRIDAY/THIS WEEKEND. MTF && .CLIMATE... 625 AM CDT THE FOLLOWING ARE THE LAST APRIL DATES AND AMOUNTS OF ACCUMULATING SNOWFALL: CHICAGO: APRIL 18 2011 (0.6 IN.) ROCKFORD: APRIL 5 2009 (0.2 IN.) THE FOLLOWING ARE RECORD LOWS FOR THE MORNING OF APRIL 15TH. THE CHICAGO ONE IS THE MOST LIKELY IN JEOPARDY. CHICAGO: 25 (1943) ROCKFORD: 16 (1928) MTF && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 18Z... * MVFR CEILINGS...LOWERING BACK TOWARDS LOW END MVFR LATER THIS AFTERNOON. * GUSTY NORTHERLY WINDS. * RAIN/SNOW MIX EARLY THIS AFTERNOON...WITH BETTER SNOW DEVELOPMENT MOVING OVER THE TERMINAL LATE THIS AFTERNOON INTO THE EARLY EVENING. * POSSIBLE LAKE EFFECT SNOW SHOWERS LINGERING INTO THE LATE EVENING. RODRIGUEZ //DISCUSSION...UPDATED 18Z... COMPLEX FORECAST THIS PERIOD AS A WINTRY MIX IS LIKELY THIS AFTERNOON INTO THE EVENING. LATEST RADAR IMAGERY DEPICTING CONTINUED LIGHT DEVELOPMENT AT THIS HOUR WITH ALL SNOW BEING REPORTED ACROSS NORTH/NORTHWEST ILLINOIS...AND THEN A RAIN SNOW MIX BEING REPORTED OVER AREAS IN NORTHEAST ILLINOIS. THIS LIGHTER DEVELOPMENT WILL LIKELY CONTINUE THROUGH MID AFTERNOON BEFORE A HEAVIER/STEADIER BAND OF LIGHT TO MODERATE SNOW MOVES THROUGH LATE THIS AFTERNOON INTO THE EARL EVENING...WITH ANY AREAS OBSERVING A RAIN/SNOW MIX OBSERVING A QUICK TRANSITION TO ALL SNOW. VIS AND CEILINGS WILL LIKELY LOWER UNDER THIS BETTER DEVELOPMENT...WITH IFR VIS AND LOW END MVFR CEILINGS LIKELY. THIS STEADIER SNOW SHOULD BEGIN TO SHIFT EAST OF THE TERMINALS LATER THIS EVENING...BUT WITH LAKE EFFECT DEVELOPMENT POSSIBLY LINGERING THROUGH THE MIDNIGHT TIME FRAME. CONFIDENCE IS LOW WITH REGARDS TO LAKE EFFECT SNOW DEVELOPMENT THIS EVENING/TONIGHT...AND WILL NEED TO MONITOR THIS POSSIBLE DEVELOPMENT. AREAS WILL THEN OBSERVE A CLEARING TREND OVERNIGHT...WITH VFR CONDITIONS THEN LIKELY TUESDAY. NORTHERLY WINDS MAY CONTINUE TO VARY BETWEEN NNW AND NNE OVER THE NEXT SEVERAL HOURS...BUT WITH A TREND TOWARDS NNW. HAVE CONTINUED TO LOWER SPEEDS/GUSTS THIS AFTERNOON WITH THE HIGHEST GUSTS OF AROUND 21KT NOW LIKELY EARLY THIS AFTERNOON. NORTHWEST WINDS WILL PREVAIL TONIGHT INTO TUESDAY...WITH SPEEDS DIMINISHING. RODRIGUEZ //ORD AND MDW CONFIDENCE...UPDATED 18Z... * MEDIUM HIGH CONFIDENCE WITH CEILING TRENDS. * MEDIUM HIGH CONFIDENCE IN WIND DIRECTION/SPEED. * MEDIUM HIGH CONFIDENCE WITH RAIN/SNOW AND ALL SNOW TRENDS AND TIMING. * LOW CONFIDENCE WITH LAKE EFFECT SNOW SHOWERS. RODRIGUEZ //OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z... TUESDAY NIGHT...VFR. WEDNESDAY...VFR. THURSDAY...VFR. FRIDAY...CHC RAIN. MVFR/IFR PSBL. SATURDAY...SLT CHC RAIN. MVFR/IFR PSBL. SUNDAY...CHC RAIN. MVFR/IFR PSBL. BMD && .MARINE... 240 AM CDT LOW PRESSURE IS MOVING ACROSS FAR SOUTHERN LAKE MICHIGAN EARLY THIS MORNING WITH GALE FORCE NORTHERLY WINDS OVERSPREADING THE LAKE BEHIND THE LOW AS IT BEGINS TO DEPART EAST. GALES ARE EXPECTED TO PERSIST THROUGH THE AFTERNOON...THEN SHOULD VERY GRADUALLY DIMINISH TO AROUND 30 KT THIS EVENING AND TONIGHT. FOG THAT WAS IN PLACE NEAR THE FRONTAL BOUNDARY ACROSS FAR SOUTHERN LAKE MICHIGAN SHOULD DIMINISH AS THE NORTHERLY WINDS OVERSPREAD THE LAKE. RIDGING WILL TRANSLATE ACROSS LAKE MICHIGAN LATE IN THE DAY TUESDAY ALLOWING WINDS TO BRIEFLY SUBSIDE...BUT SOUTH/SOUTHEAST WINDS PICK UP AGAIN ON WEDNESDAY AS ANOTHER LOW DEVELOPS OVER THE CENTRAL PLAINS. BMD && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565- LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868- LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 3 PM MONDAY. GALE WARNING...NEARSHORE WATERS UNTIL 4 PM MONDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1210 PM CDT MON APR 14 2014 .DISCUSSION... 1205 PM CDT CHALLENGING FORECAST CONTINUES THROUGH THE EVENING WITH PRECIP COVERAGE...INTENSITY...AND TYPE BEING THE MAIN FOCUS. LARGE SCALE UPPER TROUGH COVERING THE MID SECTION OF THE COUNTRY CONTINUES TO PIVOT EASTWARD PUSHING COLDER AIR INTO THE REGION. SUBTLE WAVES TRAVERSING THE FLOW CONTINUE TO WORK WITH COLD ADVECTION TO BRING PRECIP DEVELOPMENT. SURFACE TEMPS HAVE WARMED CENTRAL AND SOUTHEAST WHICH IS SUPPORTIVE OF MORE RAIN BUT TEMPERATURES WILL LIKELY COOL INTO THE AFTERNOON FROM THE NORTHWEST. THEREFORE...PRECIP TYPE THROUGH EARLY AFTERNOON WILL LIKELY BE RAIN OR SNOW EXCEPT FOR FAR SOUTHEAST AREAS THAT WOULD SEE RAIN...THOUGH PRECIP CHANCES ARE LOWER THERE. WATER VAPOR SHOWS A MORE ORGANIZED SHORTWAVE STARTING TO EJECT NORTHEAST FROM SOUTHWEST MISSOURI AND EASTERN OKLAHOMA AND KANSAS. THIS WAVE WILL LIFT INTO THE AREA LATE THIS AFTERNOON INTO THE EARLY EVENING AND TIGHTEN THE MID LEVEL BAROCLINIC ZONE RESULTING IN INTENSIFYING FRONTOGENESIS. RADAR MOSAIC SHOWS BANDS OF PRECIP DEVELOPING NORTHEASTWARD IN CONJUNCTION WITH THIS FEATURE. WILL CONTINUE WITH THE IDEA OF A MORE FOCUSED PERIOD OF PRECIPITATION LATE THIS AFTERNOON INTO THE EVENING BUT HAVE TRIED TO REFINE DETAILS. WHILE PRECIP WILL CONTINUE ON AND OFF THROUGH THE AFTERNOON...HAVE SLOWED THE PERIOD OF BETTER COVERAGE/INTENSITY SLIGHTLY. FORECAST SOUNDINGS/CONCEPTUAL MODELS SUPPORT ALL SNOW WITHIN THE MOST INTENSE BAND THANKS TO WELL ALIGNED ASCENT WITHIN THE SNOW GROWTH ZONE AND COOLING LOW LEVEL TEMP PROFILES. EXPECT THAT THERE WILL BE A CORRIDOR OF MODERATE SNOW WITHIN A LARGER AREA OF LESS INTENSE PRECIP THAT WILL DEVELOP NORTHWARD ALONG A LINE FROM ROUGHLY CHICAGO TO MENDOTA...THEN PIVOT EASTWARD INTO THE EVENING. MUCH OF THE EVENING RUSH HOUR IN THE CHICAGO METRO LOOKS TO FALL INTO THE PERIOD OF MORE INTENSE SNOWFALL...WHICH MAY LAST A FEW HOURS. THE VORT MAX LIFTS NORTHEAST WHICH MAY BRING A LULL IN THE PRECIP EARLY THIS EVENING BUT LARGER SCALE FORCING INCREASES TO THE EAST SO THERE MAY BE RE-INTENSIFICATION OVER NORTHWEST INDIANA BY MID EVENING BEFORE PRECIP EXITS LATE EVENING. TEMPERATURES WILL LIKELY COOL INTO THE MID 30S LATER TODAY AND SNOW SHOULD FALL AT AN INTENSE ENOUGH RATE TO PROVIDE FOR ACCUMULATION ON GRASSY SURFACES AND SLUSHY ACCUMULATION ON ROADS. WILL CONTINUE WITH THE IDEA OF AROUND AN INCH OF ACCUMULATION. MDB && .PREV DISCUSSION... 330 AM CDT THE INFAMOUS WINTER 2013-2014 BEGAN IN OCTOBER WITH SNOW AND TODAY IT WANTS TO MAKE SURE IT INCLUDES APRIL TO ENCOMPASS SEVEN MONTHS. THIS UNFRIENDLY VERY LATE VISIT FROM WINTER WAS THE PRIMARY FORECAST CHALLENGE...ALONG WITH TEMPERATURES THROUGHOUT THE WEEK AS WE WILL BE WELL BELOW NORMAL TO START THIS WEEK...POTENTIALLY TO RECORD LEVELS TONIGHT. THIS MORNING... THE 995MB SURFACE LOW IS PASSING OVER THE NORTH METRO OF CHICAGO EARLY THIS MORNING AND 30 MILES EITHER SIDE OF ITS PATH SEPARATES 60S AND CONVECTIVE RAIN SHOWERS AND 30S AND DEFORMATION SNOW. THE DEEPENING AND CLASSIC LOOKING UPPER WAVE WITH THIS IS ADVANCING NORTHEAST FROM SOUTHWEST WI AND ITS DEFORMATION AND WRAPAROUND MOISTURE WILL ONLY GRAZE THE AREA THIS MORNING. WHILE A MIX WITH WET SNOW IS PROBABLE OVER PARTS OF NORTH CENTRAL IL...THE FORCING FOR MODEST SNOW RATES IS LIKELY TO REMAIN TO THE NORTH IN THE A.M. HOURS SO NOT EXPECTING ANY ACCUMULATIONS PRIOR TO NOON. WINDS ON THE BACKSIDE OF THE LOW THIS MORNING LOOK TO GUST TO AROUND 40 MPH AT TIMES...WHICH BESIDES ADDING QUITE A CHILL TO THE AIR...MAY REDUCE VISIBILITY UP BY ROCKFORD IF SNOW CAN MATERIALIZE THIS MORNING. OTHERWISE THOUGH...IMPACTS LOOK MINOR DURING THIS PERIOD. THIS AFTERNOON AND TONIGHT... A SECOND WELL-DEFINED UPPER CIRCULATION IS ADVANCING EASTWARD INTO THE CENTRAL PLAINS EARLY THIS MORNING. THIS IS BASICALLY ROUNDING THE BASE OF WHAT REALLY IS A MASSIVE LONGWAVE TROUGH ACROSS CENTRAL NORTH AMERICA...WITH AN IMPRESSIVE JANUARY-LIKE -40C OBSERVED AT 500MB LAST NIGHT ALL THE WAY SOUTH TO CYQD IN SOUTHERN MANITOBA. GIVEN THE UPPER FLOW...PV ANOMALY EVOLUTION...AND MID-LEVEL BAROCLINICITY...THIS WAVE IS FORECAST TO TURN MORE NORTHEAST THIS AFTERNOON AND ADVANCE INTO CENTRAL AND NORTHERN IL/IN DURING THE MID-AFTERNOON INTO MID-EVE. THIS WILL BRING WITH IT FOCUSED OMEGA AND FRONTOGENETIC SUPPORTED UPWARD MOTION DURING THAT PERIOD AND WOULD EXPECT TO SEE MODERATE PRECIPITATION DEVELOPING FROM SOUTHWEST TO NORTHEAST ACROSS THE HEART OF THE FORECAST AREA...LIKELY REACHING THE CHICAGO AREA DURING THE 3-6 PM TIME. SO HAVE BUMPED UP POPS CONSIDERABLY. IN ADDITION...THE MID-LEVEL TEMPERATURES WILL CONTINUE TO COOL WITH THE FEATURE AND THE LOWER LEVELS THROUGH DIABATIC EFFECTS. ITS QUITE RARE TO SEE SNOW HERE DURING APRIL /ESPECIALLY MID-APRIL/ AFTERNOONS...BUT DO SEE PRECIPITATION STRUGGLING TO STAY AS RAIN GIVEN RAP AND NAM FORECAST THERMAL PROFILES AND JUST THE DEGREE OF FORCING. SO A QUICK TRANSITION TO A WET SNOW FROM NORTH TO SOUTH ACROSS THE CHICAGO METRO AREA IS FAVORED DURING THE RUSH HOUR...AND PROBABLY THE FIRST HALF AT THAT. SUPPRESSION ALOFT FOLLOWS BEHIND THE UPPER WAVE LATE THIS EVE INTO OVERNIGHT AND WILL END THE SNOW /FOR GOOD FINALLY?/. ANY INITIAL SNOW WILL STRUGGLE TO STICK WITH 4-INCH SOIL TEMPS AROUND 50 DEGREES AND THE WET GROUND IN PLACES...BUT THE FORCING LIKELY IS TO WIN OUT FOR A LIGHT COATING ESPECIALLY ON GRASSY SURFACES. THIS IS PRESENTLY MOST FAVORED ALONG AND SOUTH OF A MENDOTA TO CHICAGO LINE...AS THAT IS THE AREA THAT LOOKS TO HAVE THE BEST FORCING AS THE TEMPERATURES COOL LATE IN THE DAY AND THIS EVE. THERE IS UNCERTAINTY WITH THIS PLACEMENT THOUGH...AS SOME MESOSCALE PARAMETERS ARE AT PLAY. ACCUMULATION AROUND AN INCH TO A LITTLE OVER MAY OCCUR IN THE AREA THAT DOES END UP SEEING THE BETTER FORCING THANKS TO DECENT SNOWFALL RATES AT TIMES. TEMPERATURES WILL HOLD FLAT-LINE AND EVEN DROP DURING THE AFTERNOON AS PRECIPITATION EVOLVES INTO THE REGION. COLD AIR ADVECTION CONTINUES TONIGHT WITH 850MB TEMPS DROPPING TO THE -10C ARENA. THIS WILL SUPPORT CHICAGO CLOSING IN ON A RECORD LOW FOR TONIGHT /CALENDAR DAY OF APRIL 15/. SEE CLIMATE SECTION BELOW FOR MORE. TUESDAY THROUGH THURSDAY... NOT TOO MANY CHANGES MADE TO THIS PERIOD WHICH LOOKS MAINLY QUIET. A CHILLY TUESDAY IS EXPECTED WITH THE LOW STARTING POINT AND THE 850-925MB THERMAL TROUGH OVER US IN THE MORNING. A LAKE BREEZE DEVELOPING THAT AFTERNOON WILL NOT HELP MATTERS EITHER. UPPER 30S TO MID 40S ARE EXPECTED FROM NEAR THE LAKE TO THE REST OF THE FORECAST AREA ON TUESDAY AFTERNOON. UNCERTAINTY EXISTS ON CLOUD COVER FOR MUCH OF THIS TIME RANGE AND THAT WILL OF COURSE IMPACT TEMPERATURES GREATLY. THIS INCLUDES HIGH CLOUDS TUESDAY NIGHT WHICH COULD PREVENT ANOTHER CHILLY NIGHT IN THE 20S...AND HAVE INCHED UP FORECAST VALUES SOME FAVORING A LITTLE MORE CLOUD COVER AT THIS TIME. IN ADDITION...THURSDAY INTO THURSDAY NIGHT LOOKS TO HAVE SOUTHERLY FLOW AND THERE ARE INDICATIONS OF LOW CLOUDS MOVING NORTH DURING THAT TIME FRAME. WILL NEED TO WAIT TO THAT PERIOD GETS CLOSER TO GET TOO FANCY WITH TEMPERATURES BUT HAVE GONE WITH A BLEND OF GUIDANCE INCLUDING THE PREVIOUS FORECAST AT THIS TIME FOR TEMPS DURING THURSDAY. FRIDAY AND BEYOND... GIVEN A MASSIVE UPPER RIDGE OVER THE WESTERN TO NORTHERN ATLANTIC...ANY SHARP ADVANCEMENT OF AN UPPER RIDGE FROM THE WEST INTO OUR AREA LOOKS TO BE HALTED/SLOWED. WE WILL BUILD HEIGHTS GRADUALLY THURSDAY BUT MODEL GUIDANCE IS IN DECENT AGREEMENT WITH ADVANCING A PACIFIC SYSTEM INTO THE REGION BY FRIDAY AND PRODUCING LIKELY RAIN IN THE GENERAL REGION. THIS COULD SLOW GIVEN THE BACKED UP FLOW TO OUR EAST...AND HAVE TAKEN THAT INTO ACCOUNT FROM A SMART BLEND OF GUIDANCE POPS...SLOWING THEM SOMEWHAT. ONCE AGAIN TEMPERATURES ON FRIDAY DEPEND HEAVILY ON WHETHER OR NOT CLOUDS AND PRECIP ARE AS PROLIFIC AS MOST GUIDANCE IS INDICATING NOW. GRADUALLY BUILDING HEIGHTS SHOULD FOLLOW THAT SYSTEM DEPARTURE SOMETIME LATE FRIDAY/THIS WEEKEND. MTF && .CLIMATE... 625 AM CDT THE FOLLOWING ARE THE LAST APRIL DATES AND AMOUNTS OF ACCUMULATING SNOWFALL: CHICAGO: APRIL 18 2011 (0.6 IN.) ROCKFORD: APRIL 5 2009 (0.2 IN.) THE FOLLOWING ARE RECORD LOWS FOR THE MORNING OF APRIL 15TH. THE CHICAGO ONE IS THE MOST LIKELY IN JEOPARDY. CHICAGO: 25 (1943) ROCKFORD: 16 (1928) MTF && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 16Z... * MVFR CIGS...LOWERING BACK TOWARDS LOW END MVFR LATER THIS AFTERNOON. * GUSTY N WINDS THROUGH THE DAY...POSSIBLY TURNING NNE BY EARLY AFTERNOON. * SNOW OVERSPREADING THE TERMINALS MID AFTERNOON WITH MINOR ACCUMULATIONS. BMD //DISCUSSION...UPDATED 12Z... A COLD FRONT IS WORKING ACROSS NORTHEASTERN ILLINOIS EARLY THIS MORNING WITH WINDS TURNING SHARPLY TO THE NNW WITH GUSTS TO AROUND 30 KT. AREA OBSERVATIONS SHOW A NARROW CORRIDOR OF IFR CIGS IN THE VICINITY OF THE FRONT...WHICH HAS BEEN SHRINKING OVERNIGHT WITH PRIMARILY MVFR CIGS EXPECTED THIS MORNING. PRECIP HAS ALSO DWINDLED AND EXPECTED A COUPLE HOURS OF LIGHT RAIN/DRIZZLE EARLY THIS MORNING THEN DRY CONDITIONS SHOULD PREVAIL THROUGH AROUND MID AFTERNOON. AT THAT TIME...AN UPPER LEVEL DISTURBANCE WILL MOVE ACROSS THE AREA WITH PRECIP OVERSPREADING THE AREA FROM THE SOUTHWEST. RFD MAY BE CLIPPED BY THIS PRECIP...BUT THE CHICAGO TERMINALS ARE EXPECTED TO TAKE A MORE DIRECT SHOT. AT THE ONSET...TEMPERATURES MAY BE WARM ENOUGH FOR A MIX OF RAIN AND SNOW...PARTICULARLY AT MDW AND GYY...BUT THE COLUMN WILL COOL AND EXPECT A TRANSITION TO ALL SNOW WITH MINOR ACCUMULATIONS POSSIBLE...ESPECIALLY ON GRASSY SURFACES... OF UP TO AROUND AND INCH. WINDS SHOULD PRIMARILY REMAIN IN THE 330-360 DIRECTION TODAY WITH GUSTS AROUND 30 KT THIS MORNING VERY SLOWLY TAPERING THROUGH THE DAY. BMD //ORD AND MDW CONFIDENCE...UPDATED 16Z... * MEDIUM HIGH CONFIDENCE WITH CIGS. * MEDIUM-HIGH CONFIDENCE IN WIND DIRECTION/SPEED. * MEDIUM-HIGH CONFIDENCE IN SNOW TIMING THIS AFTERNOON. BMD //OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z... TUESDAY NIGHT...VFR. WEDNESDAY...VFR. THURSDAY...VFR. FRIDAY...CHC RAIN. MVFR/IFR PSBL. SATURDAY...SLT CHC RAIN. MVFR/IFR PSBL. SUNDAY...CHC RAIN. MVFR/IFR PSBL. BMD && .MARINE... 240 AM CDT LOW PRESSURE IS MOVING ACROSS FAR SOUTHERN LAKE MICHIGAN EARLY THIS MORNING WITH GALE FORCE NORTHERLY WINDS OVERSPREADING THE LAKE BEHIND THE LOW AS IT BEGINS TO DEPART EAST. GALES ARE EXPECTED TO PERSIST THROUGH THE AFTERNOON...THEN SHOULD VERY GRADUALLY DIMINISH TO AROUND 30 KT THIS EVENING AND TONIGHT. FOG THAT WAS IN PLACE NEAR THE FRONTAL BOUNDARY ACROSS FAR SOUTHERN LAKE MICHIGAN SHOULD DIMINISH AS THE NORTHERLY WINDS OVERSPREAD THE LAKE. RIDGING WILL TRANSLATE ACROSS LAKE MICHIGAN LATE IN THE DAY TUESDAY ALLOWING WINDS TO BRIEFLY SUBSIDE...BUT SOUTH/SOUTHEAST WINDS PICK UP AGAIN ON WEDNESDAY AS ANOTHER LOW DEVELOPS OVER THE CENTRAL PLAINS. BMD && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565- LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868- LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 3 PM MONDAY. GALE WARNING...NEARSHORE WATERS UNTIL 4 PM MONDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1148 AM CDT MON APR 14 2014 .DISCUSSION... 330 AM CDT THE INFAMOUS WINTER 2013-2014 BEGAN IN OCTOBER WITH SNOW AND TODAY IT WANTS TO MAKE SURE IT INCLUDES APRIL TO ENCOMPASS SEVEN MONTHS. THIS UNFRIENDLY VERY LATE VISIT FROM WINTER WAS THE PRIMARY FORECAST CHALLENGE...ALONG WITH TEMPERATURES THROUGHOUT THE WEEK AS WE WILL BE WELL BELOW NORMAL TO START THIS WEEK...POTENTIALLY TO RECORD LEVELS TONIGHT. THIS MORNING... THE 995MB SURFACE LOW IS PASSING OVER THE NORTH METRO OF CHICAGO EARLY THIS MORNING AND 30 MILES EITHER SIDE OF ITS PATH SEPARATES 60S AND CONVECTIVE RAIN SHOWERS AND 30S AND DEFORMATION SNOW. THE DEEPENING AND CLASSIC LOOKING UPPER WAVE WITH THIS IS ADVANCING NORTHEAST FROM SOUTHWEST WI AND ITS DEFORMATION AND WRAPAROUND MOISTURE WILL ONLY GRAZE THE AREA THIS MORNING. WHILE A MIX WITH WET SNOW IS PROBABLE OVER PARTS OF NORTH CENTRAL IL...THE FORCING FOR MODEST SNOW RATES IS LIKELY TO REMAIN TO THE NORTH IN THE A.M. HOURS SO NOT EXPECTING ANY ACCUMULATIONS PRIOR TO NOON. WINDS ON THE BACKSIDE OF THE LOW THIS MORNING LOOK TO GUST TO AROUND 40 MPH AT TIMES...WHICH BESIDES ADDING QUITE A CHILL TO THE AIR...MAY REDUCE VISIBILITY UP BY ROCKFORD IF SNOW CAN MATERIALIZE THIS MORNING. OTHERWISE THOUGH...IMPACTS LOOK MINOR DURING THIS PERIOD. THIS AFTERNOON AND TONIGHT... A SECOND WELL-DEFINED UPPER CIRCULATION IS ADVANCING EASTWARD INTO THE CENTRAL PLAINS EARLY THIS MORNING. THIS IS BASICALLY ROUNDING THE BASE OF WHAT REALLY IS A MASSIVE LONGWAVE TROUGH ACROSS CENTRAL NORTH AMERICA...WITH AN IMPRESSIVE JANUARY-LIKE -40C OBSERVED AT 500MB LAST NIGHT ALL THE WAY SOUTH TO CYQD IN SOUTHERN MANITOBA. GIVEN THE UPPER FLOW...PV ANOMALY EVOLUTION...AND MID-LEVEL BAROCLINICITY...THIS WAVE IS FORECAST TO TURN MORE NORTHEAST THIS AFTERNOON AND ADVANCE INTO CENTRAL AND NORTHERN IL/IN DURING THE MID-AFTERNOON INTO MID-EVE. THIS WILL BRING WITH IT FOCUSED OMEGA AND FRONTOGENETIC SUPPORTED UPWARD MOTION DURING THAT PERIOD AND WOULD EXPECT TO SEE MODERATE PRECIPITATION DEVELOPING FROM SOUTHWEST TO NORTHEAST ACROSS THE HEART OF THE FORECAST AREA...LIKELY REACHING THE CHICAGO AREA DURING THE 3-6 PM TIME. SO HAVE BUMPED UP POPS CONSIDERABLY. IN ADDITION...THE MID-LEVEL TEMPERATURES WILL CONTINUE TO COOL WITH THE FEATURE AND THE LOWER LEVELS THROUGH DIABATIC EFFECTS. ITS QUITE RARE TO SEE SNOW HERE DURING APRIL /ESPECIALLY MID-APRIL/ AFTERNOONS...BUT DO SEE PRECIPITATION STRUGGLING TO STAY AS RAIN GIVEN RAP AND NAM FORECAST THERMAL PROFILES AND JUST THE DEGREE OF FORCING. SO A QUICK TRANSITION TO A WET SNOW FROM NORTH TO SOUTH ACROSS THE CHICAGO METRO AREA IS FAVORED DURING THE RUSH HOUR...AND PROBABLY THE FIRST HALF AT THAT. SUPPRESSION ALOFT FOLLOWS BEHIND THE UPPER WAVE LATE THIS EVE INTO OVERNIGHT AND WILL END THE SNOW /FOR GOOD FINALLY?/. ANY INITIAL SNOW WILL STRUGGLE TO STICK WITH 4-INCH SOIL TEMPS AROUND 50 DEGREES AND THE WET GROUND IN PLACES...BUT THE FORCING LIKELY IS TO WIN OUT FOR A LIGHT COATING ESPECIALLY ON GRASSY SURFACES. THIS IS PRESENTLY MOST FAVORED ALONG AND SOUTH OF A MENDOTA TO CHICAGO LINE...AS THAT IS THE AREA THAT LOOKS TO HAVE THE BEST FORCING AS THE TEMPERATURES COOL LATE IN THE DAY AND THIS EVE. THERE IS UNCERTAINTY WITH THIS PLACEMENT THOUGH...AS SOME MESOSCALE PARAMETERS ARE AT PLAY. ACCUMULATION AROUND AN INCH TO A LITTLE OVER MAY OCCUR IN THE AREA THAT DOES END UP SEEING THE BETTER FORCING THANKS TO DECENT SNOWFALL RATES AT TIMES. TEMPERATURES WILL HOLD FLAT-LINE AND EVEN DROP DURING THE AFTERNOON AS PRECIPITATION EVOLVES INTO THE REGION. COLD AIR ADVECTION CONTINUES TONIGHT WITH 850MB TEMPS DROPPING TO THE -10C ARENA. THIS WILL SUPPORT CHICAGO CLOSING IN ON A RECORD LOW FOR TONIGHT /CALENDAR DAY OF APRIL 15/. SEE CLIMATE SECTION BELOW FOR MORE. TUESDAY THROUGH THURSDAY... NOT TOO MANY CHANGES MADE TO THIS PERIOD WHICH LOOKS MAINLY QUIET. A CHILLY TUESDAY IS EXPECTED WITH THE LOW STARTING POINT AND THE 850-925MB THERMAL TROUGH OVER US IN THE MORNING. A LAKE BREEZE DEVELOPING THAT AFTERNOON WILL NOT HELP MATTERS EITHER. UPPER 30S TO MID 40S ARE EXPECTED FROM NEAR THE LAKE TO THE REST OF THE FORECAST AREA ON TUESDAY AFTERNOON. UNCERTAINTY EXISTS ON CLOUD COVER FOR MUCH OF THIS TIME RANGE AND THAT WILL OF COURSE IMPACT TEMPERATURES GREATLY. THIS INCLUDES HIGH CLOUDS TUESDAY NIGHT WHICH COULD PREVENT ANOTHER CHILLY NIGHT IN THE 20S...AND HAVE INCHED UP FORECAST VALUES SOME FAVORING A LITTLE MORE CLOUD COVER AT THIS TIME. IN ADDITION...THURSDAY INTO THURSDAY NIGHT LOOKS TO HAVE SOUTHERLY FLOW AND THERE ARE INDICATIONS OF LOW CLOUDS MOVING NORTH DURING THAT TIME FRAME. WILL NEED TO WAIT TO THAT PERIOD GETS CLOSER TO GET TOO FANCY WITH TEMPERATURES BUT HAVE GONE WITH A BLEND OF GUIDANCE INCLUDING THE PREVIOUS FORECAST AT THIS TIME FOR TEMPS DURING THURSDAY. FRIDAY AND BEYOND... GIVEN A MASSIVE UPPER RIDGE OVER THE WESTERN TO NORTHERN ATLANTIC...ANY SHARP ADVANCEMENT OF AN UPPER RIDGE FROM THE WEST INTO OUR AREA LOOKS TO BE HALTED/SLOWED. WE WILL BUILD HEIGHTS GRADUALLY THURSDAY BUT MODEL GUIDANCE IS IN DECENT AGREEMENT WITH ADVANCING A PACIFIC SYSTEM INTO THE REGION BY FRIDAY AND PRODUCING LIKELY RAIN IN THE GENERAL REGION. THIS COULD SLOW GIVEN THE BACKED UP FLOW TO OUR EAST...AND HAVE TAKEN THAT INTO ACCOUNT FROM A SMART BLEND OF GUIDANCE POPS...SLOWING THEM SOMEWHAT. ONCE AGAIN TEMPERATURES ON FRIDAY DEPEND HEAVILY ON WHETHER OR NOT CLOUDS AND PRECIP ARE AS PROLIFIC AS MOST GUIDANCE IS INDICATING NOW. GRADUALLY BUILDING HEIGHTS SHOULD FOLLOW THAT SYSTEM DEPARTURE SOMETIME LATE FRIDAY/THIS WEEKEND. MTF && .CLIMATE... 625 AM CDT THE FOLLOWING ARE THE LAST APRIL DATES AND AMOUNTS OF ACCUMULATING SNOWFALL: CHICAGO: APRIL 18 2011 (0.6 IN.) ROCKFORD: APRIL 5 2009 (0.2 IN.) THE FOLLOWING ARE RECORD LOWS FOR THE MORNING OF APRIL 15TH. THE CHICAGO ONE IS THE MOST LIKELY IN JEOPARDY. CHICAGO: 25 (1943) ROCKFORD: 16 (1928) MTF && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 16Z... * MVFR CIGS...LOWERING BACK TOWARDS LOW END MVFR LATER THIS AFTERNOON. * GUSTY N WINDS THROUGH THE DAY...POSSIBLY TURNING NNE BY EARLY AFTERNOON. * SNOW OVERSPREADING THE TERMINALS MID AFTERNOON WITH MINOR ACCUMULATIONS. BMD //DISCUSSION...UPDATED 12Z... A COLD FRONT IS WORKING ACROSS NORTHEASTERN ILLINOIS EARLY THIS MORNING WITH WINDS TURNING SHARPLY TO THE NNW WITH GUSTS TO AROUND 30 KT. AREA OBSERVATIONS SHOW A NARROW CORRIDOR OF IFR CIGS IN THE VICINITY OF THE FRONT...WHICH HAS BEEN SHRINKING OVERNIGHT WITH PRIMARILY MVFR CIGS EXPECTED THIS MORNING. PRECIP HAS ALSO DWINDLED AND EXPECTED A COUPLE HOURS OF LIGHT RAIN/DRIZZLE EARLY THIS MORNING THEN DRY CONDITIONS SHOULD PREVAIL THROUGH AROUND MID AFTERNOON. AT THAT TIME...AN UPPER LEVEL DISTURBANCE WILL MOVE ACROSS THE AREA WITH PRECIP OVERSPREADING THE AREA FROM THE SOUTHWEST. RFD MAY BE CLIPPED BY THIS PRECIP...BUT THE CHICAGO TERMINALS ARE EXPECTED TO TAKE A MORE DIRECT SHOT. AT THE ONSET...TEMPERATURES MAY BE WARM ENOUGH FOR A MIX OF RAIN AND SNOW...PARTICULARLY AT MDW AND GYY...BUT THE COLUMN WILL COOL AND EXPECT A TRANSITION TO ALL SNOW WITH MINOR ACCUMULATIONS POSSIBLE...ESPECIALLY ON GRASSY SURFACES... OF UP TO AROUND AND INCH. WINDS SHOULD PRIMARILY REMAIN IN THE 330-360 DIRECTION TODAY WITH GUSTS AROUND 30 KT THIS MORNING VERY SLOWLY TAPERING THROUGH THE DAY. BMD //ORD AND MDW CONFIDENCE...UPDATED 16Z... * MEDIUM HIGH CONFIDENCE WITH CIGS. * MEDIUM-HIGH CONFIDENCE IN WIND DIRECTION/SPEED. * MEDIUM-HIGH CONFIDENCE IN SNOW TIMING THIS AFTERNOON. BMD //OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z... TUESDAY NIGHT...VFR. WEDNESDAY...VFR. THURSDAY...VFR. FRIDAY...CHC RAIN. MVFR/IFR PSBL. SATURDAY...SLT CHC RAIN. MVFR/IFR PSBL. SUNDAY...CHC RAIN. MVFR/IFR PSBL. BMD && .MARINE... 240 AM CDT LOW PRESSURE IS MOVING ACROSS FAR SOUTHERN LAKE MICHIGAN EARLY THIS MORNING WITH GALE FORCE NORTHERLY WINDS OVERSPREADING THE LAKE BEHIND THE LOW AS IT BEGINS TO DEPART EAST. GALES ARE EXPECTED TO PERSIST THROUGH THE AFTERNOON...THEN SHOULD VERY GRADUALLY DIMINISH TO AROUND 30 KT THIS EVENING AND TONIGHT. FOG THAT WAS IN PLACE NEAR THE FRONTAL BOUNDARY ACROSS FAR SOUTHERN LAKE MICHIGAN SHOULD DIMINISH AS THE NORTHERLY WINDS OVERSPREAD THE LAKE. RIDGING WILL TRANSLATE ACROSS LAKE MICHIGAN LATE IN THE DAY TUESDAY ALLOWING WINDS TO BRIEFLY SUBSIDE...BUT SOUTH/SOUTHEAST WINDS PICK UP AGAIN ON WEDNESDAY AS ANOTHER LOW DEVELOPS OVER THE CENTRAL PLAINS. BMD && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565- LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868- LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 3 PM MONDAY. GALE WARNING...NEARSHORE WATERS UNTIL 4 PM MONDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
921 AM CDT MON APR 14 2014 .DISCUSSION... 330 AM CDT THE INFAMOUS WINTER 2013-2014 BEGAN IN OCTOBER WITH SNOW AND TODAY IT WANTS TO MAKE SURE IT INCLUDES APRIL TO ENCOMPASS SEVEN MONTHS. THIS UNFRIENDLY VERY LATE VISIT FROM WINTER WAS THE PRIMARY FORECAST CHALLENGE...ALONG WITH TEMPERATURES THROUGHOUT THE WEEK AS WE WILL BE WELL BELOW NORMAL TO START THIS WEEK...POTENTIALLY TO RECORD LEVELS TONIGHT. THIS MORNING... THE 995MB SURFACE LOW IS PASSING OVER THE NORTH METRO OF CHICAGO EARLY THIS MORNING AND 30 MILES EITHER SIDE OF ITS PATH SEPARATES 60S AND CONVECTIVE RAIN SHOWERS AND 30S AND DEFORMATION SNOW. THE DEEPENING AND CLASSIC LOOKING UPPER WAVE WITH THIS IS ADVANCING NORTHEAST FROM SOUTHWEST WI AND ITS DEFORMATION AND WRAPAROUND MOISTURE WILL ONLY GRAZE THE AREA THIS MORNING. WHILE A MIX WITH WET SNOW IS PROBABLE OVER PARTS OF NORTH CENTRAL IL...THE FORCING FOR MODEST SNOW RATES IS LIKELY TO REMAIN TO THE NORTH IN THE A.M. HOURS SO NOT EXPECTING ANY ACCUMULATIONS PRIOR TO NOON. WINDS ON THE BACKSIDE OF THE LOW THIS MORNING LOOK TO GUST TO AROUND 40 MPH AT TIMES...WHICH BESIDES ADDING QUITE A CHILL TO THE AIR...MAY REDUCE VISIBILITY UP BY ROCKFORD IF SNOW CAN MATERIALIZE THIS MORNING. OTHERWISE THOUGH...IMPACTS LOOK MINOR DURING THIS PERIOD. THIS AFTERNOON AND TONIGHT... A SECOND WELL-DEFINED UPPER CIRCULATION IS ADVANCING EASTWARD INTO THE CENTRAL PLAINS EARLY THIS MORNING. THIS IS BASICALLY ROUNDING THE BASE OF WHAT REALLY IS A MASSIVE LONGWAVE TROUGH ACROSS CENTRAL NORTH AMERICA...WITH AN IMPRESSIVE JANUARY-LIKE -40C OBSERVED AT 500MB LAST NIGHT ALL THE WAY SOUTH TO CYQD IN SOUTHERN MANITOBA. GIVEN THE UPPER FLOW...PV ANOMALY EVOLUTION...AND MID-LEVEL BAROCLINICITY...THIS WAVE IS FORECAST TO TURN MORE NORTHEAST THIS AFTERNOON AND ADVANCE INTO CENTRAL AND NORTHERN IL/IN DURING THE MID-AFTERNOON INTO MID-EVE. THIS WILL BRING WITH IT FOCUSED OMEGA AND FRONTOGENETIC SUPPORTED UPWARD MOTION DURING THAT PERIOD AND WOULD EXPECT TO SEE MODERATE PRECIPITATION DEVELOPING FROM SOUTHWEST TO NORTHEAST ACROSS THE HEART OF THE FORECAST AREA...LIKELY REACHING THE CHICAGO AREA DURING THE 3-6 PM TIME. SO HAVE BUMPED UP POPS CONSIDERABLY. IN ADDITION...THE MID-LEVEL TEMPERATURES WILL CONTINUE TO COOL WITH THE FEATURE AND THE LOWER LEVELS THROUGH DIABATIC EFFECTS. ITS QUITE RARE TO SEE SNOW HERE DURING APRIL /ESPECIALLY MID-APRIL/ AFTERNOONS...BUT DO SEE PRECIPITATION STRUGGLING TO STAY AS RAIN GIVEN RAP AND NAM FORECAST THERMAL PROFILES AND JUST THE DEGREE OF FORCING. SO A QUICK TRANSITION TO A WET SNOW FROM NORTH TO SOUTH ACROSS THE CHICAGO METRO AREA IS FAVORED DURING THE RUSH HOUR...AND PROBABLY THE FIRST HALF AT THAT. SUPPRESSION ALOFT FOLLOWS BEHIND THE UPPER WAVE LATE THIS EVE INTO OVERNIGHT AND WILL END THE SNOW /FOR GOOD FINALLY?/. ANY INITIAL SNOW WILL STRUGGLE TO STICK WITH 4-INCH SOIL TEMPS AROUND 50 DEGREES AND THE WET GROUND IN PLACES...BUT THE FORCING LIKELY IS TO WIN OUT FOR A LIGHT COATING ESPECIALLY ON GRASSY SURFACES. THIS IS PRESENTLY MOST FAVORED ALONG AND SOUTH OF A MENDOTA TO CHICAGO LINE...AS THAT IS THE AREA THAT LOOKS TO HAVE THE BEST FORCING AS THE TEMPERATURES COOL LATE IN THE DAY AND THIS EVE. THERE IS UNCERTAINTY WITH THIS PLACEMENT THOUGH...AS SOME MESOSCALE PARAMETERS ARE AT PLAY. ACCUMULATION AROUND AN INCH TO A LITTLE OVER MAY OCCUR IN THE AREA THAT DOES END UP SEEING THE BETTER FORCING THANKS TO DECENT SNOWFALL RATES AT TIMES. TEMPERATURES WILL HOLD FLAT-LINE AND EVEN DROP DURING THE AFTERNOON AS PRECIPITATION EVOLVES INTO THE REGION. COLD AIR ADVECTION CONTINUES TONIGHT WITH 850MB TEMPS DROPPING TO THE -10C ARENA. THIS WILL SUPPORT CHICAGO CLOSING IN ON A RECORD LOW FOR TONIGHT /CALENDAR DAY OF APRIL 15/. SEE CLIMATE SECTION BELOW FOR MORE. TUESDAY THROUGH THURSDAY... NOT TOO MANY CHANGES MADE TO THIS PERIOD WHICH LOOKS MAINLY QUIET. A CHILLY TUESDAY IS EXPECTED WITH THE LOW STARTING POINT AND THE 850-925MB THERMAL TROUGH OVER US IN THE MORNING. A LAKE BREEZE DEVELOPING THAT AFTERNOON WILL NOT HELP MATTERS EITHER. UPPER 30S TO MID 40S ARE EXPECTED FROM NEAR THE LAKE TO THE REST OF THE FORECAST AREA ON TUESDAY AFTERNOON. UNCERTAINTY EXISTS ON CLOUD COVER FOR MUCH OF THIS TIME RANGE AND THAT WILL OF COURSE IMPACT TEMPERATURES GREATLY. THIS INCLUDES HIGH CLOUDS TUESDAY NIGHT WHICH COULD PREVENT ANOTHER CHILLY NIGHT IN THE 20S...AND HAVE INCHED UP FORECAST VALUES SOME FAVORING A LITTLE MORE CLOUD COVER AT THIS TIME. IN ADDITION...THURSDAY INTO THURSDAY NIGHT LOOKS TO HAVE SOUTHERLY FLOW AND THERE ARE INDICATIONS OF LOW CLOUDS MOVING NORTH DURING THAT TIME FRAME. WILL NEED TO WAIT TO THAT PERIOD GETS CLOSER TO GET TOO FANCY WITH TEMPERATURES BUT HAVE GONE WITH A BLEND OF GUIDANCE INCLUDING THE PREVIOUS FORECAST AT THIS TIME FOR TEMPS DURING THURSDAY. FRIDAY AND BEYOND... GIVEN A MASSIVE UPPER RIDGE OVER THE WESTERN TO NORTHERN ATLANTIC...ANY SHARP ADVANCEMENT OF AN UPPER RIDGE FROM THE WEST INTO OUR AREA LOOKS TO BE HALTED/SLOWED. WE WILL BUILD HEIGHTS GRADUALLY THURSDAY BUT MODEL GUIDANCE IS IN DECENT AGREEMENT WITH ADVANCING A PACIFIC SYSTEM INTO THE REGION BY FRIDAY AND PRODUCING LIKELY RAIN IN THE GENERAL REGION. THIS COULD SLOW GIVEN THE BACKED UP FLOW TO OUR EAST...AND HAVE TAKEN THAT INTO ACCOUNT FROM A SMART BLEND OF GUIDANCE POPS...SLOWING THEM SOMEWHAT. ONCE AGAIN TEMPERATURES ON FRIDAY DEPEND HEAVILY ON WHETHER OR NOT CLOUDS AND PRECIP ARE AS PROLIFIC AS MOST GUIDANCE IS INDICATING NOW. GRADUALLY BUILDING HEIGHTS SHOULD FOLLOW THAT SYSTEM DEPARTURE SOMETIME LATE FRIDAY/THIS WEEKEND. MTF && .CLIMATE... 625 AM CDT THE FOLLOWING ARE THE LAST APRIL DATES AND AMOUNTS OF ACCUMULATING SNOWFALL: CHICAGO: APRIL 18 2011 (0.6 IN.) ROCKFORD: APRIL 5 2009 (0.2 IN.) THE FOLLOWING ARE RECORD LOWS FOR THE MORNING OF APRIL 15TH. THE CHICAGO ONE IS THE MOST LIKELY IN JEOPARDY. CHICAGO: 25 (1943) ROCKFORD: 16 (1928) MTF && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 14Z... * RAIN/SNOW/SLEET MIX EXITING THIS NEXT HALF HOUR...WITH MVFR CIGS REMAINING. * GUSTY N WINDS THROUGH THE DAY...LIKELY TURNING NNE BY EARLY AFTERNOON. * SNOW OVERSPREADING THE TERMINALS MID AFTERNOON WITH MINOR ACCUMULATIONS. BMD //DISCUSSION...UPDATED 12Z... A COLD FRONT IS WORKING ACROSS NORTHEASTERN ILLINOIS EARLY THIS MORNING WITH WINDS TURNING SHARPLY TO THE NNW WITH GUSTS TO AROUND 30 KT. AREA OBSERVATIONS SHOW A NARROW CORRIDOR OF IFR CIGS IN THE VICINITY OF THE FRONT...WHICH HAS BEEN SHRINKING OVERNIGHT WITH PRIMARILY MVFR CIGS EXPECTED THIS MORNING. PRECIP HAS ALSO DWINDLED AND EXPECTED A COUPLE HOURS OF LIGHT RAIN/DRIZZLE EARLY THIS MORNING THEN DRY CONDITIONS SHOULD PREVAIL THROUGH AROUND MID AFTERNOON. AT THAT TIME...AN UPPER LEVEL DISTURBANCE WILL MOVE ACROSS THE AREA WITH PRECIP OVERSPREADING THE AREA FROM THE SOUTHWEST. RFD MAY BE CLIPPED BY THIS PRECIP...BUT THE CHICAGO TERMINALS ARE EXPECTED TO TAKE A MORE DIRECT SHOT. AT THE ONSET...TEMPERATURES MAY BE WARM ENOUGH FOR A MIX OF RAIN AND SNOW...PARTICULARLY AT MDW AND GYY...BUT THE COLUMN WILL COOL AND EXPECT A TRANSITION TO ALL SNOW WITH MINOR ACCUMULATIONS POSSIBLE...ESPECIALLY ON GRASSY SURFACES... OF UP TO AROUND AND INCH. WINDS SHOULD PRIMARILY REMAIN IN THE 330-360 DIRECTION TODAY WITH GUSTS AROUND 30 KT THIS MORNING VERY SLOWLY TAPERING THROUGH THE DAY. BMD //ORD AND MDW CONFIDENCE...UPDATED 14Z... * HIGH CONFIDENCE IN PRECIP TIMING AND CIG/VIS TRENDS. * MEDIUM-HIGH CONFIDENCE IN WIND DIRECTION/SPEED. * MEDIUM-HIGH CONFIDENCE IN SNOW TIMING THIS AFTERNOON. BMD //OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z... TUESDAY NIGHT...VFR. WEDNESDAY...VFR. THURSDAY...VFR. FRIDAY...CHC RAIN. MVFR/IFR PSBL. SATURDAY...SLT CHC RAIN. MVFR/IFR PSBL. SUNDAY...CHC RAIN. MVFR/IFR PSBL. BMD && .MARINE... 240 AM CDT LOW PRESSURE IS MOVING ACROSS FAR SOUTHERN LAKE MICHIGAN EARLY THIS MORNING WITH GALE FORCE NORTHERLY WINDS OVERSPREADING THE LAKE BEHIND THE LOW AS IT BEGINS TO DEPART EAST. GALES ARE EXPECTED TO PERSIST THROUGH THE AFTERNOON...THEN SHOULD VERY GRADUALLY DIMINISH TO AROUND 30 KT THIS EVENING AND TONIGHT. FOG THAT WAS IN PLACE NEAR THE FRONTAL BOUNDARY ACROSS FAR SOUTHERN LAKE MICHIGAN SHOULD DIMINISH AS THE NORTHERLY WINDS OVERSPREAD THE LAKE. RIDGING WILL TRANSLATE ACROSS LAKE MICHIGAN LATE IN THE DAY TUESDAY ALLOWING WINDS TO BRIEFLY SUBSIDE...BUT SOUTH/SOUTHEAST WINDS PICK UP AGAIN ON WEDNESDAY AS ANOTHER LOW DEVELOPS OVER THE CENTRAL PLAINS. BMD && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565- LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868- LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 3 PM MONDAY. GALE WARNING...NEARSHORE WATERS UNTIL 4 PM MONDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
633 AM CDT MON APR 14 2014 .DISCUSSION... 330 AM CDT THE INFAMOUS WINTER 2013-2014 BEGAN IN OCTOBER WITH SNOW AND TODAY IT WANTS TO MAKE SURE IT INCLUDES APRIL TO ENCOMPASS SEVEN MONTHS. THIS UNFRIENDLY VERY LATE VISIT FROM WINTER WAS THE PRIMARY FORECAST CHALLENGE...ALONG WITH TEMPERATURES THROUGHOUT THE WEEK AS WE WILL BE WELL BELOW NORMAL TO START THIS WEEK...POTENTIALLY TO RECORD LEVELS TONIGHT. THIS MORNING... THE 995MB SURFACE LOW IS PASSING OVER THE NORTH METRO OF CHICAGO EARLY THIS MORNING AND 30 MILES EITHER SIDE OF ITS PATH SEPARATES 60S AND CONVECTIVE RAIN SHOWERS AND 30S AND DEFORMATION SNOW. THE DEEPENING AND CLASSIC LOOKING UPPER WAVE WITH THIS IS ADVANCING NORTHEAST FROM SOUTHWEST WI AND ITS DEFORMATION AND WRAPAROUND MOISTURE WILL ONLY GRAZE THE AREA THIS MORNING. WHILE A MIX WITH WET SNOW IS PROBABLE OVER PARTS OF NORTH CENTRAL IL...THE FORCING FOR MODEST SNOW RATES IS LIKELY TO REMAIN TO THE NORTH IN THE A.M. HOURS SO NOT EXPECTING ANY ACCUMULATIONS PRIOR TO NOON. WINDS ON THE BACKSIDE OF THE LOW THIS MORNING LOOK TO GUST TO AROUND 40 MPH AT TIMES...WHICH BESIDES ADDING QUITE A CHILL TO THE AIR...MAY REDUCE VISIBILITY UP BY ROCKFORD IF SNOW CAN MATERIALIZE THIS MORNING. OTHERWISE THOUGH...IMPACTS LOOK MINOR DURING THIS PERIOD. THIS AFTERNOON AND TONIGHT... A SECOND WELL-DEFINED UPPER CIRCULATION IS ADVANCING EASTWARD INTO THE CENTRAL PLAINS EARLY THIS MORNING. THIS IS BASICALLY ROUNDING THE BASE OF WHAT REALLY IS A MASSIVE LONGWAVE TROUGH ACROSS CENTRAL NORTH AMERICA...WITH AN IMPRESSIVE JANUARY-LIKE -40C OBSERVED AT 500MB LAST NIGHT ALL THE WAY SOUTH TO CYQD IN SOUTHERN MANITOBA. GIVEN THE UPPER FLOW...PV ANOMALY EVOLUTION...AND MID-LEVEL BAROCLINICITY...THIS WAVE IS FORECAST TO TURN MORE NORTHEAST THIS AFTERNOON AND ADVANCE INTO CENTRAL AND NORTHERN IL/IN DURING THE MID-AFTERNOON INTO MID-EVE. THIS WILL BRING WITH IT FOCUSED OMEGA AND FRONTOGENETIC SUPPORTED UPWARD MOTION DURING THAT PERIOD AND WOULD EXPECT TO SEE MODERATE PRECIPITATION DEVELOPING FROM SOUTHWEST TO NORTHEAST ACROSS THE HEART OF THE FORECAST AREA...LIKELY REACHING THE CHICAGO AREA DURING THE 3-6 PM TIME. SO HAVE BUMPED UP POPS CONSIDERABLY. IN ADDITION...THE MID-LEVEL TEMPERATURES WILL CONTINUE TO COOL WITH THE FEATURE AND THE LOWER LEVELS THROUGH DIABATIC EFFECTS. ITS QUITE RARE TO SEE SNOW HERE DURING APRIL /ESPECIALLY MID-APRIL/ AFTERNOONS...BUT DO SEE PRECIPITATION STRUGGLING TO STAY AS RAIN GIVEN RAP AND NAM FORECAST THERMAL PROFILES AND JUST THE DEGREE OF FORCING. SO A QUICK TRANSITION TO A WET SNOW FROM NORTH TO SOUTH ACROSS THE CHICAGO METRO AREA IS FAVORED DURING THE RUSH HOUR...AND PROBABLY THE FIRST HALF AT THAT. SUPPRESSION ALOFT FOLLOWS BEHIND THE UPPER WAVE LATE THIS EVE INTO OVERNIGHT AND WILL END THE SNOW /FOR GOOD FINALLY?/. ANY INITIAL SNOW WILL STRUGGLE TO STICK WITH 4-INCH SOIL TEMPS AROUND 50 DEGREES AND THE WET GROUND IN PLACES...BUT THE FORCING LIKELY IS TO WIN OUT FOR A LIGHT COATING ESPECIALLY ON GRASSY SURFACES. THIS IS PRESENTLY MOST FAVORED ALONG AND SOUTH OF A MENDOTA TO CHICAGO LINE...AS THAT IS THE AREA THAT LOOKS TO HAVE THE BEST FORCING AS THE TEMPERATURES COOL LATE IN THE DAY AND THIS EVE. THERE IS UNCERTAINTY WITH THIS PLACEMENT THOUGH...AS SOME MESOSCALE PARAMETERS ARE AT PLAY. ACCUMULATION AROUND AN INCH TO A LITTLE OVER MAY OCCUR IN THE AREA THAT DOES END UP SEEING THE BETTER FORCING THANKS TO DECENT SNOWFALL RATES AT TIMES. TEMPERATURES WILL HOLD FLAT-LINE AND EVEN DROP DURING THE AFTERNOON AS PRECIPITATION EVOLVES INTO THE REGION. COLD AIR ADVECTION CONTINUES TONIGHT WITH 850MB TEMPS DROPPING TO THE -10C ARENA. THIS WILL SUPPORT CHICAGO CLOSING IN ON A RECORD LOW FOR TONIGHT /CALENDAR DAY OF APRIL 15/. SEE CLIMATE SECTION BELOW FOR MORE. TUESDAY THROUGH THURSDAY... NOT TOO MANY CHANGES MADE TO THIS PERIOD WHICH LOOKS MAINLY QUIET. A CHILLY TUESDAY IS EXPECTED WITH THE LOW STARTING POINT AND THE 850-925MB THERMAL TROUGH OVER US IN THE MORNING. A LAKE BREEZE DEVELOPING THAT AFTERNOON WILL NOT HELP MATTERS EITHER. UPPER 30S TO MID 40S ARE EXPECTED FROM NEAR THE LAKE TO THE REST OF THE FORECAST AREA ON TUESDAY AFTERNOON. UNCERTAINTY EXISTS ON CLOUD COVER FOR MUCH OF THIS TIME RANGE AND THAT WILL OF COURSE IMPACT TEMPERATURES GREATLY. THIS INCLUDES HIGH CLOUDS TUESDAY NIGHT WHICH COULD PREVENT ANOTHER CHILLY NIGHT IN THE 20S...AND HAVE INCHED UP FORECAST VALUES SOME FAVORING A LITTLE MORE CLOUD COVER AT THIS TIME. IN ADDITION...THURSDAY INTO THURSDAY NIGHT LOOKS TO HAVE SOUTHERLY FLOW AND THERE ARE INDICATIONS OF LOW CLOUDS MOVING NORTH DURING THAT TIME FRAME. WILL NEED TO WAIT TO THAT PERIOD GETS CLOSER TO GET TOO FANCY WITH TEMPERATURES BUT HAVE GONE WITH A BLEND OF GUIDANCE INCLUDING THE PREVIOUS FORECAST AT THIS TIME FOR TEMPS DURING THURSDAY. FRIDAY AND BEYOND... GIVEN A MASSIVE UPPER RIDGE OVER THE WESTERN TO NORTHERN ATLANTIC...ANY SHARP ADVANCEMENT OF AN UPPER RIDGE FROM THE WEST INTO OUR AREA LOOKS TO BE HALTED/SLOWED. WE WILL BUILD HEIGHTS GRADUALLY THURSDAY BUT MODEL GUIDANCE IS IN DECENT AGREEMENT WITH ADVANCING A PACIFIC SYSTEM INTO THE REGION BY FRIDAY AND PRODUCING LIKELY RAIN IN THE GENERAL REGION. THIS COULD SLOW GIVEN THE BACKED UP FLOW TO OUR EAST...AND HAVE TAKEN THAT INTO ACCOUNT FROM A SMART BLEND OF GUIDANCE POPS...SLOWING THEM SOMEWHAT. ONCE AGAIN TEMPERATURES ON FRIDAY DEPEND HEAVILY ON WHETHER OR NOT CLOUDS AND PRECIP ARE AS PROLIFIC AS MOST GUIDANCE IS INDICATING NOW. GRADUALLY BUILDING HEIGHTS SHOULD FOLLOW THAT SYSTEM DEPARTURE SOMETIME LATE FRIDAY/THIS WEEKEND. MTF && .CLIMATE... 625 AM CDT THE FOLLOWING ARE THE LAST APRIL DATES AND AMOUNTS OF ACCUMULATING SNOWFALL: CHICAGO: APRIL 18 2011 (0.6 IN.) ROCKFORD: APRIL 5 2009 (0.2 IN.) THE FOLLOWING ARE RECORD LOWS FOR THE MORNING OF APRIL 15TH. THE CHICAGO ONE IS THE MOST LIKELY IN JEOPARDY. CHICAGO: 25 (1943) ROCKFORD: 16 (1928) MTF && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 12Z... * FRONT SWEEPING ACROSS THE AREA WITH RAIN/IFR IN THE VICINITY OF THE FRONT...THEN PRIMARILY MVFR CIGS. * GUSTY NNW WINDS THROUGH THE DAY. * SNOW OVERSPREADING THE TERMINALS MID AFTERNOON WITH MINOR ACCUMULATIONS. BMD //DISCUSSION...UPDATED 12Z... A COLD FRONT IS WORKING ACROSS NORTHEASTERN ILLINOIS EARLY THIS MORNING WITH WINDS TURNING SHARPLY TO THE NNW WITH GUSTS TO AROUND 30 KT. AREA OBSERVATIONS SHOW A NARROW CORRIDOR OF IFR CIGS IN THE VICINITY OF THE FRONT...WHICH HAS BEEN SHRINKING OVERNIGHT WITH PRIMARILY MVFR CIGS EXPECTED THIS MORNING. PRECIP HAS ALSO DWINDLED AND EXPECTED A COUPLE HOURS OF LIGHT RAIN/DRIZZLE EARLY THIS MORNING THEN DRY CONDITIONS SHOULD PREVAIL THROUGH AROUND MID AFTERNOON. AT THAT TIME...AN UPPER LEVEL DISTURBANCE WILL MOVE ACROSS THE AREA WITH PRECIP OVERSPREADING THE AREA FROM THE SOUTHWEST. RFD MAY BE CLIPPED BY THIS PRECIP...BUT THE CHICAGO TERMINALS ARE EXPECTED TO TAKE A MORE DIRECT SHOT. AT THE ONSET...TEMPERATURES MAY BE WARM ENOUGH FOR A MIX OF RAIN AND SNOW...PARTICULARLY AT MDW AND GYY...BUT THE COLUMN WILL COOL AND EXPECT A TRANSITION TO ALL SNOW WITH MINOR ACCUMULATIONS POSSIBLE...ESPECIALLY ON GRASSY SURFACES... OF UP TO AROUND AND INCH. WINDS SHOULD PRIMARILY REMAIN IN THE 330-360 DIRECTION TODAY WITH GUSTS AROUND 30 KT THIS MORNING VERY SLOWLY TAPERING THROUGH THE DAY. BMD //ORD AND MDW CONFIDENCE...UPDATED 12Z... * MEDIUM CONFIDENCE IN PRECIP TIMING AND CIG/VIS TRENDS. * MEDIUM-HIGH CONFIDENCE IN WIND DIRECTION/SPEED. * MEDIUM-HIGH CONFIDENCE IN SNOW TIMING THIS AFTERNOON. BMD //OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z... TUESDAY NIGHT...VFR. WEDNESDAY...VFR. THURSDAY...VFR. FRIDAY...CHC RAIN. MVFR/IFR PSBL. SATURDAY...SLT CHC RAIN. MVFR/IFR PSBL. SUNDAY...CHC RAIN. MVFR/IFR PSBL. BMD && .MARINE... 240 AM CDT LOW PRESSURE IS MOVING ACROSS FAR SOUTHERN LAKE MICHIGAN EARLY THIS MORNING WITH GALE FORCE NORTHERLY WINDS OVERSPREADING THE LAKE BEHIND THE LOW AS IT BEGINS TO DEPART EAST. GALES ARE EXPECTED TO PERSIST THROUGH THE AFTERNOON...THEN SHOULD VERY GRADUALLY DIMINISH TO AROUND 30 KT THIS EVENING AND TONIGHT. FOG THAT WAS IN PLACE NEAR THE FRONTAL BOUNDARY ACROSS FAR SOUTHERN LAKE MICHIGAN SHOULD DIMINISH AS THE NORTHERLY WINDS OVERSPREAD THE LAKE. RIDGING WILL TRANSLATE ACROSS LAKE MICHIGAN LATE IN THE DAY TUESDAY ALLOWING WINDS TO BRIEFLY SUBSIDE...BUT SOUTH/SOUTHEAST WINDS PICK UP AGAIN ON WEDNESDAY AS ANOTHER LOW DEVELOPS OVER THE CENTRAL PLAINS. BMD && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565- LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868- LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 3 PM MONDAY. GALE WARNING...NEARSHORE WATERS UNTIL 4 PM MONDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
627 AM CDT MON APR 14 2014 .DISCUSSION... 330 AM CDT THE INFAMOUS WINTER 2013-2014 BEGAN IN OCTOBER WITH SNOW AND TODAY IT WANTS TO MAKE SURE IT INCLUDES APRIL TO ENCOMPASS SEVEN MONTHS. THIS UNFRIENDLY VERY LATE VISIT FROM WINTER WAS THE PRIMARY FORECAST CHALLENGE...ALONG WITH TEMPERATURES THROUGHOUT THE WEEK AS WE WILL BE WELL BELOW NORMAL TO START THIS WEEK...POTENTIALLY TO RECORD LEVELS TONIGHT. THIS MORNING... THE 995MB SURFACE LOW IS PASSING OVER THE NORTH METRO OF CHICAGO EARLY THIS MORNING AND 30 MILES EITHER SIDE OF ITS PATH SEPARATES 60S AND CONVECTIVE RAIN SHOWERS AND 30S AND DEFORMATION SNOW. THE DEEPENING AND CLASSIC LOOKING UPPER WAVE WITH THIS IS ADVANCING NORTHEAST FROM SOUTHWEST WI AND ITS DEFORMATION AND WRAPAROUND MOISTURE WILL ONLY GRAZE THE AREA THIS MORNING. WHILE A MIX WITH WET SNOW IS PROBABLE OVER PARTS OF NORTH CENTRAL IL...THE FORCING FOR MODEST SNOW RATES IS LIKELY TO REMAIN TO THE NORTH IN THE A.M. HOURS SO NOT EXPECTING ANY ACCUMULATIONS PRIOR TO NOON. WINDS ON THE BACKSIDE OF THE LOW THIS MORNING LOOK TO GUST TO AROUND 40 MPH AT TIMES...WHICH BESIDES ADDING QUITE A CHILL TO THE AIR...MAY REDUCE VISIBILITY UP BY ROCKFORD IF SNOW CAN MATERIALIZE THIS MORNING. OTHERWISE THOUGH...IMPACTS LOOK MINOR DURING THIS PERIOD. THIS AFTERNOON AND TONIGHT... A SECOND WELL-DEFINED UPPER CIRCULATION IS ADVANCING EASTWARD INTO THE CENTRAL PLAINS EARLY THIS MORNING. THIS IS BASICALLY ROUNDING THE BASE OF WHAT REALLY IS A MASSIVE LONGWAVE TROUGH ACROSS CENTRAL NORTH AMERICA...WITH AN IMPRESSIVE JANUARY-LIKE -40C OBSERVED AT 500MB LAST NIGHT ALL THE WAY SOUTH TO CYQD IN SOUTHERN MANITOBA. GIVEN THE UPPER FLOW...PV ANOMALY EVOLUTION...AND MID-LEVEL BAROCLINICITY...THIS WAVE IS FORECAST TO TURN MORE NORTHEAST THIS AFTERNOON AND ADVANCE INTO CENTRAL AND NORTHERN IL/IN DURING THE MID-AFTERNOON INTO MID-EVE. THIS WILL BRING WITH IT FOCUSED OMEGA AND FRONTOGENETIC SUPPORTED UPWARD MOTION DURING THAT PERIOD AND WOULD EXPECT TO SEE MODERATE PRECIPITATION DEVELOPING FROM SOUTHWEST TO NORTHEAST ACROSS THE HEART OF THE FORECAST AREA...LIKELY REACHING THE CHICAGO AREA DURING THE 3-6 PM TIME. SO HAVE BUMPED UP POPS CONSIDERABLY. IN ADDITION...THE MID-LEVEL TEMPERATURES WILL CONTINUE TO COOL WITH THE FEATURE AND THE LOWER LEVELS THROUGH DIABATIC EFFECTS. ITS QUITE RARE TO SEE SNOW HERE DURING APRIL /ESPECIALLY MID-APRIL/ AFTERNOONS...BUT DO SEE PRECIPITATION STRUGGLING TO STAY AS RAIN GIVEN RAP AND NAM FORECAST THERMAL PROFILES AND JUST THE DEGREE OF FORCING. SO A QUICK TRANSITION TO A WET SNOW FROM NORTH TO SOUTH ACROSS THE CHICAGO METRO AREA IS FAVORED DURING THE RUSH HOUR...AND PROBABLY THE FIRST HALF AT THAT. SUPPRESSION ALOFT FOLLOWS BEHIND THE UPPER WAVE LATE THIS EVE INTO OVERNIGHT AND WILL END THE SNOW /FOR GOOD FINALLY?/. ANY INITIAL SNOW WILL STRUGGLE TO STICK WITH 4-INCH SOIL TEMPS AROUND 50 DEGREES AND THE WET GROUND IN PLACES...BUT THE FORCING LIKELY IS TO WIN OUT FOR A LIGHT COATING ESPECIALLY ON GRASSY SURFACES. THIS IS PRESENTLY MOST FAVORED ALONG AND SOUTH OF A MENDOTA TO CHICAGO LINE...AS THAT IS THE AREA THAT LOOKS TO HAVE THE BEST FORCING AS THE TEMPERATURES COOL LATE IN THE DAY AND THIS EVE. THERE IS UNCERTAINTY WITH THIS PLACEMENT THOUGH...AS SOME MESOSCALE PARAMETERS ARE AT PLAY. ACCUMULATION AROUND AN INCH TO A LITTLE OVER MAY OCCUR IN THE AREA THAT DOES END UP SEEING THE BETTER FORCING THANKS TO DECENT SNOWFALL RATES AT TIMES. TEMPERATURES WILL HOLD FLAT-LINE AND EVEN DROP DURING THE AFTERNOON AS PRECIPITATION EVOLVES INTO THE REGION. COLD AIR ADVECTION CONTINUES TONIGHT WITH 850MB TEMPS DROPPING TO THE -10C ARENA. THIS WILL SUPPORT CHICAGO CLOSING IN ON A RECORD LOW FOR TONIGHT /CALENDAR DAY OF APRIL 15/. SEE CLIMATE SECTION BELOW FOR MORE. TUESDAY THROUGH THURSDAY... NOT TOO MANY CHANGES MADE TO THIS PERIOD WHICH LOOKS MAINLY QUIET. A CHILLY TUESDAY IS EXPECTED WITH THE LOW STARTING POINT AND THE 850-925MB THERMAL TROUGH OVER US IN THE MORNING. A LAKE BREEZE DEVELOPING THAT AFTERNOON WILL NOT HELP MATTERS EITHER. UPPER 30S TO MID 40S ARE EXPECTED FROM NEAR THE LAKE TO THE REST OF THE FORECAST AREA ON TUESDAY AFTERNOON. UNCERTAINTY EXISTS ON CLOUD COVER FOR MUCH OF THIS TIME RANGE AND THAT WILL OF COURSE IMPACT TEMPERATURES GREATLY. THIS INCLUDES HIGH CLOUDS TUESDAY NIGHT WHICH COULD PREVENT ANOTHER CHILLY NIGHT IN THE 20S...AND HAVE INCHED UP FORECAST VALUES SOME FAVORING A LITTLE MORE CLOUD COVER AT THIS TIME. IN ADDITION...THURSDAY INTO THURSDAY NIGHT LOOKS TO HAVE SOUTHERLY FLOW AND THERE ARE INDICATIONS OF LOW CLOUDS MOVING NORTH DURING THAT TIME FRAME. WILL NEED TO WAIT TO THAT PERIOD GETS CLOSER TO GET TOO FANCY WITH TEMPERATURES BUT HAVE GONE WITH A BLEND OF GUIDANCE INCLUDING THE PREVIOUS FORECAST AT THIS TIME FOR TEMPS DURING THURSDAY. FRIDAY AND BEYOND... GIVEN A MASSIVE UPPER RIDGE OVER THE WESTERN TO NORTHERN ATLANTIC...ANY SHARP ADVANCEMENT OF AN UPPER RIDGE FROM THE WEST INTO OUR AREA LOOKS TO BE HALTED/SLOWED. WE WILL BUILD HEIGHTS GRADUALLY THURSDAY BUT MODEL GUIDANCE IS IN DECENT AGREEMENT WITH ADVANCING A PACIFIC SYSTEM INTO THE REGION BY FRIDAY AND PRODUCING LIKELY RAIN IN THE GENERAL REGION. THIS COULD SLOW GIVEN THE BACKED UP FLOW TO OUR EAST...AND HAVE TAKEN THAT INTO ACCOUNT FROM A SMART BLEND OF GUIDANCE POPS...SLOWING THEM SOMEWHAT. ONCE AGAIN TEMPERATURES ON FRIDAY DEPEND HEAVILY ON WHETHER OR NOT CLOUDS AND PRECIP ARE AS PROLIFIC AS MOST GUIDANCE IS INDICATING NOW. GRADUALLY BUILDING HEIGHTS SHOULD FOLLOW THAT SYSTEM DEPARTURE SOMETIME LATE FRIDAY/THIS WEEKEND. MTF && .CLIMATE... 625 AM CDT THE FOLLOWING ARE THE LAST APRIL DATES AND AMOUNTS OF ACCUMULATING SNOWFALL: CHICAGO: APRIL 18 2011 (0.6 IN.) ROCKFORD: APRIL 5 2009 (0.2 IN.) THE FOLLOWING ARE RECORD LOWS FOR THE MORNING OF APRIL 15TH. THE CHICAGO ONE IS THE MOST LIKELY IN JEOPARDY. CHICAGO: 25 (1943) ROCKFORD: 16 (1928) MTF && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 09Z... * GUSTY SOUTHERLY WINDS TURNING SHARPLY TO THE NORTH OVERNIGHT WITH CIGS DROPPING NEAR OR TO IFR. * OCCASIONAL CHANCES FOR RAIN SHOWERS OVERNIGHT...AND CHANCE FOR SNOW ACCUMULATIONS DURING THE DAY MONDAY. BMD //DISCUSSION...UPDATED 06Z... LOW PRESSURE LIES NEAR MLI TONIGHT WITH A FRONTAL BOUNDARY EXTENDING ACROSS FAR NORTHERN ILLINOIS. STRONG SOUTHERLY WINDS ARE OCCURRING ON THE SOUTH SIDE OF THE FRONT AT THE CHICAGO TERMINALS...BUT AS THE LOW MOVES EAST OVERNIGHT WINDS WILL TURN SHARPLY TO THE NORTH BEHIND THE DEPARTING LOW. CIGS WILL DROP TO AROUND 007-010 BEHIND THE FRONT AND WINDS WILL BECOME QUITE GUSTY...TO AROUND 30 KT OR SO AT TIMES THROUGH THE MORNING...THEN TAPERING GRADUALLY IN THE AFTERNOON AND EVENING. ALSO MONDAY AFTERNOON...AN UPPER LEVEL DISTURBANCE MOVING OVER THE AREA WILL ALLOW PRECIPITATION TO ONCE AGAIN OVERSPREAD THE TERMINALS. WITH MUCH COLDER AIR IN PLACE TOMORROW...IT DOES APPEAR MUCH OF THE PRECIP WILL FALL AS SNOW AND CANNOT RULE OUT ACCUMULATIONS TO AROUND AN INCH. SURFACE TEMPERATURES MAY INITIALLY MAKE IT DIFFICULT FOR SNOW TO ACCUMULATE...BUT AS SURFACE TEMPS FALL TO NEAR FREEZING IN THE EVENING CHANCES BECOME A BIT BETTER. BMD //ORD AND MDW CONFIDENCE...UPDATED 09Z... * MEDIUM-HIGH CONFIDENCE IN WIND DIRECTION/SPEED. * LOW-MEDIUM CONFIDENCE IN CIGS OVERNIGHT. * MEDIUM CONFIDENCE IN SNOW TIMING. BMD //OUTLOOK FOR ORD/MDW FOR 12Z TUESDAY-12Z SUNDAY...UPDATED 00Z... TUESDAY THROUGH THURSDAY...PREDOMINANTLY VFR. FRIDAY...CHANCE OF SHRA. SATURDAY...VFR PROBABLE. IZZI && .MARINE... 240 AM CDT LOW PRESSURE IS MOVING ACROSS FAR SOUTHERN LAKE MICHIGAN EARLY THIS MORNING WITH GALE FORCE NORTHERLY WINDS OVERSPREADING THE LAKE BEHIND THE LOW AS IT BEGINS TO DEPART EAST. GALES ARE EXPECTED TO PERSIST THROUGH THE AFTERNOON...THEN SHOULD VERY GRADUALLY DIMINISH TO AROUND 30 KT THIS EVENING AND TONIGHT. FOG THAT WAS IN PLACE NEAR THE FRONTAL BOUNDARY ACROSS FAR SOUTHERN LAKE MICHIGAN SHOULD DIMINISH AS THE NORTHERLY WINDS OVERSPREAD THE LAKE. RIDGING WILL TRANSLATE ACROSS LAKE MICHIGAN LATE IN THE DAY TUESDAY ALLOWING WINDS TO BRIEFLY SUBSIDE...BUT SOUTH/SOUTHEAST WINDS PICK UP AGAIN ON WEDNESDAY AS ANOTHER LOW DEVELOPS OVER THE CENTRAL PLAINS. BMD && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565- LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868- LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 3 PM MONDAY. GALE WARNING...NEARSHORE WATERS UNTIL 4 PM MONDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
406 AM CDT MON APR 14 2014 .DISCUSSION... 330 AM CDT THE INFAMOUS WINTER 2013-2014 BEGAN IN OCTOBER WITH SNOW AND TODAY IT WANTS TO MAKE SURE IT INCLUDES APRIL TO ENCOMPASS SEVEN MONTHS. THIS UNFRIENDLY VERY LATE VISIT FROM WINTER WAS THE PRIMARY FORECAST CHALLENGE...ALONG WITH TEMPERATURES THROUGHOUT THE WEEK AS WE WILL BE WELL BELOW NORMAL TO START THIS WEEK...POTENTIALLY TO RECORD LEVELS TONIGHT. THIS MORNING... THE 995MB SURFACE LOW IS PASSING OVER THE NORTH METRO OF CHICAGO EARLY THIS MORNING AND 30 MILES EITHER SIDE OF ITS PATH SEPARATES 60S AND CONVECTIVE RAIN SHOWERS AND 30S AND DEFORMATION SNOW. THE DEEPENING AND CLASSIC LOOKING UPPER WAVE WITH THIS IS ADVANCING NORTHEAST FROM SOUTHWEST WI AND ITS DEFORMATION AND WRAPAROUND MOISTURE WILL ONLY GRAZE THE AREA THIS MORNING. WHILE A MIX WITH WET SNOW IS PROBABLE OVER PARTS OF NORTH CENTRAL IL...THE FORCING FOR MODEST SNOW RATES IS LIKELY TO REMAIN TO THE NORTH IN THE A.M. HOURS SO NOT EXPECTING ANY ACCUMULATIONS PRIOR TO NOON. WINDS ON THE BACKSIDE OF THE LOW THIS MORNING LOOK TO GUST TO AROUND 40 MPH AT TIMES...WHICH BESIDES ADDING QUITE A CHILL TO THE AIR...MAY REDUCE VISIBILITY UP BY ROCKFORD IF SNOW CAN MATERIALIZE THIS MORNING. OTHERWISE THOUGH...IMPACTS LOOK MINOR DURING THIS PERIOD. THIS AFTERNOON AND TONIGHT... A SECOND WELL-DEFINED UPPER CIRCULATION IS ADVANCING EASTWARD INTO THE CENTRAL PLAINS EARLY THIS MORNING. THIS IS BASICALLY ROUNDING THE BASE OF WHAT REALLY IS A MASSIVE LONGWAVE TROUGH ACROSS CENTRAL NORTH AMERICA...WITH AN IMPRESSIVE JANUARY-LIKE -40C OBSERVED AT 500MB LAST NIGHT ALL THE WAY SOUTH TO CYQD IN SOUTHERN MANITOBA. GIVEN THE UPPER FLOW...PV ANOMALY EVOLUTION...AND MID-LEVEL BAROCLINICITY...THIS WAVE IS FORECAST TO TURN MORE NORTHEAST THIS AFTERNOON AND ADVANCE INTO CENTRAL AND NORTHERN IL/IN DURING THE MID-AFTERNOON INTO MID-EVE. THIS WILL BRING WITH IT FOCUSED OMEGA AND FRONTOGENETIC SUPPORTED UPWARD MOTION DURING THAT PERIOD AND WOULD EXPECT TO SEE MODERATE PRECIPITATION DEVELOPING FROM SOUTHWEST TO NORTHEAST ACROSS THE HEART OF THE FORECAST AREA...LIKELY REACHING THE CHICAGO AREA DURING THE 3-6 PM TIME. SO HAVE BUMPED UP POPS CONSIDERABLY. IN ADDITION...THE MID-LEVEL TEMPERATURES WILL CONTINUE TO COOL WITH THE FEATURE AND THE LOWER LEVELS THROUGH DIABATIC EFFECTS. ITS QUITE RARE TO SEE SNOW HERE DURING APRIL /ESPECIALLY MID-APRIL/ AFTERNOONS...BUT DO SEE PRECIPITATION STRUGGLING TO STAY AS RAIN GIVEN RAP AND NAM FORECAST THERMAL PROFILES AND JUST THE DEGREE OF FORCING. SO A QUICK TRANSITION TO A WET SNOW FROM NORTH TO SOUTH ACROSS THE CHICAGO METRO AREA IS FAVORED DURING THE RUSH HOUR...AND PROBABLY THE FIRST HALF AT THAT. SUPPRESSION ALOFT FOLLOWS BEHIND THE UPPER WAVE LATE THIS EVE INTO OVERNIGHT AND WILL END THE SNOW /FOR GOOD FINALLY?/. ANY INITIAL SNOW WILL STRUGGLE TO STICK WITH 4-INCH SOIL TEMPS AROUND 50 DEGREES AND THE WET GROUND IN PLACES...BUT THE FORCING LIKELY IS TO WIN OUT FOR A LIGHT COATING ESPECIALLY ON GRASSY SURFACES. THIS IS PRESENTLY MOST FAVORED ALONG AND SOUTH OF A MENDOTA TO CHICAGO LINE...AS THAT IS THE AREA THAT LOOKS TO HAVE THE BEST FORCING AS THE TEMPERATURES COOL LATE IN THE DAY AND THIS EVE. THERE IS UNCERTAINTY WITH THIS PLACEMENT THOUGH...AS SOME MESOSCALE PARAMETERS ARE AT PLAY. ACCUMULATION AROUND AN INCH TO A LITTLE OVER MAY OCCUR IN THE AREA THAT DOES END UP SEEING THE BETTER FORCING THANKS TO DECENT SNOWFALL RATES AT TIMES. TEMPERATURES WILL HOLD FLAT-LINE AND EVEN DROP DURING THE AFTERNOON AS PRECIPITATION EVOLVES INTO THE REGION. COLD AIR ADVECTION CONTINUES TONIGHT WITH 850MB TEMPS DROPPING TO THE -10C ARENA. THIS WILL SUPPORT CHICAGO CLOSING IN ON A RECORD LOW FOR TONIGHT /CALENDAR DAY OF APRIL 15/. SEE CLIMATE SECTION BELOW FOR MORE. TUESDAY THROUGH THURSDAY... NOT TOO MANY CHANGES MADE TO THIS PERIOD WHICH LOOKS MAINLY QUIET. A CHILLY TUESDAY IS EXPECTED WITH THE LOW STARTING POINT AND THE 850-925MB THERMAL TROUGH OVER US IN THE MORNING. A LAKE BREEZE DEVELOPING THAT AFTERNOON WILL NOT HELP MATTERS EITHER. UPPER 30S TO MID 40S ARE EXPECTED FROM NEAR THE LAKE TO THE REST OF THE FORECAST AREA ON TUESDAY AFTERNOON. UNCERTAINTY EXISTS ON CLOUD COVER FOR MUCH OF THIS TIME RANGE AND THAT WILL OF COURSE IMPACT TEMPERATURES GREATLY. THIS INCLUDES HIGH CLOUDS TUESDAY NIGHT WHICH COULD PREVENT ANOTHER CHILLY NIGHT IN THE 20S...AND HAVE INCHED UP FORECAST VALUES SOME FAVORING A LITTLE MORE CLOUD COVER AT THIS TIME. IN ADDITION...THURSDAY INTO THURSDAY NIGHT LOOKS TO HAVE SOUTHERLY FLOW AND THERE ARE INDICATIONS OF LOW CLOUDS MOVING NORTH DURING THAT TIME FRAME. WILL NEED TO WAIT TO THAT PERIOD GETS CLOSER TO GET TOO FANCY WITH TEMPERATURES BUT HAVE GONE WITH A BLEND OF GUIDANCE INCLUDING THE PREVIOUS FORECAST AT THIS TIME FOR TEMPS DURING THURSDAY. FRIDAY AND BEYOND... GIVEN A MASSIVE UPPER RIDGE OVER THE WESTERN TO NORTHERN ATLANTIC...ANY SHARP ADVANCEMENT OF AN UPPER RIDGE FROM THE WEST INTO OUR AREA LOOKS TO BE HALTED/SLOWED. WE WILL BUILD HEIGHTS GRADUALLY THURSDAY BUT MODEL GUIDANCE IS IN DECENT AGREEMENT WITH ADVANCING A PACIFIC SYSTEM INTO THE REGION BY FRIDAY AND PRODUCING LIKELY RAIN IN THE GENERAL REGION. THIS COULD SLOW GIVEN THE BACKED UP FLOW TO OUR EAST...AND HAVE TAKEN THAT INTO ACCOUNT FROM A SMART BLEND OF GUIDANCE POPS...SLOWING THEM SOMEWHAT. ONCE AGAIN TEMPERATURES ON FRIDAY DEPEND HEAVILY ON WHETHER OR NOT CLOUDS AND PRECIP ARE AS PROLIFIC AS MOST GUIDANCE IS INDICATING NOW. GRADUALLY BUILDING HEIGHTS SHOULD FOLLOW THAT SYSTEM DEPARTURE SOMETIME LATE FRIDAY/THIS WEEKEND. MTF && .CLIMATE... 400 AM CDT THE FOLLOWING ARE RECORD LOWS FOR THE MORNING OF APRIL 15TH. THE CHICAGO ONE IS MOST LIKELY IN JEOPARDY. CHICAGO: 25 (1943) ROCKFORD: 16 (1928) MTF && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 09Z... * GUSTY SOUTHERLY WINDS TURNING SHARPLY TO THE NORTH OVERNIGHT WITH CIGS DROPPING NEAR OR TO IFR. * OCCASIONAL CHANCES FOR RAIN SHOWERS OVERNIGHT...AND CHANCE FOR SNOW ACCUMULATIONS DURING THE DAY MONDAY. BMD //DISCUSSION...UPDATED 06Z... LOW PRESSURE LIES NEAR MLI TONIGHT WITH A FRONTAL BOUNDARY EXTENDING ACROSS FAR NORTHERN ILLINOIS. STRONG SOUTHERLY WINDS ARE OCCURRING ON THE SOUTH SIDE OF THE FRONT AT THE CHICAGO TERMINALS...BUT AS THE LOW MOVES EAST OVERNIGHT WINDS WILL TURN SHARPLY TO THE NORTH BEHIND THE DEPARTING LOW. CIGS WILL DROP TO AROUND 007-010 BEHIND THE FRONT AND WINDS WILL BECOME QUITE GUSTY...TO AROUND 30 KT OR SO AT TIMES THROUGH THE MORNING...THEN TAPERING GRADUALLY IN THE AFTERNOON AND EVENING. ALSO MONDAY AFTERNOON...AN UPPER LEVEL DISTURBANCE MOVING OVER THE AREA WILL ALLOW PRECIPITATION TO ONCE AGAIN OVERSPREAD THE TERMINALS. WITH MUCH COLDER AIR IN PLACE TOMORROW...IT DOES APPEAR MUCH OF THE PRECIP WILL FALL AS SNOW AND CANNOT RULE OUT ACCUMULATIONS TO AROUND AN INCH. SURFACE TEMPERATURES MAY INITIALLY MAKE IT DIFFICULT FOR SNOW TO ACCUMULATE...BUT AS SURFACE TEMPS FALL TO NEAR FREEZING IN THE EVENING CHANCES BECOME A BIT BETTER. BMD //ORD AND MDW CONFIDENCE...UPDATED 09Z... * MEDIUM-HIGH CONFIDENCE IN WIND DIRECTION/SPEED. * LOW-MEDIUM CONFIDENCE IN CIGS OVERNIGHT. * MEDIUM CONFIDENCE IN SNOW TIMING. BMD //OUTLOOK FOR ORD/MDW FOR 12Z TUESDAY-12Z SUNDAY...UPDATED 00Z... TUESDAY THROUGH THURSDAY...PREDOMINANTLY VFR. FRIDAY...CHANCE OF SHRA. SATURDAY...VFR PROBABLE. IZZI && .MARINE... 240 AM CDT LOW PRESSURE IS MOVING ACROSS FAR SOUTHERN LAKE MICHIGAN EARLY THIS MORNING WITH GALE FORCE NORTHERLY WINDS OVERSPREADING THE LAKE BEHIND THE LOW AS IT BEGINS TO DEPART EAST. GALES ARE EXPECTED TO PERSIST THROUGH THE AFTERNOON...THEN SHOULD VERY GRADUALLY DIMINISH TO AROUND 30 KT THIS EVENING AND TONIGHT. FOG THAT WAS IN PLACE NEAR THE FRONTAL BOUNDARY ACROSS FAR SOUTHERN LAKE MICHIGAN SHOULD DIMINISH AS THE NORTHERLY WINDS OVERSPREAD THE LAKE. RIDGING WILL TRANSLATE ACROSS LAKE MICHIGAN LATE IN THE DAY TUESDAY ALLOWING WINDS TO BRIEFLY SUBSIDE...BUT SOUTH/SOUTHEAST WINDS PICK UP AGAIN ON WEDNESDAY AS ANOTHER LOW DEVELOPS OVER THE CENTRAL PLAINS. BMD && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565- LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868- LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 3 PM MONDAY. GALE WARNING...NEARSHORE WATERS UNTIL 4 PM MONDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
330 AM CDT MON APR 14 2014 .DISCUSSION... 330 AM CDT THE INFAMOUS WINTER 2013-2014 BEGAN IN OCTOBER WITH SNOW AND TODAY IT WANTS TO MAKE SURE IT INCLUDES APRIL TO ENCOMPASS SEVEN MONTHS. THIS UNFRIENDLY VERY LATE VISIT FROM WINTER WAS THE PRIMARY FORECAST CHALLENGE...ALONG WITH TEMPERATURES THROUGHOUT THE WEEK AS WE WILL BE WELL BELOW NORMAL TO START THIS WEEK...POTENTIALLY TO RECORD LEVELS TONIGHT. THIS MORNING... THE 995MB SURFACE LOW IS PASSING OVER THE NORTH METRO OF CHICAGO EARLY THIS MORNING AND 30 MILES EITHER SIDE OF ITS PATH SEPARATES 60S AND CONVECTIVE RAIN SHOWERS AND 30S AND DEFORMATION SNOW. THE DEEPENING AND CLASSIC LOOKING UPPER WAVE WITH THIS IS ADVANCING NORTHEAST FROM SOUTHWEST WI AND ITS DEFORMATION AND WRAPAROUND MOISTURE WILL ONLY GRAZE THE AREA THIS MORNING. WHILE A MIX WITH WET SNOW IS PROBABLE OVER PARTS OF NORTH CENTRAL IL...THE FORCING FOR MODEST SNOW RATES IS LIKELY TO REMAIN TO THE NORTH IN THE A.M. HOURS SO NOT EXPECTING ANY ACCUMULATIONS PRIOR TO NOON. WINDS ON THE BACKSIDE OF THE LOW THIS MORNING LOOK TO GUST TO AROUND 40 MPH AT TIMES...WHICH BESIDES ADDING QUITE A CHILL TO THE AIR...MAY REDUCE VISIBILITY UP BY ROCKFORD IF SNOW CAN MATERIALIZE THIS MORNING. OTHERWISE THOUGH...IMPACTS LOOK MINOR DURING THIS PERIOD. THIS AFTERNOON AND TONIGHT... A SECOND WELL-DEFINED UPPER CIRCULATION IS ADVANCING EASTWARD INTO THE CENTRAL PLAINS EARLY THIS MORNING. THIS IS BASICALLY ROUNDING THE BASE OF WHAT REALLY IS A MASSIVE LONGWAVE TROUGH ACROSS CENTRAL NORTH AMERICA...WITH AN IMPRESSIVE JANUARY-LIKE -40C OBSERVED AT 500MB LAST NIGHT ALL THE WAY SOUTH TO CYQD IN SOUTHERN MANITOBA. GIVEN THE UPPER FLOW...PV ANOMALY EVOLUTION...AND MID-LEVEL BAROCLINICITY...THIS WAVE IS FORECAST TO TURN MORE NORTHEAST THIS AFTERNOON AND ADVANCE INTO CENTRAL AND NORTHERN IL/IN DURING THE MID-AFTERNOON INTO MID-EVE. THIS WILL BRING WITH IT FOCUSED OMEGA AND FRONTOGENETIC SUPPORTED UPWARD MOTION DURING THAT PERIOD AND WOULD EXPECT TO SEE MODERATE PRECIPITATION DEVELOPING FROM SOUTHWEST TO NORTHEAST ACROSS THE HEART OF THE FORECAST AREA...LIKELY REACHING THE CHICAGO AREA DURING THE 3-6 PM TIME. SO HAVE BUMPED UP POPS CONSIDERABLY. IN ADDITION...THE MID-LEVEL TEMPERATURES WILL CONTINUE TO COOL WITH THE FEATURE AND THE LOWER LEVELS THROUGH DIABATIC EFFECTS. ITS QUITE RARE TO SEE SNOW HERE DURING APRIL /ESPECIALLY MID-APRIL/ AFTERNOONS...BUT DO SEE PRECIPITATION STRUGGLING TO STAY AS RAIN GIVEN RAP AND NAM FORECAST THERMAL PROFILES AND JUST THE DEGREE OF FORCING. SO A QUICK TRANSITION TO A WET SNOW FROM NORTH TO SOUTH ACROSS THE CHICAGO METRO AREA IS FAVORED DURING THE RUSH HOUR...AND PROBABLY THE FIRST HALF AT THAT. SUPPRESSION ALOFT FOLLOWS BEHIND THE UPPER WAVE LATE THIS EVE INTO OVERNIGHT AND WILL END THE SNOW /FOR GOOD FINALLY?/. ANY INITIAL SNOW WILL STRUGGLE TO STICK WITH 4-INCH SOIL TEMPS AROUND 50 DEGREES AND THE WET GROUND IN PLACES...BUT THE FORCING LIKELY IS TO WIN OUT FOR A LIGHT COATING ESPECIALLY ON GRASSY SURFACES. THIS IS PRESENTLY MOST FAVORED ALONG AND SOUTH OF A MENDOTA TO CHICAGO LINE...AS THAT IS THE AREA THAT LOOKS TO HAVE THE BEST FORCING AS THE TEMPERATURES COOL LATE IN THE DAY AND THIS EVE. THERE IS UNCERTAINTY WITH THIS PLACEMENT THOUGH...AS SOME MESOSCALE PARAMETERS ARE AT PLAY. ACCUMULATION AROUND AN INCH TO A LITTLE OVER MAY OCCUR IN THE AREA THAT DOES END UP SEEING THE BETTER FORCING THANKS TO DECENT SNOWFALL RATES AT TIMES. TEMPERATURES WILL HOLD FLAT-LINE AND EVEN DROP DURING THE AFTERNOON AS PRECIPITATION EVOLVES INTO THE REGION. COLD AIR ADVECTION CONTINUES TONIGHT WITH 850MB TEMPS DROPPING TO THE -10C ARENA. THIS WILL SUPPORT CHICAGO CLOSING IN ON A RECORD LOW FOR TONIGHT /CALENDAR DAY OF APRIL 15/. SEE CLIMATE SECTION BELOW FOR MORE. TUESDAY THROUGH THURSDAY... NOT TOO MANY CHANGES MADE TO THIS PERIOD WHICH LOOKS MAINLY QUIET. A CHILLY TUESDAY IS EXPECTED WITH THE LOW STARTING POINT AND THE 850-925MB THERMAL TROUGH OVER US IN THE MORNING. A LAKE BREEZE DEVELOPING THAT AFTERNOON WILL NOT HELP MATTERS EITHER. UPPER 30S TO MID 40S ARE EXPECTED FROM NEAR THE LAKE TO THE REST OF THE FORECAST AREA ON TUESDAY AFTERNOON. UNCERTAINTY EXISTS ON CLOUD COVER FOR MUCH OF THIS TIME RANGE AND THAT WILL OF COURSE IMPACT TEMPERATURES GREATLY. THIS INCLUDES HIGH CLOUDS TUESDAY NIGHT WHICH COULD PREVENT ANOTHER CHILLY NIGHT IN THE 20S...AND HAVE INCHED UP FORECAST VALUES SOME FAVORING A LITTLE MORE CLOUD COVER AT THIS TIME. IN ADDITION...THURSDAY INTO THURSDAY NIGHT LOOKS TO HAVE SOUTHERLY FLOW AND THERE ARE INDICATIONS OF LOW CLOUDS MOVING NORTH DURING THAT TIME FRAME. WILL NEED TO WAIT TO THAT PERIOD GETS CLOSER TO GET TOO FANCY WITH TEMPERATURES BUT HAVE GONE WITH A BLEND OF GUIDANCE INCLUDING THE PREVIOUS FORECAST AT THIS TIME FOR TEMPS DURING THURSDAY. FRIDAY AND BEYOND... GIVEN A MASSIVE UPPER RIDGE OVER THE WESTERN TO NORTHERN ATLANTIC...ANY SHARP ADVANCEMENT OF AN UPPER RIDGE FROM THE WEST INTO OUR AREA LOOKS TO BE HALTED/SLOWED. WE WILL BUILD HEIGHTS GRADUALLY THURSDAY BUT MODEL GUIDANCE IS IN DECENT AGREEMENT WITH ADVANCING A PACIFIC SYSTEM INTO THE REGION BY FRIDAY AND PRODUCING LIKELY RAIN IN THE GENERAL REGION. THIS COULD SLOW SOME GIVEN THE BACKED UP FLOW TO OUR EAST...AND HAVE TAKEN THAT INTO ACCOUNT FROM A SMART BLEND OF GUIDANCE POPS...SLOWING THEM SOMEWHAT. ONCE AGAIN TEMPERATURES ON FRIDAY DEPEND HEAVILY ON WHETHER OR NOT CLOUDS AND PRECIP ARE AS PROLIFIC AS MOST GUIDANCE IS INDICATING NOW. GRADUALLY BUILDING HEIGHTS SHOULD FOLLOW THAT SYSTEM DEPARTURE SOMETIME LATE FRIDAY/THIS WEEKEND. MTF && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 06Z... * GUSTY SOUTHERLY WINDS TURNING SHARPLY TO THE NORTH OVERNIGHT WITH CIGS DROPPING NEAR OR TO IFR. * OCCASIONAL CHANCES FOR RAIN SHOWERS OVERNIGHT...AND CHANCE FOR SNOW ACCUMULATIONS DURING THE DAY MONDAY. BMD //DISCUSSION...UPDATED 06Z... LOW PRESSURE LIES NEAR MLI TONIGHT WITH A FRONTAL BOUNDARY EXTENDING ACROSS FAR NORTHERN ILLINOIS. STRONG SOUTHERLY WINDS ARE OCCURRING ON THE SOUTH SIDE OF THE FRONT AT THE CHICAGO TERMINALS...BUT AS THE LOW MOVES EAST OVERNIGHT WINDS WILL TURN SHARPLY TO THE NORTH BEHIND THE DEPARTING LOW. CIGS WILL DROP TO AROUND 007-010 BEHIND THE FRONT AND WINDS WILL BECOME QUITE GUSTY...TO AROUND 30 KT OR SO AT TIMES THROUGH THE MORNING...THEN TAPERING GRADUALLY IN THE AFTERNOON AND EVENING. ALSO MONDAY AFTERNOON...AN UPPER LEVEL DISTURBANCE MOVING OVER THE AREA WILL ALLOW PRECIPITATION TO ONCE AGAIN OVERSPREAD THE TERMINALS. WITH MUCH COLDER AIR IN PLACE TOMORROW...IT DOES APPEAR MUCH OF THE PRECIP WILL FALL AS SNOW AND CANNOT RULE OUT ACCUMULATIONS TO AROUND AN INCH. SURFACE TEMPERATURES MAY INITIALLY MAKE IT DIFFICULT FOR SNOW TO ACCUMULATE...BUT AS SURFACE TEMPS FALL TO NEAR FREEZING IN THE EVENING CHANCES BECOME A BIT BETTER. BMD //ORD AND MDW CONFIDENCE...UPDATED 06Z... * MEDIUM-HIGH CONFIDENCE IN WIND DIRECTION/SPEED. * LOW-MEDIUM CONFIDENCE IN CIGS OVERNIGHT. * MEDIUM CONFIDENCE IN SNOW TIMING. BMD //OUTLOOK FOR ORD/MDW FOR 12Z TUESDAY-12Z SUNDAY...UPDATED 00Z... TUESDAY THROUGH THURSDAY...PREDOMINANTLY VFR. FRIDAY...CHANCE OF SHRA. SATURDAY...VFR PROBABLE. IZZI && .MARINE... 240 AM CDT LOW PRESSURE IS MOVING ACROSS FAR SOUTHERN LAKE MICHIGAN EARLY THIS MORNING WITH GALE FORCE NORTHERLY WINDS OVERSPREADING THE LAKE BEHIND THE LOW AS IT BEGINS TO DEPART EAST. GALES ARE EXPECTED TO PERSIST THROUGH THE AFTERNOON...THEN SHOULD VERY GRADUALLY DIMINISH TO AROUND 30 KT THIS EVENING AND TONIGHT. FOG THAT WAS IN PLACE NEAR THE FRONTAL BOUNDARY ACROSS FAR SOUTHERN LAKE MICHIGAN SHOULD DIMINISH AS THE NORTHERLY WINDS OVERSPREAD THE LAKE. RIDGING WILL TRANSLATE ACROSS LAKE MICHIGAN LATE IN THE DAY TUESDAY ALLOWING WINDS TO BRIEFLY SUBSIDE...BUT SOUTH/SOUTHEAST WINDS PICK UP AGAIN ON WEDNESDAY AS ANOTHER LOW DEVELOPS OVER THE CENTRAL PLAINS. BMD && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...SMALL CRAFT ADVISORY...NEARSHORE WILMETTE HARBOR TO MICHIGAN CITY IN UNTIL 4 AM MONDAY. GALE WARNING...NEARSHORE WATERS UNTIL 4 PM MONDAY. DENSE FOG ADVISORY...NEARSHORE WINTHROP TO WILMETTE HARBORS UNTIL 4 AM MONDAY. GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565- LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868- LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 3 PM MONDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
120 AM EDT MON APR 14 2014 .SYNOPSIS... ISSUED AT 830 PM EDT SUN APR 13 2014 SHOWERS AND SCATTERED THUNDERSTORMS WILL BECOME MORE PREVALENT TONIGHT AS AN UPPER LEVEL DISTURBANCE APPROACHES THE REGION FROM THE PLAINS. A COLD FRONT ASSOCIATED WITH THIS SYSTEM WILL TRACK ACROSS THE REGION ON MONDAY...BRINGING COLDER AND BLUSTERY CONDITIONS. RAIN WILL TAPER IN COVERAGE DURING THE DAY MONDAY...BUT ANOTHER DISTURBANCE WILL BRING A CHANCE OF LIGHT SNOW ACCUMULATIONS FOR MONDAY NIGHT. && .UPDATE... ISSUED AT 830 PM EDT SUN APR 13 2014 AN AREA OF SHOWERS AND ISOLATED THUNDERSTORMS ASSOCIATED WITH SMALL SCALE UPPER VORT MAX SHOULD EXIT FAR NORTHWEST PORTIONS OF THE AREA OVER THE NEXT OVER. LULL IN PRECIP WILL BE RELATIVELY SHORT LIVED AS STRONGER UPPER LEVEL SHORT WAVE WILL CONTINUE TO TRACK INTO NORTHWEST INDIANA OVERNIGHT. A LARGE AREA OF ENHANCED LOW LEVEL MOISTURE TRANSPORT NOTED PER LATEST RAP ANALYSIS ACROSS THE MID MS RIVER VALLEY WILL SHIFT EASTWARD AND EXTEND FROM THE LOWER OHIO VALLEY INTO THE SOUTHERN GREAT LAKES BY 09Z. A LARGE AREA OF RAIN/EMBEDDED THUNDERSTORMS COINCIDING WITH THIS STRONGER LOW LEVEL MOISTURE TRANSPORT ACROSS SOUTHEAST MISSOURI WILL CONTINUE TO EXPAND NORTHEASTWARD OVERNIGHT...BRINGING WIDESPREAD RAIN/EMBEDDED THUNDER TO MOST OF THE FORECAST AREA THROUGH EARLY MONDAY MORNING. NORTHWARD ADVECTION OF 1.25-1.40 INCH PWAT AXIS INTO THE AREA OVERNIGHT AND STRENGTHENING LOW LEVEL FRONTAL CIRCULATION SHOULD PROMOTE SOME HEALTHY RAINFALL AMOUNTS POSSIBLY APPROACHING AROUND AN INCH ACROSS WESTERN PORTIONS OF THE AREA WHICH COULD LEAD TO SOME MINOR FLOODING CONCERNS GIVEN RECENT WET PERIOD/MOIST SOILS. MAIN TWEAKS TO FORECAST THIS EVENING WERE TO SLIGHTLY INCREASE POPS OVERNIGHT IN ASSOCIATION WITH ABOVE MENTIONED TRENDS...ALONG WITH SLIGHT ADJUSTMENT TO HOURLY TEMP CURVE ACROSS THE NORTHWEST COOLER TEMPS RESIDE INITIALLY DUE TO EARLIER MARINE INFLUENCE. BEST CHANCE OF THUNDER APPEARS TO BE DURING THE OVERNIGHT HOURS...WHERE SLIGHT ENHANCEMENT TO WEAK ELEVATED INSTABILITY IS EXPECTED IN ASSOCIATION WITH LOW LEVEL MOIST TONGUE. && .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 328 PM EDT SUN APR 13 2014 VIGOROUS LOW PRESSURE OVR KS THIS AFTN WILL LIFT QUICKLY NEWD INTO THE MI THUMB BY DAYBREAK TOMORROW AND PROPEL A STG CDFNT EWD ACRS THE AREA. SO FAR WARM SECTOR HAS BEEN A DUD WITH THIS SYS OWING TO POOR MSTR RTN UNDERNEATH STEEP EML AND SEE LTL EVIDENCE THAT WILL CHANGE INTO EARLY EVE. BETTER PROSPECTS FOR RAINFALL XPCD LT TONIGHT AHD AND ALG SFC FNTL BNDRY. HWVR WKNG CAP WITHIN ZONE OF FVRBL THETA-E AND SUSTAINED LL WAA STILL WARRANTS HOLDING ONTO SOME POPS NW THIRD THROUGH EVENING. OTRWS STG POST FNTL CAA WEDGE FOLLOWS MON AM W/CRASHING SFC TEMPS. LINGERING POST FNTL SHRA XPCD IN THE MORNING FOLLOWED BY LARGELY DRY CONDS IN THE AFTN ASSOCD/W MID LVL DRY SLOT OF EXITING SYS ALOFT. && .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 328 PM EDT SUN APR 13 2014 FOCUS OF FORECAST WILL BE ON ARRIVAL OF UNSEASONABLY COLD AIR AND ACCUMULATING SNOWFALL AT THE START OF THE PERIOD. COLD FRONT SHOULD BE LONG GONE BY MONDAY EVENING WITH THE REGION IN A VERY BRIEF LULL IN PRECIP TO START THINGS OUT. THIS WILL QUICKLY CHANGE AS A DISTURBANCE MOVES ALONG THE FRONT AND BRINGS ANOTHER QUICK SHOT OF INCREASED MSTR AND LIFT. MODELS DO VARY ON EXACTLY HOW MUCH QPF BUT IN GENERAL PAINT THE NEED FOR LIKELY TO CAT POPS FOR MOST AREAS FOR A PERIOD...MAINLY IN THE 3Z TO 9Z TUES TIME FRAME. HAVE BROKE GRIDS INTO 3 HOUR BLOCKS TO TRY TO ADD SOME DETAIL IN TERMS OF TIMING. GIVEN RATHER PRONOUNCED/FAST ARRIVING PUNCH OF COLD AIR...MIX POTENTIAL FOR PRECIP LOOKING MORE LIMITED WITH 1000-850 MB THICKNESS AND SFC TEMPS ALL POINTING TOWARDS ALL SNOW. THE BIGGEST CHALLENGE LIE WITH HOW MUCH PRECIP FALLS AND POTENTIAL ACCUMULATIONS. IMPRESSIVE 850 MB DROP FOR MID APRIL WITH VALUES FROM -8 TO - 10 C DURING BEST PRECIP WINDOW. AT THIS TIME...THINK MANY AREAS WILL SEE SOME WET SNOWFLAKES TO START THINGS OFF IN THE EVENING...WITH THIS SNOW BEING LESS WET WITH TIME AS COLDER AIR SETTLES IN AND SNOW RATIOS INCREASE SOMEWHAT. IF WE WERE STILL ENTRENCHED IN THE GENERALLY COLD PATTERN...WE MIGHT BE LOOKING AT SEVERAL INCHES OF SNOW STICKING AROUND AND CAUSING A LOT OF PROBLEMS. HOWEVER...DESPITE THE COLD AIR ARRIVING...ROAD/GROUND TEMPS HAVE WARMED SUBSTANTIALLY GIVEN THE 70S OF THE PAST COUPLE OF DAYS. THIS WILL LIKELY ALLOW FOR MELTING OF A LOT OF THE SNOWFALL...ESPECIALLY ON ROADS. HOWEVER...IF SNOW CAN COME DOWN HARD ENOUGH IT MAY BE ABLE TO ACCUMULATE AND STICK AROUND BRIEFLY INTO PARTS OF TUESDAY AS HIGHS STRUGGLE THROUGH THE 30S TO NEAR 40. GRIDS REFLECT ACCUMULATIONS OF 1 TO 3 INCHES WITH HIGHEST AMOUNTS IN SE AREAS WHERE MSTR WILL LINGER LONGER. AGAIN...IT NEEDS TO BE STRESSED THAT MUCH OF THIS SNOW MAY NOT ACCUMULATE IN THE EVENING BUT OVERNIGHT...ROADS COULD BECOME SLIPPERY IN SOME AREAS AS OVERNIGHT LOWS PLUMMET THROUGH THE 20S. FORECAST WILL NEED FINE TUNING FURTHER OVER THE NEXT 12 TO 24 HOURS. ONCE THIS SYSTEM PASSES BY...DRIER WEATHER WILL SETTLE IN UNTIL THURS NGT BEFORE THE NEXT SYSTEM BEGINS TO APPROACH THE REGION WITH CHANCES FOR SHOWERS. TEMPS WILL CLIMB BACK INTO THE 50S AND POSSIBLY 60S. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 120 AM EDT MON APR 14 2014 LEAD SHORTWAVE AND ATTENDANT SFC WAVE WILL LIFT NORTHEAST THROUGH THE GREAT LAKES REGION THIS MORNING...FINALLY FORCING A STRONG FRONTAL BOUNDARY EAST THROUGH SBN AROUND 12/13Z AND FWA 15/16Z. SHOWERS/ISO THUNDER AND DETERIORATING FLIGHT CONDITIONS EXPECTED AHEAD AND ALONG THIS FRONT IN IMPRESSIVE MOISTURE CHANNEL/50-60 KT LLJ. PERIOD OF IFR CONDITIONS REMAIN POSSIBLE ALONG BOUNDARY...WITH IFR TO MID RANGE MVFR CIGS AND GUSTY NORTHWESTERLY WINDS ANTICIPATED IN STRONG POST FRONTAL CAA WEDGE LATE THIS MORNING/AFTERNOON. CANNOT RULE OUT A FEW SHOWERS THIS AFTERNOON AS MID LEVEL BAROCLINIC ZONE LINGERS OVER NORTHERN INDIANA IN ADVANCE OF A CONSOLIDATING/AMPLIFYING CENTRAL CONUS UPPER TROUGH. RENEWED MID LEVEL FGEN/DEFORMATION WITH THIS UPPER TROUGH SHOULD ALLOW ANOTHER ROUND OF MORE WIDESPREAD PCPN TO OVERSPREAD NORTHERN INDIANA THIS EVENING INTO THE OVERNIGHT. MODEL THERMAL PROFILES ACTUALLY FAVOR MAINLY SNOW IN SBN...WITH A RAIN/SNOW MIX CHANGING OVER TO ALL SNOW IN FWA LATE IN THE EVENING/EARLY OVERNIGHT. && .MARINE... ISSUED AT 328 PM EDT SUN APR 13 2014 AREAS OF FOG BEING INTRODUCED TO NEARSHORE WATERS WITH WEB CAMS SHOWING FOG OFFSHORE...MORE THAN LIKELY MORE IN THE 3 TO 5 NM RANGE. TRENDS WILL BE MONITORED FOR NEED FOR MARINE DENSE FOG ADVISORY BUT MAIN THREAT SHOULD REMAIN IN OPEN WATERS. WILL ALSO HOIST SMALL CRAFT ADVISORY STARTING LATER TONIGHT AND CONTINUING THROUGH AT LEAST MONDAY IF NOT INTO TUESDAY. POTENTIAL FOR A PERIOD OF GALE FORCE GUSTS BUT HAVE KEPT WORDING TONED DOWN FOR THE TIME BEING WITH A FEW GUSTS TO 35 KTS. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...SMALL CRAFT ADVISORY UNTIL 7 AM EDT THIS MORNING FOR LMZ043-046. GALE WARNING FROM 7 AM THIS MORNING TO 5 PM EDT THIS AFTERNOON FOR LMZ043-046. && $$ UPDATE...MARSILI SYNOPSIS...MARSILI SHORT TERM...T LONG TERM...FISHER AVIATION...STEINWEDEL MARINE...FISHER VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.NORTHERNIN.GOV WWW.TWITTER.COM/NWSIWX WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS GOODLAND KS
310 PM MDT MON APR 14 2014 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 1252 PM MDT MON APR 14 2014 EARLY AFTERNOON WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOW TROUGH EXTENDING FROM GREAT LAKES ACROSS THE CENTRAL/SOUTHERN PLAINS AND RIDGE BUILDING OVER WESTERN US. AT THE SURFACE HIGH PRESSURE IS IN PLACE ACROSS EASTERN COLORADO/WESTERN KS WITH N-NW GRADIENT OVER KS/NE SUPPORTING GUSTY WINDS OVER OUR CWA. SNOW PACK HAS RETREATED OVER MUCH OF OUR CWA...WHILE VIS SATELLITE INDICATES IT HOLDING ON OVER PARTS OF NE COLORADO AND ALONG KS/NE STATE LINE WHERE AROUND INCHES OF SNOW FELL MONDAY AND MONDAY NIGHT. ON THE BACK SIDE OF DEPARTING UPPER LEVEL TROUGH H3 JET STEAM IS MOVING ACROSS NORTHERN PLAINS. STEEP LOW/MID LEVEL LAPSE RATES HAVE DEVELOPED WITH SHALLOW COOL LAYER AND DAYTIME HEATING AND HAS LED TO CU FIELD DEVELOPING OVER THE SOUTHERN PART OF OUR CWA. AS NOSE OF JET MOVES ACROSS CENTRAL NEBRASKA THERE MAY BE ENOUGH FORCING ALONG WITH THIS WEAKLY UNSTABLE MID LAYER FOR A FEW SPRINKLES TO MOVE INTO THE NORTHEAST CORNER OF OUR CWA...OTHERWISE WE ARE ONLY LOOKING AT A PERIOD OF MID LEVEL CU OVER OUR CWA THIS AFTERNOON. IF THERE IS A BETTER SHOWER WE COULD SEE A FLURRY INSTEAD OF SPRINKLE THROUGH...BUT I DIDN`T SEE A REASON TO GET THAT CUTE CONSIDERING CONFIDENCE IS ALREADY LOW ON PRECIP REACHING THE GROUND IN OUR NE CWA. ANOTHER HARD FREEZE IS EXPECTED TONIGHT...THOUGH THERE WILL BE SOME MODERATION OF THE AIR MASS ALOFT AS HIGH PRESSURE SHIFTS EAST AND W-SW WINDS DEVELOP LATE TONIGHT. MONDAY...CONTINUE MODERATION OF THE AIR MASS IS EXPECTED WITH DAYTIME HIGHS REACHING SEASONAL VALUES IN THE 60S ACROSS THE CWA. SNOW PACK COULD STILL IMPACT LOCATIONS IN THE NORTH...HOWEVER WITH SW WINDS COMING FROM SNOW FREE LOCATIONS WE SHOULD SEE A QUICK MELTING OF SNOW. MAIN CONCERN FOR MONDAY WILL BE POTENTIAL FOR RED FLAG CONDITIONS WITH WINDY CONDITIONS DEVELOPING EARLY IN THE WEST AND GOOD MIXING SUPPORTING LOWER TD VALUES ACROSS THE SOUTH. MODEL OUTPUT GENERALLY SUPPORTS A DECREASING TREND IN THE WEST IN THE AFTERNOON AS GRADIENT SHIFTS EAST...SO THERE MAY ONLY BE A SMALL WINDOW FOR WIND/RH CROSSOVER. OF COURSE THERE IS ALSO THE QUESTION OF WHETHER FUELS WILL BE CURED AFTER RECENT PRECIP (ESPECIALLY OVER LOCATIONS WITH LINGERING SNOW PACK). WITH TOO MUCH UNCERTAINTY I DECIDED AGAINST ISSUANCE OF FIRE WEATHER WATCH AT THIS TIME. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 237 PM MDT MON APR 14 2014 MODEL SOLUTIONS REMAIN IN CLOSE AGREEMENT THROUGH THE END OF THE WORK WEEK AND THEN BEGIN TO DIVERGE THROUGH THE WEEKEND AS AN UPPER TROUGH MOVES ACROSS THE NORTHERN PLAINS IN THE NORTHERN BRANCH OF THE UPPER FLOW AND A SHORT WAVE TROUGH EMBEDDED IN THE SOUTHERLY BRANCH TRIES TO COME INTO PHASE WITH THE NORTHERLY BRANCH. THE GFS REMAINS THE MORE PROGRESSIVE SOLUTION WHILE THE ECMWF LAGS BEHIND NEARLY 24 HOURS. THIS IS PROVING TO BE TROUBLESOME WITH THE TIMING OF THE PRECIPITATION THAT IS POSSIBLE BETWEEN A LATE FRIDAY TO LATE SATURDAY TIME FRAME. HAVE GONE WITH SOME KIND OF BLENDED COMPROMISE SOLUTION FOR THE FRIDAY THROUGH SUNDAY TIME PERIOD WITH RAIN SHOWERS TRANSITIONING TO A FEW THUNDERSTORMS AND BACK TO RAIN SHOWERS ON SATURDAY AND SATURDAY NIGHT. EXPECT DRY AND WARMER CONDITIONS THROUGH THE REMAINDER OF THE WEEKEND INTO THE BEGINNING OF NEXT WEEK AS A LARGE RIDGE AMPLIFIES OVER THE WESTERN UNITED STATES AND MOVES EAST OVER THE ROCKIES AND HIGH PLAINS REGION. BACKTRACKING TO THE MID-WEEK SYSTEM... EXPECT RAIN TO DEVELOP EAST OF THE ROCKIES LATE WEDNESDAY AND TRANSITION TO SNOW AS IT SPREADS ACROSS THE FORECAST AREA WEDNESDAY NIGHT. EXPECT A TRANSITION BACK TO RAIN DURING THE DAY ON THURSDAY...BUT MAY END UP STAYING MORE SNOW THROUGH THURSDAY MORNING IF TEMPERATURES REMAIN COLDER AND WET BULB ZERO TEMPERATURES ARE COLDER AS THEY WERE WITH THE LAST SYSTEM THAT DEPOSITED SNOW ACROSS THE FORECAST AREA. EXPECT PRECIPITATION TO END FROM WEST TO EAST ACROSS THE FORECAST AREA LATE IN THE DAY ON THURSDAY. TEMPS WILL WARM BRIEFLY ON FRIDAY AND SATURDAY AHEAD OF THE NEXT SYSTEM. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1133 AM MDT MON APR 14 2014 LAYER OF CU 3000-5000KFT AGL HAS DEVELOPED NEAR GLD WITH WEAKLY UNSTABLE LAYER ASSOCIATED WITH DAYTIME HEATING...AND A SECOND AREA OF CU ASSOCIATED THE WEAK UPPER LEVEL DISTURBANCE WILL MOVE OUT OF NEBRASKA OVER KMCK. CONDITIONS ARE EXPECTED TO REMAIN VFR WITH THESE CLOUDS CLEARING AROUND 00Z WITH LOSS OF DAYTIME HEATING. NW WINDS GUSTING TO 25KT AT BOTH TERMINALS WILL DIMINISH AROUND SUNSET. WINDS SHOULD SHIFT TO THE WEST THEN SOUTHWEST WITH LEE TROUGH BEGINNING TO BUILD OVERNIGHT...THEN INCREASE FROM THE WEST TUESDAY MORNING. EXPECT GUSTS AT KGLD AROUND SUNRISE TUESDAY TO 25KT...POSSIBLY HIGHER. AT KMCK...WINDS WILL LIKELY INCREASE OUTSIDE THE CURRENT TAF PERIOD. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...DR LONG TERM...LOCKHART AVIATION...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1254 PM MDT MON APR 14 2014 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 1252 PM MDT MON APR 14 2014 EARLY AFTERNOON WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOW TROUGH EXTENDING FROM GREAT LAKES ACROSS THE CENTRAL/SOUTHERN PLAINS AND RIDGE BUILDING OVER WESTERN US. AT THE SURFACE HIGH PRESSURE IS IN PLACE ACROSS EASTERN COLORADO/WESTERN KS WITH N-NW GRADIENT OVER KS/NE SUPPORTING GUSTY WINDS OVER OUR CWA. SNOW PACK HAS RETREATED OVER MUCH OF OUR CWA...WHILE VIS SATELLITE INDICATES IT HOLDING ON OVER PARTS OF NE COLORADO AND ALONG KS/NE STATE LINE WHERE AROUND INCHES OF SNOW FELL MONDAY AND MONDAY NIGHT. ON THE BACK SIDE OF DEPARTING UPPER LEVEL TROUGH H3 JET STEAM IS MOVING ACROSS NORTHERN PLAINS. STEEP LOW/MID LEVEL LAPSE RATES HAVE DEVELOPED WITH SHALLOW COOL LAYER AND DAYTIME HEATING AND HAS LED TO CU FIELD DEVELOPING OVER THE SOUTHERN PART OF OUR CWA. AS NOSE OF JET MOVES ACROSS CENTRAL NEBRASKA THERE MAY BE ENOUGH FORCING ALONG WITH THIS WEAKLY UNSTABLE MID LAYER FOR A FEW SPRINKLES TO MOVE INTO THE NORTHEAST CORNER OF OUR CWA...OTHERWISE WE ARE ONLY LOOKING AT A PERIOD OF MID LEVEL CU OVER OUR CWA THIS AFTERNOON. IF THERE IS A BETTER SHOWER WE COULD SEE A FLURRY INSTEAD OF SPRINKLE THROUGH...BUT I DIDN`T SEE A REASON TO GET THAT CUTE CONSIDERING CONFIDENCE IS ALREADY LOW ON PRECIP REACHING THE GROUND IN OUR NE CWA. ANOTHER HARD FREEZE IS EXPECTED TONIGHT...THOUGH THERE WILL BE SOME MODERATION OF THE AIR MASS ALOFT AS HIGH PRESSURE SHIFTS EAST AND W-SW WINDS DEVELOP LATE TONIGHT. MONDAY...CONTINUE MODERATION OF THE AIR MASS IS EXPECTED WITH DAYTIME HIGHS REACHING SEASONAL VALUES IN THE 60S ACROSS THE CWA. SNOW PACK COULD STILL IMPACT LOCATIONS IN THE NORTH...HOWEVER WITH SW WINDS COMING FROM SNOW FREE LOCATIONS WE SHOULD SEE A QUICK MELTING OF SNOW. MAIN CONCERN FOR MONDAY WILL BE POTENTIAL FOR RED FLAG CONDITIONS WITH WINDY CONDITIONS DEVELOPING EARLY IN THE WEST AND GOOD MIXING SUPPORTING LOWER TD VALUES ACROSS THE SOUTH. MODEL OUTPUT GENERALLY SUPPORTS A DECREASING TREND IN THE WEST IN THE AFTERNOON AS GRADIENT SHIFTS EAST...SO THERE MAY ONLY BE A SMALL WINDOW FOR WIND/RH CROSSOVER. OF COURSE THERE IS ALSO THE QUESTION OF WHETHER FUELS WILL BE CURED AFTER RECENT PRECIP (ESPECIALLY OVER LOCATIONS WITH LINGERING SNOW PACK). WITH TOO MUCH UNCERTAINTY I DECIDED AGAINST ISSUANCE OF FIRE WEATHER WATCH AT THIS TIME. .LONG TERM...(THURSDAY THROUGH SUNDAY) ISSUED AT 242 AM MDT MON APR 14 2014 THE THURSDAY THROUGH SUNDAY PERIOD WILL START OUT WITH AN UPPER LEVEL TROUGH OVER THE TRI-STATE AREA. THE BEST CHANCES LOOK TO BE OVER THE EASTERN HALF OF THE AREA WHERE THE LOW LEVEL JET WILL BE AHEAD OF THE MAIN UPPER LEVEL TROUGH. DESPITE HIGH TEMPERATURES AROUND 40...WET BULB ZERO HEIGHTS INDICATE THE PRECIP. WILL BE SNOW. THE FAIRLY WARM TEMPERATURES FOR SNOWFALL SHOULD ALLOW THE SNOW TO BE WETTER THAN NORMAL FOR THE AREA. SOUNDINGS ACROSS THE AREA DO NOT INDICATE ANY CONVECTIVE INSTABILITY EXCEPT IN THE LOWEST 100 MB OR SO WHICH WOULD KEEP SNOWFALL RATES ON THE LIGHT SIDE. THE WARM GROUND TEMPERATURES AND LIGHT SNOWFALL RATES SHOULD ALLOW THE SNOW TO MELT AS IT FALLS SO DO NOT ANTICIPATE MUCH MORE THAN AN INCH OR SO OF ACCUMULATIONS OVER THE EAST HALF WITH LESS TO THE WEST. THURSDAY NIGHT MODELS DISAGREE WITH HOW FAST THE TROUGH WILL MOVE EAST OF THE AREA...BUT GENERALLY AGREE THE TROUGH WILL BE EAST OF THE AREA BY MIDNIGHT. BEHIND THE UPPER LEVEL TROUGH A SHORT WAVE RIDGE WILL MOVE OVER THE AREA...BRINGING A WARM FRONT INTO THE AREA FRIDAY. OVER THE WEEKEND THE SHORT WAVE RIDGE MOVES EAST WITH A SPLIT UPPER LEVEL FLOW DEVELOPING BEHIND IT. AN UPPER LEVEL RIDGE WILL BUILD OVER THE GREAT BASIN WITH A TROUGH ALSO DEEPENING OVER THE DESERT SOUTHWEST. AHEAD OF THE SPLIT UPPER LEVEL FLOW A SHORT WAVE TROUGH WILL MOVE ACROSS THE AREA BRINGING A LOW CHANCE FOR SOME RAINFALL WITH IT. BEHIND THE SHORT WAVE TROUGH A WEAK FRONT WILL MOVE THROUGH THE AREA. TEMPERATURES FOR THE PERIOD WILL START OUT BELOW NORMAL THEN WARM TO 20 DEGREES ABOVE NORMAL BY THE START OF NEXT WEEK. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1133 AM MDT MON APR 14 2014 LAYER OF CU 3000-5000KFT AGL HAS DEVELOPED NEAR GLD WITH WEAKLY UNSTABLE LAYER ASSOCIATED WITH DAYTIME HEATING...AND A SECOND AREA OF CU ASSOCIATED THE WEAK UPPER LEVEL DISTURBANCE WILL MOVE OUT OF NEBRASKA OVER KMCK. CONDITIONS ARE EXPECTED TO REMAIN VFR WITH THESE CLOUDS CLEARING AROUND 00Z WITH LOSS OF DAYTIME HEATING. NW WINDS GUSTING TO 25KT AT BOTH TERMINALS WILL DIMINISH AROUND SUNSET. WINDS SHOULD SHIFT TO THE WEST THEN SOUTHWEST WITH LEE TROUGH BEGINNING TO BUILD OVERNIGHT...THEN INCREASE FROM THE WEST TUESDAY MORNING. EXPECT GUSTS AT KGLD AROUND SUNRISE TUESDAY TO 25KT...POSSIBLY HIGHER. AT KMCK...WINDS WILL LIKELY INCREASE OUTSIDE THE CURRENT TAF PERIOD. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...DR LONG TERM...JTL AVIATION...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1138 PM MDT SUN APR 13 2014 .UPDATE... ISSUED AT 1129 PM MDT SUN APR 13 2014 SNOWFALL IS DECREASING IN INTENSITY AND COVERAGE. DO NOT EXPECT MUCH MORE ACCUMULATION. SO WENT AHEAD AND CANCELLED THE WINTER WEATHER ADVISORY. UPDATE ISSUED AT 901 PM MDT SUN APR 13 2014 NEWER MODEL DATA IS CONFIRMING WHAT RECENT OBSERVATION AND RADAR TRENDS HAVE SHOWING WITH THE DECREASING TREND OF THE SNOW. HAVE CANCELLED THE WINTER WEATHER ADVISORY FOR RED WILLOW...DECATUR AND NORTON COUNTIES. UPDATE ISSUED AT 803 PM MDT SUN APR 13 2014 HAVE RECENTLY COMPLETED A COUPLE OF UPDATES. HAVE ALLOWED THE WIND ADVISORY TO EXPIRE WITH WINDS BELOW CRITERIA. REST OF FORECAST LOOKING ON TRACK. HAVE ADJUSTED WEATHER AND POPS TO REFLECT THE TRENDS SEEN ON OBSERVATIONS...SATELLITE AND RADAR. WINTER WEATHER ADVISORY DOING FINE WITH EXPECTED LIFT TO CONTINUE THROUGH MIDNIGHT. EASTERN END OF THE ADVISORY MAY NOT GET TOO MUCH MORE SNOW BUT WILL KEEP IT WITH THE EXPECTED INTENSITY OF SNOW COMBINED WITH WHAT HAS ALREADY AND THE WINDY CONDITIONS. && .SHORT TERM...(THIS AFTERNOON THROUGH MONDAY) ISSUED AT 203 PM MDT SUN APR 13 2014 LATEST WV IMAGERY AND RAP H5 ANALYSIS SHOW LARGE UPPER LEVEL TROUGH ACROSS NORTHERN/CENTRAL US WITH TWO DISTINCT H5/H7 CIRCULATIONS OVER THE PLAINS AND CENTRAL ROCKIES. THE FIRST CIRCULATION IS ASSOCIATED THE H5/H7 LOW NO OVER CENTRAL/EASTERN NEBRASKA...RESPONSIBLE FOR DEFORMATION BAND OF SNOW THAT FORMED OVER NORTHEAST COLORADO EARLY THIS MORNING AND IS NOW OVER THE NORTHERN PART OF OUR CWA. THE SECOND CIRCULATION IS ASSOCIATE WITH A SECOND CLOSED H7 LOW AND H5 TROUGH DEEPENING OVER WESTERN COLORADO. REGARDING WIND ADVISORY THIS AFTERNOON/EVENING...WINDS HAVE STRUGGLED TO APPROACH CRITERIA THOUGH THEY HAVE BEEN NEAR ADVISORY CRITERIA AT TIMES. THE PLAN IS TO HOLD ONTO THE ONGOING WIND ADVISORY FOR A FEW MORE HOURS AS THE BEST PRESSURE RISES ARE BEGINNING TO SHIFT TO THE SOUTH AND EAST...AND PROBABLY CANCEL THE ADVISORY BEFORE 00Z. REGARDING WINTER WEATHER ADVISORY...AS MENTIONED IN THE SYNOPSIS THERE ARE TWO DISTINCT UPPER LEVEL CIRCULATIONS RESPONSIBLE FOR BRINGING WINTRY WEATHER TO OUR CWA TODAY/TONIGHT. THE DEFORMATION BAND ASSOCIATED WITH THE CIRCULATION OVER NEBRASKA SHOULD CONTINUE TO TRANSITION NORTH AND EAST...WITH MAIN IMPACT OVER THE NORTHERN PART OF THE CWA WINDING DOWN AROUND 00Z. I COULD SEE US CANCELING THE NORTHERN PART OF THE ADVISORY EARLY (00Z-03Z) AS WE WILL LIKELY NOT SEE ADVISORY CRITERIA MET UP NORTH WITH THE 2ND UPPER LOW. THE SOUTHERN PART OF THE ADVISORY (KIT CARSON/CHEYENNE CO) HAVE AVOIDED THE BRUNT OF THIS FIRST WAVE...HOWEVER THE SECOND CIRCULATION WILL BEGIN TO BRING LIGHT TO MODERATE SNOW INTO EASTERN COLORADO THIS EVENING AND THIS IS WHEN THESE LOCATIONS MAY SEE THE GREATEST IMPACT. CONFIDENCE IS ACTUALLY HIGHER FOR KIT CARSON/CHEYENNE CO TO MEET ADVISORY CRITERIA THIS EVENING THAN SHERMAN. SHERMAN/WALLACE/GREELEY COULD BE CLOSE BASED ON LATEST MODEL OUTPUT...HOWEVER CONFIDENCE IS TOO LOW TO ADD WALLACE/GREELEY...OR CANCEL SHERMAN AT THIS POINT. WE WILL NEED TO MONITOR NEAR TERM TRENDS. PRECIP SHOULD QUICKLY WIND DOWN THIS EVENING IN THE NORTH AND THEN AFTER MIDNIGHT ACROSS THE SOUTH...WITH MAYBE SNOW LINGERING THROUGH MID MORNING MONDAY IN THE FAR SOUTH. REGARDING ANTICIPATED IMPACTS THIS AFTERNOON/EVENING...ADDITIONAL LIGHT SNOW ACCUMULATIONS ARE ANTICIPATED FOR MOST LOCATIONS...HOWEVER MODERATE-HEAVY ACCUMULATIONS ARE MOST LIKELY THIS EVENING OVER KIT CARSON/CHEYENNE COLORADO COUNTIES. WINDY CONDITIONS WILL CONTINUE...AND WILL CONTINUE BRING BLOWING SNOW CHANCES AND LOCALLY REDUCED VISIBILITIES THROUGH AROUND 03Z. LATE TONIGHT/MONDAY TEMPS...HARD FREEZE IS LIKELY WITH SUB FREEZING TEMPS ALREADY ACROSS MOST OF THE CWA...AND UPSTREAM TEMPS IN THE 23-25F ALREADY BEING REPORTED. TOO EARLY IN THE SEASON TO ISSUE FROST/FREEZE HIGHLIGHTS CONSIDERING CLIMATE NORMS FOR LAST FROST/FREEZE. AIR MASS WILL BEGIN TO MODERATE SOME MONDAY...HOWEVER HIGHS WILL REMAIN WELL BELOW NORMAL WITH VALUES IN THE 40S ACROSS THE CWA. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 210 PM MDT SUN APR 13 2014 A SHORT WAVE RIDGE MOVES OVER THE ROCKIES AND FLATTENS AS IT MOVES ACROSS THE HIGH PLAINS BETWEEN MONDAY NIGHT THROUGH TUESDAY NIGHT. TEMPERATES WILL WARM AND CONDITIONS WILL DRY DURING THAT TIME. BETWEEN LATE WEDNESDAY THROUGH THURSDAY NIGHT ANOTHER LOW PRESSURE SYSTEM WILL MOVE THROUGH THE ROCKIES AND HIGH PLAINS REGIONS...BRINGING ANOTHER ROUND OF COOLER TEMPERATURES AND A CHANCE OF PRECIPITATION TO THE CENTRAL HIGH PLAINS. A MIXTURE OF RAIN AND SNOW IS EXPECTED WITH THIS SYSTEM. MODEL SOLUTIONS BECOME MORE DIVERGENT BETWEEN FRIDAY AND SUNDAY...BUT THE CONSENSUS IS CONDITIONS WILL BE DRY AND WARMER WITH TEMPERATURES NEAR AVERAGE FOR THIS TIME OF YEAR. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1129 PM MDT SUN APR 13 2014 VFR CONDITIONS HAVE BEGUN AT KMCK AND WILL SOON FOLLOW AT KGLD. VFR CONDITIONS WILL THEN CONTINUE FOR THE REST OF THE PERIOD. THERE WILL BE A BRIEF REPRIEVE IN THE GUSTY WINDS LATER ON TONIGHT BEFORE INCREASING AND BECOMING GUSTY AROUND MID MORNING. THESE WINDS WILL CONTINUE UNTIL NEAR SUNSET. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ UPDATE...BULLER SHORT TERM...DR LONG TERM...LOCKHART AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1145 PM CDT Sun Apr 13 2014 ...Update to aviation forecast discussion... .SHORT TERM...(This Evening through Monday) Issued at 326 PM CDT SUN APR 13 2014 20Z water vapor imagery shows a shortwave lifting across eastern KS as another wave digs south towards the four corners region. This initial wave has sparked a line of thunderstorms to form along a cold front that is surging southeast through the forecast area. Much of the short range guidance is pointing towards the convection to be east of the forecast area by 7 pm, which fits in with current radar trends. Therefore have lowered pops for this evening and removed mention of thunder. There is a band of snow across NEB. The HRRR and RAP suggest the tail end of this precip may move east along the NEB state line through the evening as the first shortwave lifts northeast. Precip accumulations with this should be fairly light as the better mid level frontogenesis stays mainly to the north. However as the second shortwave comes out of the Rockies late tonight and through the morning Monday, this frontogenetical band redevelops south and most guidance is pointing at a band of snow moving over east central KS. The frontogenesis looks strong enough for a decent band of snow and possible accumulations around an inch through late morning Monday. This will be highly dependent on the intensity of the snowfall however since ground temps remain relatively warm. If the band produces higher snowfall rates, some parts of east central KS could see accumulations a little higher. In between the convection this afternoon and the frontogenetical precip overnight, think there will be a lull in the precip and have tapered pops down this evening. Models show saturation in the lower levels hinting at the possibility for some drizzle which could be freezing depending on surface temps. However the conditions for drizzle do not look to persist for long as some mid level drying occurs before the next shortwave moves in and saturates the column. Overall am not to excited about the prospects for drizzle but can`t rule out the chance so will include a mention in the forecast. Lows tonight should fall into the lower 30s due to strong cold air advection behind the front. Temps in central NEB have already fallen into the upper 20s suggesting my lows may not be cool enough. In any case, freezing temps look likely tonight and will issue as freeze warning as we have entered the locally defined growing season. Cold air advection persists through the morning Monday so highs are not expected to warm much. However think clouds will eventually clear out by the afternoon so some insolation may help to warm highs into the 40s. .LONG TERM...(Monday Night through Sunday) Issued at 326 PM CDT SUN APR 13 2014 Monday night through Wednesday looks dry as the central plains see dry northwest flow develop ahead of the next wave expected to dig into the plains by Thursday. The medium range models seem to be in some agreement with timing of the next wave therefore have trended pops up for Thursday and Thursday night. There does not appear to be much instability with this system as warm moist are is slow to return. However there does appear to be another shot of cold air moving in Thursday night which could cause a brief change over to snow before the precip comes to an end. Therefore have maintained a mention of rain and snow for Thursday night. While less certain, there are indications of a southern stream wave trying to phase with a northern stream wave over the area Sunday. Confidence is low since the GFS struggles to advect moisture this far north. However with the ECMWF breaking out some QPF, will insert some low (20-30%) POPs Saturday night and Sunday. A hard freeze looks likely Tuesday morning as skies clear out and surface ridging moves over the region. Therefore have continued with lows in the lower to middle 20s and will post a freeze warning through Tuesday morning too. Southerly flow returns for Wednesday helping to moderate the cool temps before the next cold front moves in Thursday and knocks temps back down into the 40s and 50s for Thursday and Friday. With a split flow for the weekend and the northern stream remaining north, temps should moderate into the 60s for the weekend. && .AVIATION...(For the 06Z TAFs through 06Z Monday Night) Issued at 1132 PM CDT SUN APR 13 2014 MVFR conditions should persist through for the remainder of tonight. A band of snow will develop over south central KS early tomorrow morning and move northeast towards the taf sites. MHK may be on the northern edge of the axis of snow therefore have shortened the period of snow there. There could be a brief period of moderate to heavy snow that would cause IFR vis but confidence for that occurring is low at this point. Conditions should improve to VFR after the snow band exits the taf sites. && .TOP WATCHES/WARNINGS/ADVISORIES... FREEZE WARNING until 10 AM CDT Monday FOR KSZ008>012-020>024-026- 034>040-054>056-058-059. FREEZE WARNING from 11 PM Monday to 9 AM CDT Tuesday FOR KSZ008>012-020>024-026-034>040-054>056-058-059. && $$ SHORT TERM...Wolters LONG TERM...Wolters AVIATION...Sanders
AREA FORECAST DISCUSSION
NWS JACKSON KY
138 PM EDT MON APR 14 2014 .UPDATE... ISSUED AT 1136 AM EDT MON APR 14 2014 A FEW UPDATES MADE TO THE FORECAST FOR TODAY. BASED ON THE LATEST SURFACE OBS AND EXPECTED TRENDS...DECIDED TO LOWER TODAYS HOURLY AND OVERALL HIGH TEMPERATURES BY 3 OR 4 DEGREES ACROSS THE BOARD. WITH MOIST GROUND...STEADY WINDS...AND PERSISTENT OVERCAST CLOUD COVER...DID NOT SEEM REASONABLE THAT PREVIOUS IN THE MID TO UPPER 70S AREA WIDE WERE REACHABLE. THE LATEST RADAR TRENDS AND MODEL DATA...PARTICULARLY THE HRRR...SEEMED TO SUPPORT THE CURRENT POPS FOR THE REST OF THE DAY. THE PRECIP CURRENTLY MOVING ACROSS THE AREA SEEMS TO HAVE A DISTINCT BACK EDGE THAT WILL BE THROUGH OUR AREA IN THE NEXT FEW HOURS. AFTER THAT IT APPEARS THAT WE WILL SEE A BREAK IN THE ACTION UNTIL LATER THIS EVENING A COLD FRONT AND UPPER TROUGH MOVE THROUGH THE AREA. WILL ALSO BE SENDING OUT UPDATED VERSIONS OF THE LAKE WIND ADVISORY AND FREEZE WATCH. WINDS ACROSS THE AREA SO FAR TODAY HAVE BEEN MEETING LAKE WIND CRITERIA AND THERE IS NO REASON TO BELIEVE THIS WILL CEASE TO BE THE CASE THE REST OF THE DAY. UPDATE ISSUED AT 702 AM EDT MON APR 14 2014 NO UPDATE PLANNED THIS MORNING. LATEST HRRR HAS STUCK TO ITS SCENARIO TODAY REGARDING SCATTERED LINE OF SHOWERS PUSHING ITS WAY ACROSS THE AREA TODAY. THESE SHOWERS ARE JUST NOW WORKING INTO THE I-75 CORRIDOR...AND THE CURRENT FORECAST HAS THIS COVERED WELL. NOT SURE IF WE WILL BE ABLE TO SQUEEZE OUT MUCH LIQUID WITH SUCH DRY AIR ENTRENCHED ACROSS THE AREA...BUT WE COULD SQUEEZE OUT A HUNDREDTH OR TWO THROUGH THE MORNING. && .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 328 AM EDT MON APR 14 2014 THERE ARE SEVERAL FEATURES OF INTEREST THIS MORNING UPSTREAM. A WEAK MID LEVEL TROUGH IS NOW MOVING INTO THE NORTHERN OHIO RIVER VALLEY WITH A SURFACE LOW PUSHING INTO THE GREAT LAKES REGION. THIS INITIAL TROUGH HAD BEEN RESPONSIBLE FOR AN ORGANIZED AREA OF SHOWERS AND STORMS AS IT PUSHED INTO WESTERN KENTUCKY OVERNIGHT. AS THIS ACTIVITY CONTINUES TO PUSH EAST THIS MORNING IT WILL ENCOUNTER A MUCH MORE STABLE AND DRY AIR MASS AND WILL QUICKLY WEAKEN. HRRR HAS A GOOD HANDLE ON THIS AREA OF PRECIPITATION. AS IT REACHES EASTERN KENTUCKY...IT LOOKS LIKE THE ACTIVITY MAY BECOME MORE SCATTERED AND EVEN MORE SO AS IT PUSHES FURTHER EAST. WHILE A FASTER ONSET OF PRECIPITATION LOOKS LIKELY TODAY...IT ALSO LOOKS LIKE ONLY A LIMITED WINDOW FOR PRECIPITATION THROUGH EARLY AFTERNOON BEFORE WE DRY OUT AGAIN BY LATE AFTERNOON AND THIS EVENING AS SUBSIDENCE SPREADS BACK OVER THE AREA AHEAD OF THE NEXT TROUGH. THUS...GOING TO BACK OFF POPS TO MORE SCATTERED COVERAGE TODAY AS MANY AREAS...ESPECIALLY IN THE EAST MAY NOT MEASURE TODAY OR WILL LIKELY SEE VERY LIGHT RAINFALL. WINDS ARE THE OTHER CONCERN FOR TODAY AS WINDS ARE ALREADY GUSTING UP TO 30 MPH THIS MORNING. WITH THE WEAKENING SHOWERS SPREADING INTO THE AREA...WE MAY TAP INTO SOME HIGHER WINDS ALOFT WITH 40 KNOTS AROUND 900 MB. THIS MAY CREATE SOME VERY GUSTY CONDITIONS AS THIS BAND OF SHOWERS MOVES EAST THROUGH EARLY AFTERNOON. THUS...WENT AHEAD AND ISSUED A LAKE WIND ADVISORY THROUGH 23Z TODAY TO ACCOUNT FOR THESE WINDS. MEANWHILE...A SHARPER MID LEVEL TROUGH IS CONTINUING TO DIG OVER THE CENTRAL ROCKIES WITH A NORTHERN STREAM WAVE PUSHING INTO THE NORTHERN PLAINS. AS THESE TWO SYSTEMS PHASE AND MOVE EAST...IT WILL ACCELERATE THE COLD FRONT ACROSS EASTERN KENTUCKY LATE TONIGHT. WITH GOOD DYNAMICS IN PLACE...AND GOOD CONVERGENCE ALONG THE SURFACE BOUNDARY...WE WILL SEE WIDESPREAD PRECIPITATION DEVELOP AS THIS BOUNDARY MOVES EAST. A NARROW RIBBON OF INSTABILITY JUST AHEAD OF THE FRONT COULD LEND ITSELF TO SOME LIGHTNING OVERNIGHT. HOWEVER...INSTABILITY SHOULD REMAIN ELEVATED...AND POSE NO SEVERE THREAT. THE BIGGER STORY WILL BE THE RETURN OF MUCH COLDER AIR INTO EASTERN KENTUCKY FOR TUESDAY. IT DOES APPEAR SOME MOISTURE WILL LINGER BEHIND THE COLD FRONT YIELDING AN A BRIEF OPPORTUNITY FOR SOME SNOW TO MIX IN JUST BEFORE PRECIPITATION ENDS. MOST LOCATIONS WILL ESCAPE ANY SNOW ACCUMULATION AS THE GROUND WILL SIMPLY BE TOO WARM. THE EXCEPTION WILL BE IN THE HIGHEST TERRAIN ABOVE 2.5KFT AS COLDER SURFACE TEMPERATURES MAY ALLOW FOR BETTER ACCUMULATION POTENTIAL. WILL GO WITH UP TO 2 INCHES ON THE HIGHEST PEAKS IN SOUTHEAST KENTUCKY. PRECIPITATION WILL COME TO AN END THROUGH THE DAY TUESDAY...BUT SOME DRIZZLE OR FLURRIES COULD LINGER ACROSS THE HIGH TERRAIN IN THE SOUTHEAST INTO THE AFTERNOON OR EVENING HOURS. HIGHS WILL STRUGGLE TO REACH 40 ON TUESDAY...WITH HIGHS POSSIBLY OCCURRING EARLY IN THE DAY. .LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY) ISSUED AT 449 AM EDT MON APR 14 2014 A SURFACE RIDGE WILL BE MOVING OVER THE AREA WITH AN UNSEASONABLY COLD AND DRY AIR MASS AT THE START OF THE PERIOD. MODELS HAVE BEEN CONSISTENT IN THEIR SOLUTIONS...AGREEING ON CLEARING SKIES AND EASING WINDS LEADING TO A HARD FREEZE FOR MOST LOCATIONS...AND A FREEZE WATCH HAS BEEN ISSUED FOR TUESDAY NIGHT INTO WEDNESDAY MORNING. THE HIGH WILL SLIP TO OUR EAST WEDNESDAY AND THURSDAY...AND WEAK WARM AIR ADVECTION WILL RETURN. MOISTURE WILL BE SLOW TO INCREASE...SO EVEN THOUGH AFTERNOONS WILL BE MILDER...CLEAR TO PARTLY CLOUDY SKIES WILL ALLOW FOR A LARGE DIURNAL RANGE WITH CHILLY EARLY MORNINGS. FROST WILL BE EXPECTED FOR MANY LOCATIONS ON WEDNESDAY NIGHT...AND POSSIBLY ON THURSDAY NIGHT IN THE COLDEST VALLEYS. FROM FRIDAY THROUGH THE WEEKEND THE MODELS BECOME MORE DISPARATE AS TIME GOES BY. IN GENERAL TERMS...ANOTHER MID/UPPER LEVEL TROUGH WILL PROGRESS EAST ACROSS THE CONUS. COMPARED TO THE GFS...THE ECMWF IS STRONGER WITH THE SOUTHERN END OF THIS FEATURE NEAR THE GULF COAST. MEANWHILE...THE GFS IS WEAKER NEAR THE GULF COAST...BUT MUCH MORE AMPLIFIED ACROSS THE NORTH CENTRAL CONUS. THIS AFFECTS CORRESPONDING SURFACE LOW DEVELOPMENT. BOTH SCENARIOS BRING THE GREATEST POP ON FRIDAY NIGHT...BUT THE GFS IS MORE SUPPORTIVE OF PRECIP. THE DIFFERING SURFACE PATTERNS ALSO AFFECT HOW MUCH COLDER FLOWS SOUTHWARD DURING THE WEEKEND. SOME MEMBERS OF THE GFS ENSEMBLE VARY QUITE A BIT FROM THE OPERATIONAL RUN...AND LEND SUPPORT TO THE ECMWF PATTERN...BUT THE GFS ENSEMBLE MEAN SUPPORTS THE OPERATIONAL GFS. WITH ALL THIS IN MIND...WILL CONTINUE TO USE A GENERALIZED MODEL COMPROMISE...WITH A LOWER CONFIDENCE THAN NORMAL. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 137 PM EDT MON APR 14 2014 MAINLY VFR CONDITIONS EXPECTED THROUGH AROUND 4Z TONIGHT. THE ISSUE FOR AVIATORS TODAY WILL BE WINDS. SOUTHWESTERLY TO SOUTHEASTERLY WINDS OF 8 TO 15 KTS WITH GUSTS OF 20 TO 30 KTS WILL BE POSSIBLE THROUGH FOR THE REST OF THE DAY. BASED ON THE LATEST TRENDS IN RADAR BOTH OVER EASTERN KENTUCKY AND POINTS WESTWARD...IT APPEARS THAT THE REST OF THE DAY COULD BE RAIN FREE. IT LOOKS LIKE THE NEXT CHANCE OF PRECIPITATION MAY NOT ARRIVE UNTIL BETWEEN 4 AND 6Z TONIGHT AT THE TAF SITES. UNTIL THEN...THE AIRPORTS WILL CONTINUE TO EXPERIENCE OVERCAST CIGS OF 3-6K ACROSS THE BOARD. JKL WILL LIKELY SEE THE LOWEST CIGS THROUGH THIS EVENING. ONCE THE PRECIPITATION BEGINS...THE TAF SITES SHOULD BEGIN TO SEE MVFR CIGS...WITH IFR CIGS POSSIBLE WHEN WIDESPREAD LOW LEVEL CLOUD COVER AND RAIN AND SNOW SHOWERS BEGIN TO MOVE ACROSS THE AREA BETWEEN 11 AND 14Z ON TUESDAY. TUESDAYS WEATHER WILL FEATURE A MIX OF RAIN AND SNOW SHOWERS...WITH PERHAPS A LITTLE BIT OF SLEET EARLY IN MORNING. && .JKL WATCHES/WARNINGS/ADVISORIES... FREEZE WATCH FROM TUESDAY EVENING THROUGH WEDNESDAY MORNING FOR KYZ044-050>052-058>060-068-069-079-080-083>088-104-106>120. LAKE WIND ADVISORY UNTIL 7 PM EDT THIS EVENING FOR KYZ044- 050>052-058>060-068-069-079-080-083>088-104-106>120. && $$ UPDATE...AR SHORT TERM...KAS LONG TERM...HAL AVIATION...AR
AREA FORECAST DISCUSSION
NWS JACKSON KY
1136 AM EDT MON APR 14 2014 .UPDATE... ISSUED AT 1136 AM EDT MON APR 14 2014 A FEW UPDATES MADE TO THE FORECAST FOR TODAY. BASED ON THE LATEST SURFACE OBS AND EXPECTED TRENDS...DECIDED TO LOWER TODAYS HOURLY AND OVERALL HIGH TEMPERATURES BY 3 OR 4 DEGREES ACROSS THE BOARD. WITH MOIST GROUND...STEADY WINDS...AND PERSISTENT OVERCAST CLOUD COVER...DID NOT SEEM REASONABLE THAT PREVIOUS IN THE MID TO UPPER 70S AREA WIDE WERE REACHABLE. THE LATEST RADAR TRENDS AND MODEL DATA...PARTICULARLY THE HRRR...SEEMED TO SUPPORT THE CURRENT POPS FOR THE REST OF THE DAY. THE PRECIP CURRENTLY MOVING ACROSS THE AREA SEEMS TO HAVE A DISTINCT BACK EDGE THAT WILL BE THROUGH OUR AREA IN THE NEXT FEW HOURS. AFTER THAT IT APPEARS THAT WE WILL SEE A BREAK IN THE ACTION UNTIL LATER THIS EVENING A COLD FRONT AND UPPER TROUGH MOVE THROUGH THE AREA. WILL ALSO BE SENDING OUT UPDATED VERSIONS OF THE LAKE WIND ADVISORY AND FREEZE WATCH. WINDS ACROSS THE AREA SO FAR TODAY HAVE BEEN MEETING LAKE WIND CRITERIA AND THERE IS NO REASON TO BELIEVE THIS WILL CEASE TO BE THE CASE THE REST OF THE DAY. UPDATE ISSUED AT 702 AM EDT MON APR 14 2014 NO UPDATE PLANNED THIS MORNING. LATEST HRRR HAS STUCK TO ITS SCENARIO TODAY REGARDING SCATTERED LINE OF SHOWERS PUSHING ITS WAY ACROSS THE AREA TODAY. THESE SHOWERS ARE JUST NOW WORKING INTO THE I-75 CORRIDOR...AND THE CURRENT FORECAST HAS THIS COVERED WELL. NOT SURE IF WE WILL BE ABLE TO SQUEEZE OUT MUCH LIQUID WITH SUCH DRY AIR ENTRENCHED ACROSS THE AREA...BUT WE COULD SQUEEZE OUT A HUNDREDTH OR TWO THROUGH THE MORNING. && .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 328 AM EDT MON APR 14 2014 THERE ARE SEVERAL FEATURES OF INTEREST THIS MORNING UPSTREAM. A WEAK MID LEVEL TROUGH IS NOW MOVING INTO THE NORTHERN OHIO RIVER VALLEY WITH A SURFACE LOW PUSHING INTO THE GREAT LAKES REGION. THIS INITIAL TROUGH HAD BEEN RESPONSIBLE FOR AN ORGANIZED AREA OF SHOWERS AND STORMS AS IT PUSHED INTO WESTERN KENTUCKY OVERNIGHT. AS THIS ACTIVITY CONTINUES TO PUSH EAST THIS MORNING IT WILL ENCOUNTER A MUCH MORE STABLE AND DRY AIR MASS AND WILL QUICKLY WEAKEN. HRRR HAS A GOOD HANDLE ON THIS AREA OF PRECIPITATION. AS IT REACHES EASTERN KENTUCKY...IT LOOKS LIKE THE ACTIVITY MAY BECOME MORE SCATTERED AND EVEN MORE SO AS IT PUSHES FURTHER EAST. WHILE A FASTER ONSET OF PRECIPITATION LOOKS LIKELY TODAY...IT ALSO LOOKS LIKE ONLY A LIMITED WINDOW FOR PRECIPITATION THROUGH EARLY AFTERNOON BEFORE WE DRY OUT AGAIN BY LATE AFTERNOON AND THIS EVENING AS SUBSIDENCE SPREADS BACK OVER THE AREA AHEAD OF THE NEXT TROUGH. THUS...GOING TO BACK OFF POPS TO MORE SCATTERED COVERAGE TODAY AS MANY AREAS...ESPECIALLY IN THE EAST MAY NOT MEASURE TODAY OR WILL LIKELY SEE VERY LIGHT RAINFALL. WINDS ARE THE OTHER CONCERN FOR TODAY AS WINDS ARE ALREADY GUSTING UP TO 30 MPH THIS MORNING. WITH THE WEAKENING SHOWERS SPREADING INTO THE AREA...WE MAY TAP INTO SOME HIGHER WINDS ALOFT WITH 40 KNOTS AROUND 900 MB. THIS MAY CREATE SOME VERY GUSTY CONDITIONS AS THIS BAND OF SHOWERS MOVES EAST THROUGH EARLY AFTERNOON. THUS...WENT AHEAD AND ISSUED A LAKE WIND ADVISORY THROUGH 23Z TODAY TO ACCOUNT FOR THESE WINDS. MEANWHILE...A SHARPER MID LEVEL TROUGH IS CONTINUING TO DIG OVER THE CENTRAL ROCKIES WITH A NORTHERN STREAM WAVE PUSHING INTO THE NORTHERN PLAINS. AS THESE TWO SYSTEMS PHASE AND MOVE EAST...IT WILL ACCELERATE THE COLD FRONT ACROSS EASTERN KENTUCKY LATE TONIGHT. WITH GOOD DYNAMICS IN PLACE...AND GOOD CONVERGENCE ALONG THE SURFACE BOUNDARY...WE WILL SEE WIDESPREAD PRECIPITATION DEVELOP AS THIS BOUNDARY MOVES EAST. A NARROW RIBBON OF INSTABILITY JUST AHEAD OF THE FRONT COULD LEND ITSELF TO SOME LIGHTNING OVERNIGHT. HOWEVER...INSTABILITY SHOULD REMAIN ELEVATED...AND POSE NO SEVERE THREAT. THE BIGGER STORY WILL BE THE RETURN OF MUCH COLDER AIR INTO EASTERN KENTUCKY FOR TUESDAY. IT DOES APPEAR SOME MOISTURE WILL LINGER BEHIND THE COLD FRONT YIELDING AN A BRIEF OPPORTUNITY FOR SOME SNOW TO MIX IN JUST BEFORE PRECIPITATION ENDS. MOST LOCATIONS WILL ESCAPE ANY SNOW ACCUMULATION AS THE GROUND WILL SIMPLY BE TOO WARM. THE EXCEPTION WILL BE IN THE HIGHEST TERRAIN ABOVE 2.5KFT AS COLDER SURFACE TEMPERATURES MAY ALLOW FOR BETTER ACCUMULATION POTENTIAL. WILL GO WITH UP TO 2 INCHES ON THE HIGHEST PEAKS IN SOUTHEAST KENTUCKY. PRECIPITATION WILL COME TO AN END THROUGH THE DAY TUESDAY...BUT SOME DRIZZLE OR FLURRIES COULD LINGER ACROSS THE HIGH TERRAIN IN THE SOUTHEAST INTO THE AFTERNOON OR EVENING HOURS. HIGHS WILL STRUGGLE TO REACH 40 ON TUESDAY...WITH HIGHS POSSIBLY OCCURRING EARLY IN THE DAY. .LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY) ISSUED AT 449 AM EDT MON APR 14 2014 A SURFACE RIDGE WILL BE MOVING OVER THE AREA WITH AN UNSEASONABLY COLD AND DRY AIR MASS AT THE START OF THE PERIOD. MODELS HAVE BEEN CONSISTENT IN THEIR SOLUTIONS...AGREEING ON CLEARING SKIES AND EASING WINDS LEADING TO A HARD FREEZE FOR MOST LOCATIONS...AND A FREEZE WATCH HAS BEEN ISSUED FOR TUESDAY NIGHT INTO WEDNESDAY MORNING. THE HIGH WILL SLIP TO OUR EAST WEDNESDAY AND THURSDAY...AND WEAK WARM AIR ADVECTION WILL RETURN. MOISTURE WILL BE SLOW TO INCREASE...SO EVEN THOUGH AFTERNOONS WILL BE MILDER...CLEAR TO PARTLY CLOUDY SKIES WILL ALLOW FOR A LARGE DIURNAL RANGE WITH CHILLY EARLY MORNINGS. FROST WILL BE EXPECTED FOR MANY LOCATIONS ON WEDNESDAY NIGHT...AND POSSIBLY ON THURSDAY NIGHT IN THE COLDEST VALLEYS. FROM FRIDAY THROUGH THE WEEKEND THE MODELS BECOME MORE DISPARATE AS TIME GOES BY. IN GENERAL TERMS...ANOTHER MID/UPPER LEVEL TROUGH WILL PROGRESS EAST ACROSS THE CONUS. COMPARED TO THE GFS...THE ECMWF IS STRONGER WITH THE SOUTHERN END OF THIS FEATURE NEAR THE GULF COAST. MEANWHILE...THE GFS IS WEAKER NEAR THE GULF COAST...BUT MUCH MORE AMPLIFIED ACROSS THE NORTH CENTRAL CONUS. THIS AFFECTS CORRESPONDING SURFACE LOW DEVELOPMENT. BOTH SCENARIOS BRING THE GREATEST POP ON FRIDAY NIGHT...BUT THE GFS IS MORE SUPPORTIVE OF PRECIP. THE DIFFERING SURFACE PATTERNS ALSO AFFECT HOW MUCH COLDER FLOWS SOUTHWARD DURING THE WEEKEND. SOME MEMBERS OF THE GFS ENSEMBLE VARY QUITE A BIT FROM THE OPERATIONAL RUN...AND LEND SUPPORT TO THE ECMWF PATTERN...BUT THE GFS ENSEMBLE MEAN SUPPORTS THE OPERATIONAL GFS. WITH ALL THIS IN MIND...WILL CONTINUE TO USE A GENERALIZED MODEL COMPROMISE...WITH A LOWER CONFIDENCE THAN NORMAL. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 702 AM EDT MON APR 14 2014 MAINLY VFR CONDITIONS WILL LIKELY PERSIST THROUGH THIS EVENING. . THE MAIN AVIATION CONCERN TODAY WILL BE GUSTY SOUTH AS THEY COULD REACH AROUND 30 KNOTS AT TIMES THROUGH THE DAY. A FEW ISOLATED HIGHER WIND GUSTS COULD ALSO BE POSSIBLE IN AND AROUND SHOWERS WHICH WILL BE SPREADING ACROSS THE AREA TODAY. A SHARP WIND SHIFT IS ANTICIPATED TONIGHT AS A COLD FRONT PUSHES ACROSS EASTERN KENTUCKY. THIS WIND SHIFT WILL LIKELY OCCUR CLOSER TO MIDNIGHT OR LATER AS WINDS GO FROM THE SOUTH TO THE WEST AND NORTHWEST. IN ADDITION...WIDESPREAD PRECIPITATION WILL OVERSPREAD THE AREA LATE TONIGHT WITH CIGS COMING DOWN LATE TONIGHT TO MVFR OR LOWER. && .JKL WATCHES/WARNINGS/ADVISORIES... FREEZE WATCH FROM TUESDAY EVENING THROUGH WEDNESDAY MORNING FOR KYZ044-050>052-058>060-068-069-079-080-083>088-104-106>120. LAKE WIND ADVISORY UNTIL 7 PM EDT THIS EVENING FOR KYZ044- 050>052-058>060-068-069-079-080-083>088-104-106>120. && $$ UPDATE...AR SHORT TERM...KAS LONG TERM...HAL AVIATION...KAS
AREA FORECAST DISCUSSION
NWS JACKSON KY
703 AM EDT MON APR 14 2014 .UPDATE... ISSUED AT 702 AM EDT MON APR 14 2014 NO UPDATE PLANNED THIS MORNING. LATEST HRRR HAS STUCK TO ITS SCENARIO TODAY REGARDING SCATTERED LINE OF SHOWERS PUSHING ITS WAY ACROSS THE AREA TODAY. THESE SHOWERS ARE JUST NOW WORKING INTO THE I-75 CORRIDOR...AND THE CURRENT FORECAST HAS THIS COVERED WELL. NOT SURE IF WE WILL BE ABLE TO SQUEEZE OUT MUCH LIQUID WITH SUCH DRY AIR ENTRENCHED ACROSS THE AREA...BUT WE COULD SQUEEZE OUT A HUNDREDTH OR TWO THROUGH THE MORNING. && .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 328 AM EDT MON APR 14 2014 THERE ARE SEVERAL FEATURES OF INTEREST THIS MORNING UPSTREAM. A WEAK MID LEVEL TROUGH IS NOW MOVING INTO THE NORTHERN OHIO RIVER VALLEY WITH A SURFACE LOW PUSHING INTO THE GREAT LAKES REGION. THIS INITIAL TROUGH HAD BEEN RESPONSIBLE FOR AN ORGANIZED AREA OF SHOWERS AND STORMS AS IT PUSHED INTO WESTERN KENTUCKY OVERNIGHT. AS THIS ACTIVITY CONTINUES TO PUSH EAST THIS MORNING IT WILL ENCOUNTER A MUCH MORE STABLE AND DRY AIR MASS AND WILL QUICKLY WEAKEN. HRRR HAS A GOOD HANDLE ON THIS AREA OF PRECIPITATION. AS IT REACHES EASTERN KENTUCKY...IT LOOKS LIKE THE ACTIVITY MAY BECOME MORE SCATTERED AND EVEN MORE SO AS IT PUSHES FURTHER EAST. WHILE A FASTER ONSET OF PRECIPITATION LOOKS LIKELY TODAY...IT ALSO LOOKS LIKE ONLY A LIMITED WINDOW FOR PRECIPITATION THROUGH EARLY AFTERNOON BEFORE WE DRY OUT AGAIN BY LATE AFTERNOON AND THIS EVENING AS SUBSIDENCE SPREADS BACK OVER THE AREA AHEAD OF THE NEXT TROUGH. THUS...GOING TO BACK OFF POPS TO MORE SCATTERED COVERAGE TODAY AS MANY AREAS...ESPECIALLY IN THE EAST MAY NOT MEASURE TODAY OR WILL LIKELY SEE VERY LIGHT RAINFALL. WINDS ARE THE OTHER CONCERN FOR TODAY AS WINDS ARE ALREADY GUSTING UP TO 30 MPH THIS MORNING. WITH THE WEAKENING SHOWERS SPREADING INTO THE AREA...WE MAY TAP INTO SOME HIGHER WINDS ALOFT WITH 40 KNOTS AROUND 900 MB. THIS MAY CREATE SOME VERY GUSTY CONDITIONS AS THIS BAND OF SHOWERS MOVES EAST THROUGH EARLY AFTERNOON. THUS...WENT AHEAD AND ISSUED A LAKE WIND ADVISORY THROUGH 23Z TODAY TO ACCOUNT FOR THESE WINDS. MEANWHILE...A SHARPER MID LEVEL TROUGH IS CONTINUING TO DIG OVER THE CENTRAL ROCKIES WITH A NORTHERN STREAM WAVE PUSHING INTO THE NORTHERN PLAINS. AS THESE TWO SYSTEMS PHASE AND MOVE EAST...IT WILL ACCELERATE THE COLD FRONT ACROSS EASTERN KENTUCKY LATE TONIGHT. WITH GOOD DYNAMICS IN PLACE...AND GOOD CONVERGENCE ALONG THE SURFACE BOUNDARY...WE WILL SEE WIDESPREAD PRECIPITATION DEVELOP AS THIS BOUNDARY MOVES EAST. A NARROW RIBBON OF INSTABILITY JUST AHEAD OF THE FRONT COULD LEND ITSELF TO SOME LIGHTNING OVERNIGHT. HOWEVER...INSTABILITY SHOULD REMAIN ELEVATED...AND POSE NO SEVERE THREAT. THE BIGGER STORY WILL BE THE RETURN OF MUCH COLDER AIR INTO EASTERN KENTUCKY FOR TUESDAY. IT DOES APPEAR SOME MOISTURE WILL LINGER BEHIND THE COLD FRONT YIELDING AN A BRIEF OPPORTUNITY FOR SOME SNOW TO MIX IN JUST BEFORE PRECIPITATION ENDS. MOST LOCATIONS WILL ESCAPE ANY SNOW ACCUMULATION AS THE GROUND WILL SIMPLY BE TOO WARM. THE EXCEPTION WILL BE IN THE HIGHEST TERRAIN ABOVE 2.5KFT AS COLDER SURFACE TEMPERATURES MAY ALLOW FOR BETTER ACCUMULATION POTENTIAL. WILL GO WITH UP TO 2 INCHES ON THE HIGHEST PEAKS IN SOUTHEAST KENTUCKY. PRECIPITATION WILL COME TO AN END THROUGH THE DAY TUESDAY...BUT SOME DRIZZLE OR FLURRIES COULD LINGER ACROSS THE HIGH TERRAIN IN THE SOUTHEAST INTO THE AFTERNOON OR EVENING HOURS. HIGHS WILL STRUGGLE TO REACH 40 ON TUESDAY...WITH HIGHS POSSIBLY OCCURRING EARLY IN THE DAY. .LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY) ISSUED AT 449 AM EDT MON APR 14 2014 A SURFACE RIDGE WILL BE MOVING OVER THE AREA WITH AN UNSEASONABLY COLD AND DRY AIR MASS AT THE START OF THE PERIOD. MODELS HAVE BEEN CONSISTENT IN THEIR SOLUTIONS...AGREEING ON CLEARING SKIES AND EASING WINDS LEADING TO A HARD FREEZE FOR MOST LOCATIONS...AND A FREEZE WATCH HAS BEEN ISSUED FOR TUESDAY NIGHT INTO WEDNESDAY MORNING. THE HIGH WILL SLIP TO OUR EAST WEDNESDAY AND THURSDAY...AND WEAK WARM AIR ADVECTION WILL RETURN. MOISTURE WILL BE SLOW TO INCREASE...SO EVEN THOUGH AFTERNOONS WILL BE MILDER...CLEAR TO PARTLY CLOUDY SKIES WILL ALLOW FOR A LARGE DIURNAL RANGE WITH CHILLY EARLY MORNINGS. FROST WILL BE EXPECTED FOR MANY LOCATIONS ON WEDNESDAY NIGHT...AND POSSIBLY ON THURSDAY NIGHT IN THE COLDEST VALLEYS. FROM FRIDAY THROUGH THE WEEKEND THE MODELS BECOME MORE DISPARATE AS TIME GOES BY. IN GENERAL TERMS...ANOTHER MID/UPPER LEVEL TROUGH WILL PROGRESS EAST ACROSS THE CONUS. COMPARED TO THE GFS...THE ECMWF IS STRONGER WITH THE SOUTHERN END OF THIS FEATURE NEAR THE GULF COAST. MEANWHILE...THE GFS IS WEAKER NEAR THE GULF COAST...BUT MUCH MORE AMPLIFIED ACROSS THE NORTH CENTRAL CONUS. THIS AFFECTS CORRESPONDING SURFACE LOW DEVELOPMENT. BOTH SCENARIOS BRING THE GREATEST POP ON FRIDAY NIGHT...BUT THE GFS IS MORE SUPPORTIVE OF PRECIP. THE DIFFERING SURFACE PATTERNS ALSO AFFECT HOW MUCH COLDER FLOWS SOUTHWARD DURING THE WEEKEND. SOME MEMBERS OF THE GFS ENSEMBLE VARY QUITE A BIT FROM THE OPERATIONAL RUN...AND LEND SUPPORT TO THE ECMWF PATTERN...BUT THE GFS ENSEMBLE MEAN SUPPORTS THE OPERATIONAL GFS. WITH ALL THIS IN MIND...WILL CONTINUE TO USE A GENERALIZED MODEL COMPROMISE...WITH A LOWER CONFIDENCE THAN NORMAL. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 702 AM EDT MON APR 14 2014 MAINLY VFR CONDITIONS WILL LIKELY PERSIST THROUGH THIS EVENING. . THE MAIN AVIATION CONCERN TODAY WILL BE GUSTY SOUTH AS THEY COULD REACH AROUND 30 KNOTS AT TIMES THROUGH THE DAY. A FEW ISOLATED HIGHER WIND GUSTS COULD ALSO BE POSSIBLE IN AND AROUND SHOWERS WHICH WILL BE SPREADING ACROSS THE AREA TODAY. A SHARP WIND SHIFT IS ANTICIPATED TONIGHT AS A COLD FRONT PUSHES ACROSS EASTERN KENTUCKY. THIS WIND SHIFT WILL LIKELY OCCUR CLOSER TO MIDNIGHT OR LATER AS WINDS GO FROM THE SOUTH TO THE WEST AND NORTHWEST. IN ADDITION...WIDESPREAD PRECIPITATION WILL OVERSPREAD THE AREA LATE TONIGHT WITH CIGS COMING DOWN LATE TONIGHT TO MVFR OR LOWER. && .JKL WATCHES/WARNINGS/ADVISORIES... FREEZE WATCH FROM TUESDAY EVENING THROUGH WEDNESDAY MORNING FOR KYZ044-050>052-058>060-068-069-079-080-083>088-104-106>120. LAKE WIND ADVISORY UNTIL 7 PM EDT THIS EVENING FOR KYZ044- 050>052-058>060-068-069-079-080-083>088-104-106>120. && $$ UPDATE...KAS SHORT TERM...KAS LONG TERM...HAL AVIATION...KAS
AREA FORECAST DISCUSSION
NWS JACKSON KY
449 AM EDT MON APR 14 2014 .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 328 AM EDT MON APR 14 2014 THERE ARE SEVERAL FEATURES OF INTEREST THIS MORNING UPSTREAM. A WEAK MID LEVEL TROUGH IS NOW MOVING INTO THE NORTHERN OHIO RIVER VALLEY WITH A SURFACE LOW PUSHING INTO THE GREAT LAKES REGION. THIS INITIAL TROUGH HAD BEEN RESPONSIBLE FOR AN ORGANIZED AREA OF SHOWERS AND STORMS AS IT PUSHED INTO WESTERN KENTUCKY OVERNIGHT. AS THIS ACTIVITY CONTINUES TO PUSH EAST THIS MORNING IT WILL ENCOUNTER A MUCH MORE STABLE AND DRY AIR MASS AND WILL QUICKLY WEAKEN. HRRR HAS A GOOD HANDLE ON THIS AREA OF PRECIPITATION. AS IT REACHES EASTERN KENTUCKY...IT LOOKS LIKE THE ACTIVITY MAY BECOME MORE SCATTERED AND EVEN MORE SO AS IT PUSHES FURTHER EAST. WHILE A FASTER ONSET OF PRECIPITATION LOOKS LIKELY TODAY...IT ALSO LOOKS LIKE ONLY A LIMITED WINDOW FOR PRECIPITATION THROUGH EARLY AFTERNOON BEFORE WE DRY OUT AGAIN BY LATE AFTERNOON AND THIS EVENING AS SUBSIDENCE SPREADS BACK OVER THE AREA AHEAD OF THE NEXT TROUGH. THUS...GOING TO BACK OFF POPS TO MORE SCATTERED COVERAGE TODAY AS MANY AREAS...ESPECIALLY IN THE EAST MAY NOT MEASURE TODAY OR WILL LIKELY SEE VERY LIGHT RAINFALL. WINDS ARE THE OTHER CONCERN FOR TODAY AS WINDS ARE ALREADY GUSTING UP TO 30 MPH THIS MORNING. WITH THE WEAKENING SHOWERS SPREADING INTO THE AREA...WE MAY TAP INTO SOME HIGHER WINDS ALOFT WITH 40 KNOTS AROUND 900 MB. THIS MAY CREATE SOME VERY GUSTY CONDITIONS AS THIS BAND OF SHOWERS MOVES EAST THROUGH EARLY AFTERNOON. THUS...WENT AHEAD AND ISSUED A LAKE WIND ADVISORY THROUGH 23Z TODAY TO ACCOUNT FOR THESE WINDS. MEANWHILE...A SHARPER MID LEVEL TROUGH IS CONTINUING TO DIG OVER THE CENTRAL ROCKIES WITH A NORTHERN STREAM WAVE PUSHING INTO THE NORTHERN PLAINS. AS THESE TWO SYSTEMS PHASE AND MOVE EAST...IT WILL ACCELERATE THE COLD FRONT ACROSS EASTERN KENTUCKY LATE TONIGHT. WITH GOOD DYNAMICS IN PLACE...AND GOOD CONVERGENCE ALONG THE SURFACE BOUNDARY...WE WILL SEE WIDESPREAD PRECIPITATION DEVELOP AS THIS BOUNDARY MOVES EAST. A NARROW RIBBON OF INSTABILITY JUST AHEAD OF THE FRONT COULD LEND ITSELF TO SOME LIGHTNING OVERNIGHT. HOWEVER...INSTABILITY SHOULD REMAIN ELEVATED...AND POSE NO SEVERE THREAT. THE BIGGER STORY WILL BE THE RETURN OF MUCH COLDER AIR INTO EASTERN KENTUCKY FOR TUESDAY. IT DOES APPEAR SOME MOISTURE WILL LINGER BEHIND THE COLD FRONT YIELDING AN A BRIEF OPPORTUNITY FOR SOME SNOW TO MIX IN JUST BEFORE PRECIPITATION ENDS. MOST LOCATIONS WILL ESCAPE ANY SNOW ACCUMULATION AS THE GROUND WILL SIMPLY BE TOO WARM. THE EXCEPTION WILL BE IN THE HIGHEST TERRAIN ABOVE 2.5KFT AS COLDER SURFACE TEMPERATURES MAY ALLOW FOR BETTER ACCUMULATION POTENTIAL. WILL GO WITH UP TO 2 INCHES ON THE HIGHEST PEAKS IN SOUTHEAST KENTUCKY. PRECIPITATION WILL COME TO AN END THROUGH THE DAY TUESDAY...BUT SOME DRIZZLE OR FLURRIES COULD LINGER ACROSS THE HIGH TERRAIN IN THE SOUTHEAST INTO THE AFTERNOON OR EVENING HOURS. HIGHS WILL STRUGGLE TO REACH 40 ON TUESDAY...WITH HIGHS POSSIBLY OCCURRING EARLY IN THE DAY. .LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY) ISSUED AT 449 AM EDT MON APR 14 2014 A SURFACE RIDGE WILL BE MOVING OVER THE AREA WITH AN UNSEASONABLY COLD AND DRY AIR MASS AT THE START OF THE PERIOD. MODELS HAVE BEEN CONSISTENT IN THEIR SOLUTIONS...AGREEING ON CLEARING SKIES AND EASING WINDS LEADING TO A HARD FREEZE FOR MOST LOCATIONS...AND A FREEZE WATCH HAS BEEN ISSUED FOR TUESDAY NIGHT INTO WEDNESDAY MORNING. THE HIGH WILL SLIP TO OUR EAST WEDNESDAY AND THURSDAY...AND WEAK WARM AIR ADVECTION WILL RETURN. MOISTURE WILL BE SLOW TO INCREASE...SO EVEN THOUGH AFTERNOONS WILL BE MILDER...CLEAR TO PARTLY CLOUDY SKIES WILL ALLOW FOR A LARGE DIURNAL RANGE WITH CHILLY EARLY MORNINGS. FROST WILL BE EXPECTED FOR MANY LOCATIONS ON WEDNESDAY NIGHT...AND POSSIBLY ON THURDAY NIGHT IN THE COLDEST VALLEYS. FROM FRIDAY THROUGH THE WEEKEND THE MODELS BECOME MORE DISPARATE AS TIME GOES BY. IN GENERAL TERMS...ANOTHER MID/UPPER LEVEL TROUGH WILL PROGRESS EAST ACROSS THE CONUS. COMPARED TO THE GFS...THE ECMWF IS STRONGER WITH THE SOUTHERN END OF THIS FEATURE NEAR THE GULF COAST. MEANWHILE...THE GFS IS WEAKER NEAR THE GULF COAST...BUT MUCH MORE AMPLIFIED ACROSS THE NORTH CENTRAL CONUS. THIS AFFECTS CORRESPONDING SURFACE LOW DEVELOPMENT. BOTH SCENARIOS BRING THE GREATEST POP ON FRIDAY NIGHT...BUT THE GFS IS MORE SUPPORTIVE OF PRECIP. THE DIFFERING SURFACE PATTERNS ALSO AFFECT HOW MUCH COLDER FLOWS SOUTHWARD DURING THE WEEKEND. SOME MEMBERS OF THE GFS ENSEMBLE VARY QUITE A BIT FROM THE OPERATIONAL RUN...AND LEND SUPPORT TO THE ECMWF PATTERN...BUT THE GFS ENSEMBLE MEAN SUPPORTS THE OPERATIONAL GFS. WITH ALL THIS IN MIND...WILL CONTINUE TO USE A GENERALIZED MODEL COMPROMISE...WITH A LOWER CONFIDENCE THAN NORMAL. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 232 AM EDT MON APR 14 2014 VFR CONDITIONS WILL LIKELY PERSIST THROUGH THE TAF FORECAST PERIOD. THE MAIN AVIATION CONCERN WILL BE THE POSSIBILITY OF SOME LOW LEVEL WIND SHEAR THROUGH THE REMAINDER OF THE OVERNIGHT HOURS. THEN WINDS WILL RAMP UP BY MORNING WITH GUSTY SOUTH WINDS ANTICIPATED AND THESE GUSTS COULD REACH AROUND 30 KNOTS AT TIMES THROUGH THE DAY. A FEW ISOLATED HIGHER WIND GUSTS COULD ALSO BE POSSIBLE IN AND AROUND SHOWERS WHICH WILL BE ARRIVING AROUND DAYBREAK IN THE WEST. A SHARP WIND SHIFT IS ANTICIPATED TONIGHT AS A COLD FRONT PUSHES ACROSS EASTERN KENTUCKY. THIS WIND SHIFT WILL LIKELY OCCUR CLOSER TO MIDNIGHT OR LATER AS WINDS GO FROM THE SOUTH TO THE WEST AND NORTHWEST. IN ADDITION...WIDESPREAD PRECIPITATION WILL OVERSPREAD THE AREA LATE TONIGHT WITH CIGS COMING DOWN LATE TONIGHT TO MVFR OR LOWER. && .JKL WATCHES/WARNINGS/ADVISORIES... FREEZE WATCH FROM TUESDAY EVENING THROUGH WEDNESDAY MORNING FOR KYZ044-050>052-058>060-068-069-079-080-083>088-104-106>120. LAKE WIND ADVISORY UNTIL 7 PM EDT THIS EVENING FOR KYZ044- 050>052-058>060-068-069-079-080-083>088-104-106>120. && $$ SHORT TERM...KAS LONG TERM...HAL AVIATION...KAS
AREA FORECAST DISCUSSION
NWS JACKSON KY
328 AM EDT MON APR 14 2014 .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 328 AM EDT MON APR 14 2014 THERE ARE SEVERAL FEATURES OF INTEREST THIS MORNING UPSTREAM. A WEAK MID LEVEL TROUGH IS NOW MOVING INTO THE NORTHERN OHIO RIVER VALLEY WITH A SURFACE LOW PUSHING INTO THE GREAT LAKES REGION. THIS INITIAL TROUGH HAD BEEN RESPONSIBLE FOR AN ORGANIZED AREA OF SHOWERS AND STORMS AS IT PUSHING INTO WESTERN KENTUCKY OVERNIGHT. AS THIS ACTIVITY CONTINUES TO PUSH EAST THIS MORNING IT WILL ENCOUNTER A MUCH MORE STABLE AND DRY AIRMASS AND WILL QUICKLY WEAKEN. HRRR HAS A GOOD HANDLE ON THIS AREA OF PRECIPITATION. AS IT REACHES EASTERN KENTUCKY...IT LOOKS LIKE THE ACTIVITY MAY BECOME MORE SCATTERED AND EVEN MORE SO AS IT PUSHES FURTHER EAST. WHILE A FASTER ONSET OF PRECIPITATION LOOKS LIKELY TODAY...IT ALSO LOOKS LIKE ONLY A LIMITED WINDOW FOR PRECIPITATION THROUGH EARLY AFTERNOON BEFORE WE DRY OUT AGAIN BY LATE AFTERNOON AND THIS EVENING AS SUBSIDENCE SPREADS BACK OVER THE AREA AHEAD OF THE NEXT TROUGH. THUS...GOING TO BACK OFF POPS TO MORE SCATTERED COVERAGE TODAY AS MANY AREAS...ESPECIALLY IN THE EAST MAY NOT MEASURE TODAY OR WILL LIKELY SEE VERY LIGHT RAINFALL. WINDS ARE THE OTHER CONCERN FOR TODAY AS WINDS ARE ALREADY GUSTING UP TO 30 MPH THIS MORNING. WITH THE WEAKENING SHOWERS SPREADING INTO THE AREA...WE MAY TAP INTO SOME HIGHER WINDS ALOFT WITH 40 KNOTS AROUND 900 MB. THIS MAY CREATE SOME VERY GUSTY CONDITIONS AS THIS BAND OF SHOWERS MOVES EAST THROUGH EARLY AFTERNOON. THUS...WENT AHEAD AND ISSUED A LAKE WIND ADVISORY THROUGH 23Z TODAY TO ACCOUNT FOR THESE WINDS. MEANWHILE...A SHARPER MID LEVEL TROUGH IS CONTINUING TO DIG OVER THE CENTRAL ROCKIES WITH A NORTHERN STREAM WAVE PUSHING INTO THE NORTHERN PLAINS. AS THESE TWO SYSTEMS PHASE AND MOVE EAST...IT WILL ACCELERATE THE COLD FRONT ACROSS EASTERN KENTUCKY LATE TONIGHT. WITH GOOD DYNAMICS IN PLACE...AND GOOD CONVERGENCE ALONG THE SURFACE BOUNDARY...WE WILL SEE WIDESPREAD PRECIPITATION DEVELOP AS THIS BOUNDARY MOVES EAST. A NARROW RIBBON OF INSTABILITY JUST AHEAD OF THE FRONT COULD LEND ITSELF TO SOME LIGHTNING OVERNIGHT. HOWEVER...INSTABILITY SHOULD REMAIN ELEVATED...AND POSE NO SEVERE THREAT. THE BIGGER STORY WILL BE THE RETURN OF MUCH COLDER AIR INTO EASTERN KENTUCKY FOR TUESDAY. IT DOES APPEAR SOME MOISTURE WILL LINGER BEHIND THE COLD FRONT YIELDING AN A BRIEF OPPORTUNITY FOR SOME SNOW TO MIX IN JUST BEFORE PRECIPITATION ENDS. MOST LOCATIONS WILL ESCAPE ANY SNOW ACCUMULATION AS THE GROUND WILL SIMPLY BE TOO WARM. THE EXCEPTION WILL BE IN THE HIGHEST TERRAIN ABOVE 2.5KFT AS COLDER SURFACE TEMPERATURES MAY ALLOW FOR BETTER ACCUMULATION POTENTIAL. WILL GO WITH UP TO 2 INCHES ON THE HIGHEST PEAKS IN SOUTHEAST KENTUCKY. PRECIPITATION WILL COME TO AN END THROUGH THE DAY TUESDAY...BUT SOME DRIZZLE OR FLURRIES COULD LINGER ACROSS THE HIGH TERRAIN IN THE SOUTHEAST INTO THE AFTERNOON OR EVENING HOURS. HIGHS WILL STRUGGLE TO REACH 40 ON TUESDAY...WITH HIGHS POSSIBLY OCCURRING EARLY IN THE DAY. .LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY) ISSUED AT 328 AM EDT MON APR 14 2014 LONG TERM DISCUSSION WILL FOLLOW SHORTLY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 232 AM EDT MON APR 14 2014 VFR CONDITIONS WILL LIKELY PERSIST THROUGH THE TAF FORECAST PERIOD. THE MAIN AVIATION CONCERN WILL BE THE POSSIBILITY OF SOME LOW LEVEL WIND SHEAR THROUGH THE REMAINDER OF THE OVERNIGHT HOURS. THEN WINDS WILL RAMP UP BY MORNING WITH GUSTY SOUTH WINDS ANTICIPATED AND THESE GUSTS COULD REACH AROUND 30 KNOTS AT TIMES THROUGH THE DAY. A FEW ISOLATED HIGHER WIND GUSTS COULD ALSO BE POSSIBLE IN AND AROUND SHOWERS WHICH WILL BE ARRIVING AROUND DAYBREAK IN THE WEST. A SHARP WIND SHIFT IS ANTICIPATED TONIGHT AS A COLD FRONT PUSHES ACROSS EASTERN KENTUCKY. THIS WIND SHIFT WILL LIKELY OCCUR CLOSER TO MIDNIGHT OR LATER AS WINDS GO FROM THE SOUTH TO THE WEST AND NORTHWEST. IN ADDITION...WIDESPREAD PRECIPITATION WILL OVERSPREAD THE AREA LATE TONIGHT WITH CIGS COMING DOWN LATE TONIGHT TO MVFR OR LOWER. && .JKL WATCHES/WARNINGS/ADVISORIES... FREEZE WATCH FROM TUESDAY EVENING THROUGH WEDNESDAY MORNING FOR KYZ044-050>052-058>060-068-069-079-080-083>088-104-106>120. LAKE WIND ADVISORY UNTIL 7 PM EDT THIS EVENING FOR KYZ044- 050>052-058>060-068-069-079-080-083>088-104-106>120. && $$ SHORT TERM...KAS LONG TERM...HAL AVIATION...KAS
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
1050 AM CDT MON APR 14 2014 .DISCUSSION... STORM INTENSITIES ARE INCREASING...WITH ADDITIONAL CONVECTIVE DEVELOPMENT UPSTREAM...PROMPTING A SEVERE TSTM WATCH THRU 5 PM...FOR HAIL. NO DAMAGING WINDS EXPECTED./VII/ && .PREV DISCUSSION... /ISSUED 949 AM CDT MON APR 14 2014/ DISCUSSION... BOTH PREFRONTAL AND POSTFRONTAL CONVECTION INCREASING ACROSS AREA...WITH STG COLD FRONT BISECTING THE REGION. EXPECT INCREASING TSTM ACTIVITY ALONG COLD FRONT TO POSSIBLY PRODUCE SMALL HAIL. THIS FRONT WILL MOVE ACROSS SOUTHERN CWA BY MIDDAY. SMALL SHOWERS ALSO INCREASING IN COVERAGE ACROSS EXTREME NORTHERN CWA...SO RAISED POPS BACK UP INTO CHANCE CATEGORY./VII/ PREV DISCUSSION... /ISSUED 705 AM CDT MON APR 14 2014/ AVIATION... 12Z SFC ANALYSIS HAS THE COLD FRONT THROUGH THE TYR...TXK TERMINALS AND ALMOST ON TOP OF THE GGG TERMINAL. THE FRONT CONTINUES TO MAKE SLOW BUT STEADY PROGRESS TO THE SOUTH AND EAST THIS MORNING. AHEAD OF THE FRONT...REMNANT OUTFLOW BOUNDARY EXISTS FROM NEAR LFK TO MLU AND THIS FEATURE CONTINUES TO MOVE SLOWLY SOUTH AND EAST AS WELL. NEW STRONG TO SEVERE CONVECTION IS DEVELOPING JUST AHEAD OF THE FRONT BUT BEHIND THE OUTFLOW BOUNDARY ACROSS PORTIONS OF EAST CENTRAL TEXAS ATTM. CEILINGS DIRECTLY BEHIND THE FRONT GO TO BRIEF IFR CONDITIONS BUT THEN BECOME MVFR WHILE CEILINGS AHEAD OF THE FRONT ARE MOSTLY MVFR. FOR THE TERMINAL PACKAGE TODAY...PREVAILED MVFR CEILINGS THROUGH MUCH OF THE DAY WITH VCSH AND/OR VCTS MENTION. LATEST HRRR DATA SUGGEST THE POTENTIAL FOR POST FRONTAL SHOWERS TO MADE MENTION OF THIS AS WELL. STRONG PRESSURE GRADIENT IN THE WAKE OF THE FRONTAL BOUNDARY AND THUS...EXPECT SUSTAINED POST FRONTAL WINDS OF 14-18KTS WITH GUSTS APPROACHING 30KTS. WINDS WILL DECOUPLE LATE THIS EVENING AND EXPECTING CLEARING FROM WEST TO EAST OVERNIGHT AS WELL. /13/ PREV DISCUSSION... /ISSUED 552 AM CDT MON APR 14 2014/ DISCUSSION... A BUSY MORNING TO SAY THE LEAST WITH VARIOUS ELEMENTS TO CONTEND WITH AS IT RELATES TO WWA CRITERIA SO APOLOGIZE FOR THE BELATED DISCUSSION. FIRST THINGS FIRST...ALL CONVECTIVE WATCHES HAVE EITHER EXPIRED OR BEEN DROPPED FOR OUR REGION AS WIDESPREAD SEVERE THREAT NEVER REALLY MATERIALIZED AS INITIALLY ANTICIPATED DUE PRIMARILY TO THE LACK OF INSTABILITY BUT ALSO SIGNIFICANT DRY SLOTTING WHICH WAS NOT EXACTLY FORESEEN. ALL THIS TO SAY THAT ALTHOUGH A SIGNIFICANT SEVERE EVENT DID NOT MATERIALIZE...A FEW ISOLD SEVERE STORMS DID PRODUCE SOME DAMAGING WIND GUSTS OVER EXTREME SW ARKANSAS AND ONE POSSIBLE TORNADO OVER NE TX LATE SUNDAY. NOW SHIFTING GEARS TO THE ACTUAL COLD FRONT AND POST-FRONTAL CONDITIONS...THE FRONT ITSELF WAS LOCATED ALONG A PBF...TXK...CRS LINE AS OF 10Z THIS MORNING GENERALLY SPLITTING OUR CWA IN HALF. CONVECTION CONTINUES OUT AHEAD OF THE FRONT WITH MAINLY LIGHT TO MODERATE SHWRS AND A FEW EMBEDDED TSTMS EXTENDING FROM S CNTRL AR BACK OVER MUCH OF N LA AND LOWER E TX. BEHIND THE FRONT...GUSTY NW WINDS AND SHARPLY COOLER TEMPERATURES ARE FOUND OVER SE OK AND EXTREME NE TX. THE VERY TIGHT PRESSURE GRADIENT HAS PROMPTED A LAKE WIND ADVISORY AREA WIDE FOR TODAY...ALBEIT STARTING A BIT LATER ACROSS OUR SERN HALF AS CONDITIONS WILL NOT BE MET OVER THESE AREAS UNTIL AROUND MIDDAY AND PERSISTING THROUGH MIDNIGHT. THE NEXT DILEMMA IS DETERMINING HOW FAR TEMPERATURES WILL FALL LATER TONIGHT INTO TUESDAY MORNING AND IF WE SEE NEAR FREEZING OR EVEN SUB-FREEZING READINGS...HOW FAR SOUTH WILL THEY MAKE IT. THE BEST HACK FOR NOW IS SE OK...ALL OF OUR NRN TIER AR COUNTIES AND POSSIBLY RED RIVER COUNTY IN NE TX. HAVE GONE AHEAD AND ISSUED A FREEZE WARNING FOR THESE AREAS TO BEGIN AFTER MIDNIGHT AND LASTING THROUGH LATE MORNING ON TUESDAY. ALTHOUGH THE DURATION SEEMS A BIT LONGER THAN WHAT MAY ACTUALLY OCCUR...WANTED TO MAKE SURE WE ARE COVERED ON EITHER SIDE IN CASE THE AIR MASS IS EVEN COLDER THAN CURRENTLY FORECAST. A FEW OTHER NOTES WORTH MENTIONING INCLUDE WIND CHILLS IN THE 20S AND 30S OVERNIGHT INTO TUESDAY MORNING EVEN WITH THE WINDS DECREASING SLIGHTLY AFTER MIDNIGHT. THE THREAT OF FREEZING TEMPERATURES OVER THESE SAME AREAS WILL BE POSSIBLE ONCE AGAIN ON WEDNESDAY MORNING AND MAYBE A FEW LOCATIONS FARTHER SOUTH IN SRN AR/NRN LA SO WILL NEED TO MONITOR FOR ADDITIONAL FREEZE WARNINGS. TEMPERATURES WILL GRADUALLY MODERATE THROUGH THE REMAINDER OF THE WEEK AND GENERALLY RUN NEAR SEASONAL AVERAGES WITH ANOTHER CHANCE OF SHWRS AND TSTMS RETURNING LATE THURSDAY INTO FRIDAY WITH THE ARRIVAL OF OUR NEXT COLD FRONT. THE WEEKEND LOOKS MIXED WITH A BRIEF BREAK FROM THE RAIN EARLY SATURDAY BUT THEN RETURNING BY LATE SATURDAY AND ESPECIALLY SUNDAY WITH AN UPPER LEVEL DISTURBANCE SHIFTING ACROSS THE REGION FROM THE SW TX. /19/ && .PRELIMINARY POINT TEMPS/POPS... SHV 67 36 60 36 68 / 40 20 0 0 0 MLU 70 36 60 33 67 / 40 40 0 0 0 DEQ 55 30 60 32 66 / 30 10 0 0 0 TXK 58 34 60 36 66 / 30 10 0 0 0 ELD 65 33 60 32 66 / 40 30 0 0 0 TYR 58 34 61 36 68 / 40 10 0 0 0 GGG 62 34 61 34 68 / 40 10 0 0 0 LFK 70 36 63 34 69 / 50 20 0 0 0 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...LAKE WIND ADVISORY UNTIL MIDNIGHT CDT TONIGHT FOR THE FOLLOWING ZONES: ARZ060-061-071>073. LAKE WIND ADVISORY UNTIL MIDNIGHT CDT TONIGHT FOR THE FOLLOWING ZONES: ARZ050-051-059-070. FREEZE WARNING FROM 1 AM TO 9 AM CDT TUESDAY FOR THE FOLLOWING ZONES: ARZ050-051-059>061. LA...LAKE WIND ADVISORY UNTIL MIDNIGHT CDT TONIGHT FOR THE FOLLOWING ZONES: LAZ001>006-010>014-017>022. OK...LAKE WIND ADVISORY UNTIL MIDNIGHT CDT TONIGHT FOR THE FOLLOWING ZONES: OKZ077. FREEZE WARNING FROM 1 AM TO 9 AM CDT TUESDAY FOR THE FOLLOWING ZONES: OKZ077. TX...LAKE WIND ADVISORY UNTIL MIDNIGHT CDT TONIGHT FOR THE FOLLOWING ZONES: TXZ152-153-165>167. LAKE WIND ADVISORY UNTIL MIDNIGHT CDT TONIGHT FOR THE FOLLOWING ZONES: TXZ096-097-108>112-124>126-136>138-149>151. FREEZE WARNING FROM 1 AM TO 9 AM CDT TUESDAY FOR THE FOLLOWING ZONES: TXZ096. && $$ VII
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
949 AM CDT MON APR 14 2014 .DISCUSSION... BOTH PREFRONTAL AND POSTFRONTAL CONVECTION INCREASING ACROSS AREA...WITH STG COLD FRONT BISECTING THE REGION. EXPECT INCREASING TSTM ACTIVITY ALONG COLD FRONT TO POSSIBLY PRODUCE SMALL HAIL. THIS FRONT WILL MOVE ACROSS SOUTHERN CWA BY MIDDAY. SMALL SHOWERS ALSO INCREASING IN COVERAGE ACROSS EXTREME NORTHERN CWA...SO RAISED POPS BACK UP INTO CHANCE CATEGORY./VII/ && .PREV DISCUSSION... /ISSUED 705 AM CDT MON APR 14 2014/ AVIATION... 12Z SFC ANALYSIS HAS THE COLD FRONT THROUGH THE TYR...TXK TERMINALS AND ALMOST ON TOP OF THE GGG TERMINAL. THE FRONT CONTINUES TO MAKE SLOW BUT STEADY PROGRESS TO THE SOUTH AND EAST THIS MORNING. AHEAD OF THE FRONT...REMNANT OUTFLOW BOUNDARY EXISTS FROM NEAR LFK TO MLU AND THIS FEATURE CONTINUES TO MOVE SLOWLY SOUTH AND EAST AS WELL. NEW STRONG TO SEVERE CONVECTION IS DEVELOPING JUST AHEAD OF THE FRONT BUT BEHIND THE OUTFLOW BOUNDARY ACROSS PORTIONS OF EAST CENTRAL TEXAS ATTM. CEILINGS DIRECTLY BEHIND THE FRONT GO TO BRIEF IFR CONDITIONS BUT THEN BECOME MVFR WHILE CEILINGS AHEAD OF THE FRONT ARE MOSTLY MVFR. FOR THE TERMINAL PACKAGE TODAY...PREVAILED MVFR CEILINGS THROUGH MUCH OF THE DAY WITH VCSH AND/OR VCTS MENTION. LATEST HRRR DATA SUGGEST THE POTENTIAL FOR POST FRONTAL SHOWERS TO MADE MENTION OF THIS AS WELL. STRONG PRESSURE GRADIENT IN THE WAKE OF THE FRONTAL BOUNDARY AND THUS...EXPECT SUSTAINED POST FRONTAL WINDS OF 14-18KTS WITH GUSTS APPROACHING 30KTS. WINDS WILL DECOUPLE LATE THIS EVENING AND EXPECTING CLEARING FROM WEST TO EAST OVERNIGHT AS WELL. /13/ PREV DISCUSSION... /ISSUED 552 AM CDT MON APR 14 2014/ DISCUSSION... A BUSY MORNING TO SAY THE LEAST WITH VARIOUS ELEMENTS TO CONTEND WITH AS IT RELATES TO WWA CRITERIA SO APOLOGIZE FOR THE BELATED DISCUSSION. FIRST THINGS FIRST...ALL CONVECTIVE WATCHES HAVE EITHER EXPIRED OR BEEN DROPPED FOR OUR REGION AS WIDESPREAD SEVERE THREAT NEVER REALLY MATERIALIZED AS INITIALLY ANTICIPATED DUE PRIMARILY TO THE LACK OF INSTABILITY BUT ALSO SIGNIFICANT DRY SLOTTING WHICH WAS NOT EXACTLY FORESEEN. ALL THIS TO SAY THAT ALTHOUGH A SIGNIFICANT SEVERE EVENT DID NOT MATERIALIZE...A FEW ISOLD SEVERE STORMS DID PRODUCE SOME DAMAGING WIND GUSTS OVER EXTREME SW ARKANSAS AND ONE POSSIBLE TORNADO OVER NE TX LATE SUNDAY. NOW SHIFTING GEARS TO THE ACTUAL COLD FRONT AND POST-FRONTAL CONDITIONS...THE FRONT ITSELF WAS LOCATED ALONG A PBF...TXK...CRS LINE AS OF 10Z THIS MORNING GENERALLY SPLITTING OUR CWA IN HALF. CONVECTION CONTINUES OUT AHEAD OF THE FRONT WITH MAINLY LIGHT TO MODERATE SHWRS AND A FEW EMBEDDED TSTMS EXTENDING FROM S CNTRL AR BACK OVER MUCH OF N LA AND LOWER E TX. BEHIND THE FRONT...GUSTY NW WINDS AND SHARPLY COOLER TEMPERATURES ARE FOUND OVER SE OK AND EXTREME NE TX. THE VERY TIGHT PRESSURE GRADIENT HAS PROMPTED A LAKE WIND ADVISORY AREA WIDE FOR TODAY...ALBEIT STARTING A BIT LATER ACROSS OUR SERN HALF AS CONDITIONS WILL NOT BE MET OVER THESE AREAS UNTIL AROUND MIDDAY AND PERSISTING THROUGH MIDNIGHT. THE NEXT DILEMMA IS DETERMINING HOW FAR TEMPERATURES WILL FALL LATER TONIGHT INTO TUESDAY MORNING AND IF WE SEE NEAR FREEZING OR EVEN SUB-FREEZING READINGS...HOW FAR SOUTH WILL THEY MAKE IT. THE BEST HACK FOR NOW IS SE OK...ALL OF OUR NRN TIER AR COUNTIES AND POSSIBLY RED RIVER COUNTY IN NE TX. HAVE GONE AHEAD AND ISSUED A FREEZE WARNING FOR THESE AREAS TO BEGIN AFTER MIDNIGHT AND LASTING THROUGH LATE MORNING ON TUESDAY. ALTHOUGH THE DURATION SEEMS A BIT LONGER THAN WHAT MAY ACTUALLY OCCUR...WANTED TO MAKE SURE WE ARE COVERED ON EITHER SIDE IN CASE THE AIR MASS IS EVEN COLDER THAN CURRENTLY FORECAST. A FEW OTHER NOTES WORTH MENTIONING INCLUDE WIND CHILLS IN THE 20S AND 30S OVERNIGHT INTO TUESDAY MORNING EVEN WITH THE WINDS DECREASING SLIGHTLY AFTER MIDNIGHT. THE THREAT OF FREEZING TEMPERATURES OVER THESE SAME AREAS WILL BE POSSIBLE ONCE AGAIN ON WEDNESDAY MORNING AND MAYBE A FEW LOCATIONS FARTHER SOUTH IN SRN AR/NRN LA SO WILL NEED TO MONITOR FOR ADDITIONAL FREEZE WARNINGS. TEMPERATURES WILL GRADUALLY MODERATE THROUGH THE REMAINDER OF THE WEEK AND GENERALLY RUN NEAR SEASONAL AVERAGES WITH ANOTHER CHANCE OF SHWRS AND TSTMS RETURNING LATE THURSDAY INTO FRIDAY WITH THE ARRIVAL OF OUR NEXT COLD FRONT. THE WEEKEND LOOKS MIXED WITH A BRIEF BREAK FROM THE RAIN EARLY SATURDAY BUT THEN RETURNING BY LATE SATURDAY AND ESPECIALLY SUNDAY WITH AN UPPER LEVEL DISTURBANCE SHIFTING ACROSS THE REGION FROM THE SW TX. /19/ && .PRELIMINARY POINT TEMPS/POPS... SHV 67 36 60 36 68 / 40 20 0 0 0 MLU 70 36 60 33 67 / 60 40 0 0 0 DEQ 55 30 60 32 66 / 30 10 0 0 0 TXK 58 34 60 36 66 / 30 10 0 0 0 ELD 65 33 60 32 66 / 40 30 0 0 0 TYR 58 34 61 36 68 / 40 10 0 0 0 GGG 62 34 61 34 68 / 40 10 0 0 0 LFK 70 36 63 34 69 / 50 20 0 0 0 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...LAKE WIND ADVISORY UNTIL MIDNIGHT CDT TONIGHT FOR THE FOLLOWING ZONES: ARZ060-061-071>073. LAKE WIND ADVISORY UNTIL MIDNIGHT CDT TONIGHT FOR THE FOLLOWING ZONES: ARZ050-051-059-070. FREEZE WARNING FROM 1 AM TO 9 AM CDT TUESDAY FOR THE FOLLOWING ZONES: ARZ050-051-059>061. LA...LAKE WIND ADVISORY UNTIL MIDNIGHT CDT TONIGHT FOR THE FOLLOWING ZONES: LAZ001>006-010>014-017>022. OK...LAKE WIND ADVISORY UNTIL MIDNIGHT CDT TONIGHT FOR THE FOLLOWING ZONES: OKZ077. FREEZE WARNING FROM 1 AM TO 9 AM CDT TUESDAY FOR THE FOLLOWING ZONES: OKZ077. TX...LAKE WIND ADVISORY UNTIL MIDNIGHT CDT TONIGHT FOR THE FOLLOWING ZONES: TXZ152-153-165>167. LAKE WIND ADVISORY UNTIL MIDNIGHT CDT TONIGHT FOR THE FOLLOWING ZONES: TXZ096-097-108>112-124>126-136>138-149>151. FREEZE WARNING FROM 1 AM TO 9 AM CDT TUESDAY FOR THE FOLLOWING ZONES: TXZ096. && $$
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
705 AM CDT MON APR 14 2014 .AVIATION... 12Z SFC ANALYSIS HAS THE COLD FRONT THROUGH THE TYR...TXK TERMINALS AND ALMOST ON TOP OF THE GGG TERMINAL. THE FRONT CONTINUES TO MAKE SLOW BUT STEADY PROGRESS TO THE SOUTH AND EAST THIS MORNING. AHEAD OF THE FRONT...REMNANT OUTFLOW BOUNDARY EXISTS FROM NEAR LFK TO MLU AND THIS FEATURE CONTINUES TO MOVE SLOWLY SOUTH AND EAST AS WELL. NEW STRONG TO SEVERE CONVECTION IS DEVELOPING JUST AHEAD OF THE FRONT BUT BEHIND THE OUTFLOW BOUNDARY ACROSS PORTIONS OF EAST CENTRAL TEXAS ATTM. CEILINGS DIRECTLY BEHIND THE FRONT GO TO BRIEF IFR CONDITIONS BUT THEN BECOME MVFR WHILE CEILINGS AHEAD OF THE FRONT ARE MOSTLY MVFR. FOR THE TERMINAL PACKAGE TODAY...PREVAILED MVFR CEILINGS THROUGH MUCH OF THE DAY WITH VCSH AND/OR VCTS MENTION. LATEST HRRR DATA SUGGEST THE POTENTIAL FOR POST FRONTAL SHOWERS TO MADE MENTION OF THIS AS WELL. STRONG PRESSURE GRADIENT IN THE WAKE OF THE FRONTAL BOUNDARY AND THUS...EXPECT SUSTAINED POST FRONTAL WINDS OF 14-18KTS WITH GUSTS APPROACHING 30KTS. WINDS WILL DECOUPLE LATE THIS EVENING AND EXPECTING CLEARING FROM WEST TO EAST OVERNIGHT AS WELL. /13/ && .PREV DISCUSSION... /ISSUED 552 AM CDT MON APR 14 2014/ DISCUSSION... A BUSY MORNING TO SAY THE LEAST WITH VARIOUS ELEMENTS TO CONTEND WITH AS IT RELATES TO WWA CRITERIA SO APOLOGIZE FOR THE BELATED DISCUSSION. FIRST THINGS FIRST...ALL CONVECTIVE WATCHES HAVE EITHER EXPIRED OR BEEN DROPPED FOR OUR REGION AS WIDESPREAD SEVERE THREAT NEVER REALLY MATERIALIZED AS INITIALLY ANTICIPATED DUE PRIMARILY TO THE LACK OF INSTABILITY BUT ALSO SIGNIFICANT DRY SLOTTING WHICH WAS NOT EXACTLY FORESEEN. ALL THIS TO SAY THAT ALTHOUGH A SIGNIFICANT SEVERE EVENT DID NOT MATERIALIZE...A FEW ISOLD SEVERE STORMS DID PRODUCE SOME DAMAGING WIND GUSTS OVER EXTREME SW ARKANSAS AND ONE POSSIBLE TORNADO OVER NE TX LATE SUNDAY. NOW SHIFTING GEARS TO THE ACTUAL COLD FRONT AND POST-FRONTAL CONDITIONS...THE FRONT ITSELF WAS LOCATED ALONG A PBF...TXK...CRS LINE AS OF 10Z THIS MORNING GENERALLY SPLITTING OUR CWA IN HALF. CONVECTION CONTINUES OUT AHEAD OF THE FRONT WITH MAINLY LIGHT TO MODERATE SHWRS AND A FEW EMBEDDED TSTMS EXTENDING FROM S CNTRL AR BACK OVER MUCH OF N LA AND LOWER E TX. BEHIND THE FRONT...GUSTY NW WINDS AND SHARPLY COOLER TEMPERATURES ARE FOUND OVER SE OK AND EXTREME NE TX. THE VERY TIGHT PRESSURE GRADIENT HAS PROMPTED A LAKE WIND ADVISORY AREA WIDE FOR TODAY...ALBEIT STARTING A BIT LATER ACROSS OUR SERN HALF AS CONDITIONS WILL NOT BE MET OVER THESE AREAS UNTIL AROUND MIDDAY AND PERSISTING THROUGH MIDNIGHT. THE NEXT DILEMMA IS DETERMINING HOW FAR TEMPERATURES WILL FALL LATER TONIGHT INTO TUESDAY MORNING AND IF WE SEE NEAR FREEZING OR EVEN SUB-FREEZING READINGS...HOW FAR SOUTH WILL THEY MAKE IT. THE BEST HACK FOR NOW IS SE OK...ALL OF OUR NRN TIER AR COUNTIES AND POSSIBLY RED RIVER COUNTY IN NE TX. HAVE GONE AHEAD AND ISSUED A FREEZE WARNING FOR THESE AREAS TO BEGIN AFTER MIDNIGHT AND LASTING THROUGH LATE MORNING ON TUESDAY. ALTHOUGH THE DURATION SEEMS A BIT LONGER THAN WHAT MAY ACTUALLY OCCUR...WANTED TO MAKE SURE WE ARE COVERED ON EITHER SIDE IN CASE THE AIR MASS IS EVEN COLDER THAN CURRENTLY FORECAST. A FEW OTHER NOTES WORTH MENTIONING INCLUDE WIND CHILLS IN THE 20S AND 30S OVERNIGHT INTO TUESDAY MORNING EVEN WITH THE WINDS DECREASING SLIGHTLY AFTER MIDNIGHT. THE THREAT OF FREEZING TEMPERATURES OVER THESE SAME AREAS WILL BE POSSIBLE ONCE AGAIN ON WEDNESDAY MORNING AND MAYBE A FEW LOCATIONS FARTHER SOUTH IN SRN AR/NRN LA SO WILL NEED TO MONITOR FOR ADDITIONAL FREEZE WARNINGS. TEMPERATURES WILL GRADUALLY MODERATE THROUGH THE REMAINDER OF THE WEEK AND GENERALLY RUN NEAR SEASONAL AVERAGES WITH ANOTHER CHANCE OF SHWRS AND TSTMS RETURNING LATE THURSDAY INTO FRIDAY WITH THE ARRIVAL OF OUR NEXT COLD FRONT. THE WEEKEND LOOKS MIXED WITH A BRIEF BREAK FROM THE RAIN EARLY SATURDAY BUT THEN RETURNING BY LATE SATURDAY AND ESPECIALLY SUNDAY WITH AN UPPER LEVEL DISTURBANCE SHIFTING ACROSS THE REGION FROM THE SW TX. /19/ && .PRELIMINARY POINT TEMPS/POPS... SHV 67 36 60 36 68 / 60 20 0 0 0 MLU 70 36 60 33 67 / 70 40 0 0 0 DEQ 55 30 60 32 66 / 30 10 0 0 0 TXK 58 34 60 36 66 / 30 10 0 0 0 ELD 65 33 60 32 66 / 60 30 0 0 0 TYR 58 34 61 36 68 / 30 10 0 0 0 GGG 62 34 61 34 68 / 30 10 0 0 0 LFK 70 36 63 34 69 / 60 20 0 0 0 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...LAKE WIND ADVISORY FROM NOON TODAY TO MIDNIGHT CDT TONIGHT FOR THE FOLLOWING ZONES: ARZ060-061-071>073. LAKE WIND ADVISORY UNTIL MIDNIGHT CDT TONIGHT FOR THE FOLLOWING ZONES: ARZ050-051-059-070. FREEZE WARNING FROM 1 AM TO 9 AM CDT TUESDAY FOR THE FOLLOWING ZONES: ARZ050-051-059>061. LA...LAKE WIND ADVISORY FROM NOON TODAY TO MIDNIGHT CDT TONIGHT FOR THE FOLLOWING ZONES: LAZ001>006-010>014-017>022. OK...LAKE WIND ADVISORY UNTIL MIDNIGHT CDT TONIGHT FOR THE FOLLOWING ZONES: OKZ077. FREEZE WARNING FROM 1 AM TO 9 AM CDT TUESDAY FOR THE FOLLOWING ZONES: OKZ077. TX...LAKE WIND ADVISORY FROM NOON TODAY TO MIDNIGHT CDT TONIGHT FOR THE FOLLOWING ZONES: TXZ152-153-165>167. LAKE WIND ADVISORY UNTIL MIDNIGHT CDT TONIGHT FOR THE FOLLOWING ZONES: TXZ096-097-108>112-124>126-136>138-149>151. FREEZE WARNING FROM 1 AM TO 9 AM CDT TUESDAY FOR THE FOLLOWING ZONES: TXZ096. && $$ 13
AREA FORECAST DISCUSSION
NWS CARIBOU ME
622 PM EDT MON APR 14 2014 .SYNOPSIS... A WARM FRONT WILL LIFT WELL NORTH OF THE AREA TONIGHT. A STRONG COLD FRONT WILL APPROACH LATER TUESDAY THEN CROSS THE REGION TUESDAY NIGHT. && .NEAR TERM /THROUGH TUESDAY/... 600 PM UPDATE: MODELS ARE IN DISAGREEMENT WITH REGARD TO HOW FAR E A BAND OF PRE-COLD FRONTAL SHWRS REACH INTO OUR FA LATER TNGT. OF THE MODELS...THE 18Z GFS IS THE MOST AGGRESSIVE...BRINGING QPF VALUES OF 0.10-0.25 AS FAR E AS W CNTRL TO NE PTNS OF THE FA. OTHER MODELS SUCH AS THE 12Z ECMWF HARDLY BRINGS ANY RNFL EVEN INTO THE NW PTN OF THE FA. A COMPROMISE BETWEEN THESE TWO SCENARIOS AS SUGGESTED BY THE LATEST HRLY HRRR MODEL SIMULATED FCST RADAR REF SUGGESTS BRINGING UPWARDS OF ARND A TENTH OF AN INCH TO NW PTNS OF THE FA AND LESSER AMOUNTS ELSEWHERE...RESULTING IN INCREASING POPS TO LIKELY CAT OVR THE NW LATER TNGT AND KEEPING CHC OR LOWER POPS ELSEWHERE. REGARDING FOG POTENTIAL...BASED ON INITIAL NO IMMEDIATE SIGNS OF FOG...WE DELAYED THE ONSET TIL 10 PM OVR DOWNEAST AREAS TIL PROGRESSIVELY AS LATE AS 2 AM OVR THE NW AND FAR NE...THINKING THAT SATURATION OF THE LLVL AIR MASS WILL WORK NW FROM THE COAST...BUT WE ARE NOT VERY CONFIDENT OF THIS TMG WITH IT POSSIBLE THAT FOG COULD BREAK OUT SIMULTANEOUSLY OVR RELATIVELY LARGE PTNS OF THE FA ANYTIME AFT 9 PM. LASTLY...WE UPDATED FCST HRLY TEMPS TO UNCHGD FCST OVRNGT LOWS POSTED AT 6 AM FROM 5 PM OBSVD TEMPS. ORGNL DISC: MAIN FOCUS REMAINS ON THE POTENTIAL FOR FLOODING FROM ICE JAMS/RISING RIVER LEVELS AND THIS ADDRESSED IN MORE DETAIL IN THE HYDRO SECTION BLO... AS OF MID AFTN...MOST ALL OF THE FA NOW INTO THE WARM AIR XCPT FOR FAR N AND NERN AREAS WHERE THE COLD AIR HAS BEEN SLOW TO ROOT OUT... TEMPS GENERALLY IN THE MID 50S TO MID 60S W/ MID 40S STILL AT KFVE. AFTN MIXING HAS ALLOWED THE FOG/STRATUS FROM THIS AM TO BURN OFF BUT W/ PLENTY OF LOW-LEVEL MOISTURE FROM ALL THE SNOW MELT AND A VRY COLD GROUND SFC SHOULD ALLOW FOG/STRATUS TO REDEVELOP THIS EVE W/ THE LOSS OF HEATING AND MIXING. UNSEASONABLY MILD AIR WILL PERSIST ACROSS THE REGION TNGT THRU TUE AS A SLOW MOVG COLD FRONT NOW CROSSING THE ERN GRT LAKES APPROACHES OUR AREA LATER TUE. EXPECT TEMPS TO ONLY DROP INTO THE UPPER 40S TO 50S MOST AREAS WILL KEEP AN ACCELERATED SNOW MELT IN PLACE. IN ADDITION TO THE MILD TEMPS AND RAPID SNOW MELT...A SIGNIFICANT RAIN EVENT IS STILL ON TAP AS A PD OF MDT TO LOCALLY HVY RAIN IN ADVANCE OF THIS FRONT OVERSPREADS OUR REGION FROM W-E ON TUE AND CONTS INTO TUE NGT. && .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/... HE COLD FRONT WILL BE APPROACHING THE MAINE/QUEBEC BORDER EARLY TUESDAY EVENING. THE FRONT WILL BE PRECEDED AND ACCOMPANIED BY WIDESPREAD STEADY RAINFALL TUESDAY NIGHT AS THE FRONT CROSSES THE REGION FROM THE WEST. TEMPERATURES ARE EXPECTED TO REMAIN ABOVE FREEZING MOST OF TUESDAY EVENING. THE COMBINATION OF THE RAINFALL AND ABOVE FREEZING TEMPERATURES WILL RESULT IN CONTINUED SNOW MELT/RUNOFF RESULTING IN RIVER RISES AND ICE MOVEMENT. SEE THE HYDROLOGY SECTION BELOW FOR MORE DETAILED INFORMATION. COLDER AIR FILTERING IN BEHIND THE COLD FRONT WILL RESULT IN THE POSSIBILITY OF LINGERING RAIN CHANGING TO SNOW SHOWERS LATER TUESDAY NIGHT AND EARLY WEDNESDAY MORNING ACROSS NORTHERN AREAS BEFORE THE PRECIPITATION ENDS. LITTLE IF ANY SNOW ACCUMULATION IS EXPECTED. A LARGE RIDGE OF HIGH PRESSURE WILL BUILD EAST TOWARD THE REGION DURING WEDNESDAY AFTERNOON WITH CLEARING SKIES EXPECTED. HIGHS ON WEDNESDAY WILL BE BELOW NORMAL LEVELS WITH HIGHS ON WEDNESDAY IN THE LOW TO MID 30S NORTH AND UPPER 30S TO LOWER 40S ACROSS CENTRAL AND DOWNEAST AREAS. HIGH PRESSURE WILL SETTLE ACROSS THE AREA WEDNESDAY NIGHT WITH CLEAR SKIES AND LIGHT WINDS. LOWS WEDNESDAY NIGHT WILL RANGE FROM THE MID TO UPPER TEENS NORTH AND LOW TO MID 20S CENTRAL AND DOWNEAST. HIGH PRESSURE WILL MOVE EAST THURSDAY MOSTLY SUNNY SKIES EXPECTED. HIGHS WILL BE CLOSE TO NORMAL FOR THIS TIME OF YEAR. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... THE PERIOD WILL BEGIN WITH MAINE UNDER THE INFLUENCE OF A SURFACE HIGH PRESSURE. THIS HIGH PRESSURE WILL SLIDE EAST THROUGH THE AREA THURSDAY NIGHT. A WEAK SHORTWAVE WILL BRING SOME CLOUDS ACROSS THE NORTH THURSDAY NIGHT INTO FRIDAY. CLOUDS WILL BEGIN TO FILL IN ACROSS THE AREA MORE AS WE GO INTO FRIDAY NIGHT AHEAD OF APPROACHING DISTURBANCE. THERE IS SOME CONTINUED MODEL DISAGREEMENT WITH EVOLUTION OF THIS NEXT SYSTEM. RIGHT NOW THE GFS BRINGS A SHORTWAVE AND SURFACE LOW ACROSS THE REGION SATURDAY NIGHT INTO EARLY SUNDAY. WHILE THE ECMWF WANTS TO BRING THE SHORTWAVE ACROSS THE REGION BUT KEEPS THE SURFACE LOW MOSTLY SOUTH OFF THE COAST OF MAINE. SINCE THERE IS STILL SOME DISAGREEMENT WITH THIS WILL STICK WITH THE BLEND APPROACH WITH NO MAJOR ADJUSTMENTS DURING THIS PERIOD. THIS DISTURBANCE SLIDES EAST AND ANOTHER AREA OF HIGH PRESSURE PROGRESSES EAST FOR MONDAY. TEMPERATURES THROUGH THE PERIOD WILL BE NEAR TO SLIGHTLY ABOVE NORMAL. && .AVIATION /22Z MONDAY THROUGH SATURDAY/... NEAR TERM: STRATUS/FOG HAS BURNED OFF ALL BUT KFVE AS VERY WARM AIR HAS OVERSPREAD THE FA AND ALLOWED THE LOWER LEVEL MOISTURE TO MIX OUT. MELTING SNOW WILL LEAVE ABUNDANT LOW-LEVEL MOISTURE IN PLACE AND W/ A VRY COLD SFC...FOG/STRATUS LIKELY TO REDEVELOP THIS EVE AFTER THE LOSS OF HEATING AND PERSIST INTO AT LEAST TUE AM. THUS...EXPECT VFR CONDS THIS AFTN AND ERLY EVE TO GIVE WAY TO LIFR AGAIN ALL TAF SITES BY LATE EVE W/ THESE CONDS CONTG TUE. A SLOW MOVG COLD FRONT APPROACHING FROM THE W WILL LIKELY HELP KEEP PRIMARILY IFR CONDS ACROSS THE AREA THRU TUE... SHORT TERM: IFR CONDITIONS ARE EXPECTED TUESDAY NIGHT. SOME EARLY MORNING IFR/MVFR IS POSSIBLE ACROSS EASTERN TERMINALS OTHERWISE VFR IS EXPECTED BY WEDNESDAY AFTERNOON. VFR IS THEN EXPECTED THROUGH THURSDAY. && .MARINE... NEAR TERM: HAVE DROPPED THE GLW WATCH IN FAVOR OF A GLW WRNG FROM 12Z TUE THRU 08Z WED... BRISK SRLY WNDS AHEAD OF A SLOW MOVG COLD FRONT WILL AFFECT THE WATERS UNTIL A STRONG COLD FRONT CROSSES THE WATERS ERLY WED AM... SHORT TERM: A GALE WARNING WILL BE IN EFFECT THROUGH TUESDAY NIGHT. WINDS/SEAS WILL THEN DIMINISH TO SMALL CRAFT ADVISORY CONDITIONS. WINDS WILL THEN DIMINISH LATER WEDNESDAY AS THE HIGH BUILDS EAST HOWEVER SEAS MAY REMAIN AT SMALL CRAFT ADVISORY LEVELS INTO EARLY THURSDAY. && .HYDROLOGY... THE FLOOD WATCH REMAINS IN EFFECT THRU WED... UNSEASONABLY WARM AIR CONTS TO SPREAD ACROSS THE AREA W/ TEMPS NOW INTO THE 60S ALL BUT FAR N AND NERN AREAS AND ALONG THE IMMEDIATE COAST. W/ THE WARM AIR HAVING JUST ARRIVED THIS AFTN...WILL BE A BIT OF A LAG BEFORE RIVERS/STREAMS BEGIN TO RESPOND TO THE INCREASED SNOW MELT. RIVER GAGES CONT TO SHOW SLOW RISES BUT THIS SHOULD INCREASE OVER THE NXT 6-12 HRS AND APPEARS WE ARE ABOUT TO ENTER INTO THE MAIN THREAT WINDOW FOR SIGNIFICANT FLOODING POTENTIAL ACROSS OUR REGION. TO FURTHER EXTENUATE CONCERNS...TEMPS WILL REMAIN WELL ABV FREEZING TNGT THRU TUE ALLOWING FOR CONTD ACCELERATED SNOW MELT AND MODERATE TO HEAVY RAIN WILL OCCUR ACROSS THE REGION LATER TUESDAY INTO TUESDAY NIGHT IN ADVANCE OF THE SLOW MOVING COLD FRONT. THE THREAT OF ICE JAM FLOODING WILL CONT TO INCREASE FROM NOW THRU TUE WITH STILL RISING RIVER LEVELS. THE THREAT OF ICE JAM FLOODING WILL THEN PERSIST TUESDAY NIGHT THROUGH WEDNESDAY WHILE RIVER LEVELS CONTINUE TO RISE AND ICE MOVEMENT CONTINUES. FINALLY...THE RAPIDLY MELTING SNOW MAY ALSO CAUSE SOME FLOODING OF LOW LYING AREAS AND ROADWAYS. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...FLOOD WATCH THROUGH WEDNESDAY EVENING FOR MEZ001>006-010-011- 015>017-029>032. MARINE...GALE WARNING FROM 8 AM TUESDAY TO 4 AM EDT WEDNESDAY FOR ANZ050>052. && $$ NEAR TERM...VJN SHORT TERM...DUDA LONG TERM...JORDAN AVIATION...VJN/DUDA MARINE...VJN/DUDA HYDROLOGY...KHW
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
746 PM EDT TUE APR 15 2014 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 531 PM EDT TUE APR 15 2014 BIGGEST FORECAST CONCERNS FOR SHORT TERM FOCUS ON WINTER STORM HEADLINES STARTING WEDNESDAY AND CONTINUING INTO THURSDAY. WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH FROM HUDSON BAY THROUGH THE CENTRAL GREAT LAKES INTO THE GULF COAST STATES. INSTABILITY ASSOC WITH THIS TROUGH HAS SUPPORTED SOME DIURNAL -SHSN ACROSS INLAND AREAS THIS AFTERNOON. THE SHORTWAVE MOVING IN OFF THE PAC NW WILL BE THE FEATURE OF INTEREST IN THE SHORT TERM AS IT DEVELOPS A DEEPENING STORM SYSTEM OVER THE NRN PLAINS LATE TONIGHT AND BRINGS IT TOWARD THE WRN GREAT LAKES LATE WED INTO WED NIGHT. TONIGHT...ANY LEFTOVER DIURNAL SHSN OVER S CNTRL UPPER MI WILL DIMINISH EARLY THIS EVENING AS PARTLY CLOUDY SKIES AND LIGHT WINDS ALLOW TEMPS TO FALL INTO THE LOW SINGLE DIGITS OVER TYPICAL COLD SPOTS FAR EAST TO 15 TO 20F RANGE FOR DOWNSLOPING AREAS ALONG LAKE SUPERIOR FAR WEST AND AREAS CLOSE TO BAY OF GREEN BAY. TEMPS MAY CLIMB LATE AS CLOUDS INCREASE AHEAD OF THE APPROACHING LOW PRESSURE SYSTEM. WAA LIGHT SNOW WITH INCREASING 280K-290K ISENTROPIC LIFT IS EXPECTED TO REMAIN MAINLY WEST OF UPPER MI BUT MAY SLIDE INTO THE FAR WEST LATE. WEDNESDAY...MODELS GENERALLY IN AGREEMENT SHOWING SHORTWAVE OF INTEREST AND ASSOC DEEPENING SFC LOW OVER SE SOUTH DAKOTA AROUND 12Z THEN DIFFER ON HOW QUICKLY THEY LIFT THIS LOW ENE TOWARD THE UPPER GREAT LAKES. MOST OF 12Z MODELS GENERALLY TRENDING SLIGHTLY SLOWER AND FARTHER SE THAN 06Z RUNS WITH TRACK OF SFC LOW. MODELS INDICATE WARM AIR ADVECTION AND ISENTROPIC ASCENT ALONG AND AHEAD OF THE LOW AND INVERTED SFC TROUGH SHOULD SUPPORT EXPANDING SNOW SHIELD FM CNTRL MINNESOTA INTO NORTHWEST WI LATE TONIGHT THROUGH DAYBREAK ON WEDNESDAY. THIS SNOW SHIELD WILL THEN SPREAD INTO WEST AND CENTRAL UPPER MI DURING THE DAY ON WEDNESDAY. AS SFC TROUGH EDGES CLOSER TO UPR MICHIGAN WED AFTN ISENTROPIC ASCENT BECOMES MAXIMIZED ON 285-290K SFCS ACROSS UPR MICHIGAN FROM 15Z INTO WED EVENING. GFS REMAINS QUICKEST OF 12Z MODELS WHILE THE ECMWF IS THE SLOWEST. THE NAM AND REGIONAL GEM FALL SOMEWHERE BTWN THESE SOLNS. H7 MIXING RATIOS IN 2.5-3 G/KG RANGE SUGGESTS 12 HOUR SNOW AMOUNTS 4-6 INCHES OVER MAINLY THE WEST HALF COUNTIES. IT/S POSSIBLE ACTUAL SNOW AMOUNTS ON WED COULD BE HELD DOWN SOME AS SNOW ARRIVES DURING THE DAYTIME WHEN INSOLATION COULD LIMIT ACCUMS ESPECIALLY ON HIGHER TRAFFIC/TRAVELLED ROADS. CROSS SECTIONS SUGGEST POSSIBILITY OF HEAVIER BANDED SNOWFALL OVER WESTERN COUNTIES WITH NEG EPV ABOVE FAIRLY STRONG 7H FGEN FORCING SO THIS COULD ADD A FEW INCHES TO THE 4-6 INCH TOTALS RENDERED SOLELY FM ISENTROPIC ASCENT. WITH ALL ABOVE FACTORS TAKEN INTO CONSIDERATION...HAVE DECIDED TO UPGRADE WATCHES OVER THE WEST HALF COUNTIES TO WARNINGS FROM MQT-DICKINSON WESTWARD. GENERALLY STARTED WARNINGS ON WED FM 14Z SOUTH TO 16Z NORTH. ALSO MOVED THE AXIS OF HEAVIER PCPN/SNOWFALL SLIGHTLY FARTHER EASTWARD BASED ON 12Z MODEL TRENDS WITH SNOWFALL AMOUNTS ON WED RANGING FM 3 TO 5 INCHES OVER THE NW CWA TO 4-7 INCHES OVER THE FAR SW CWA ALONG THE WI BDR. WENT WITH ADVISORIES FOR MNM...DELTA AND ALGER COUNTIES WHERE 2-4 INCH AMOUNTS WILL BE MORE COMMON ON WED WITH MUCH OF THE SNOW FALLING IN THE AFTERNOON HRS. FARTHER EAST OVER SCHOOLCRAFT AND LUCE COUNTIES...LOW-LVL DRY AIRMASS INITIALLY IN PLACE FROM LINGERING SFC RDG AXIS WILL TAKE A BIT LONGER TO MOISTEN FM ISENTROPIC ASCENT SO ONLY EXPECT GENERALLY 1-2 INCHES OF SNOW THERE AND WILL HOLD OFF ON ANY HEADLINE THERE FOR NOW. IF TONIGHT/S MODEL RUNS CONTINUE TO TREND EASTWARD MAY NEED TO CONSIDER POSSIBILITY OF ADDING MNM AND POSSIBLY DELTA INTO WARNING. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 531 PM EDT TUE APR 15 2014 LONG TERM PORTION OF THE FCST WILL BEGIN COLD/WINTRY AS SHORTWAVE TAKES ADVANTAGE OF LINGERING TIGHT THERMAL GRADIENT OVER THE AREA BTWN DEPARTING UNUSUALLY COLD AIR MASS FOR MID APR AND WARMTH SPREADING OUT ACROSS THE CNTRL/SRN PLAINS. TEMPS WILL THEN SLOWLY MODERATE AS DEEP TROF AND ASSOCIATED LATE SEASON ARCTIC AIR LIFT TO GREENLAND...AND PACIFIC AIR MAKES INCREASING INROADS ACROSS THE CONUS AND SRN CANADA. HEADING DOWN THE ROAD...IT LOOKS LIKE TEMPS NEXT WEEK WILL GENERALLY FLUCTUATE AROUND NORMAL...BUT NOT SIGNIFICANTLY ABOVE OR BLO NORMAL DURING THE TEMP SWINGS. THERE ARE SOME INDICATIONS FROM GEM ENSEMBLES AND GFS RUNS THAT THE PATTERN MAY BE FAIRLY ACTIVE OVER THE NEXT COUPLE OF WEEKS WHICH WILL MEAN RAINFALL FOR MOST IF NOT ALL PCPN EVENTS. HOPEFULLY...SIGNIFICANT RAINFALL WILL BE AVOIDED AS THE SNOWMELT SEASON RESUMES. BEGINNING WED NIGHT...A HVY/WET SNOW EVENT WILL BE UNDERWAY AS SHORTWAVE APPROACHES FROM THE UPPER MISSISSIPPI VALLEY. WITH 12Z MODEL RUNS...MODELS THAT HAD MAX QPF AXIS ON THE NW SIDE OF THE MODEL SPREAD HAVE SHIFTED SLIGHTLY S AND E. RESULT IS IMPROVING MODEL AGREEMENT NOW ON WHERE AXIS OF HEAVIEST PCPN WILL SET UP. IT APPEARS MAX QPF AXIS SHOULD RUN ROUGHLY FROM JUST N OF THE TWIN CITIES TO THE HURON MTNS. THE NAM IS DISPLACED A LITTLE TO THE NW OF THIS AXIS WHILE THE GEM REGIONAL/HEMISPHERIC ARE DISPLACED A LITTLE TO THE SE. ALTHOUGH SFC LOW ASSOCIATED WITH SHORTWAVE WILL BE WEAKENING AS IT TRACKS FROM THE NRN/CNTRL PLAINS TO THE UPPER LAKES...BEST COMBINATION OF FORCING/MOISTURE WILL COME TOGETHER FROM ERN MN E AND NE NTO UPPER MI BEFORE SYSTEM BEGINS TO FALL APART. AT THE UPPER LEVELS...RIGHT ENTRANCE OF UPPER JET STREAK RUNNING FROM NRN LAKE SUPERIOR/NRN ONTARIO EASTWARD WILL PROVIDE HEALTHY UPPER DIVERGENCE. THERE ARE EVEN SOME HINTS OF BRIEF UPPER JET COUPLING WITH LEFT EXIT OF JET SHIFTING ACROSS THE UPPER MIDWEST THAT IS SUPPORTING THE SHORTWAVE. AT THE LOWER LEVELS...STRONG ISENTROPIC ASCENT IS NOTED WITH MIXING RATIOS OF 3 TO 4G/KG AVBL AROUND 700-750MB. IN ADDITION...THERE IS STRONG FRONTOGENESIS WITH NEGATIVE EPV/CONVECTIVE INSTABILITY NOTED OVERTOP THE FGEN. FINALLY...STEEP MIDLEVEL LAPSE RATES ARE NOTED ADVECTING INTO THE SRN SIDE OF THE PCPN AREA. ALL THIS POINTS TO THE LIKELIHOOD FOR HEAVIER BANDING OF SNOW WITHIN THE OVERALL MDT/HVY PCPN AREA OR EVEN CONVECTIVE SNOW AT TIMES...CERTAINLY NOT ATYPICAL FOR SPRINGTIME HVY SNOW EVENTS. ULTIMATE PLACEMENT OF HEAVIEST SNOW WILL HINGE ON WHERE THESE HEAVIER SNOWBANDS OR CONVECTIVE ELEMENTS SET UP. AS IT STANDS NOW...LOCATIONS W OF KIMT/KMQT LINE SHOULD HAVE NO PROBLEM REACHING WARNING CRITERIA WITH STORM TOTAL AMOUNTS AROUND 1 FOOT...PROBABLY IN MANY LOCATIONS. ADVY ISSUED FOR NEXT TIER OF COUNTIES E MAY IN FACT NEED TO BE UPGRADED TO WARNINGS GIVEN MODEL TRENDS. FINALLY... EVEN THE FAR E COUNTIES OF SCHOOLCRAFT AND LUCE MAY NEED TO BE ADDED TO AN ADVY IF THE E TREND HOLDS UP IN NEXT SET OF MODEL RUNS. PCPN WINDS DOWN QUICKLY THU AND WILL LIKELY END. SFC HIGH PRES THEN BUILDS INTO THE UPPER LAKES THU NIGHT THRU FRI NIGHT TO PROVIDE A PERIOD OF QUIET WEATHER. NAM IN PARTICULAR SUGGESTS LOW CLOUDS MAY LINGER THU NIGHT...AND THAT MAY BE THE CASE WITH SHALLOW COLD AIR MASS OVER EXPANDING OPEN WATER ON LAKE SUPERIOR. IF CLOUDS DO CLEAR OUT IN SOME AREAS THU NIGHT...EXPECT BKN DIURNAL CU DEVELOPMENT FRI UNDER MID LEVEL TROF AND ASSOCIATED THERMAL TROF. NOT OUT OF THE QUESTION THAT A FEW FLURRIES COULD EVEN DEVELOP. FRI HIGHS WILL BE IN THE 30S N WITH A CHILLY WIND OFF THE ICE TO THE 40S S. WITH CLOUDS CLEARING OUT FRI NIGHT...IT WILL BE A COLD NIGHT WITH HIGH PRES STILL OVER THE AREA. FAVORED THE LOWER SIDE OF GUIDANCE WITH SOME TEENS OVER THE W WHERE WINDS WILL BE LIGHTEST. COULD BE CONSIDERABLY COLDER ACROSS ALL OF THE INTERIOR IF SKIES CLEAR EARLY AND STAY THAT WAY FOR A GOOD PART OF THE NIGHT. MODELS THEN DIVERGE WITH PROGRESSION OF NEXT SHORTWAVE FEATURE MOVING OFF THE PACIFIC IN LOWER AMPLITUDE FLOW...THOUGH AGREEMENT IS IMPROVING WITH TODAYS 12Z MODEL RUNS. GEM IS STRONGER WITH WAVE AND IS HEAVIER WITH THE QPF THAN THE GFS/ECWMF. HOWEVER...BOTH THE GFS AND ECMWF ARE TRENDING TOWARD A WETTER SYSTEM NOW. SOME -RA POSSIBLY MIXED WITH A LITTLE SNOW OVER HIGHER TERRAIN WILL PROBABLY REACH THE W SAT AFTN...THEN SPREAD E SAT NIGHT/SUN. WITH WETTER TRENDS NOTED...WILL TRENDING POPS UP TO CHC. MON/TUE...ECMWF HAS BEEN CONSISTENT SHOWING TROF DEVELOPMENT INTO THE W COAST WITH DOWNSTREAM RIDGE BUILDING INTO THE ROCKIES/WRN PLAINS WHILE TROF SETTLES INTO THE ERN CONUS. THE GFS IS CONSIDERABLY MORE PRONOUNCED WITH EASTWARD EXTENT OF RIDGE/HIGHER HEIGHTS INTO THE GREAT LAKES...BUT THE 12Z GFS IS NOW SHOWING SIGNS OF HEADING IN THE DIRECTION OF THE ECMWF. WILL LEAN TOWARD THE MORE CONSISTENT ECMWF WHICH TYPICALLY VERIFIES BETTER. RESULT IS A COOLER THAN GFS SCENARIO...BUT STILL CLOSE TO NORMAL FOR TEMPS. IF ANY MINOR WAVES TRACK SE ACROSS THE AREA INTO THE ERN TROF...THERE MAY BE SOME SCT LIGHT -SHRA AT TIMES. AT THIS POINT...NOTHING SUGGESTS THE NEED FOR AN EXPLICIT MENTION OF PCPN MON OR TUE. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING) ISSUED AT 741 PM EDT TUE APR 15 2014 HIGH PRESSURE BUILDING IN ACROSS THE U.P. WILL HELP TO KEEP WINDS LIGHT AND VARIABLE THROUGH TONIGHT. ANY LINGERING DIURNAL SNOW SHOWERS WILL QUICKLY DISSIPATE THIS EVENING. ALL SITES EXCEPT FOR THE KSAW TAF SITE HAVE CLEARED OUT AS OF 00Z/15. DURING THE DAY WEDNESDAY...ATTENTION WILL TURN TO AN APPROACHING LOW PRESSURE SYSTEM. IWD WILL BE THE FIRST TO SEE THE SNOWFALL AROUND 14Z...THEN THE SNOW WILL SPREAD TO CMX AND KSAW THROUGH THE REMAINDER OF THE DAY. HAVE TRENDED THE VISIBILITY LOWER TOWARD THE END OF THE TAF PERIOD AS HEAVIER SNOW AND STRONGER WINDS BEGIN TO PUSH INTO EACH OF THE TAF SITES. IWD WAS KEPT A BIT LOWER THAN THE OTHER TAF SITES AS THE HEAVIER SNOW WOULD APPROACH THAT AREA FIRST. ADDITIONALLY...CEILING HEIGHTS WILL DECREASE AS THE UPPER LEVEL TROUGH AND MAIN SURFACE LOW MOVE CLOSER TO THE REGION TOWARD THE END OF THE TAF PERIOD. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 531 PM EDT TUE APR 15 2014 WINDS LESS THAN 20 KTS THROUGH TONIGHT WITH SFC HIGH PRES RIDGE OVER THE AREA. APPROACHING LOW PRESSURE SYSTEM FM THE PLAINS WILL RESULT IN INCREASING EAST TO NORTHEAST WINDS ON WEDNESDAY. WENT WITH A GALE WARNING FOR FAR WRN LAKE SUPERIOR WEDNESDAY AFTN INTO THU MORNING AS WINDS ARE ENHANCED DUE TO CHANNELING AND TERRAIN EFFECTS. WINDS SHIFT TO THE NORTH-NORTHWEST TO 25 KTS BY THURSDAY AFTERNOON AS THE LOW WEAKENS WHILE MOVING OVER ERN LK SUPERIOR. EXPECT WINDS STAY BLO 20 KTS FOR THE REST OF THE FORECAST PERIOD. && .HYDROLOGY... ISSUED AT 531 PM EDT TUE APR 15 2014 RECENT COLDER WEATHER AND CONTINUATION OF COLDER WEATHER FOR THE NEXT FEW DAYS WILL RESULT IN SLOW RUNOFF OF MELTING SNOW. THUS... RIVER LEVELS SHOULD NOT SHOW ANY SIGNIFICANT FLUCTUATIONS. HOWEVER...ICE JAMS COULD BE AN ISSUE AS THEY HAVE BEEN IN SOME AREAS. HOWEVER...DIMINISHED RUNOFF SHOULD REDUCE THE POTENTIAL FOR ADDITIONAL ICE JAMS. WIDESPREAD PRECIPITATION IS IN THE FORECAST FOR WEDNESDAY THROUGH THURSDAY MORNING WITH THE POTENTIAL FOR 0.50 TO 1.25 INCHES OF LIQUID EQUIVALENT PRECIPITATION...GREATEST OVER THE W HALF OF UPPER MICHIGAN. THIS PRECIP ADDED TO EXISTING SNOWPACK WITH WATER EQUIVALENT OF 4-9 INCHES WILL RESULT IN ANOTHER PERIOD OF SNOWMELT RUNOFF/RIVER RISES AND POSSIBLE ICE JAMS ONCE WARMER TEMPERATURES ARRIVE NEXT WEEK. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... WINTER WEATHER ADVISORY FROM NOON WEDNESDAY TO NOON EDT THURSDAY FOR MIZ006-013. WINTER STORM WARNING FROM NOON WEDNESDAY TO 11 AM EDT THURSDAY FOR MIZ004-084. WINTER STORM WARNING FROM NOON WEDNESDAY TO NOON EDT THURSDAY FOR MIZ005. WINTER STORM WARNING FROM 11 AM EDT /10 AM CDT/ WEDNESDAY TO 11 AM EDT /10 AM CDT/ THURSDAY FOR MIZ002-009>011. WINTER STORM WARNING FROM 2 PM WEDNESDAY TO NOON EDT THURSDAY FOR MIZ001-003. WINTER WEATHER ADVISORY FROM 9 AM WEDNESDAY TO 10 AM CDT THURSDAY FOR MIZ012. LAKE SUPERIOR... GALE WARNING FROM 2 PM EDT /1 PM CDT/ WEDNESDAY TO 11 AM EDT /10 AM CDT/ THURSDAY FOR LSZ162. LAKE MICHIGAN... NONE. && $$ SHORT TERM...VOSS LONG TERM...ROLFSON AVIATION...KEC MARINE...VOSS HYDROLOGY...ROLFSON
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
144 PM EDT MON APR 14 2014 LATEST UPDATE... AVIATION .SYNOPSIS... ISSUED AT 325 AM EDT MON APR 14 2014 A LOW PRESSURE SYSTEM CENTERED NEAR CHICAGO EARLY THIS MORNING WILL CONTINUE TO BRING RAIN SHOWERS TODAY. PRECIPITATION WILL GRADUALLY BECOME MIXED WITH AND CHANGE OVER TO SNOW SHOWERS AS COLDER AIR MOVES IN ON THE BACK SIDE OF A LOW PRESSURE SYSTEM THAT WILL CONTINUE TO TRACK NORTHEAST INTO ONTARIO. IT WILL BE BREEZY TODAY AS WELL. TEMPERATURES WILL BE UNSEASONABLY COLD TUESDAY BEFORE UNDERGOING A MODERATING TREND WEDNESDAY THROUGH THURSDAY. && .UPDATE... ISSUED AT 1209 PM EDT MON APR 14 2014 SENT AN UPDATE TO MAKE SOME MINOR ADJUSTMENTS TO THE FORECAST...BUT OVERALL THINGS PROGRESSING AS EXPECTED. TEMPERATURES PLUNGED BEHIND THE COLD FRONT THIS MORNING WHICH HAS NOW PROGRESSED JUST EAST OF THE FORECAST AREA INTO SOUTHEAST LOWER. GRAND RAPIDS DROPPED ABOUT 20 DEGREES IN AN HOUR WITH THE FRONTAL PASSAGE. EXPECTING THE TEMPERATURES TO CONTINUE A SLOW FALL THIS AFTERNOON ON NORTHERLY COLD AIR ADVECTION WINDS. BY EVENING TEMPERATURES WILL RANGE FROM THE UPPER 20S TOWARD LUDINGTON TO THE UPPER 30S AT JACKSON. SKIES WILL REMAIN MOSTLY CLOUDY THIS AFTERNOON WITH NORTH-NORTHWEST WINDS OF 15-25 MPH. && .SHORT TERM...(TODAY THROUGH WEDNESDAY) ISSUED AT 325 AM EDT MON APR 14 2014 SHOWERS WILL CONTINUE TO LINGER THIS MORNING AS LOW PRESSURE NEAR ORD EARLY THIS MORNING TRACKS NE TO SAGINAW BAY BY 12Z AND FURTHER NE INTO ONTARIO BY MIDDAY. FAIRLY WINDY CONDITIONS ARE ANTICIPATED TODAY AS BRISK NW FLOW CAA OCCURS ON THE BACK SIDE OF THE SYSTEM. GUSTY WINDS ARE ALREADY NOTED OVER NORTH/CENTRAL IL INTO NORTHERN INDIANA. HIGHER RES GUIDANCE SUCH AS THE HRRR SUGGESTS SOME GUSTS MAY BRIEFLY REACH AROUND 40 TO NEAR 45 MPH ALONG I-94 AND ESPECIALLY IN OUR FAR SE FCST AREA TOWARD JXN LATER THIS MORNING. THIS IN ADDITION TO A FEW GUSTS TO AROUND 40 TO 45 MPH RIGHT ALONG THE LAKE MI SHORELINE. OVERALL THOUGH FELT A WIND ADVISORY IS NOT NEEDED TODAY SINCE THE MAJORITY OF OUR AREA WILL NOT SEE GUSTS AS HIGH AS 45 MPH. PCPN WILL GRADUALLY BECOME MIXED WITH THEN CHANGE OVER TO LIGHT SNOW SHOWERS FROM NW TO SE ACROSS OUR FCST AREA TODAY AS THE CAA OCCURS. VERY LITTLE TO NO ACCUMULATION IS EXPECTED TODAY. HOWEVER AS TEMPERATURES CONTINUE TO FALL INTO THE 20S TONIGHT WE DO EXPECT LIGHT ACCUMULATIONS ACROSS MOST OF OUR FCST AREA RANGING FROM A FEW TENTHS OF AN INCH TO LOCALLY AS MUCH AS TWO INCHES. LINGERING LIGHT SNOW SHOWERS TUESDAY MORNING WILL TAPER OFF TO FLURRIES BEFORE ENDING AND IT WILL BE UNSEASONABLY COLD WITH MAX TEMPS ONLY IN THE 30S. HIGH PRESSURE WILL BUILD IN TO PRODUCE FAIR BUT COLD WX TUESDAY NIGHT. FAIR WX WILL CONTINUE WEDNESDAY ALONG WITH MUCH MILDER TEMPS AS FLOW BECOMES SOUTHERLY ON THE BACKSIDE OF THE DEPARTING HIGH. .LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY) ISSUED AT 325 AM EDT MON APR 14 2014 NO BIG STORMS EXPECTED IN THE EXTENDED PERIOD. THERE WILL BE SOME RAIN BUT CONVECTION IS NOT LIKELY SO AMOUNTS SHOULD NOT BE EXCESSIVE. TWO LOW PRESSURE CENTERS WILL BE MOVING THROUGH FROM WEDNESDAY NIGHT INTO SATURDAY NIGHT WITH THE HIGHEST CHANCES FOR RAIN ON FRIDAY NIGHT. MODEL SOUNDINGS SUGGEST RAIN COULD MIX WITH WET SNOW ACROSS THE NORTH WEDNESDAY NIGHT AND AGAIN SATURDAY NIGHT BUT CONDITIONS WERE MARGINAL ENOUGH TO LEAVE OUT OF THE FORECAST. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 140 PM EDT MON APR 14 2014 A DEEP TROUGH IS APPROACHING AND WILL SPREAD LIGHT SNOW INTO THE AREA THIS EVENING. SOLID MVFR CONDITIONS EXPECTED. THE PERIOD OF SNOW LOOKS TO BE FROM AROUND 01Z THROUGH 09Z OR SO. A FEW LAKE EFFECT SNOW SHOWERS MAY FALL AT THE WESTERN TAF SITES TUESDAY BUT VFR CONDITIONS EXPECTED. && .HYDROLOGY... ISSUED AT 1209 PM EDT MON APR 14 2014 AREAL FLOOD WARNINGS REMAIN ACROSS CENTRAL LOWER MICHIGAN. WIDESPREAD FLOODING CONTINUES IN LOW LYING AREAS AS WELL AS WHERE SMALLER CREEKS AND STREAMS HAVE COME OUT OF THERE BANKS. ON TOP OF THAT THE 3-5 INCHES OF RAIN THAT FELL ACROSS CENTRAL LOWER MICHIGAN HAS RESULTED IN SIGNIFICANT MAINSTEM RIVERS FLOODING. EVART IS FORECAST TO GO TO NEAR RECORD FLOODING AT 15.0 FT. THE BULK OF THE FLOODING ISSUES ARE ACROSS THE PERE MARQUETTE...WHITE... MUSKEGON... PINE AND CHIPPEWA RIVER BASINS. THE ONLY RIVER WARNING IN THE GRAND RIVER BASIN IS THE ROGUE AT ROCKFORD. THE NORTHERN PORTIONS OF THIS RIVER BASIN SAW HEAVIER RAINS THAT WILL ROUTE DOWNSTREAM IN THE NEXT COUPLE DAYS. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...NONE. LM...NONE. && $$ UPDATE...DUKE SYNOPSIS...LAURENS SHORT TERM...LAURENS LONG TERM...OSTUNO AVIATION...93 HYDROLOGY...DUKE
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
109 PM EDT MON APR 14 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 533 AM EDT MON APR 14 2014 WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL RIDGE OVER THE WEST COAST AND A DOWNSTREAM TROUGH FROM HUDSON BAY THE NRN AND CNTRL PLAINS. A POTENT WELL DEFINED SHORTWAVE TROUGH WITH COMMA RADAR SIGNATURE WAS LIFTING NORTHEAST INTO SW WI. THE COMBINATION OF UPPER LEVEL DIV WITH THE RIGHT ENTRANCE OF THE 140-150 KNOT 300 MB JET OVER NRN ONTARIO...STRONG QVECTOR CONV AND 700-500 MB FGEN SUPPORTED MODERATE TO HEAVY SNOW FROM N CNTRL WI THROUGH CNTRL UPPER MI. RADAR INDICATED THE HIGHER REFLECTIVITY ALIGNED WITH THE MAX FGEN FROM NEAR IMT TO SE MARQUETTE COUNTY. TWO TO THREE INCHES HAD FALLEN IN MANY LOCATIONS OF CNTRL UPPER MI BY 09Z WITH ONE INCH TO THE SE AT ISQ. GIVEN THE WET HEAVY NATURE OF THE SNOW...SLR VALUES WERE LOW...GENERALLY AT OR BELOW 10/1. TODAY...AS THE SHORTWAVE LIFTS TO THE NORTHEAST...EXPECT THE SNOW TO GRADUALLY DIMINISH THIS MORNING AROUND 15Z. ADDITIONAL ACCUMULATIONS OF 2 TO 3 INCHES WOULD BRING TOTALS INTO THE 3 TO 6 INCH RANGE. THE STRONG UPSLOPE NRLY FLOW WILL ALSO HELP BOOST SNOW AMOUNTS TOWARD THE HIGHER END OF THE RANGE OVER THE HIGHER TERRAIN OF N CNTRL UPPER MI. ALTHOUGH WINDS GUSTING TO 35 MPH WILL ALSO PRODUCE BLOWING SNOW...THE SNOW WAS WET ENOUGH SO THAT VSBYS WERE MAINLY ABOVE 1/2SM. SOME LOCALIZED LOWER VSBY WOULD BE EXPECTED NEAR THE LAKE SUPERIOR SHORELINE. AS THE STRONGER DYNAMICS LIFT OUT BY THIS AFTERNOON SOME LIGHT SNOW WILL CONTINUE INTO THE NORTH AS 850 MB TEMPS DROPPING TO AROUND -16C AND SOME LIMITED OPEN WATER PROVIDES ENOUGH HEAT/MOISTURE FOR ADDITIONAL LAKE EFFECT AND OROGRAPHIC SNOW FOR HIGHER TERRAIN LOCATIONS. TONIGHT...ANY LINGERING LAKE EFFECT SNOW WILL DIMINISH BUT COULD STILL PRODUCE A DUSTING OVER THE NORTH. MUCH COLDER AIR WILL MOVE IN WITH MIN READINGS INTO THE 5F TO 15F RANGE. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 417 AM EDT MON APR 14 2014 LONGWAVE TROUGH AXIS ACROSS THE GREAT LAKES ON TUESDAY. QUITE CHILLY WITHIN THE TROUGH WITH H85 TEMPS DOWN TO -20C OVER LK SUPERIOR. SHORTWAVE DROPPING SE IN THE MEAN TROUGH INCREASES DEPTH OF QUALITY OF MOISTURE AND ALSO STEEPENS H9-H7 LAPSE RATES ON TUESDAY. LAKE EFFECT FLURRIES MAY TRANSITION TO DIURNALLY DRIVEN SNOW SHOWERS WITH COVERAGE EXTENDING INLAND TOWARD WI BORDER AND LK MICHIGAN SHORE. POPS LOW CHANCE AT BEST THOUGH. TEMPS WILL BE VERY COOL FOR THIS TIME OF YEAR WITH READINGS IN THE LOW-MID 20S NORTH AND AROUND 30 IN THE SOUTHERN CWA. NORMAL HIGHS ARE INTO THE LOWER 50S OVER THE SOUTH. WAVE MOVES EAST ON TUESDAY EVENING WHICH SHOULD ALLOW SKIES TO TEMPORARILY CLEAR OUT AHEAD OF NEXT SYSTEM THAT BEGINS TO IMPACT FAR WEST CWA WITH LGT SNOW LATE TUESDAY NIGHT. MIN TEMPS MAY DIP INTO SINGLE DIGITS FOR MANY AREAS BEFORE THICKER CLOUDS MOVE BACK IN LATER DURING THE NIGHT. WHAT TO DO WITH SYSTEM FOR WEDNESDAY WILL BECOME LARGER FOCUS ONCE WE GET PAST SYSTEM BRINGING SNOW TO MUCH OF UPR MICHIGAN TODAY. WILL TWO CAMPS STILL PRESENT IN THE MODELS. NAM/GFS BRING SHORTWAVE AND SFC LOW PRESSURE AND INVERTED TROUGH ACROSS UPPER MISSISSIPPI RIVER VALLEY QUICKER...AND HAVE MORE QPF. BOTH CAMPS OF MODELS GENERATE QPF INTO WESTERN CWA BY 12Z WEDNESDAY...SUPPORTED BY LARGER SCALE DIFFLUENCE ALOFT BTWN JETS EMERGING FM THE PLAINS AND CROSSING LK SUPERIOR REGION. ECMWF AND GEM-NH AND UKMET ARE SLOWER AND NOT AS HEAVY WITH QPF OVER UPR MICHIGAN...KEEPING FOCUS FOR HEAVIER PRECIP OVER CNTRL MN INTO WCNTRL WI ALONG TRACK OF SFC LOW PRESSURE WAVE THROUGH MUCH OF WEDNESDAY BEFORE LIFTING IT ACROSS MAINLY WESTERN HALF OF UPR MICHIGAN LATER WEDNESDAY INTO WEDNESDAY NIGHT. DESPITE MODEL DIFFERENCES...ENOUGH EVIDENCE TO PUSH POPS TO LIKELY WEDNESDAY AND WEDNESDAY NIGHT. ALSO THERE IS DECENT AGREEMENT THAT WESTERN AND PROBABLY CENTRAL CWA WILL SEE MODERATE SNOW AMOUNTS FROM THIS SYSTEM...WITH BULK OF SNOW FALLING WEDNESDAY AFTN THROUGH EARLY THURSDAY MORNING. MIXING RATIOS 2.5-3G/KG WOULD SUPPORT MODERATE SNOW AMOUNTS OF 3 TO 6 INCHES OVER 12 HOUR PERIOD. MODELS SHOWING AREA OF MID-LEVEL FGEN...FAIRLY STRONG CONSIDERING HOW FAR OUT WE ARE STILL...THAT COULD RESULT IN BANDS OF HEAVIER SNOW OVER LIKELY THE WEST CWA. HPC HEAVY SNOW GRAPHICS SHOW MUCH OF FAVORED AREA WITH MODERATE PROBABILITY OF SEEING 4 INCHES OF SNOW WITH LOW PROBABILITY OF SEEING 8 INCHES. BASED ON 1000-850MB AND 850-700MB THICKNESSES AND H85 TEMPS...SNOW WILL MIX WITH AND COULD CHANGE TO RAIN LATER WEDNESDAY NIGHT OVER SCNTRL AND EAST CWA. RAIN/SNOW MIX CONTINUES INTO THURSDAY FOR THOSE AREAS WHILE WIDESPREAD SNOW DIMINISHES ELSEWHERE. NO WATCH ATTM...AS IT WOULD BE LATER 5TH PERIOD AND STILL NEED TO GET THROUGH THIS ONGOING SNOW SYSTEM TO AVOID ANY CONFUSION. WILL CONTINUE TO MENTION IN EHWO/HWOMQT. LATER THURSDAY AND ON INTO NEXT WEEKEND THE FORECAST IS AT BEST MUDDLED...WHICH LEADS TO LOWER THAN AVERAGE CONFIDENCE FOR SURE. GFS MORE OR LESS IS FAIRLY CONSISTENT IN SHOWING SHORTWAVE IN SOUTHERN STREAM LIFTING ACROSS UPPER GREAT LAKES WHILE PHASING WITH NORTHERN BRANCH SHORTWAVE TROUGH. RESULT IS WRAPPED UP SFC LOW WITH WIDESPREAD RAIN AND SNOW OVER UPR MICHIGAN. GEM-NH SUPPORTS IDEA SOMEWHAT THOUGH IT IS SLOWER AND NOT AS STRONG. ECMWF WAS TRENDING NORTH AND WEST WITH THAT SYSTEM...BUT WITH LATEST RUN NOW HAS WENT BACK TO THE SOUTHEAST...KEEPING MUCH OF UPR MICHIGAN DRY ON FRIDAY. ECMWF IS NOT PHASING THE SOUTHERN WAVE NEAR AS MUCH AS GFS ATTEMPTS TO SHOW. CONSENSUS POPS...CAPPED AT LOW CHANCE...WILL BE UTILIZED FOR NOW. WHATEVER LOW PRESSURE SYSTEM WOULD BE EXITING TO START THE WEEKEND...WITH HIGH PRESSURE AND DRIER WEATHER FOR THE REST OF THE WEEKEND AS SHOWN BY GFS. NOT SO INDICATES THE ECMWF...WITH A QUICK PUSH OF NEXT SHORTWAVE ENERGY AND SFC TROUGH/RAIN SHOWERS FOR SUNDAY. LATEST RUN BACKED OFF SOME...BUT JUST SHOWS THE HIGH VARIABILITY THAT CURRENTLY EXISTS FOR THAT FORECAST TIME FRAME. ONE PRETTY SURE THING IS IT LOOKS LIKE WARMING TREND /TEMPS TRYING TO RETURN TOWARD AVERAGE/ DEVELOPS NEXT WEEKEND AFTER WHAT APPEARS TO BE A CHILLY MID APRIL WEEK. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 108 PM EDT MON APR 14 2014 AT SAW...LIFR CONDITIONS WILL GRADUALLY IMRPROVE TO MVFR BY MID AFTERNOON AS THE ARRIVAL OF DRIER AIR...DAYTIME HEATING AND SLOWLY WEAKENING PRES GRADIENT/WINDS ARRIVE. MVFR CONDITIONS WILL PREDOMINATE THROUGH THE REST OF THE FCST PERIOD. IWD/CMX...MVFR CONDITIONS WILL CONTINUE THROUGH THE PERIOD WITH LAKE EFFECT CLOUDS AROUND CAUSING MVFR CIGS. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 417 AM EDT MON APR 14 2014 NORTH GALES 35-40 KNOTS FOR TODAY...MAINLY EAST HALF...AS LOW PRESSURE SYSTEM TRACKS ACROSS LOWER MICHIGAN THIS MORNING AND EVENTUALLY ACROSS QUEBEC BY THIS EVENING. WINDS QUICKLY DIMINISH BY THIS EVENING AND SHOULD REMAIN BLO 20 KTS OVER MOST OF THE LAKE THROUGH TUESDAY. LOW PRESSURE SYSTEM LIFTING ACROSS UPPER GREAT LAKES LATER ON WEDNESDAY WILL RESULT IN EAST TO NORTHEAST WINDS UP TO 25 KTS OVER MAINLY WESTERN LAKE INTO THURSDAY. WINDS DIMINISH TO LESS THAN 20 KTS REST OF THE FORECAST PERIOD. && .HYDROLOGY... ISSUED AT 417 AM EDT MON APR 14 2014 REPORTS OF ICE JAMS IN DELTA COUNTY SUNDAY ON ESCANABA RIVER AND ASSOCIATED TRIBUTARIES. HYDROLOGIC STATEMENT WAS ISSUED SUNDAY EVENING AND THIS IS VALID THROUGH THIS EVENING. PRECIPITATION OCCURS MAINLY IN THE FORM OF SNOW TODAY. OPPORTUNITIES FOR WIDESPREAD PRECIPITATION ALSO IN THE FORECAST FOR WEDNESDAY THROUGH THURSDAY... AND POSSIBLY FRIDAY. FEASIBLE THAT TOTAL PRECIPITATION FOR THIS WEEK MAY EXCEED AN INCH IN SOME AREAS OF UPPER MICHIGAN. THIS PRECIP ADDED TO EXISTING SNOWPACK WITH WATER EQUIVALENT OF 4-9 INCHES OVER MAINLY WESTERN UPPER MICHIGAN WILL RESULT IN ANOTHER PERIOD OF SNOWMELT AND RUNOFF ONCE WARMER TEMPERATURES MOVE BACK INTO THE REGION BY NEXT WEEKEND. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... WINTER WEATHER ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR MIZ007- 013-014-085. LAKE SUPERIOR... GALE WARNING UNTIL 5 PM EDT THIS AFTERNOON FOR LSZ249>251-266- 267. GALE WARNING UNTIL 2 PM EDT THIS AFTERNOON FOR LSZ244-245-264- 265. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...JLA AVIATION...07 MARINE...JLA HYDROLOGY...JLA
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1210 PM EDT MON APR 14 2014 LATEST UPDATE... UPDATE/HYDRO .SYNOPSIS... ISSUED AT 325 AM EDT MON APR 14 2014 A LOW PRESSURE SYSTEM CENTERED NEAR CHICAGO EARLY THIS MORNING WILL CONTINUE TO BRING RAIN SHOWERS TODAY. PRECIPITATION WILL GRADUALLY BECOME MIXED WITH AND CHANGE OVER TO SNOW SHOWERS AS COLDER AIR MOVES IN ON THE BACK SIDE OF A LOW PRESSURE SYSTEM THAT WILL CONTINUE TO TRACK NORTHEAST INTO ONTARIO. IT WILL BE BREEZY TODAY AS WELL. TEMPERATURES WILL BE UNSEASONABLY COLD TUESDAY BEFORE UNDERGOING A MODERATING TREND WEDNESDAY THROUGH THURSDAY. && .UPDATE... ISSUED AT 1209 PM EDT MON APR 14 2014 SENT AN UPDATE TO MAKE SOME MINOR ADJUSTMENTS TO THE FORECAST...BUT OVERALL THINGS PROGRESSING AS EXPECTED. TEMPERATURES PLUNGED BEHIND THE COLD FRONT THIS MORNING WHICH HAS NOW PROGRESSED JUST EAST OF THE FORECAST AREA INTO SOUTHEAST LOWER. GRAND RAPIDS DROPPED ABOUT 20 DEGREES IN AN HOUR WITH THE FRONTAL PASSAGE. EXPECTING THE TEMPERATURES TO CONTINUE A SLOW FALL THIS AFTERNOON ON NORTHERLY COLD AIR ADVECTION WINDS. BY EVENING TEMPERATURES WILL RANGE FROM THE UPPER 20S TOWARD LUDINGTON TO THE UPPER 30S AT JACKSON. SKIES WILL REMAIN MOSTLY CLOUDY THIS AFTERNOON WITH NORTH-NORTHWEST WINDS OF 15-25 MPH. && .SHORT TERM...(TODAY THROUGH WEDNESDAY) ISSUED AT 325 AM EDT MON APR 14 2014 SHOWERS WILL CONTINUE TO LINGER THIS MORNING AS LOW PRESSURE NEAR ORD EARLY THIS MORNING TRACKS NE TO SAGINAW BAY BY 12Z AND FURTHER NE INTO ONTARIO BY MIDDAY. FAIRLY WINDY CONDITIONS ARE ANTICIPATED TODAY AS BRISK NW FLOW CAA OCCURS ON THE BACK SIDE OF THE SYSTEM. GUSTY WINDS ARE ALREADY NOTED OVER NORTH/CENTRAL IL INTO NORTHERN INDIANA. HIGHER RES GUIDANCE SUCH AS THE HRRR SUGGESTS SOME GUSTS MAY BRIEFLY REACH AROUND 40 TO NEAR 45 MPH ALONG I-94 AND ESPECIALLY IN OUR FAR SE FCST AREA TOWARD JXN LATER THIS MORNING. THIS IN ADDITION TO A FEW GUSTS TO AROUND 40 TO 45 MPH RIGHT ALONG THE LAKE MI SHORELINE. OVERALL THOUGH FELT A WIND ADVISORY IS NOT NEEDED TODAY SINCE THE MAJORITY OF OUR AREA WILL NOT SEE GUSTS AS HIGH AS 45 MPH. PCPN WILL GRADUALLY BECOME MIXED WITH THEN CHANGE OVER TO LIGHT SNOW SHOWERS FROM NW TO SE ACROSS OUR FCST AREA TODAY AS THE CAA OCCURS. VERY LITTLE TO NO ACCUMULATION IS EXPECTED TODAY. HOWEVER AS TEMPERATURES CONTINUE TO FALL INTO THE 20S TONIGHT WE DO EXPECT LIGHT ACCUMULATIONS ACROSS MOST OF OUR FCST AREA RANGING FROM A FEW TENTHS OF AN INCH TO LOCALLY AS MUCH AS TWO INCHES. LINGERING LIGHT SNOW SHOWERS TUESDAY MORNING WILL TAPER OFF TO FLURRIES BEFORE ENDING AND IT WILL BE UNSEASONABLY COLD WITH MAX TEMPS ONLY IN THE 30S. HIGH PRESSURE WILL BUILD IN TO PRODUCE FAIR BUT COLD WX TUESDAY NIGHT. FAIR WX WILL CONTINUE WEDNESDAY ALONG WITH MUCH MILDER TEMPS AS FLOW BECOMES SOUTHERLY ON THE BACKSIDE OF THE DEPARTING HIGH. .LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY) ISSUED AT 325 AM EDT MON APR 14 2014 NO BIG STORMS EXPECTED IN THE EXTENDED PERIOD. THERE WILL BE SOME RAIN BUT CONVECTION IS NOT LIKELY SO AMOUNTS SHOULD NOT BE EXCESSIVE. TWO LOW PRESSURE CENTERS WILL BE MOVING THROUGH FROM WEDNESDAY NIGHT INTO SATURDAY NIGHT WITH THE HIGHEST CHANCES FOR RAIN ON FRIDAY NIGHT. MODEL SOUNDINGS SUGGEST RAIN COULD MIX WITH WET SNOW ACROSS THE NORTH WEDNESDAY NIGHT AND AGAIN SATURDAY NIGHT BUT CONDITIONS WERE MARGINAL ENOUGH TO LEAVE OUT OF THE FORECAST. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING) ISSUED AT 744 PM EDT SUN APR 13 2014 IMPACTS WILL INCREASE THROUGH THE NIGHT FOR AVIATORS. IFR LOOKS LIKELY ESPECIALLY KGRR AND KMKG WITH THE HEAVIER RAIN. THUNDERSTORMS WILL BE AROUND AS WELL ESPECIALLY WEST OF KLAN AND KJXN. WINDS WILL INCREASE AND VALUES OVER 30 KTS EXPECTED. A SHARP WIND SHIFT IS EXPECTED MONDAY MORNING INTO THE AFTERNOON. TEMPERATURES WILL TURN COLDER AFTER THE WIND SHIFT. ICING MAY BECOME AN ISSUE MONDAY AFTERNOON. && .HYDROLOGY... ISSUED AT 1209 PM EDT MON APR 14 2014 AREAL FLOOD WARNINGS REMAIN ACROSS CENTRAL LOWER MICHIGAN. WIDESPREAD FLOODING CONTINUES IN LOW LYING AREAS AS WELL AS WHERE SMALLER CREEKS AND STREAMS HAVE COME OUT OF THERE BANKS. ON TOP OF THAT THE 3-5 INCHES OF RAIN THAT FELL ACROSS CENTRAL LOWER MICHIGAN HAS RESULTED IN SIGNIFICANT MAINSTEM RIVERS FLOODING. EVART IS FORECAST TO GO TO NEAR RECORD FLOODING AT 15.0 FT. THE BULK OF THE FLOODING ISSUES ARE ACROSS THE PERE MARQUETTE...WHITE... MUSKEGON... PINE AND CHIPPEWA RIVER BASINS. THE ONLY RIVER WARNING IN THE GRAND RIVER BASIN IS THE ROGUE AT ROCKFORD. THE NORTHERN PORTIONS OF THIS RIVER BASIN SAW HEAVIER RAINS THAT WILL ROUTE DOWNSTREAM IN THE NEXT COUPLE DAYS. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...NONE. LM...NONE. && $$ UPDATE...DUKE SYNOPSIS...LAURENS SHORT TERM...LAURENS LONG TERM...OSTUNO AVIATION...MJS HYDROLOGY...DUKE
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
751 AM EDT MON APR 14 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 533 AM EDT MON APR 14 2014 WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL RIDGE OVER THE WEST COAST AND A DOWNSTREAM TROUGH FROM HUDSON BAY THE NRN AND CNTRL PLAINS. A POTENT WELL DEFINED SHORTWAVE TROUGH WITH COMMA RADAR SIGNATURE WAS LIFTING NORTHEAST INTO SW WI. THE COMBINATION OF UPPER LEVEL DIV WITH THE RIGHT ENTRANCE OF THE 140-150 KNOT 300 MB JET OVER NRN ONTARIO...STRONG QVECTOR CONV AND 700-500 MB FGEN SUPPORTED MODERATE TO HEAVY SNOW FROM N CNTRL WI THROUGH CNTRL UPPER MI. RADAR INDICATED THE HIGHER REFLECTIVITY ALIGNED WITH THE MAX FGEN FROM NEAR IMT TO SE MARQUETTE COUNTY. TWO TO THREE INCHES HAD FALLEN IN MANY LOCATIONS OF CNTRL UPPER MI BY 09Z WITH ONE INCH TO THE SE AT ISQ. GIVEN THE WET HEAVY NATURE OF THE SNOW...SLR VALUES WERE LOW...GENERALLY AT OR BELOW 10/1. TODAY...AS THE SHORTWAVE LIFTS TO THE NORTHEAST...EXPECT THE SNOW TO GRADUALLY DIMINISH THIS MORNING AROUND 15Z. ADDITIONAL ACCUMULATIONS OF 2 TO 3 INCHES WOULD BRING TOTALS INTO THE 3 TO 6 INCH RANGE. THE STRONG UPSLOPE NRLY FLOW WILL ALSO HELP BOOST SNOW AMOUNTS TOWARD THE HIGHER END OF THE RANGE OVER THE HIGHER TERRAIN OF N CNTRL UPPER MI. ALTHOUGH WINDS GUSTING TO 35 MPH WILL ALSO PRODUCE BLOWING SNOW...THE SNOW WAS WET ENOUGH SO THAT VSBYS WERE MAINLY ABOVE 1/2SM. SOME LOCALIZED LOWER VSBY WOULD BE EXPECTED NEAR THE LAKE SUPERIOR SHORELINE. AS THE STRONGER DYNAMICS LIFT OUT BY THIS AFTERNOON SOME LIGHT SNOW WILL CONTINUE INTO THE NORTH AS 850 MB TEMPS DROPPING TO AROUND -16C AND SOME LIMITED OPEN WATER PROVIDES ENOUGH HEAT/MOISTURE FOR ADDITIONAL LAKE EFFECT AND OROGRAPHIC SNOW FOR HIGHER TERRAIN LOCATIONS. TONIGHT...ANY LINGERING LAKE EFFECT SNOW WILL DIMINISH BUT COULD STILL PRODUCE A DUSTING OVER THE NORTH. MUCH COLDER AIR WILL MOVE IN WITH MIN READINGS INTO THE 5F TO 15F RANGE. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 417 AM EDT MON APR 14 2014 LONGWAVE TROUGH AXIS ACROSS THE GREAT LAKES ON TUESDAY. QUITE CHILLY WITHIN THE TROUGH WITH H85 TEMPS DOWN TO -20C OVER LK SUPERIOR. SHORTWAVE DROPPING SE IN THE MEAN TROUGH INCREASES DEPTH OF QUALITY OF MOISTURE AND ALSO STEEPENS H9-H7 LAPSE RATES ON TUESDAY. LAKE EFFECT FLURRIES MAY TRANSITION TO DIURNALLY DRIVEN SNOW SHOWERS WITH COVERAGE EXTENDING INLAND TOWARD WI BORDER AND LK MICHIGAN SHORE. POPS LOW CHANCE AT BEST THOUGH. TEMPS WILL BE VERY COOL FOR THIS TIME OF YEAR WITH READINGS IN THE LOW-MID 20S NORTH AND AROUND 30 IN THE SOUTHERN CWA. NORMAL HIGHS ARE INTO THE LOWER 50S OVER THE SOUTH. WAVE MOVES EAST ON TUESDAY EVENING WHICH SHOULD ALLOW SKIES TO TEMPORARILY CLEAR OUT AHEAD OF NEXT SYSTEM THAT BEGINS TO IMPACT FAR WEST CWA WITH LGT SNOW LATE TUESDAY NIGHT. MIN TEMPS MAY DIP INTO SINGLE DIGITS FOR MANY AREAS BEFORE THICKER CLOUDS MOVE BACK IN LATER DURING THE NIGHT. WHAT TO DO WITH SYSTEM FOR WEDNESDAY WILL BECOME LARGER FOCUS ONCE WE GET PAST SYSTEM BRINGING SNOW TO MUCH OF UPR MICHIGAN TODAY. WILL TWO CAMPS STILL PRESENT IN THE MODELS. NAM/GFS BRING SHORTWAVE AND SFC LOW PRESSURE AND INVERTED TROUGH ACROSS UPPER MISSISSIPPI RIVER VALLEY QUICKER...AND HAVE MORE QPF. BOTH CAMPS OF MODELS GENERATE QPF INTO WESTERN CWA BY 12Z WEDNESDAY...SUPPORTED BY LARGER SCALE DIFFLUENCE ALOFT BTWN JETS EMERGING FM THE PLAINS AND CROSSING LK SUPERIOR REGION. ECMWF AND GEM-NH AND UKMET ARE SLOWER AND NOT AS HEAVY WITH QPF OVER UPR MICHIGAN...KEEPING FOCUS FOR HEAVIER PRECIP OVER CNTRL MN INTO WCNTRL WI ALONG TRACK OF SFC LOW PRESSURE WAVE THROUGH MUCH OF WEDNESDAY BEFORE LIFTING IT ACROSS MAINLY WESTERN HALF OF UPR MICHIGAN LATER WEDNESDAY INTO WEDNESDAY NIGHT. DESPITE MODEL DIFFERENCES...ENOUGH EVIDENCE TO PUSH POPS TO LIKELY WEDNESDAY AND WEDNESDAY NIGHT. ALSO THERE IS DECENT AGREEMENT THAT WESTERN AND PROBABLY CENTRAL CWA WILL SEE MODERATE SNOW AMOUNTS FROM THIS SYSTEM...WITH BULK OF SNOW FALLING WEDNESDAY AFTN THROUGH EARLY THURSDAY MORNING. MIXING RATIOS 2.5-3G/KG WOULD SUPPORT MODERATE SNOW AMOUNTS OF 3 TO 6 INCHES OVER 12 HOUR PERIOD. MODELS SHOWING AREA OF MID-LEVEL FGEN...FAIRLY STRONG CONSIDERING HOW FAR OUT WE ARE STILL...THAT COULD RESULT IN BANDS OF HEAVIER SNOW OVER LIKELY THE WEST CWA. HPC HEAVY SNOW GRAPHICS SHOW MUCH OF FAVORED AREA WITH MODERATE PROBABILITY OF SEEING 4 INCHES OF SNOW WITH LOW PROBABILITY OF SEEING 8 INCHES. BASED ON 1000-850MB AND 850-700MB THICKNESSES AND H85 TEMPS...SNOW WILL MIX WITH AND COULD CHANGE TO RAIN LATER WEDNESDAY NIGHT OVER SCNTRL AND EAST CWA. RAIN/SNOW MIX CONTINUES INTO THURSDAY FOR THOSE AREAS WHILE WIDESPREAD SNOW DIMINISHES ELSEWHERE. NO WATCH ATTM...AS IT WOULD BE LATER 5TH PERIOD AND STILL NEED TO GET THROUGH THIS ONGOING SNOW SYSTEM TO AVOID ANY CONFUSION. WILL CONTINUE TO MENTION IN EHWO/HWOMQT. LATER THURSDAY AND ON INTO NEXT WEEKEND THE FORECAST IS AT BEST MUDDLED...WHICH LEADS TO LOWER THAN AVERAGE CONFIDENCE FOR SURE. GFS MORE OR LESS IS FAIRLY CONSISTENT IN SHOWING SHORTWAVE IN SOUTHERN STREAM LIFTING ACROSS UPPER GREAT LAKES WHILE PHASING WITH NORTHERN BRANCH SHORTWAVE TROUGH. RESULT IS WRAPPED UP SFC LOW WITH WIDESPREAD RAIN AND SNOW OVER UPR MICHIGAN. GEM-NH SUPPORTS IDEA SOMEWHAT THOUGH IT IS SLOWER AND NOT AS STRONG. ECMWF WAS TRENDING NORTH AND WEST WITH THAT SYSTEM...BUT WITH LATEST RUN NOW HAS WENT BACK TO THE SOUTHEAST...KEEPING MUCH OF UPR MICHIGAN DRY ON FRIDAY. ECMWF IS NOT PHASING THE SOUTHERN WAVE NEAR AS MUCH AS GFS ATTEMPTS TO SHOW. CONSENSUS POPS...CAPPED AT LOW CHANCE...WILL BE UTILIZED FOR NOW. WHATEVER LOW PRESSURE SYSTEM WOULD BE EXITING TO START THE WEEKEND...WITH HIGH PRESSURE AND DRIER WEATHER FOR THE REST OF THE WEEKEND AS SHOWN BY GFS. NOT SO INDICATES THE ECMWF...WITH A QUICK PUSH OF NEXT SHORTWAVE ENERGY AND SFC TROUGH/RAIN SHOWERS FOR SUNDAY. LATEST RUN BACKED OFF SOME...BUT JUST SHOWS THE HIGH VARIABILITY THAT CURRENTLY EXISTS FOR THAT FORECAST TIME FRAME. ONE PRETTY SURE THING IS IT LOOKS LIKE WARMING TREND /TEMPS TRYING TO RETURN TOWARD AVERAGE/ DEVELOPS NEXT WEEKEND AFTER WHAT APPEARS TO BE A CHILLY MID APRIL WEEK. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 750 AM EDT MON APR 14 2014 SAW...A LOW PRES MOVING THROUGH NRN LOWER MI THIS MORNING WILL KEEP MODERATE SNOW GOING AT SAW THROUGH MID MORNING. STRONG NRLY UPSLOPE WINDS TO 30 KNOTS WILL ALSO CONTINUE PRODUCING BLOWING DRIFTING SNOW. LIFR CONDITIONS WILL GRADUALLY IMRPROVE TO MVFR BY MIDDAY AS THE ARRIVAL OF DRIER AIR...DAYTIME HEATING AND SLOWLY WEAKENING PRES GRADIENT/WINDS ARRIVE. MVFR CONDITIONS WILL PREDOMINATE THROUGH THE REST OF THE FCST PERIOD. IWD/CMX...SNOW ASSOCIATED WITH THE LOW PRES SYSTEM WILL REMAIN TO THE EAST. BUT WITH A FAVORABLE UPSLOPE N WIND AT IWD...MVFR CIGS SHOULD PREDOMINATE AT THAT LOCATION. BEST CHC FOR SOME IMPROVEMENT TO VFR WILL BE THIS AFTERNOON...WHEN DAYTIME HEATING MIGHT LIFT THE CLOUD BASE INTO THE VFR RANGE. BY LATE THIS EVENING...VFR CONDITIONS WILL BE MORE LIKELY AS HIGH PRES BUILDS IN FROM THE WEST. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 417 AM EDT MON APR 14 2014 NORTH GALES 35-40 KNOTS FOR TODAY...MAINLY EAST HALF...AS LOW PRESSURE SYSTEM TRACKS ACROSS LOWER MICHIGAN THIS MORNING AND EVENTUALLY ACROSS QUEBEC BY THIS EVENING. WINDS QUICKLY DIMINISH BY THIS EVENING AND SHOULD REMAIN BLO 20 KTS OVER MOST OF THE LAKE THROUGH TUESDAY. LOW PRESSURE SYSTEM LIFTING ACROSS UPPER GREAT LAKES LATER ON WEDNESDAY WILL RESULT IN EAST TO NORTHEAST WINDS UP TO 25 KTS OVER MAINLY WESTERN LAKE INTO THURSDAY. WINDS DIMINISH TO LESS THAN 20 KTS REST OF THE FORECAST PERIOD. && .HYDROLOGY... ISSUED AT 417 AM EDT MON APR 14 2014 REPORTS OF ICE JAMS IN DELTA COUNTY SUNDAY ON ESCANABA RIVER AND ASSOCIATED TRIBUTARIES. HYDROLOGIC STATEMENT WAS ISSUED SUNDAY EVENING AND THIS IS VALID THROUGH THIS EVENING. PRECIPITATION OCCURS MAINLY IN THE FORM OF SNOW TODAY. OPPORTUNITIES FOR WIDESPREAD PRECIPITATION ALSO IN THE FORECAST FOR WEDNESDAY THROUGH THURSDAY... AND POSSIBLY FRIDAY. FEASIBLE THAT TOTAL PRECIPITATION FOR THIS WEEK MAY EXCEED AN INCH IN SOME AREAS OF UPPER MICHIGAN. THIS PRECIP ADDED TO EXISTING SNOWPACK WITH WATER EQUIVALENT OF 4-9 INCHES OVER MAINLY WESTERN UPPER MICHIGAN WILL RESULT IN ANOTHER PERIOD OF SNOWMELT AND RUNOFF ONCE WARMER TEMPERATURES MOVE BACK INTO THE REGION BY NEXT WEEKEND. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... WINTER WEATHER ADVISORY UNTIL 7 AM CDT THIS MORNING FOR MIZ010- 011. WINTER WEATHER ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR MIZ007- 013-014-085. WINTER WEATHER ADVISORY UNTIL 10 AM CDT THIS MORNING FOR MIZ012. WINTER STORM WARNING UNTIL 11 AM EDT THIS MORNING FOR MIZ005-006. LAKE SUPERIOR... GALE WARNING UNTIL 5 PM EDT THIS AFTERNOON FOR LSZ249>251-266- 267. GALE WARNING UNTIL 2 PM EDT THIS AFTERNOON FOR LSZ244-245-264- 265. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...JLA AVIATION...JLB MARINE...JLA HYDROLOGY...JLA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
535 AM EDT MON APR 14 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 533 AM EDT MON APR 14 2014 WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL RIDGE OVER THE WEST COAST AND A DOWNSTREAM TROUGH FROM HUDSON BAY THE NRN AND CNTRL PLAINS. A POTENT WELL DEFINED SHORTWAVE TROUGH WITH COMMA RADAR SIGNATURE WAS LIFTING NORTHEAST INTO SW WI. THE COMBINATION OF UPPER LEVEL DIV WITH THE RIGHT ENTRANCE OF THE 140-150 KNOT 300 MB JET OVER NRN ONTARIO...STRONG QVECTOR CONV AND 700-500 MB FGEN SUPPORTED MODERATE TO HEAVY SNOW FROM N CNTRL WI THROUGH CNTRL UPPER MI. RADAR INDICATED THE HIGHER REFLECTIVITY ALIGNED WITH THE MAX FGEN FROM NEAR IMT TO SE MARQUETTE COUNTY. TWO TO THREE INCHES HAD FALLEN IN MANY LOCATIONS OF CNTRL UPPER MI BY 09Z WITH ONE INCH TO THE SE AT ISQ. GIVEN THE WET HEAVY NATURE OF THE SNOW...SLR VALUES WERE LOW...GENERALLY AT OR BELOW 10/1. TODAY...AS THE SHORTWAVE LIFTS TO THE NORTHEAST...EXPECT THE SNOW TO GRADUALLY DIMINISH THIS MORNING AROUND 15Z. ADDITIONAL ACCUMULATIONS OF 2 TO 3 INCHES WOULD BRING TOTALS INTO THE 3 TO 6 INCH RANGE. THE STRONG UPSLOPE NRLY FLOW WILL ALSO HELP BOOST SNOW AMOUNTS TOWARD THE HIGHER END OF THE RANGE OVER THE HIGHER TERRAIN OF N CNTRL UPPER MI. ALTHOUGH WINDS GUSTING TO 35 MPH WILL ALSO PRODUCE BLOWING SNOW...THE SNOW WAS WET ENOUGH SO THAT VSBYS WERE MAINLY ABOVE 1/2SM. SOME LOCALIZED LOWER VSBY WOULD BE EXPECTED NEAR THE LAKE SUPERIOR SHORELINE. AS THE STRONGER DYNAMICS LIFT OUT BY THIS AFTERNOON SOME LIGHT SNOW WILL CONTINUE INTO THE NORTH AS 850 MB TEMPS DROPPING TO AROUND -16C AND SOME LIMITED OPEN WATER PROVIDES ENOUGH HEAT/MOISTURE FOR ADDITIONAL LAKE EFFECT AND OROGRAPHIC SNOW FOR HIGHER TERRAIN LOCATIONS. TONIGHT...ANY LINGERING LAKE EFFECT SNOW WILL DIMINISH BUT COULD STILL PRODUCE A DUSTING OVER THE NORTH. MUCH COLDER AIR WILL MOVE IN WITH MIN READINGS INTO THE 5F TO 15F RANGE. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 417 AM EDT MON APR 14 2014 LONGWAVE TROUGH AXIS ACROSS THE GREAT LAKES ON TUESDAY. QUITE CHILLY WITHIN THE TROUGH WITH H85 TEMPS DOWN TO -20C OVER LK SUPERIOR. SHORTWAVE DROPPING SE IN THE MEAN TROUGH INCREASES DEPTH OF QUALITY OF MOISTURE AND ALSO STEEPENS H9-H7 LAPSE RATES ON TUESDAY. LAKE EFFECT FLURRIES MAY TRANSITION TO DIURNALLY DRIVEN SNOW SHOWERS WITH COVERAGE EXTENDING INLAND TOWARD WI BORDER AND LK MICHIGAN SHORE. POPS LOW CHANCE AT BEST THOUGH. TEMPS WILL BE VERY COOL FOR THIS TIME OF YEAR WITH READINGS IN THE LOW-MID 20S NORTH AND AROUND 30 IN THE SOUTHERN CWA. NORMAL HIGHS ARE INTO THE LOWER 50S OVER THE SOUTH. WAVE MOVES EAST ON TUESDAY EVENING WHICH SHOULD ALLOW SKIES TO TEMPORARILY CLEAR OUT AHEAD OF NEXT SYSTEM THAT BEGINS TO IMPACT FAR WEST CWA WITH LGT SNOW LATE TUESDAY NIGHT. MIN TEMPS MAY DIP INTO SINGLE DIGITS FOR MANY AREAS BEFORE THICKER CLOUDS MOVE BACK IN LATER DURING THE NIGHT. WHAT TO DO WITH SYSTEM FOR WEDNESDAY WILL BECOME LARGER FOCUS ONCE WE GET PAST SYSTEM BRINGING SNOW TO MUCH OF UPR MICHIGAN TODAY. WILL TWO CAMPS STILL PRESENT IN THE MODELS. NAM/GFS BRING SHORTWAVE AND SFC LOW PRESSURE AND INVERTED TROUGH ACROSS UPPER MISSISSIPPI RIVER VALLEY QUICKER...AND HAVE MORE QPF. BOTH CAMPS OF MODELS GENERATE QPF INTO WESTERN CWA BY 12Z WEDNESDAY...SUPPORTED BY LARGER SCALE DIFFLUENCE ALOFT BTWN JETS EMERGING FM THE PLAINS AND CROSSING LK SUPERIOR REGION. ECMWF AND GEM-NH AND UKMET ARE SLOWER AND NOT AS HEAVY WITH QPF OVER UPR MICHIGAN...KEEPING FOCUS FOR HEAVIER PRECIP OVER CNTRL MN INTO WCNTRL WI ALONG TRACK OF SFC LOW PRESSURE WAVE THROUGH MUCH OF WEDNESDAY BEFORE LIFTING IT ACROSS MAINLY WESTERN HALF OF UPR MICHIGAN LATER WEDNESDAY INTO WEDNESDAY NIGHT. DESPITE MODEL DIFFERENCES...ENOUGH EVIDENCE TO PUSH POPS TO LIKELY WEDNESDAY AND WEDNESDAY NIGHT. ALSO THERE IS DECENT AGREEMENT THAT WESTERN AND PROBABLY CENTRAL CWA WILL SEE MODERATE SNOW AMOUNTS FROM THIS SYSTEM...WITH BULK OF SNOW FALLING WEDNESDAY AFTN THROUGH EARLY THURSDAY MORNING. MIXING RATIOS 2.5-3G/KG WOULD SUPPORT MODERATE SNOW AMOUNTS OF 3 TO 6 INCHES OVER 12 HOUR PERIOD. MODELS SHOWING AREA OF MID-LEVEL FGEN...FAIRLY STRONG CONSIDERING HOW FAR OUT WE ARE STILL...THAT COULD RESULT IN BANDS OF HEAVIER SNOW OVER LIKELY THE WEST CWA. HPC HEAVY SNOW GRAPHICS SHOW MUCH OF FAVORED AREA WITH MODERATE PROBABILITY OF SEEING 4 INCHES OF SNOW WITH LOW PROBABILITY OF SEEING 8 INCHES. BASED ON 1000-850MB AND 850-700MB THICKNESSES AND H85 TEMPS...SNOW WILL MIX WITH AND COULD CHANGE TO RAIN LATER WEDNESDAY NIGHT OVER SCNTRL AND EAST CWA. RAIN/SNOW MIX CONTINUES INTO THURSDAY FOR THOSE AREAS WHILE WIDESPREAD SNOW DIMINISHES ELSEWHERE. NO WATCH ATTM...AS IT WOULD BE LATER 5TH PERIOD AND STILL NEED TO GET THROUGH THIS ONGOING SNOW SYSTEM TO AVOID ANY CONFUSION. WILL CONTINUE TO MENTION IN EHWO/HWOMQT. LATER THURSDAY AND ON INTO NEXT WEEKEND THE FORECAST IS AT BEST MUDDLED...WHICH LEADS TO LOWER THAN AVERAGE CONFIDENCE FOR SURE. GFS MORE OR LESS IS FAIRLY CONSISTENT IN SHOWING SHORTWAVE IN SOUTHERN STREAM LIFTING ACROSS UPPER GREAT LAKES WHILE PHASING WITH NORTHERN BRANCH SHORTWAVE TROUGH. RESULT IS WRAPPED UP SFC LOW WITH WIDESPREAD RAIN AND SNOW OVER UPR MICHIGAN. GEM-NH SUPPORTS IDEA SOMEWHAT THOUGH IT IS SLOWER AND NOT AS STRONG. ECMWF WAS TRENDING NORTH AND WEST WITH THAT SYSTEM...BUT WITH LATEST RUN NOW HAS WENT BACK TO THE SOUTHEAST...KEEPING MUCH OF UPR MICHIGAN DRY ON FRIDAY. ECMWF IS NOT PHASING THE SOUTHERN WAVE NEAR AS MUCH AS GFS ATTEMPTS TO SHOW. CONSENSUS POPS...CAPPED AT LOW CHANCE...WILL BE UTILIZED FOR NOW. WHATEVER LOW PRESSURE SYSTEM WOULD BE EXITING TO START THE WEEKEND...WITH HIGH PRESSURE AND DRIER WEATHER FOR THE REST OF THE WEEKEND AS SHOWN BY GFS. NOT SO INDICATES THE ECMWF...WITH A QUICK PUSH OF NEXT SHORTWAVE ENERGY AND SFC TROUGH/RAIN SHOWERS FOR SUNDAY. LATEST RUN BACKED OFF SOME...BUT JUST SHOWS THE HIGH VARIABILITY THAT CURRENTLY EXISTS FOR THAT FORECAST TIME FRAME. ONE PRETTY SURE THING IS IT LOOKS LIKE WARMING TREND /TEMPS TRYING TO RETURN TOWARD AVERAGE/ DEVELOPS NEXT WEEKEND AFTER WHAT APPEARS TO BE A CHILLY MID APRIL WEEK. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 138 AM EDT MON APR 14 2014 SAW...A LO PRES MOVING FM IOWA THRU NRN LWR MI MON MRNG WL BRING A PERIOD OF SN TO SAW EARLY THIS MRNG. WITH AN INCRSG N UPSLOPE WIND THAT WL GUST AS HI AS 30 KTS AND CONTRIBUTE TO SOME BLSN AS WELL... EXPECT CONDITIONS TO DETERIORATE TO IFR/LIFR FOR AT LEAST SEVERAL HRS THRU 12Z. THE ARRIVAL OF DRIER AIR...DAYTIME HEATING AND SLOWLY WEAKENING PRES GRADIENT/WINDS WL BRING MVFR CONDITIONS AFT SUNRISE ON MON. IWD/CMX...SN ASSOCIATED WITH THE LO PRES MOVING THRU THE LKS LATE TNGT WL MISS THESE LOCATIONS TO THE E. BUT WITH A FVRBL...INCRSG UPSLOPE N WIND AT IWD...MVFR CIGS SHOULD PREDOMINATE AT THAT LOCATION. BEST CHC FOR SOME IMPROVEMENT TO VFR AT IWD WL BE MON AFTN...WHEN DAYTIME HEATING MIGHT LIFT THE CLD BASE INTO THE VFR RANGE. SINCE THIS N WIND IS NOT AS FVRBL FOR CMX AND THE INCOMING LLVL AIRMASS IS ON THE DRY SIDE...THIS SITE WL EXPERIENCE PERIODS OF VFR CIGS. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 417 AM EDT MON APR 14 2014 NORTH GALES 35-40 KNOTS FOR TODAY...MAINLY EAST HALF...AS LOW PRESSURE SYSTEM TRACKS ACROSS LOWER MICHIGAN THIS MORNING AND EVENTUALLY ACROSS QUEBEC BY THIS EVENING. WINDS QUICKLY DIMINISH BY THIS EVENING AND SHOULD REMAIN BLO 20 KTS OVER MOST OF THE LAKE THROUGH TUESDAY. LOW PRESSURE SYSTEM LIFTING ACROSS UPPER GREAT LAKES LATER ON WEDNESDAY WILL RESULT IN EAST TO NORTHEAST WINDS UP TO 25 KTS OVER MAINLY WESTERN LAKE INTO THURSDAY. WINDS DIMINISH TO LESS THAN 20 KTS REST OF THE FORECAST PERIOD. && .HYDROLOGY... ISSUED AT 417 AM EDT MON APR 14 2014 REPORTS OF ICE JAMS IN DELTA COUNTY SUNDAY ON ESCANABA RIVER AND ASSOCIATED TRIBUTARIES. HYDROLOGIC STATEMENT WAS ISSUED SUNDAY EVENING AND THIS IS VALID THROUGH THIS EVENING. PRECIPITATION OCCURS MAINLY IN THE FORM OF SNOW TODAY. OPPORTUNITIES FOR WIDESPREAD PRECIPITATION ALSO IN THE FORECAST FOR WEDNESDAY THROUGH THURSDAY... AND POSSIBLY FRIDAY. FEASIBLE THAT TOTAL PRECIPITATION FOR THIS WEEK MAY EXCEED AN INCH IN SOME AREAS OF UPPER MICHIGAN. THIS PRECIP ADDED TO EXISTING SNOWPACK WITH WATER EQUIVALENT OF 4-9 INCHES OVER MAINLY WESTERN UPPER MICHIGAN WILL RESULT IN ANOTHER PERIOD OF SNOWMELT AND RUNOFF ONCE WARMER TEMPERATURES MOVE BACK INTO THE REGION BY NEXT WEEKEND. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... WINTER WEATHER ADVISORY UNTIL 7 AM CDT THIS MORNING FOR MIZ010- 011. WINTER WEATHER ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR MIZ006- 007-013-014-085. WINTER WEATHER ADVISORY UNTIL 11 AM EDT /10 AM CDT/ THIS MORNING FOR MIZ005-012. LAKE SUPERIOR... GALE WARNING UNTIL 5 PM EDT THIS AFTERNOON FOR LSZ249>251-266- 267. GALE WARNING UNTIL 2 PM EDT THIS AFTERNOON FOR LSZ244-245-264- 265. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...JLA AVIATION...KC MARINE...JLA HYDROLOGY...JLA
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
325 AM EDT MON APR 14 2014 LATEST UPDATE... SYNOPSIS/SHORT TERM/LONG TERM .SYNOPSIS... ISSUED AT 325 AM EDT MON APR 14 2014 A LOW PRESSURE SYSTEM CENTERED NEAR CHICAGO EARLY THIS MORNING WILL CONTINUE TO BRING RAIN SHOWERS TODAY. PRECIPITATION WILL GRADUALLY BECOME MIXED WITH AND CHANGE OVER TO SNOW SHOWERS AS COLDER AIR MOVES IN ON THE BACK SIDE OF A LOW PRESSURE SYSTEM THAT WILL CONTINUE TO TRACK NORTHEAST INTO ONTARIO. IT WILL BE BREEZY TODAY AS WELL. TEMPERATURES WILL BE UNSEASONABLY COLD TUESDAY BEFORE UNDERGOING A MODERATING TREND WEDNESDAY THROUGH THURSDAY. && .SHORT TERM...(TODAY THROUGH WEDNESDAY) ISSUED AT 325 AM EDT MON APR 14 2014 SHOWERS WILL CONTINUE TO LINGER THIS MORNING AS LOW PRESSURE NEAR ORD EARLY THIS MORNING TRACKS NE TO SAGINAW BAY BY 12Z AND FURTHER NE INTO ONTARIO BY MIDDAY. FAIRLY WINDY CONDITIONS ARE ANTICIPATED TODAY AS BRISK NW FLOW CAA OCCURS ON THE BACK SIDE OF THE SYSTEM. GUSTY WINDS ARE ALREADY NOTED OVER NORTH/CENTRAL IL INTO NORTHERN INDIANA. HIGHER RES GUIDANCE SUCH AS THE HRRR SUGGESTS SOME GUSTS MAY BRIEFLY REACH AROUND 40 TO NEAR 45 MPH ALONG I-94 AND ESPECIALLY IN OUR FAR SE FCST AREA TOWARD JXN LATER THIS MORNING. THIS IN ADDITION TO A FEW GUSTS TO AROUND 40 TO 45 MPH RIGHT ALONG THE LAKE MI SHORELINE. OVERALL THOUGH FELT A WIND ADVISORY IS NOT NEEDED TODAY SINCE THE MAJORITY OF OUR AREA WILL NOT SEE GUSTS AS HIGH AS 45 MPH. PCPN WILL GRADUALLY BECOME MIXED WITH THEN CHANGE OVER TO LIGHT SNOW SHOWERS FROM NW TO SE ACROSS OUR FCST AREA TODAY AS THE CAA OCCURS. VERY LITTLE TO NO ACCUMULATION IS EXPECTED TODAY. HOWEVER AS TEMPERATURES CONTINUE TO FALL INTO THE 20S TONIGHT WE DO EXPECT LIGHT ACCUMULATIONS ACROSS MOST OF OUR FCST AREA RANGING FROM A FEW TENTHS OF AN INCH TO LOCALLY AS MUCH AS TWO INCHES. LINGERING LIGHT SNOW SHOWERS TUESDAY MORNING WILL TAPER OFF TO FLURRIES BEFORE ENDING AND IT WILL BE UNSEASONABLY COLD WITH MAX TEMPS ONLY IN THE 30S. HIGH PRESSURE WILL BUILD IN TO PRODUCE FAIR BUT COLD WX TUESDAY NIGHT. FAIR WX WILL CONTINUE WEDNESDAY ALONG WITH MUCH MILDER TEMPS AS FLOW BECOMES SOUTHERLY ON THE BACKSIDE OF THE DEPARTING HIGH. .LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY) ISSUED AT 325 AM EDT MON APR 14 2014 NO BIG STORMS EXPECTED IN THE EXTENDED PERIOD. THERE WILL BE SOME RAIN BUT CONVECTION IS NOT LIKELY SO AMOUNTS SHOULD NOT BE EXCESSIVE. TWO LOW PRESSURE CENTERS WILL BE MOVING THROUGH FROM WEDNESDAY NIGHT INTO SATURDAY NIGHT WITH THE HIGHEST CHANCES FOR RAIN ON FRIDAY NIGHT. MODEL SOUNDINGS SUGGEST RAIN COULD MIX WITH WET SNOW ACROSS THE NORTH WEDNESDAY NIGHT AND AGAIN SATURDAY NIGHT BUT CONDITIONS WERE MARGINAL ENOUGH TO LEAVE OUT OF THE FORECAST. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING) ISSUED AT 744 PM EDT SUN APR 13 2014 IMPACTS WILL INCREASE THROUGH THE NIGHT FOR AVIATORS. IFR LOOKS LIKELY ESPECIALLY KGRR AND KMKG WITH THE HEAVIER RAIN. THUNDERSTORMS WILL BE AROUND AS WELL ESPECIALLY WEST OF KLAN AND KJXN. WINDS WILL INCREASE AND VALUES OVER 30 KTS EXPECTED. A SHARP WIND SHIFT IS EXPECTED MONDAY MORNING INTO THE AFTERNOON. TEMPERATURES WILL TURN COLDER AFTER THE WIND SHIFT. ICING MAY BECOME AN ISSUE MONDAY AFTERNOON. && .HYDROLOGY... ISSUED AT 343 PM EDT SUN APR 13 2014 HAVE MAINTAINED THE FLOOD WATCH FOR THE ORIGINAL AREA. THE HEAVY RAIN HAS FALLEN ACROSS THE WATCH AREA WHICH HAS WORKED OUT WELL. AREAL FLOOD WARNINGS ARE IN PLACE FOR CENTRAL LOWER MICHIGAN OR THE NORTHERN THREE ROWS OF THE GRR FORECAST AREA FROM MUSKEGON...NEWAYGO...MONTCALM AND GRATIOT COUNTIES NORTHWARD. QUITE A FEW RAINFALL TOTALS HAVE BEEN RECEIVED ACROSS CENTRAL LOWER IN EXCESS OF 3 INCHES...WITH THE HIGHEST BEING NEAR THE MASON/OCEANA COUNTY LINE NORTH OF MONTAGUE AT 3.82 INCHES. ANOTHER BATCH OF SHOWERS AND STORMS WILL WORK THROUGH THE AREA BETWEEN ABOUT 600 PM THIS EVENING THROUGH MONDAY MORNING. AN ADDITIONAL 1 TO 2 INCHES OF RAIN IS EXPECTED WITH LOCALLY HIGHER AMOUNTS ACROSS CENTRAL LOWER MI WHERE THEY DO NOT NEED ANY MORE RAIN. THE AREAL FLOOD WARNING WILL LIKELY NEED TO BE EXTENDED AS THE NEXT BATCH OF RAIN WILL RESULT IN ADDITIONAL FLOODING. NUMEROUS RIVER ADVISORIES AND WARNINGS ARE IN PLACE WITH POTENTIALLY MORE TO COME. SEVERAL SITES ARE FORECAST TO MOVE INTO THE MODERATE FLOOD CATEGORY WHICH IS SIGNIFICANT FLOODING. SOME OF THE RAIN TONIGHT MAY BE THE HEAVIEST OF THIS ENTIRE EVENT AS PARAMETERS LIKE PWAT (DEEP MOISTURE) PEAK TONIGHT. THE HEAVIER RAIN WILL COME TO AN END MIDDAY ON MONDAY MIXING WITH AND CHANGING OVER TO SNOW DURING THE AFTERNOON AND OVERNIGHT. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...FLOOD WATCH UNTIL 11 AM EDT THIS MORNING FOR MIZ037>040-043>046- 050>052-056>058-064. LM...NONE. && $$ SYNOPSIS...LAURENS SHORT TERM...LAURENS LONG TERM...OSTUNO AVIATION...MJS HYDROLOGY...DUKE
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
328 PM CDT Mon Apr 14 2014 .SHORT TERM: (Through Late Tonight) Issued at 324 PM CDT Mon Apr 14 2014 Main concerns deal with the band of snow currently extending from near Pittsfield to Rolla as well as the going freeze warning. The band has been reducing visibilities to as low as 1/2 mile with some reports of accumulation on grassy surfaces. It is being caused by mid level frontogenesis ahead of the 500mb trough that will move through the area tonight. The RAP and HRRR does show the frotogenesis weakening as it moves acrosss the CWA, but do think that it will likely maintain itself the next few hours before it weakens by early evening. Have extrapolated the band through CWA through early evening, with little or no accumulation of snow expected given the warm low level and surface temperatures. The precipitation and clouds will clear out quick as subsidence moves in behind the passage of the upper trough. With cold air advection and dry dewpoints, expect temperatures to drop quickly to near MOS temperatures. Going freeze warning looks good and plan no changes to it. Britt .LONG TERM: (Tuesday through Next Monday) Issued at 324 PM CDT Mon Apr 14 2014 (Tuesday through Thursday) Have kept Tuesday into Thursday dry as the area will remain cut off from any notable moisture from the Gulf and the active storm track stays north of the area. While Tuesday night will not be as cold as tonight, most areas will still be in the lower to mid 30s for lows. (Thursday Night-Next Monday) The ECMWF and GFS are now similar with the amplitude and timing of the mid level trough and attendant cold front that will move across the area on Friday. Will continue with the chance of showers on Thursday night and Friday before subsidence works in behind the trough keeping Friday night and Saturday dry. Then confidence begins to wane late in the weekend as they both develop QPF over the area. The GFS is placing more emphasis on an northern stream upper over the Upper Midwest while ECMWF is placing it`s emphasis on a shortwave coming out of the southwest CONUS. Either way, will continue the chance of showers we have going Saturday night into Sunday night. Temperatures during the period look to be near or slightly below normal. Britt && .AVIATION: (For the 18z TAFs through 18z Tuesday Afternoon) Issued at 1208 PM CDT Mon Apr 14 2014 Area of SN continues to move ewd. Have made some slight changes to the prev TAFs based on latest RADAR trends and mdl guidance. Confidence is higher that precip will be all SN at COU/UIN early this afternoon. With ample cloud cover across the region, believe temps will remain cold enuf for all SN at SUS/CPS late this afternoon. However, with some uncertainty and since main focus shud be nw of sites, will leave precip as a RA/SN mix for now. Beyond precip, cigs shud lift quickly and remain VFR thru the remainder of the TAF period. Specifics for KSTL: With clouds expected to remain in place, precip this afternoon has a better chance of being SN. However, with placement of precip wrt the terminal, precip may remain as a very light RA or more likely DZ. Beyond precip this afternoon, cigs shud lift quickly to VFR and remain VFR thru the remainder of the TAF period. Tilly && .LSX WATCHES/WARNINGS/ADVISORIES: MO...FREEZE WARNING from 11 PM this evening to 9 AM CDT Tuesday FOR Audrain MO-Boone MO-Callaway MO-Cole MO-Crawford MO- Franklin MO-Gasconade MO-Iron MO-Jefferson MO-Knox MO-Lewis MO-Lincoln MO-Madison MO-Marion MO-Moniteau MO-Monroe MO- Montgomery MO-Osage MO-Pike MO-Ralls MO-Reynolds MO-Shelby MO-St. Charles MO-St. Francois MO-St. Louis City MO-St. Louis MO-Ste. Genevieve MO-Warren MO-Washington MO. IL...FREEZE WARNING from 11 PM this evening to 9 AM CDT Tuesday FOR Adams IL-Bond IL-Brown IL-Calhoun IL-Clinton IL-Fayette IL- Greene IL-Jersey IL-Macoupin IL-Madison IL-Marion IL-Monroe IL-Montgomery IL-Pike IL-Randolph IL-St. Clair IL- Washington IL. && $$ WFO LSX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1115 PM CDT Sun Apr 13 2014 .UPDATE: Issued at 903 PM CDT Sun Apr 13 2014 Two areas of SHRA/TSRA of interest at the moment. The first area moved thru southeast MO and into STL Metro earlier this evening and has dropped up to 1.25" of rain in spots with many areas receiving between 0.3 and 0.75" in the main area of effect. No severe weather is anticipated here with the atmosphere worked over well and not that unstable. Some elevated instability, though, has produced imbedded thunder. The other area is a squall line that had developed over western MO and eastern KS this afternoon and has progressed steadily eastward, but has thus far produced wind gusts up to 50mph. Severe thunderstorm watch #75 continues for a reduced area in east- central MO until midnight CDT, but anticipate this watch being cancelled probably around 10-1030pm given current trends and timing of progression of thunderstorm line. All of this will exit STL metro during the early overnight and late tonight in southwest IL. The next round of more stratiform frontogenetical pcpn is not anticipated until mid-late Monday morning in central MO, expanding elsewhere later on Monday. It is with this area of pcpn, and behind an increasingly chilly airmass, that some snow will be possible, but it remains doubtful on ability to accumulate considering warm ground and surface temps above freezing throughout. Nevertheless, the mere presence of falling snow in mid-April rather unusual in these parts. TES && .SHORT TERM: (Through Late Tonight) Issued at 359 PM CDT Sun Apr 13 2014 (Tonight-Monday Night) Main question tonight will be severe weather chances. Large area of stratiform rain currently over the CWA may suppress these chances as latest SPC objective MUCAPE analysis is mostly below 500 j/kg except across northern Missouri and west central Illinois. The latest runs of the HRRR has been trending toward weaker storms these evening because weaker instability. However, if the rain can mover out of the area, there are very steep lapse rates over the Central Plains that could help quickly destabilize the atmosphere ahead of the line of the storms currently over eastern Kansas. Deep layer shear between 00-03Z will be between 35-50kts which will be sufficient for organized severe storms. Otherwise, forecast did not require too much changes as I still expect front to march southeast across the CWA tonight. Thunderstorm threat will end with the front and change to a plain cold rain. Have kept likely chances to for rain on Monday as the ECMWF/GFS/NAM all mid-level frontogenesis moving across the region during the day. Also added likely chances over the eastern counties on Monday evening as ascent from the mid level trough will not clear the CWA until overnight Monday night. Forecast soundings and critical thicknesses still point to snow mixing with the rain from northwest to southeast during the day on Monday. Do not have any accumulating snow at the moment as the low atmosphere will be rather warm during the day, as will the surface temperatures after this unseasonably warm weekend. With the much colder air moving into the area, temperatures will fall below freezing over the entire CWA on Monday night. Many areas will see temperatures in the mid to upper 20s. Britt .LONG TERM: (Monday through Next Sunday) Issued at 359 PM CDT Sun Apr 13 2014 (Tuesday-Sunday) Upper trough will move east of the area by Tuesday bringing dry weather for mid week. While Monday night looks like the coldest, Tuesday night will likely still have temperatures around freezing before lows become more seasonable later in the week. While the ECMWF has trended deeper and consequently slower with the trough that will move through the central CONUS late this week, it is still not as deep as the GFS or the Canadian GEM. Will stick with the more consistent ECMWF as the GFS is quicker to move the front through the area on Thursday night than it was before. Will keep Thursday dry with the front staying to the northwest most of the day with a chance of showers Thursday night and Friday as the front moves across the area. By next weekend, winds turn out of the southwest quickly behind a retreating high allowing gulf moisture to move north from the Gulf quickly into the area. Britt && .AVIATION: (For the 06z TAFs through 06z Monday Night) Issued at 1028 PM CDT Sun Apr 13 2014 Cold front extending from a surface low over northwestern IL southwest through UIN and COU will move sewd through the St Louis metro area just after 06z Monday. The more significant showers and storms will shift east of the taf sites by 06z Monday, but there may be lingering patchy light rain or isolated light showers til around 08z Monday. Surface winds will veer around to a nwly direction after fropa, and will be relatively strong and gusty late tonight and Monday due to a tight surface pressure gradient. The wind will gradually diminish Monday night as a surface ridge approaches and the surface pressure gradient relaxes. Ceilings will likely fall into the IFR catagory behind this front, down to around 1000 ft or slightly lower late tonight and early Monday morning. The cloud ceiling will gradually rise Monday afternoon, becoming VFR Monday evening. There will be some light rain mainly Monday afternoon as an upper level disturbance moves through the area, possibly mixing with or changing to light snow in UIN and COU as colder air continues to filter sewd into the area. Specifics for KSTL: The cold front will move southeastward through STL just after 06z Monday. The more significant showers and storms will shift east of STL by 06z Monday, but there may be lingering post frontal patchy light rain or isolated light showers until around 08z Monday. The surface wind will veer around to a nwly direction late tonight after fropa. The wind will remain strong and gusty through Monday, then diminish Monday night. The cloud ceiling will lower into the IFR catagory late tonight and early Monday morning after fropa. The cloud ceiling will gradually rise into the MVFR catagory Monday afternoon, VFR Monday evening, then finally clearing out completely late Monday night. Periods of light rain can be expected Monday afternoon, possibly changing to a little light rain/snow mix before ending early Monday evening. GKS && .CLIMATE: RECORD LOWS FOR 4/15: STL - 27 IN 1928 COU - 25 IN 1928 UIN - 24 IN 1928 FAM - 24 IN 1928 && .LSX WATCHES/WARNINGS/ADVISORIES: MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
122 PM CDT MON APR 14 2014 .UPDATE... ISSUED AT 630 AM CDT MON APR 14 2014 THERE IS A WEAK DISTURBANCE IN THE NORTHWEST FLOW CURRENTLY MOVING DOWN ACROSS THE DAKOTAS. THIS FEATURE SHOULD BRING AT LEAST A CHANCE FOR SOME LIGHT PCPN...PROBABLY SPRINKLES OR FLURRIES...THIS AFTERNOON TO PARTS OF EASTERN NEBRASKA. RECENT RUNS OF THE RAP AND HRRR MODELS SHOW THAT TREND...AND THESE MAY EVEN LINGER INTO EARLY EVENING. LOOK FOR HIGHS MAINLY FROM AROUND 40 UP TO THE LOWER AND POSSIBLY MID 40S. && .SHORT TERM...(TODAY THROUGH WEDNESDAY) ISSUED AT 306 AM CDT MON APR 14 2014 STLT IMAGERY THIS MORNING WAS SHOWING A ANOMALOUS LONGWAVE TROF SITUATED OVER THE CNTRL U.S. WITH POTENT VORT MAX JUST EAST OF THE 4 CORNERS REGION. UPSTREAM THEN...HIGHLY AMPLIFIED RIDGE WAS SITUATED OVER THE WRN CONUS/WRN CANADA. AT THE SFC...DEEP LOW PRESSURE WAS CENTERED OVER NRN IL WITH LEADING EDGE OF ATTENDANT COLD FRONT PUSHING DEEP INTO THE SRN PLAINS STATES. OTHERWISE AREA OF -SN HAS FINALLY PUSHED OUT OF ERN NEB AND INTO SWRN IA. EXPECT ACTIVITY TO TAPER OFF THOUGH BY MID MORNING. MODELS ARE IN GOOD AGREEMENT MEAN TROF WILL PREVAIL OVER THE CONUS THRU THE NEAR TERM PDS WITH NEXT SHOT FOR PCPN COMING WED/WED NIGHT WHEN NEXT PAC NW SHORTWAVE MOVES ACROSS THE NRN/CNTRL PLAINS. UNTIL THEN...TEMPS ARE THE MAIN ISSUE TO CONTEND WITH. DEEP TROF ALOFT AND ASSOCIATED COLD AIR ADVECTION HAS RESULTED IN AN IMPRESSIVE TEMP SWING OVER THE REGIONS OVER THE LAST 24HRS...AND AT THIS POINT COLD AIRMASS EXPECTED TO HANG IN TIGHT AT LEAST THRU TONIGHT. COLD THEN TODAY WITH TEMPS STRUGGLING TO REACH THE LOWER 40S. FURTHERMORE... GUSTY NW WINDS/COLD WIND CHILL INDICES WILL ENSURE LOUSY CONDITIONS THRU THE DAY. AS FOR HIGHS TUE/WED...MODERATE REBOUND ADVERTISED BUT STILL JUST BELOW NORM. .LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY) ISSUED AT 306 AM CDT MON APR 14 2014 WED AFTN/NIGHT NEXT ROUND OF PCPN WILL BE POSSIBLE IN ASSOCIATION WITH NEXT COLD FRONT SWEEPING INTO THE CNTRL PLAINS. MODELS IN GOOD AGREEMENT ADVERTISING DEEP LYR QG FORCING WILL BE IN PLACE AT TIME OF FROPA. PCPN TYPE INITIALLY RA...THEN POSSIBLE RA/SN MIX WED NIGHT/THUR MORNING WHEN BRUNT OF CAA ARRIVES. FOCUS FOR PCPN WILL GRADUALLY SHIFT EAST THRU FRIDAY AS BEST DYNAMIC FORCING EXITS THE REGION. SAT NIGHT/SUN...ECM IS MORE AGGRESSIVE WITH QPF OVER SRN NEB/ERN KS IN RELATION TO 295K UPGLIDE/LOW COND PRES DEF. GOING FCST ALREADY HAS THIS COVERED WITH SMALL POPS IN PLACE. OTHERWISE... WARMING TREND ON TAP THRU THE EXTENDED PD WITH LOW 70S ARRIVING EARLY NEXT WEEK. && .AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 115 PM CDT MON APR 14 2014 A WEAK DISTURBANCE DROPPING SE INTO NCNTRL NEBR AT 18Z WILL SPREAD CUMULUS CLOUDS ACROSS TAF SITES THROUGH LATE AFTN/EARLY EVENING WITH OCCASIONAL CIGS GENERALLY ABOVE FL040. A FEW SNOW SHOWERS COULD ACCOMPANY THE CIGS...ESPECIALLY AT KOFK. A PERIOD OF LIGHTER WINDS COULD PRECEDE DISTURBANCE FOLLOWED BY INCREASING WINDS AGAIN LATER THIS AFTN THROUGH SUNSET BEFORE WINDS DECREASE AGAIN. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ UPDATE...MILLER SHORT TERM...DEE LONG TERM...DEE AVIATION...CHERMOK
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1239 PM CDT MON APR 14 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 345 AM CDT MON APR 14 2014 A WEAK UPPER LEVEL DISTURBANCE...CURRENTLY ACROSS ERN MT/WRN ND... WILL DROP SOUTH THROUGH THE FCST AREA TODAY. LAPSE RATES FROM 850-700MB ARE STEEP AND MOIST BUT THE 850MB-SFC LAYER IS VERY DRY WITH DEW POINTS IN THE TEENS AND LOWER 20S. WHILE TEMPERATURE RISE IN THE LOW TO MID 40S THIS AFTN...WET BULB ZERO HEIGHTS WITH BE CLOSE TO THE GROUND AND THE HRRR AND RAP SHOW SNOW FOR THE PTYPE. SO ISOLATED SNOW SHOWERS ARE IN THE FORECAST. NO MEASURABLE QPF WAS INDICATED IN THE RAP SOLN BUT THE HRRR ACTUALLY SHOWS SCATTERED SNOW SHOWERS WITH SEVERAL STREAKS OF 0.01 QPF AND THE MODEL CONSENSUS INDICATES H700MB AROUND -18C AT KVTN WHICH IS VERY IMPRESSIVE FOR MID APRIL. THIS DISTURBANCE WILL DRAW ANOTHER WEAK PIECE OF ARCTIC HIGH PRESSURE INTO THE ERN HALF OF THE FORECAST AREA TONIGHT WHILE THE WRN HALF DEVELOPS SOUTH WINDS AS LOW PRESSURE FORMS ACROSS THE NRN HIGH PLAINS. LOWS TONIGHT SHOULD FALL INTO THE LOW TO MID 20S WITH GENERALLY CLEAR SKIES. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 345 AM CDT MON APR 14 2014 WARM AIR QUICKLY SPREADS NORTHEAST INTO THE REGION TUESDAY...WITH H85 TEMPS RISING TO 8C TO 12C BY AFTERNOON. THIS SHOULD YIELD HIGHS IN THE UPPER 50S TO MID 60S. HAVE RAISED LOWS TUESDAY NIGHT...AS SOUTHERLY LOW LEVEL JET KEEPS ATMOSPHERE MIXED AND H85 TEMPS CONTINUE TO WARM...NEARING 13C. SHORTWAVE ENERGY DIVES SOUTHEAST INTO THE PLAINS LATE WEDNESDAY THROUGH THURSDAY. MODELS CONTINUE TO MOVE THIS THROUGH QUICKLY AS AN OPEN WAVE...WITH THE BEST UPPER LEVEL DYNAMICS CROSSING THROUGH NORTHERN KANSAS. WILL CONTINUE THE HIGHEST POPS /NEAR 40 PERCENT/ ACROSS FAR SOUTHERN NEBRASKA. SOUNDING PROFILES INDICATE A MIX OF RAIN AND SNOW OR WET SNOW...BUT NOT EXPECTING MUCH QPF AT THIS POINT. CHILLY WEATHER IN THE WAKE OF THE SYSTEM THURSDAY...AS MORE ARCTIC AIR MOVES SOUTH INTO THE PLAINS. AS WE HEAD INTO NEXT WEEKEND...THE GFS AND ECMWF ARE BOTH ADVERTISING UPPER LEVEL ENERGY ADVANCING EASTWARD FROM THE PACIFIC INTO THE SOUTHWEST CONUS. THIS AIDS IN THE DEVELOPMENT OF A SURFACE TROUGH ALONG THE HIGH PLAINS...WITH SOUTHERLY FLOW EAST OF THE TROUGH DRAWING GULF MOISTURE NORTHWARD INTO THE PLAINS. IT WOULD APPEAR THAT SOME TSTM ACTIVITY IS POSSIBLE SATURDAY NIGHT ON THE NOSE OF A SOUTHERLY LOW LEVEL JET...AND THEN PERHAPS SUNDAY AS A COLD FRONT AND LOW PRESSURE SYSTEM ADVANCE EAST ACROSS THE AREA. ALTHOUGH BOTH MODELS DRAW MOISTURE NORTH INTO THE PLAINS...THERE ARE DIFFERENCES IN THE HANDLING OF THE UPPER LEVEL ENERGY ACROSS THE SOUTHWEST CONUS. WILL LEAVE THE FORECAST DRY AT THIS TIME...AS THE MODELS SEEM TO BE JUST STARTING TO LATCH ONTO THIS SCENARIO. IF THIS CONTINUES TO BE SHOWN IN FUTURE MODEL RUNS...THEN SOME THUNDER MENTION WILL HAVE TO BE ADDED TO THE WEEKEND FORECAST. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1239 PM CDT MON APR 14 2014 ISOLATED SNOW SHOWERS WILL MOVE NORTHWEST TO SOUTHEAST ACROSS NEBRASKA THIS AFTERNOON. FROM LATEST OBSERVATIONS...LITTLE SNOW IS REACHING THE GROUND FROM THESE SHOWERS...SO VISIBILITY REMAINS VFR. WOULD EXPECT THIS TREND TO CONTINUE THROUGH THE AFTERNOON WITH THESE SHOWERS ALTHOUGH IT IS NOT ENTIRELY OUT OF THE QUESTION TO GET CONDITIONS DETERIORATE FOR A VERY BRIEF TIME WITH LOWERED VISIBILITIES. DID NOT INCLUDE ANY LOWERED CONDITIONS IN THE FORECASTS AS THERE IS LITTLE CONFIDENCE IN ANY IMPACT OCCURRING AT THE TERMINALS. OTHERWISE...WINDS WILL DIMINISH TONIGHT AND PICK UP AGAIN FROM THE SOUTH BY LATE MORNING ON TUESDAY. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...CDC LONG TERM...TAYLOR AVIATION...BROOKS
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
630 AM CDT MON APR 14 2014 .UPDATE... ISSUED AT 630 AM CDT MON APR 14 2014 THERE IS A WEAK DISTURBANCE IN THE NORTHWEST FLOW CURRENTLY MOVING DOWN ACROSS THE DAKOTAS. THIS FEATURE SHOULD BRING AT LEAST A CHANCE FOR SOME LIGHT PCPN...PROBABLY SPRINKLES OR FLURRIES...THIS AFTERNOON TO PARTS OF EASTERN NEBRASKA. RECENT RUNS OF THE RAP AND HRRR MODELS SHOW THAT TREND...AND THESE MAY EVEN LINGER INTO EARLY EVENING. LOOK FOR HIGHS MAINLY FROM AROUND 40 UP TO THE LOWER AND POSSIBLY MID 40S. && .SHORT TERM...(TODAY THROUGH WEDNESDAY) ISSUED AT 306 AM CDT MON APR 14 2014 STLT IMAGERY THIS MORNING WAS SHOWING A ANOMALOUS LONGWAVE TROF SITUATED OVER THE CNTRL U.S. WITH POTENT VORT MAX JUST EAST OF THE 4 CORNERS REGION. UPSTREAM THEN...HIGHLY AMPLIFIED RIDGE WAS SITUATED OVER THE WRN CONUS/WRN CANADA. AT THE SFC...DEEP LOW PRESSURE WAS CENTERED OVER NRN IL WITH LEADING EDGE OF ATTENDANT COLD FRONT PUSHING DEEP INTO THE SRN PLAINS STATES. OTHERWISE AREA OF -SN HAS FINALLY PUSHED OUT OF ERN NEB AND INTO SWRN IA. EXPECT ACTIVITY TO TAPER OFF THOUGH BY MID MORNING. MODELS ARE IN GOOD AGREEMENT MEAN TROF WILL PREVAIL OVER THE CONUS THRU THE NEAR TERM PDS WITH NEXT SHOT FOR PCPN COMING WED/WED NIGHT WHEN NEXT PAC NW SHORTWAVE MOVES ACROSS THE NRN/CNTRL PLAINS. UNTIL THEN...TEMPS ARE THE MAIN ISSUE TO CONTEND WITH. DEEP TROF ALOFT AND ASSOCIATED COLD AIR ADVECTION HAS RESULTED IN AN IMPRESSIVE TEMP SWING OVER THE REGIONS OVER THE LAST 24HRS...AND AT THIS POINT COLD AIRMASS EXPECTED TO HANG IN TIGHT AT LEAST THRU TONIGHT. COLD THEN TODAY WITH TEMPS STRUGGLING TO REACH THE LOWER 40S. FURTHERMORE... GUSTY NW WINDS/COLD WIND CHILL INDICES WILL ENSURE LOUSY CONDITIONS THRU THE DAY. AS FOR HIGHS TUE/WED...MODERATE REBOUND ADVERTISED BUT STILL JUST BELOW NORM. .LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY) ISSUED AT 306 AM CDT MON APR 14 2014 WED AFTN/NIGHT NEXT ROUND OF PCPN WILL BE POSSIBLE IN ASSOCIATION WITH NEXT COLD FRONT SWEEPING INTO THE CNTRL PLAINS. MODELS IN GOOD AGREEMENT ADVERTISING DEEP LYR QG FORCING WILL BE IN PLACE AT TIME OF FROPA. PCPN TYPE INITIALLY RA...THEN POSSIBLE RA/SN MIX WED NIGHT/THUR MORNING WHEN BRUNT OF CAA ARRIVES. FOCUS FOR PCPN WILL GRADUALLY SHIFT EAST THRU FRIDAY AS BEST DYNAMIC FORCING EXITS THE REGION. SAT NIGHT/SUN...ECM IS MORE AGGRESSIVE WITH QPF OVER SRN NEB/ERN KS IN RELATION TO 295K UPGLIDE/LOW COND PRES DEF. GOING FCST ALREADY HAS THIS COVERED WITH SMALL POPS IN PLACE. OTHERWISE... WARMING TREND ON TAP THRU THE EXTENDED PD WITH LOW 70S ARRIVING EARLY NEXT WEEK. && .AVIATION...(12Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 630 AM CDT MON APR 14 2014 LOOK FOR VFR CONDITIONS TO PREVAIL THROUGH THE PERIOD. EXPECT VRBL MID AND HIGH LEVEL CLOUDINESS THIS MORNING...BUT INCREASING CLOUDS IN THE 4000 TO 8000 FOOT LAYER THIS AFTERNOON WITH THE DISTURBANCE MOVING IN FROM THE NORTHWEST. COULD SEE SOME LIGHT SNOW OR LIGHT RAIN (PROBABLY MOSTLY FLURRIES OR SPRINKLES) THIS AFTERNOON MAINLY AT KOFK AND KLNK. THOSE CLOUDS SHOULD THEN DISIPATE THIS EVENING. WINDS WILL ALSO DECREASE THROUGH THE DAY...BECOMING LIGHT TONIGHT. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ UPDATE...MILLER SHORT TERM...DEE LONG TERM...DEE AVIATION...MILLER
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
623 AM CDT MON APR 14 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 345 AM CDT MON APR 14 2014 A WEAK UPPER LEVEL DISTURBANCE...CURRENTLY ACROSS ERN MT/WRN ND... WILL DROP SOUTH THROUGH THE FCST AREA TODAY. LAPSE RATES FROM 850-700MB ARE STEEP AND MOIST BUT THE 850MB-SFC LAYER IS VERY DRY WITH DEW POINTS IN THE TEENS AND LOWER 20S. WHILE TEMPERATURE RISE IN THE LOW TO MID 40S THIS AFTN...WET BULB ZERO HEIGHTS WITH BE CLOSE TO THE GROUND AND THE HRRR AND RAP SHOW SNOW FOR THE PTYPE. SO ISOLATED SNOW SHOWERS ARE IN THE FORECAST. NO MEASURABLE QPF WAS INDICATED IN THE RAP SOLN BUT THE HRRR ACTUALLY SHOWS SCATTERED SNOW SHOWERS WITH SEVERAL STREAKS OF 0.01 QPF AND THE MODEL CONSENSUS INDICATES H700MB AROUND -18C AT KVTN WHICH IS VERY IMPRESSIVE FOR MID APRIL. THIS DISTURBANCE WILL DRAW ANOTHER WEAK PIECE OF ARCTIC HIGH PRESSURE INTO THE ERN HALF OF THE FORECAST AREA TONIGHT WHILE THE WRN HALF DEVELOPS SOUTH WINDS AS LOW PRESSURE FORMS ACROSS THE NRN HIGH PLAINS. LOWS TONIGHT SHOULD FALL INTO THE LOW TO MID 20S WITH GENERALLY CLEAR SKIES. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 345 AM CDT MON APR 14 2014 WARM AIR QUICKLY SPREADS NORTHEAST INTO THE REGION TUESDAY...WITH H85 TEMPS RISING TO 8C TO 12C BY AFTERNOON. THIS SHOULD YIELD HIGHS IN THE UPPER 50S TO MID 60S. HAVE RAISED LOWS TUESDAY NIGHT...AS SOUTHERLY LOW LEVEL JET KEEPS ATMOSPHERE MIXED AND H85 TEMPS CONTINUE TO WARM...NEARING 13C. SHORTWAVE ENERGY DIVES SOUTHEAST INTO THE PLAINS LATE WEDNESDAY THROUGH THURSDAY. MODELS CONTINUE TO MOVE THIS THROUGH QUICKLY AS AN OPEN WAVE...WITH THE BEST UPPER LEVEL DYNAMICS CROSSING THROUGH NORTHERN KANSAS. WILL CONTINUE THE HIGHEST POPS /NEAR 40 PERCENT/ ACROSS FAR SOUTHERN NEBRASKA. SOUNDING PROFILES INDICATE A MIX OF RAIN AND SNOW OR WET SNOW...BUT NOT EXPECTING MUCH QPF AT THIS POINT. CHILLY WEATHER IN THE WAKE OF THE SYSTEM THURSDAY...AS MORE ARCTIC AIR MOVES SOUTH INTO THE PLAINS. AS WE HEAD INTO NEXT WEEKEND...THE GFS AND ECMWF ARE BOTH ADVERTISING UPPER LEVEL ENERGY ADVANCING EASTWARD FROM THE PACIFIC INTO THE SOUTHWEST CONUS. THIS AIDS IN THE DEVELOPMENT OF A SURFACE TROUGH ALONG THE HIGH PLAINS...WITH SOUTHERLY FLOW EAST OF THE TROUGH DRAWING GULF MOISTURE NORTHWARD INTO THE PLAINS. IT WOULD APPEAR THAT SOME TSTM ACTIVITY IS POSSIBLE SATURDAY NIGHT ON THE NOSE OF A SOUTHERLY LOW LEVEL JET...AND THEN PERHAPS SUNDAY AS A COLD FRONT AND LOW PRESSURE SYSTEM ADVANCE EAST ACROSS THE AREA. ALTHOUGH BOTH MODELS DRAW MOISTURE NORTH INTO THE PLAINS...THERE ARE DIFFERENCES IN THE HANDLING OF THE UPPER LEVEL ENERGY ACROSS THE SOUTHWEST CONUS. WILL LEAVE THE FORECAST DRY AT THIS TIME...AS THE MODELS SEEM TO BE JUST STARTING TO LATCH ONTO THIS SCENARIO. IF THIS CONTINUES TO BE SHOWN IN FUTURE MODEL RUNS...THEN SOME THUNDER MENTION WILL HAVE TO BE ADDED TO THE WEEKEND FORECAST. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 620 AM CDT MON APR 14 2014 VFR IS GENERALLY EXPECTED TODAY AND TONIGHT. THE DISTURBANCE ACROSS SD/ND THIS AM MOVES THROUGH NCNTL NEB THIS AFTN SPARKING ISOLATED TO PERHAPS SCATTERED SHSN/MVFR CONDITIONS. THIS SHOULD DISSIPATE BY 00Z WITH VFR ALL AREAS THEREAFTER. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...CDC LONG TERM...TAYLOR AVIATION...CDC
AREA FORECAST DISCUSSION...CORRECTED
NWS NORTH PLATTE NE
359 AM CDT MON APR 14 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 345 AM CDT MON APR 14 2014 A WEAK UPPER LEVEL DISTURBANCE...CURRENTLY ACROSS ERN MT/WRN ND... WILL DROP SOUTH THROUGH THE FCST AREA TODAY. LAPSE RATES FROM 850-700MB ARE STEEP AND MOIST BUT THE 850MB-SFC LAYER IS VERY DRY WITH DEW POINTS IN THE TEENS AND LOWER 20S. WHILE TEMPERATURE RISE IN THE LOW TO MID 40S THIS AFTN...WET BULB ZERO HEIGHTS WITH BE CLOSE TO THE GROUND AND THE HRRR AND RAP SHOW SNOW FOR THE PTYPE. SO ISOLATED SNOW SHOWERS ARE IN THE FORECAST. NO MEASURABLE QPF WAS INDICATED IN THE RAP SOLN BUT THE HRRR ACTUALLY SHOWS SCATTERED SNOW SHOWERS WITH SEVERAL STREAKS OF 0.01 QPF AND THE MODEL CONSENSUS INDICATES H700MB AROUND -18C AT KVTN WHICH IS VERY IMPRESSIVE FOR MID APRIL. THIS DISTURBANCE WILL DRAW ANOTHER WEAK PIECE OF ARCTIC HIGH PRESSURE INTO THE ERN HALF OF THE FORECAST AREA TONIGHT WHILE THE WRN HALF DEVELOPS SOUTH WINDS AS LOW PRESSURE FORMS ACROSS THE NRN HIGH PLAINS. LOWS TONIGHT SHOULD FALL INTO THE LOW TO MID 20S WITH GENERALLY CLEAR SKIES. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 345 AM CDT MON APR 14 2014 WARM AIR QUICKLY SPREADS NORTHEAST INTO THE REGION TUESDAY...WITH H85 TEMPS RISING TO 8C TO 12C BY AFTERNOON. THIS SHOULD YIELD HIGHS IN THE UPPER 50S TO MID 60S. HAVE RAISED LOWS TUESDAY NIGHT...AS SOUTHERLY LOW LEVEL JET KEEPS ATMOSPHERE MIXED AND H85 TEMPS CONTINUE TO WARM...NEARING 13C. SHORTWAVE ENERGY DIVES SOUTHEAST INTO THE PLAINS LATE WEDNESDAY THROUGH THURSDAY. MODELS CONTINUE TO MOVE THIS THROUGH QUICKLY AS AN OPEN WAVE...WITH THE BEST UPPER LEVEL DYNAMICS CROSSING THROUGH NORTHERN KANSAS. WILL CONTINUE THE HIGHEST POPS /NEAR 40 PERCENT/ ACROSS FAR SOUTHERN NEBRASKA. SOUNDING PROFILES INDICATE A MIX OF RAIN AND SNOW OR WET SNOW...BUT NOT EXPECTING MUCH QPF AT THIS POINT. CHILLY WEATHER IN THE WAKE OF THE SYSTEM THURSDAY...AS MORE ARCTIC AIR MOVES SOUTH INTO THE PLAINS. AS WE HEAD INTO NEXT WEEKEND...THE GFS AND ECMWF ARE BOTH ADVERTISING UPPER LEVEL ENERGY ADVANCING EASTWARD FROM THE PACIFIC INTO THE SOUTHWEST CONUS. THIS AIDS IN THE DEVELOPMENT OF A SURFACE TROUGH ALONG THE HIGH PLAINS...WITH SOUTHERLY FLOW EAST OF THE TROUGH DRAWING GULF MOISTURE NORTHWARD INTO THE PLAINS. IT WOULD APPEAR THAT SOME TSTM ACTIVITY IS POSSIBLE SATURDAY NIGHT ON THE NOSE OF A SOUTHERLY LOW LEVEL JET...AND THEN PERHAPS SUNDAY AS A COLD FRONT AND LOW PRESSURE SYSTEM ADVANCE EAST ACROSS THE AREA. ALTHOUGH BOTH MODELS DRAW MOISTURE NORTH INTO THE PLAINS...THERE ARE DIFFERENCES IN THE HANDLING OF THE UPPER LEVEL ENERGY ACROSS THE SOUTHWEST CONUS. WILL LEAVE THE FORECAST DRY AT THIS TIME...AS THE MODELS SEEM TO BE JUST STARTING TO LATCH ONTO THIS SCENARIO. IF THIS CONTINUES TO BE SHOWN IN FUTURE MODEL RUNS...THEN SOME THUNDER MENTION WILL HAVE TO BE ADDED TO THE WEEKEND FORECAST. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1128 PM CDT SUN APR 13 2014 EXPECT MID AND HIGH LEVEL CLOUDINESS TO PERSIST INTO THE OVERNIGHT HOURS...ESPECIALLY AT THE KLBF TERMINAL WHERE CIGS WILL RANGE FROM 9000 TO 12000 FT AGL OVERNIGHT. FOR THE KVTN TERMINAL...SCATTERED HIGH CLOUDINESS AON 25000 FT AGL SHOULD SET IN OVERNIGHT. FOR BOTH TERMINALS...AN UPPER LEVEL TROUGH WILL DIVE SOUTH FROM THE DAKOTAS INTO NEBRASKA ON MONDAY. THIS FEATURE WILL STEEPEN MID LEVEL LAPSE RATES...LEADING TO BROKEN CIGS AROUND 6000 FT AGL LATE MONDAY MORNING INTO THE AFTERNOON HOURS. SKIES WILL CLEAR TOWARD SUNSET MONDAY EVENING. WINDS WILL BE FROM THE NORTH OR NORTHWEST AT 10 TO 20 KTS OVER THE NEXT 24 HOURS. SOME GUSTS MAY APPROACH 25 KTS LATE MONDAY MORNING THROUGH MONDAY AFTERNOON. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...CDC LONG TERM...TAYLOR AVIATION...CLB
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1129 PM CDT SUN APR 13 2014 .UPDATE... ISSUED AT 623 PM CDT SUN APR 13 2014 JUST UPDATED THE FORECAST TO CANCEL THE WINTER WEATHER ADVISORY FROM CUSTER...GARFIELD AND WHEELER COUNTIES. SNOW HAS ENDED IN THESE AREAS...HOWEVER SOME VERY LIGHT SNOW IS POSSIBLE ACROSS THE SOUTHEASTERN NEBRASKA PANHANDLE AND FAR SOUTHWESTERN NEBRASKA THIS EVENING. RADAR RETURNS FROM COLORADO AND FAR SERN WYOMING...INDICATE A NICE AREA OF LIGHT TO MODERATE SNOW IN NERN COLORADO IN ASSOCIATION WITH A TRAILING DISTURBANCE OVER FAR SERN UT. THE LATEST RAP AND NAM SOLNS...ALLOW THIS SNOW TO DRIFT INTO THE FAR SOUTHWESTERN FORECAST AREA THROUGH MID EVENING...THEN SHIFTING IT SOUTH INTO KANSAS BY LATE EVENING. LITTLE OR NO ADDITIONAL ACCUMULATIONS ARE EXPECTED WITH ANY SNOW WHICH MOVES INTO THE FORECAST AREA. && .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 345 PM CDT SUN APR 13 2014 AT 19Z...WATER VAPOR IMAGERY SHOWED A SHORTWAVE TROUGH MOVING ACROSS CENTRAL NEBRASKA/KANSAS WITH A GOOD RIDGE DOWNSTREAM ACROSS THE EASTERN HALF OF THE COUNTRY. LOOKING UPSTREAM...ANOTHER SHORTWAVE TROUGH HAD BEEN DIGGING SOUTH THROUGH THE DAY...FROM THE PACIFIC NORTHWEST DOWN OVER UTAH AT THE CURRENT TIME. THE SHORTWAVE OVER THE LOCAL AREA HAD AN ASSOCIATED SURFACE LOW IN EASTERN KANSAS...WITH A COLD FRONT INTO THE SOUTHERN PLAINS AND A WARM FRONT TO THE NORTHEAST INTO IOWA. COLD AIR ADVECTION WAS ONGOING THROUGH THE DAY...AND AS THE WET BULB TEMPERATURE DROPPED BELOW THE FREEZING MARK BY EARLY TO MID MORNING...MUCH OF THE PRECIPITATION LOCALLY FELL AS SNOW. MID LEVEL FRONTOGENESIS HAD BEEN ONGOING THROUGH THE DAY AS THE 700MB LOW TRACKED JUST SOUTHEAST OF THE FORECAST AREA...FROM NORTHWEST KANSAS INTO SOUTH CENTRAL NEBRASKA. PRECIPITATION DEVELOPED IN THIS AREA. THE FRONTOGENETICAL FORCING HAS SHIFTED EAST THROUGH THE DAY...WHICH ALLOWED THE PRECIPITATION TO ALSO SHIFT EAST THROUGH THE DAY AND BY MID AFTERNOON HAS MOSTLY ENDED. THERE WERE SEVERAL STRONGER BANDS OF SNOW THAT DEVELOPED...WHICH DROPPED AS MUCH AS 5 INCHES OF SNOW IN PARTS OF THE FORECAST AREA. AT 20Z...MODERATE SNOWFALL DID CONTINUE FROM CURTIS TO BROKEN BOW TO ALMERIA...WITH VERY LIGHT SNOW STILL IN AREAS TO THE WEST. THE WINTER WEATHER ADVISORY WILL BE CANCELLED EARLY FOR THOSE LOCATIONS WHERE THE HEAVIER SNOW HAS ENDED AS HAZARDOUS WEATHER CONDITIONS HAVE GENERALLY ENDED. THERE COULD BE A FEW LOCATIONS WHERE ROADWAYS MAY REMAIN SLICK...BUT ANY FOLLOWING WEATHER CONDITIONS WILL NOT MAKE THINGS WORSE. WINDS WILL REMAIN STRONG INTO THE EVENING...BUT WILL START TO SLOWLY DIMINISH AS THE SURFACE LOW CONTINUES TO THE NORTHEAST ALLOWING THE PRESSURE GRADIENT TO SLACKEN. WINDS HAVE LARGELY BEEN JUST BELOW WIND ADVISORY CRITERIA /SUSTAINED OF 30 MPH AND GUSTS OF 45 MPH/ IN THE PAST SEVERAL HOURS. COULD STILL GET A FEW HIGHER READINGS YET THIS AFTERNOON BUT FEEL THIS WOULD BE MORE LOCALIZED SO NO NEED FOR ADDITIONAL WIND HEADLINES. THE SNOW OCCURRING AT THE PRESENT TIME WILL CONTINUE TO SHIFT EAST THROUGH THIS EVENING AND WILL BE MOSTLY OUT OF THE FORECAST AREA BY 00Z. AFTER 00Z...CHANCES FOR PRECIPITATION WILL BE FOCUSED OVER THE SOUTHWEST AS THE UPPER LEVEL SYSTEM OVER UTAH KICKS EAST OVERNIGHT. THAT SYSTEM HAS BEEN TRENDING FURTHER SOUTH OVER THE PAST FEW DAYS...AND 12Z MODEL RUNS ARE FAIRLY CONSISTENT KEEPING PRECIPITATION TONIGHT SOUTH OF THE AREA...ACROSS COLORADO AND KANSAS. DID TREND THE FORECAST DRIER FOR THE EVENING...BUT KEPT SLIGHT CHANCES FOR THE FAR SOUTHWEST IN CASE OF A SLIGHT SHIFT. COLDER AIR WILL STAY IN PLACE AS ANOTHER LOW PRESSURE SYSTEM OUT OF CANADA MOVES INTO THE NORTHERN PLAINS. THIS SYSTEM WILL JUST ENHANCE THE INFLUENCE OF THE COLDER AIR BY KEEPING IT HERE RATHER THAN LETTING IT DRIFT EAST. SKIES ARE EXPECTED TO CLEAR OUT BY MONDAY MORNING...AND WITH THE NEW SNOW...MAY GET SOME RADIATIONAL COOLING TO HELP COOL THE SURFACE OVERNIGHT. LOWS TONIGHT WERE DROPPED SLIGHTLY...WITH LOWS IN THE LOW TO MID 20S LIKELY. THEN FOR MONDAY...THE MODELS ARE SLOW TO MOVE THE COLDER AIRMASS OUT OF THE AREA...AND ALTHOUGH IT IS MID APRIL...THINK THE SNOW MAY HAVE A SLIGHT INFLUENCE SO DID DROP HIGHS A FEW DEGREES FOR MONDAY. NOW LOOKING AT HIGHS IN THE 40S. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 345 PM CDT SUN APR 13 2014 LIGHT SOUTH AND SOUTHWEST WINDS TO DEVELOP MONDAY NIGHT. LOWS WILL BE SUB FREEZING IN THE LOW TO MID 20S AS LOW DEWPOINTS DICTATE STRONG COOLING OVERNIGHT. ON TUESDAY...AN UPSTREAM SHORT WAVE TROUGH DROPS INTO MONTANA AND IDAHO...TEMPERATURES WILL RECOVERY SIGNIFICANTLY INTO THE LOWER 60S AS THERMAL RIDGE BUILDS INTO THE CENTRAL HIGH PLAINS. A COLD FRONT WILL MOVE INTO THE NORTHWEST ZONES TUESDAY NIGHT AS SCATTERED PRECIPITATION MOVES INTO WYOMING AND THE BLACK HILLS REGION. LOWS NOT AS COLD IN THE MID 30S. THEN ON WEDNESDAY...A CHANCE FOR SHOWERS IN NORTH CENTRAL NEBRASKA WITH A COLD FRONT SWEEPING THE REMAINING FA BY 18Z. THE NAM MODEL IS QUITE A BIT WARMER WITH H85 TEMPS 4C TO 6C. WILL GO BETWEEN THE COLDER GFS OF 0C TO -6C. WILL GO NEARER THE NAM SOLUTION WITH MID 50S SOUTHEAST TO THE MID 40S NORTHWEST. ALSO BREEZY NORTHWEST WINDS. LOWERED POPS SLIGHTLY WEDNESDAY NIGHT INTO THURSDAY AS SYSTEM LOOKING TO MATURE ACROSS COLORADO INTO KANSAS AND SERN NEBR. PRECIPITATION TYPE RAIN OR SNOW WEDNESDAY EVENING...SNOW OVERNIGHT INTO THURSDAY MORNING...THEN BACK TO RAIN OR SNOW THURSDAY AFTERNOON. HIGHS THURSDAY CLOSE TO PREVIOUS FORECAST IN THE LOWER 40S. FOR FRIDAY THROUGH SUNDAY...A DAILY WARMING TREND. AN UPPER RIDGE IN THE WESTERN CONUS WILL GRADUALLY BUILD EAST INTO THE ROCKIES BY SUNDAY WITH MUCH MILDER AIR RETURNING TO THE PLAINS. HIGHS IN THE 50S FRIDAY...60S SATURDAY...THEN NEAR 70 SUNDAY. DRY THROUGH THE PERIOD AS WELL. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1128 PM CDT SUN APR 13 2014 EXPECT MID AND HIGH LEVEL CLOUDINESS TO PERSIST INTO THE OVERNIGHT HOURS...ESPECIALLY AT THE KLBF TERMINAL WHERE CIGS WILL RANGE FROM 9000 TO 12000 FT AGL OVERNIGHT. FOR THE KVTN TERMINAL...SCATTERED HIGH CLOUDINESS AON 25000 FT AGL SHOULD SET IN OVERNIGHT. FOR BOTH TERMINALS...AN UPPER LEVEL TROUGH WILL DIVE SOUTH FROM THE DAKOTAS INTO NEBRASKA ON MONDAY. THIS FEATURE WILL STEEPEN MID LEVEL LAPSE RATES...LEADING TO BROKEN CIGS AROUND 6000 FT AGL LATE MONDAY MORNING INTO THE AFTERNOON HOURS. SKIES WILL CLEAR TOWARD SUNSET MONDAY EVENING. WINDS WILL BE FROM THE NORTH OR NORTHWEST AT 10 TO 20 KTS OVER THE NEXT 24 HOURS. SOME GUSTS MAY APPROACH 25 KTS LATE MONDAY MORNING THROUGH MONDAY AFTERNOON. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...CLB SHORT TERM...BROOKS LONG TERM...ROBERG AVIATION...CLB
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1118 PM CDT SUN APR 13 2014 .UPDATE... ISSUED AT 1106 PM CDT SUN APR 13 2014 PERSISTENT BAND OF SNOW ASSOCIATED WITH WEAK MID LEVEL SHORTWAVE WAS DRIFTING SOUTHEAST THROUGH EASTERN NEBRASKA AND SOUTHWEST IOWA AS OF LATE EVENING. BACK EDGE OF SNOW WAS WORKING THROUGH WESTERN DOUGLAS COUNTY AS OF 11 PM...AND SNOW HAD ENDED AT THE LINCOLN AIRPORT. BANDED STRUCTURE OF RADAR RETURNS SUGGESTS SOME POCKETS OF MODERATE SNOW WILL CONTINUE AS THE WHOLE AREA SHIFTS INTO SOUTHEAST NEBRASKA AND SOUTHWEST IOWA. SPOTTER REPORTS WITHIN THE BANDS INDICATE SNOW AMOUNTS REMAIN UNDER AN INCH...AND MOSTLY ON GRASSY AREAS. BUT WEBCAMS SHOW ACCUMULATION ON ROADS UNDER HEAVIEST BANDS WHICH ARE PRODUCING SLUSHY DRIVING CONDITIONS FOR A TIME BEFORE MELTING OCCURS. CURRENT TRENDS OF THE FORECAST REMAIN ON TRACK WITH AREAS EAST OF A MISSOURI VALLEY TO OMAHA AND LINCOLN LINE EXPERIENCING A FEW HOURS OF LIGHT SNOW WITH AN OCCASIONAL BURST OF MODERATE SNOW. EXPECT ALL THE SNOW TO BE EAST OF SOUTHWEST IOWA BY ABOUT 4 AM. && .SHORT TERM...(TONIGHT THROUGH WEDNESDAY) ISSUED AT 220 PM CDT SUN APR 13 2014 PRIMARY FORECAST CONCERN WILL BE WITH THE FIRST 12 HOURS OF THE FORECAST AND ITS VARIETY OF WEATHER ACROSS THE AREA. COLDER AIR CONTINUES ITS SLOW ADVANCE INTO EASTERN NEBRASKA AT 19Z WITH SNOW NOW FALLING ACROSS NORTHEAST NEBRASKA WEST OF A COLUMBUS TO SIOUX CITY LINE. SHORT RANGE MODELS SUCH AS THE HRRR SUGGEST MAIN ORIENTATION OF THE SNOW BAND WILL GENERALLY SETUP IN AN AREA BOUNDED BY COLUMBUS TO TEKAMAH ON THE SOUTH AND YANKTON TO NELIGH ON THE NORTH THROUGH THE REMAINDER OF THE AFTERNOON AS MID LEVEL CLOSED LOW TRACKS EAST INTO CENTRAL IOWA. SNOW THEN SPREADS EAST AND ENDS FROM THE WEST DURING THE EVENING ACROSS THE REMAINDER OF EASTERN NEBRASKA AND SOUTHWEST IOWA AS THE MID LEVEL LOW CONTINUES TO LIFT TOWARD THE GREAT LAKES REGION AND THE SURFACE LOW MOVES INTO NORTHERN ILLINOIS. EXPECT SNOW TO END SHORTLY AFTER MIDNIGHT IN THE FAR SOUTHEAST CORNER OF THE FORECAST AREA. WILL LIKELY EXPAND WINTER WEATHER ADVISORY ACROSS THIS AREA THROUGH THE 00Z TIME FRAME IN LINE WITH EXPECTED SNOW. CURRENT INDICATIONS ARE FOR 1 TO 3 INCH ACCUMULATIONS BY EVENING IN THE ADVISORY AREA WITH AN INCH OR LESS ELSEWHERE THROUGH THE EVENING. WILL ALSO EXPAND WIND ADVISORY ACROSS REMAINDER OF SOUTHEAST NEBRASKA AND SOUTHWEST IOWA AND EXTEND THROUGH 03Z. WEATHER CONDITIONS IMPROVE FOR THE AREA AFTER TONIGHT ALTHOUGH TEMPERATURES WILL BE ON THE COOL SIDE MONDAY. ANOTHER CLIPPER MOVES INTO THE NORTHERN PLAINS TUESDAY WITH WARMER AIR RETURNING TO THE AREA IN ADVANCE OF THIS SYSTEM. COLD FRONT THEN MOVES SOUTH INTO THE AREA ON WEDNESDAY WITH ANOTHER CHANCE OF RAIN OR SNOW. .LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY) ISSUED AT 220 PM CDT SUN APR 13 2014 COOL AND WET START TO THE EXTENDED PERIOD AS PREVIOUSLY MENTIONED COLD FRONT MOVES SOUTH OF THE AREA WITH ANOTHER COLD UPPER TROUGH DEVELOPING OVER THE CENTRAL PART OF THE COUNTRY. DAY TO DAY WARMING FOLLOWS THIS SYSTEM FOR FRIDAY THROUGH SUNDAY && .AVIATION...(00Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 646 PM CDT SUN APR 13 2014 AREAS OF LIGHT SNOW AND A MIX OF LIGHT RAIN AND SNOW WILL OCCASIONALLY DROP CIGS TO NEAR FL010 AND VSBYS BETWEEN 1SM AND 2SM IN THE KLNK AND KOMA THROUGH THE 04Z TO 06Z TIMEFRAME. THAT PRECIPITATION AND CIGS WILL BE MOVING EAST OF THE AREA NEAR AND AFTER 06Z...WITH IMPROVING CONDITIONS THEREAFTER. EXPECT VFR CONDITIONS AT ALL SITES AFTER 08Z. STRONG NORTH WINDS OF 20 TO 35KT WILL PERSIST THROUGH ABOUT 02Z THEN DECREASE INTO THE 15 TO 25KT RANGE. EXPECT THOSE WINDS TO PERSIST THROUGH MONDAY AFTERNOON BEFORE BEGINNING TO DIMINISH. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ UPDATE...DERGAN SHORT TERM...FOBERT LONG TERM...FOBERT AVIATION...DERGAN
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
702 PM EDT MON APR 14 2014 .SYNOPSIS... VERY MILD WEATHER WILL CONTINUE TONIGHT WITH SCATTERED SHOWERS AND TEMPERATURES ONLY FALLING INTO THE MID TO UPPER 50S. A STRONG COLD FRONT WILL BRING A PERIOD OF HEAVY RAIN TO THE AREA ON TUESDAY... FOLLOWED BY MUCH COLDER AIR AND A BRIEF CHANGE TO SNOW AND SLEET BEFORE THE PRECIPITATION ENDS EARLY TUESDAY EVENING. WEDNESDAY WILL BE UNSEASONABLY COLD... THE MILDER WEATHER WILL RETURN BY LATE THIS WEEK. && .NEAR TERM /UNTIL 2 AM TUESDAY MORNING/... WARM TEMPERATURES OVER THE LAKE PLAIN WERE ENOUGH INSTABILITY TO GET A LINE OF SHOWERS GOING WITH BRIEF HEAVY RAINS AND GUSTY WINDS TO 40 MPH. NO CLOUD TO GROUND LIGHTNING STRIKES WERE PICKED UP BUT SOME IN-CLOUD LIGHTNING WAS REPORTED NORTH OF PENN YAN. TEMPS DROP ABOUT 10 DEGREES AS THE SHOWERS MOVE THROUGH BUT THEN THIS SHOULD LEVEL OUT. THE LINE OF SHOWERS IS CONTINUING TO PROGRESS EAST THROUGH THE CENTRAL PORTION OF OUR FORECAST AREA. BEHIND THIS LINE TO THE WEST A CHANCE OF LIGHT SHOWERS IS POSSIBLE INTO THE OVERNIGHT. TO THE EAST THE LINE IS EXPECTED TO STALL AND WEAKEN AS THE SUNSETS. SCATTERED SHOWERS WILL REMAIN POSSIBLE PAST MIDNIGHT. && .SHORT TERM /2 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/... A STRONG COLD FRONT WILL TRACK ACROSS THE AREA THROUGH THIS PERIOD BRINGING A PERIOD OF HEAVY RAIN TO MUCH OF THE AREA ALONG WITH RAPIDLY FALLING TEMPERATURES AND A LIKELY CHANGE-OVER TO SNOW AND SLEET. DETAILS ARE GIVEN BELOW. A BAND OF SCATTERED SHOWERS MOVING ACROSS THE AREA THIS EVENING IS STILL WELL AHEAD OF THE COLD FRONT WHICH IS BACK TO THE WEST AROUND DTW. THESE SHOWERS WILL TEND TO LIFT NORTHEAST AND WEAKEN THROUGH THIS EVENING BUT THERE STILL APPEARS TO BE A GOOD CHANCE FOR A ROUND OF SHOWERS THIS EVENING AS THIS SYSTEM MOVES ACROSS THE AREA. LATEST RAP MODEL SOUNDINGS HARDLY INDICATING ANY CAPE OVER THE AREA THIS EVENING AND HAVE LEFT OUT ANY THUNDER MENTION. EXPECT A LULL IN THE ACTIVITY OVER NIGHT IN THE WAKE OF THIS SYSTEM... BEFORE RAIN BEGINS TO INCREASE WITH THE APPROACH OF THE COLD FRONT TOWARD DAYBREAK. IT WILL BE A VERY MILD NIGHT WITH SOUTHERLY BREEZES AND LOW TEMPERATURES MOSTLY 55 TO 60... MORE SEASONABLE FOR JUNE THAN MID-APRIL. A STRONG COLD FRONT WILL TRACK SLOWLY EAST ACROSS THE CWA ON TUESDAY. THIS FRONT WILL BE ACCOMPANIED BY STRONG RIGHT-REAR QUAD UPPER DYNAMICS AND A 50 KT LOW-LEVEL SOUTHERLY JET. INSTABILITY ALONG AND AHEAD OF THE FRONT WILL BE MINIMAL BUT CAN`T RULE OUT A FEW RUMBLES OF THUNDER RIGHT WITH THE FRONTAL PASSAGE DURING MIDDAY TUESDAY. AT THIS TIME WE ARE EXPECTING SHOWERS TO INCREASE AHEAD OF THE FRONT EARLY TUESDAY... THEN A BAND OF MODERATE TO HEAVY RAIN WILL LIKELY ACCOMPANY AND FOLLOW THE FRONTAL PASSAGE... LATE TUESDAY MORNING OVER THE FINGER LAKES... AROUND NOON ALONG THE I-81 CORRIDOR... AND EARLY AFTERNOON OVER THE WESTERN CATSKILLS. SOME CONCERN THAT ANY BAND OF HEAVY RAIN THAT DEVELOPS ALONG THE FRONT COULD BE HEAVY ENOUGH TO CAUSE SOME MINOR FLOODING ISSUES IF HEAVY RAIN FALLS DURING A SHORT PERIOD. TOTAL RAINFALL WITH THE SYSTEM IS EXPECTED TO BE IN THE 1 TO 1.5 INCH RANGE. HAVE HELD OFF ON ANY WATCHES AT THIS POINT... BUT A WATCH MAY NEED CONSIDERATION ONCE TIMING AN LOCATION OF ANY HEAVY RAIN BANDS BECOMES MORE CERTAIN. SOUTHWEST WINDS WILL INCREASE TONIGHT AS THE FRONT APPROACHES. SOME GUSTS TO 30 OR 40 MPH WILL BE POSSIBLE OVER HIGHER TERRAIN LATER TONIGHT WITH LIGHTER WINDS AT LOWER ELEVATIONS. NORTHWEST WINDS WILL BE STRONG AND GUSTY BEHIND THE FRONT LATE TUESDAY INTO TUESDAY NIGHT. SOME GUSTS OF 30 TO 40 MPH ARE POSSIBLE. THIS WILL BE AN ANAFRONT WITH SEVERAL HOURS OF PRECIPITATION LINGERING BEHIND THE FRONT. COLD AIR MOVES IN QUICKLY BEHIND THE FRONT WITH RAIN CHANGING TO SLEET OR A MIX OF SLEET AND SNOW OVER THE FINGER LAKES BY LATE MORNING... AND ALONG THE I-81 CORRIDOR BY MID TO LATE AFTERNOON. MODELS ARE IN EXCELLENT AGREEMENT WITH THIS SCENARIO AND INDICATE THE POTENTIAL FOR A WIDESPREAD 1 TO 3 INCHES OF SNOW AND SLEET BY EARLY EVENING TUESDAY FOR MOST OF THE AREA. STEADIER SNOW WILL END ACROSS THE AREA EARLY TUESDAY EVENING BUT 850 MB TEMPERATURES FALL TO AROUND -15 DEGREES C. DESPITE VERY DRY AIR EXPECT THAT THIS SCEANRIO WILL SUPPORT A LITTLE BIT OF LAKE EFFECT SNOW OVER CENTRAL NY TUESDAY EVENING. ANY ADDITIONAL ACCUMULATIONS SHOULD BE LIGHT. && .LONG TERM /WEDNESDAY THROUGH MONDAY/... QUIET WX IN THE MED RNG WITH HIGH PRES BUILDING INTO THE RGN ON WED. AFTER SOME MRNG LAKE CLDS...MOSTLY SUNNY SKIES WILL PREVAIL. FAIR AND DRY WEATHER PERSISTS INTO FRIDAY AS THE SFC HIGH SLIDES OFF THE CST. WE COULD SEE CLDS RETURN IN THE SELY FLOW LATER FRI NGT INTO SAT. THIS WEEKEND`S FCST IS RATHER UNCERTAIN...HINGING ON THE INTERACTION BETWEEN NRN AND SRN STREAM S/WV`S. JUST WENT WITH SLGT CHC/LOW CHC POPS FOR THIS PD. TEMPS WILL BE WELL BLO NORMAL ON WED...A MODERATING TREND AFTERWARDS AND WITH TEMPS RISING TO NEAR OR SLIGHTLY ABV SEASONAL NORMS. && .AVIATION /00Z TUESDAY THROUGH SATURDAY/... VFR ACRS THE AREA THIS AFTN WITH BKN-OVC MID DECK. SCT --SHRA ACRS CNTRL NY LATE THIS AFTN/EARLY EVNG BUT NO RESTRICTIONS XPCTD. LATER TNGT...AREAS OF RAIN AND MVFR CIGS SPREAD INTO THE RGN IN THE 03-06Z TIME FRAME. WDSPRD IFR/MVFR TWDS DAYBREAK AND INTO TUE AFTN. SHARP FNT WILL RESULT IN A TRANSITION TO SLEET LATE IN THE PD AT SYR/ITH/ELM (BASED ON CRNT FNTL TIMING). IN ADDN...WE ARE INDICATING POTNL FOR LLWS WITH FROPA BASED ON IMPRSV SHEAR DISPLAYED IN THE MDL PROFILES. WINDS THIS AFTN SWLY 15-25...AND SRLY TNGT 10-20 WITH HIGHER GUSTS...THEN BECMG NWLY 10-20 BEHIND THE FNT AT WRN SITES. OUTLOOK... TUE NGT...SCT MVFR IN -SHSN CNTRL NY. WED-THU-FRI...VFR. FRI NGT/SAT...MVFR CIGS PSBL IN SELY FLOW OVER NE PA AND SRN NY. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...FLOOD WATCH FROM TUESDAY MORNING THROUGH TUESDAY EVENING FOR NYZ009-037. && $$ SYNOPSIS...MSE NEAR TERM...BMW SHORT TERM...MSE LONG TERM... AVIATION...
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
324 PM EDT MON APR 14 2014 .SYNOPSIS... VERY MILD WEATHER WILL CONTINUE TONIGHT WITH SCATTERED SHOWERS AND TEMPERATURES ONLY FALLING INTO THE MID TO UPPER 50S. A STRONG COLD FRONT WILL BRING A PERIOD OF HEAVY RAIN TO THE AREA ON TUESDAY... FOLLOWED BY MUCH COLDER AIR AND A BRIEF CHANGE TO SNOW AND SLEET BEFORE THE PRECIPITATION ENDS EARLY TUESDAY EVENING. WEDNESDAY WILL BE UNSEASONABLY COLD... THE MILDER WEATHER WILL RETURN BY LATE THIS WEEK. && .NEAR TERM /UNTIL 8 PM THIS EVENING/... CLDS ARE INCRSNG ACRS THE FCST AREA UNDER WARM SWLY FLOW. AREA OF -SHRA ACRS WRN NY AND PA WORKING NEWD BUT LOW LVL AIR MASS IS PRETTY DRY. XPCT SCT --SHRA TO SPREAD INTO THE CNTRL SRN TIER AND WRN FINGER LAKES BY LATE AFTN...SLOWLY SPREADING EWD. CRNT NEAR TERM FCST REFLECTS THIS THINKING. && .SHORT TERM /8 PM THIS EVENING THROUGH TUESDAY NIGHT/... A STRONG COLD FRONT WILL TRACK ACROSS THE AREA THROUGH THIS PERIOD BRINGING A PERIOD OF HEAVY RAIN TO MUCH OF THE AREA ALONG WITH RAPIDLY FALLING TEMPERATURES AND A LIKELY CHANGE-OVER TO SNOW AND SLEET. DETAILS ARE GIVEN BELOW. A BAND OF SCATTERED SHOWERS MOVING ACROSS THE AREA THIS EVENING IS STILL WELL AHEAD OF THE COLD FRONT WHICH IS BACK TO THE WEST AROUND DTW. THESE SHOWERS WILL TEND TO LIFT NORTHEAST AND WEAKEN THROUGH THIS EVENING BUT THERE STILL APPEARS TO BE A GOOD CHANCE FOR A ROUND OF SHOWERS THIS EVENING AS THIS SYSTEM MOVES ACROSS THE AREA. LATEST RAP MODEL SOUNDINGS HARDLY INDICATING ANY CAPE OVER THE AREA THIS EVENING AND HAVE LEFT OUT ANY THUNDER MENTION. EXPECT A LULL IN THE ACTIVITY OVER NIGHT IN THE WAKE OF THIS SYSTEM... BEFORE RAIN BEGINS TO INCREASE WITH THE APPROACH OF THE COLD FRONT TOWARD DAYBREAK. IT WILL BE A VERY MILD NIGHT WITH SOUTHERLY BREEZES AND LOW TEMPERATURES MOSTLY 55 TO 60... MORE SEASONABLE FOR JUNE THAN MID-APRIL. A STRONG COLD FRONT WILL TRACK SLOWLY EAST ACROSS THE CWA ON TUESDAY. THIS FRONT WILL BE ACCOMPANIED BY STRONG RIGHT-REAR QUAD UPPER DYNAMICS AND A 50 KT LOW-LEVEL SOUTHERLY JET. INSTABILITY ALONG AND AHEAD OF THE FRONT WILL BE MINIMAL BUT CAN`T RULE OUT A FEW RUMBLES OF THUNDER RIGHT WITH THE FRONTAL PASSAGE DURING MIDDAY TUESDAY. AT THIS TIME WE ARE EXPECTING SHOWERS TO INCREASE AHEAD OF THE FRONT EARLY TUESDAY... THEN A BAND OF MODERATE TO HEAVY RAIN WILL LIKELY ACCOMPANY AND FOLLOW THE FRONTAL PASSAGE... LATE TUESDAY MORNING OVER THE FINGER LAKES... AROUND NOON ALONG THE I-81 CORRIDOR... AND EARLY AFTERNOON OVER THE WESTERN CATSKILLS. SOME CONCERN THAT ANY BAND OF HEAVY RAIN THAT DEVELOPS ALONG THE FRONT COULD BE HEAVY ENOUGH TO CAUSE SOME MINOR FLOODING ISSUES IF HEAVY RAIN FALLS DURING A SHORT PERIOD. TOTAL RAINFALL WITH THE SYSTEM IS EXPECTED TO BE IN THE 1 TO 1.5 INCH RANGE. HAVE HELD OFF ON ANY WATCHES AT THIS POINT... BUT A WATCH MAY NEED CONSIDERATION ONCE TIMING AN LOCATION OF ANY HEAVY RAIN BANDS BECOMES MORE CERTAIN. SOUTHWEST WINDS WILL INCREASE TONIGHT AS THE FRONT APPROACHES. SOME GUSTS TO 30 OR 40 MPH WILL BE POSSIBLE OVER HIGHER TERRAIN LATER TONIGHT WITH LIGHTER WINDS AT LOWER ELEVATIONS. NORTHWEST WINDS WILL BE STRONG AND GUSTY BEHIND THE FRONT LATE TUESDAY INTO TUESDAY NIGHT. SOME GUSTS OF 30 TO 40 MPH ARE POSSIBLE. THIS WILL BE AN ANAFRONT WITH SEVERAL HOURS OF PRECIPITATION LINGERING BEHIND THE FRONT. COLD AIR MOVES IN QUICKLY BEHIND THE FRONT WITH RAIN CHANGING TO SLEET OR A MIX OF SLEET AND SNOW OVER THE FINGER LAKES BY LATE MORNING... AND ALONG THE I-81 CORRIDOR BY MID TO LATE AFTERNOON. MODELS ARE IN EXCELLENT AGREEMENT WITH THIS SCENARIO AND INDICATE THE POTENTIAL FOR A WIDESPREAD 1 TO 3 INCHES OF SNOW AND SLEET BY EARLY EVENING TUESDAY FOR MOST OF THE AREA. STEADIER SNOW WILL END ACROSS THE AREA EARLY TUESDAY EVENING BUT 850 MB TEMPERATURES FALL TO AROUND -15 DEGREES C. DESPITE VERY DRY AIR EXPECT THAT THIS SCEANRIO WILL SUPPORT A LITTLE BIT OF LAKE EFFECT SNOW OVER CENTRAL NY TUESDAY EVENING. ANY ADDITIONAL ACCUMULATIONS SHOULD BE LIGHT. && .LONG TERM /WEDNESDAY THROUGH MONDAY/... QUIET WX IN THE MED RNG WITH HIGH PRES BUILDING INTO THE RGN ON WED. AFTER SOME MRNG LAKE CLDS...MOSTLY SUNNY SKIES WILL PREVAIL. FAIR AND DRY WEATHER PERSISTS INTO FRIDAY AS THE SFC HIGH SLIDES OFF THE CST. WE COULD SEE CLDS RETURN IN THE SELY FLOW LATER FRI NGT INTO SAT. THIS WEEKEND`S FCST IS RATHER UNCERTAIN...HINGING ON THE INTERACTION BETWEEN NRN AND SRN STREAM S/WV`S. JUST WENT WITH SLGT CHC/LOW CHC POPS FOR THIS PD. TEMPS WILL BE WELL BLO NORMAL ON WED...A MODERATING TREND AFTERWARDS AND WITH TEMPS RISING TO NEAR OR SLIGHTLY ABV SEASONAL NORMS. && .AVIATION /20Z MONDAY THROUGH SATURDAY/... VFR ACRS THE AREA THIS AFTN WITH BKN-OVC MID DECK. SCT --SHRA ACRS CNTRL NY LATE THIS AFTN/EARLY EVNG BUT NO RESTRICTIONS XPCTD. LATER TNGT...AREAS OF RAIN AND MVFR CIGS SPREAD INTO THE RGN IN THE 03-06Z TIME FRAME. WDSPRD IFR/MVFR TWDS DAYBREAK AND INTO TUE AFTN. SHARP FNT WILL RESULT IN A TRANSITION TO SLEET LATE IN THE PD AT SYR/ITH/ELM (BASED ON CRNT FNTL TIMING). IN ADDN...WE ARE INDICATING POTNL FOR LLWS WITH FROPA BASED ON IMPRSV SHEAR DISPLAYED IN THE MDL PROFILES. WINDS THIS AFTN SWLY 15-25...AND SRLY TNGT 10-20 WITH HIGHER GUSTS...THEN BECMG NWLY 10-20 BEHIND THE FNT AT WRN SITES. OUTLOOK... TUE NGT...SCT MVFR IN -SHSN CNTRL NY. WED-THU-FRI...VFR. FRI NGT/SAT...MVFR CIGS PSBL IN SELY FLOW OVER NE PA AND SRN NY. && .FIRE WEATHER... 4 AM MONDAY UPDATE... DEWPOINT TEMPERATURES WILL REMAIN FAIRLY STEADY THROUGH THE DAY BUT TEMPERATURES ARE NOT EXPECTED TO CLIMB AS HIGH AS YESTERDAY, LEADING TO MINIMUM RELATIVE HUMIDITY VALUES REMAINING ABOVE 40% THROUGH THE DAY. SOUTH-SOUTHWEST WINDS WILL BE STRONG AND GUSTY AGAIN TODAY BUT ANY FIRE WEATHER CONCERNS WILL BE PRECLUDED BY INCREASING MOISTURE AHEAD OF AN APPROACHING COLD FRONT. WIDESPREAD RAIN WILL MOVE IN LATE TONIGHT. COLD AIR WILL MOVE IN BEHIND THE FRONT ON TUESDAY AFTERNOON, SWITCHING RAIN OVER TO SNOW SHOWERS BRIEFLY ON TUESDAY NIGHT, MAINLY ACROSS CENTRAL NEW YORK. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...FLOOD WATCH FROM TUESDAY MORNING THROUGH TUESDAY EVENING FOR NYZ009-037. && $$ SYNOPSIS...MSE NEAR TERM...RHB SHORT TERM...MSE LONG TERM...CMG AVIATION... FIRE WEATHER...
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
321 PM EDT MON APR 14 2014 .SYNOPSIS... VERY MILD WEATHER WILL CONTINUE TONIGHT WITH SCATTERED SHOWERS AND TEMPERATURES ONLY FALLING INTO THE MID TO UPPER 50S. A STRONG COLD FRONT WILL BRING A PERIOD OF HEAVY RAIN TO THE AREA ON TUESDAY... FOLLOWED BY MUCH COLDER AIR AND A BRIEF CHANGE TO SNOW AND SLEET BEFORE THE PRECIPITATION ENDS EARLY TUESDAY EVENING. WEDNESDAY WILL BE UNSEASONABLY COLD... THE MILDER WEATHER WILL RETURN BY LATE THIS WEEK. && .NEAR TERM /UNTIL 8 PM THIS EVENING/... CLDS ARE INCRSNG ACRS THE FCST AREA UNDER WARM SWLY FLOW. AREA OF -SHRA ACRS WRN NY AND PA WORKING NEWD BUT LOW LVL AIR MASS IS PRETTY DRY. XPCT SCT --SHRA TO SPREAD INTO THE CNTRL SRN TIER AND WRN FINGER LAKES BY LATE AFTN...SLOWLY SPREADING EWD. CRNT NEAR TERM FCST REFLECTS THIS THINKING. && .SHORT TERM /8 PM THIS EVENING THROUGH TUESDAY NIGHT/... A STRONG COLD FRONT WILL TRACK ACROSS THE AREA THROUGH THIS PERIOD BRINGING A PERIOD OF HEAVY RAIN TO MUCH OF THE AREA ALONG WTIH RAPIDLY FALLING TEMPERATURES AND A LIKELY CHANGE-OVER TO SNOW AND SLEET. DETAILS ARE GIVEN BELOW. BAND OF SCATTERED SHOWERS MOVING ACROSS THE AREA THIS EVNEING ARE STILL WELL AHEAD OF THE COLD FRONT WHICH IS BACK TO THE WEST AROUND DTW. THESE SHOWERS WILL TEND TO LIFT NORTHEAST AND WEAKEN THROUGH THIS EVENING BUT THERE STILL APPEARS TO BE A GOOD CHANCE FOR A ROUND OF SHOWERS THIS EVENING AS THIS SYSTEM MOVES ACROSS THE AREA. LATEST RAP MODEL SOUNDINGS HARDLY INDICATING ANY CAPE OVER THE AREA THIS EVENING AND HAVE LEFT OUT ANY THUNDER MENTION. EXPECT A LULL IN THE ACTIVITY OVER NIGHT IN THE WAKE OF THIS SYSTEM... BEFORE RAIN BEGINS TO INCREASE WITH THE APPROACH OF THE COLD FRONT TOWARD DAYBREAK. IT WILL BE A VERY MILD NIGHT WITH SOUTHERLY BREEZES AND LOW TEMPERATURES MOSTLY 55 TO 60... MORE SEASONABLE FOR JUNE THAN MID-APRIL. A STRONG COLD FRONT WILL TRACK SLOWLY EAST ACROSS THE CWA ON TUESDAY. THIS FRONT WILL BE ACCOMPANIED BY STRONG RIGHT-REAR QUAD UPPER DYNAMICS AND A 50 KT LOW-LEVEL SOUTHERLY JET. INSTABILITY ALONG AND AHEAD OF THE FRONT WILL BE MINIMAL BUT CAN`T RULE OUT A FEW RUMBLES OF THUNDER RIGHT WITH THE FRONTAL PASSAGE DURING MIDDAY TUESDAY. AT THIS TIME WE ARE EXPECTING SHOWERS TO INCREASE AHEAD OF THE FRONT EARLY TUESDAY... THEN A BAND OF MODERATE TO HEAVY RAIN WILL LIKELY ACCOMPANY AND FOLLOW THE FRONTAL PASSAGE... LATE TUESDAY MORNING OVER THE FINGER LAKES... AROUND NOON ALONG THE I-81 CORRIDOR... AND EARLY AFTERNOON OVER THE WESTERN CATSKILLS. SOME CONCERN THAT ANY BAND OF HEAVY RAIN THAT DEVELOPS ALONG THE FRONT COULD BE HEAVY ENOUGH TO CAUSE SOME MINOR FLOODING ISSUES IF HEAVY RAIN FALLS DURING A SHORT PERIOD. TOTAL RAINFALL WITH THE SYSTEM IS EXPECTED TO BE IN THE 1 TO 1.5 INCH RANGE. HAVE HELD OFF ON ANY WATCHES AT THIS POINT... BUT A WATCH MAY NEED CONSIDERATION ONCE TIMING AN LOCATION OF ANY HEAVY RAIN BANDS BECOMES MORE CERTAIN. SOUTHWEST WINDS WILL INCREASE TONIGHT AS THE FRONT APPROACHES. SOME GUSTS TO 30 OR 40 MPH WILL BE POSSIBLE OVER HIGHER TERRAIN LATER TONIGHT WITH LIGHTER WINDS AT LOWER ELEVATIONS. NORTHWEST WINDS WILL BE STRONG AND GUSTY BEHIND THE FRONT LATE TUESDAY INTO TUESDAY NIGHT. SOME GUSTS OF 30 TO 40 MPH ARE POSSIBLE. THIS WILL BE AN ANAFRONT WITH SEVERAL HOURS OF PRECIPITATION LINGERING BEHIND THE FRONT. COLD AIR MOVES IN QUICKLY BEHIND THE FRONT WITH RAIN CHANGING TO SLEET OR A MIX OF SLEET AND SNOW OVER THE FINGER LAKES BY LATE MORNING... AND ALONG THE I-81 CORRIDOR BY MID TO LATE AFTERNOON. MODELS ARE IN EXCELLENT AGREEMENT WITH THIS SCENARIO AND INDICATE THE POTENTIAL FOR A WIDESPREAD 1 TO 3 INCHES OF SNOW AND SLEET BY EARLY EVENING TUESDAY FOR MOST OF THE AREA. STEADIER SNOW WILL END ACROSS THE AREA EARLY TUESDAY EVENING BUT 850 MB TEMPERATURES FALL TO AROUND -15 DEGREES C. DESPITE VERY DRY AIR EXPECT THAT THIS SCEANRIO WILL SUPPORT A LITTLE BIT OF LAKE EFFECT SNOW OVER CENTRAL NY TUESDAY EVENING. ANY ADDITIONAL ACCUMULATIONS SHOULD BE LIGHT. && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... QUIET WX IN THE MED RNG WITH HIGH PRES BUILDING INTO THE RGN ON WED. AFTER SOME MRNG LAKE CLDS...MOSTLY SUNNY SKIES WILL PREVAIL. FAIR AND DRY WEATHER PERSISTS INTO FRIDAY AS THE SFC HIGH SLIDES OFF THE CST. WE COULD SEE CLDS RETURN IN THE SELY FLOW LATER FRI NGT INTO SAT. THIS WEEKEND`S FCST IS RATHER UNCERTAIN...HINGING ON THE INTERACTION BETWEEN NRN AND SRN STREAM S/WV`S. JUST WENT WITH SLGT CHC/LOW CHC POPS FOR THIS PD. TEMPS WILL BE WELL BLO NORMAL ON WED...A MODERATING TREND AFTERWARDS AND WITH TEMPS RISING TO NEAR OR SLIGHTLY ABV SEASONAL NORMS. && .AVIATION /19Z MONDAY THROUGH SATURDAY/... VFR ACRS THE AREA THIS AFTN WITH BKN-OVC MID DECK. SCT --SHRA ACRS CNTRL NY LATE THIS AFTN/EARLY EVNG BUT NO RESTRICTIONS XPCTD. LATER TNGT...AREAS OF RAIN AND MVFR CIGS SPREAD INTO THE RGN IN THE 03-06Z TIME FRAME. WDSPRD IFR/MVFR TWDS DAYBREAK AND INTO TUE AFTN. SHARP FNT WILL RESULT IN A TRANSITION TO SLEET LATE IN THE PD AT SYR/ITH/ELM (BASED ON CRNT FNTL TIMING). IN ADDN...WE ARE INDICATING POTNL FOR LLWS WITH FROPA BASED ON IMPRSV SHEAR DISPLAYED IN THE MDL PROFILES. WINDS THIS AFTN SWLY 15-25...AND SRLY TNGT 10-20 WITH HIGHER GUSTS...THEN BECMG NWLY 10-20 BEHIND THE FNT AT WRN SITES. OUTLOOK... TUE NGT...SCT MVFR IN -SHSN CNTRL NY. WED-THU-FRI...VFR. FRI NGT/SAT...MVFR CIGS PSBL IN SELY FLOW OVER NE PA AND SRN NY. && .FIRE WEATHER... 4 AM MONDAY UPDATE... DEWPOINT TEMPERATURES WILL REMAIN FAIRLY STEADY THROUGH THE DAY BUT TEMPERATURES ARE NOT EXPECTED TO CLIMB AS HIGH AS YESTERDAY, LEADING TO MINIMUM RELATIVE HUMIDITY VALUES REMAINING ABOVE 40% THROUGH THE DAY. SOUTH-SOUTHWEST WINDS WILL BE STRONG AND GUSTY AGAIN TODAY BUT ANY FIRE WEATHER CONCERNS WILL BE PRECLUDED BY INCREASING MOISTURE AHEAD OF AN APPROACHING COLD FRONT. WIDESPREAD RAIN WILL MOVE IN LATE TONIGHT. COLD AIR WILL MOVE IN BEHIND THE FRONT ON TUESDAY AFTERNOON, SWITCHING RAIN OVER TO SNOW SHOWERS BRIEFLY ON TUESDAY NIGHT, MAINLY ACROSS CENTRAL NEW YORK. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...FLOOD WATCH FROM TUESDAY MORNING THROUGH TUESDAY EVENING FOR NYZ009-037. && $$ SYNOPSIS...MSE NEAR TERM...RHB SHORT TERM...MSE LONG TERM...CMG AVIATION... FIRE WEATHER...
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
835 AM EDT MON APR 14 2014 .SYNOPSIS... THE WEATHER WILL BE MILD AND DRY THROUGH MOST OF TODAY. MEANWHILE LOW PRESSURE OVER THE CENTRAL U.S. WILL MOVE NORTHEAST AND BRING SHOWERS TO THE AREA LATE THIS AFTERNOON INTO TONIGHT. ON TUESDAY, A STRONG COLD FRONT WILL PASS THROUGH. LOCALLY HEAVY RAIN WILL BE POSSIBLE AHEAD OF THE COLD FRONT WITH THE POTENTIAL FOR ACCUMULATING SNOWS BEHIND IT ACROSS CENTRAL NEW YORK. HIGH PRESSURE WILL BRING A RETURN TO FAIR WEATHER ON WEDNESDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 830 AM UPDATE... FCST IN GOOD SHAPE. A FEW MDLS DVLP SCT CONVECTION THIS AFTN ALONG A WEAK PRE-FNTL SFC TROF BUT INSPECTION OF PROFILES SUGGESTS --SHRA OUT OF A MID DECK WITH ONLY A FEW HUNDRED JOULES OF MID LVL INSTABILITY. TEMPS WILL BE TRICKY THIS AFTN. 925 TEMPS WILL BE A FEW DEG COOLER AND WE`LL HAVE MORE IN THE WAY OF CLD CVR BUT WE`RE STARTING OUT VERY MILD...SO NO CHGS THERE. PREV BLO... 630 AM UPDATE... 993MB SFC LOW HAS NOW MVD INTO NRN LOWER MICHIGAN WITH STRONG COLD FRONT DRAPED BACK THRU THE MIDWEST. AS IT CROSSED CHICAGO, O-HARE DROPPED 16 DEGREES IN ONE HOUR. THIS SYSTEM WILL EVENTUALLY CROSS OUR AREA TOMORROW. IN THE MEANTIME HAVE HAD TO DO SOME FINAGLING WITH TEMPS FOR TDA AS MOST OF CWA WERE WITHIN 4-5 DEGREES OF HIGH TEMPS TDA. WENT SIGNIFICANTLY ABV GUIDANCE FOR THIS UPDATE AS MOST LOCALES SHUD EASILY PUSH INTO THE U70S. LATEST HRRR NOW HAS WIDESPREAD RAIN INTO WRN ZONES BY 22Z AND THIS WL NEED TO BE MONITORED THROUGHOUT THE DAY. PREV DISCO BLO... 155 AM UPDATE... SPRINGTIME STORM SYSTEM THAT BROUGHT SVR WX TO THE PLAINS YDA WL BE HEADED NORTHEAST OVR THE NEXT SEVERAL DAYS. WM FNT DRAPED ACRS SRN ONTARIO AND NRN NY STATE EXTENDS FM SFC LOW LOCATED OVR THE QUAD CITIES REGION. ASSOC H5 TROF IS SPINNING THRU THE CNTRL PLAINS WITH WIDESPREAD AREA OF SHOWERS/TSTMS ALONG MS RVR. ALL THIS MEANS WITH REGARD TO OUR WX IS A MILD SRLY FLOW CONTG TDA. GOM IS CURRENTLY WIDE OPEN AND DRAWING IN WARM/MOIST AIR TO CNTRL PART OF NATION WITH PW VALUES WELL ABV 1 INCH. AS TROF SLIDES EVER CLOSER TO CWA THRU THE AFTN EXPECT MOISTURE TO INCRS TO OVR 1.00 INCHES. THIS HELPS TO INCRS DWPT VALUES INTO THE 50S AND PRECLUDE FIRE WX CONCERNS FOR TDA AS OPPOSED TO YDA. IN ADDITION AN INCRS IN CLDS FM THE APPCHG SYSTEM WL SPREAD MOCLDY SKIES TO WRN ZONES DRG THE AFTN HRS WITH A HIGH THIN CIRRUS EXPECTED RMNDR OF AREA. THIS WL HELP TO TEMPER TEMP RISE TDA WITH MOST HIGHS IN THE M70S. WARM ADVECTION WL COMBINE WITH APPCHG UL FRCG AND LGT SHOWERS WL START TO DVLP ACRS THE WEST BTWN 18Z AND 21Z THIS AFTN BFR SLIDING EAST, PERHAPS GETTING AS FAR EAST AS THE I-81 CORRIDOR IN CNY BY 00Z TONIGHT. MODELS AGREE WITH PLACEMENT OF CDFNT AT 00Z TONIGHT BUT DIFFER WITH REGARD TO QPF WITH GFS MUCH MORE BULLISH THAN EURO AND NAM. WUD CERTAINLY NOT BE SURPRISED TO SEE A SPRINKLE IN CNTRL SXNS OF CWA UNDER STRONG WARM ADVECTION BUT FEEL THE CRUX OF THE PCPN WL BE FELT IN THE FINGER LKS REGION THIS AFTN. && .SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/... 4 AM UPDATE... POPS INCRS TONIGHT FM WEST TO EAST AS FRCG FM FRONT MVS CLOSER TO CWA. LKLY POPS EXPECTED BY 06Z, THEN INCRSG TO 100 POPS BY MRNG. GIVEN STRONG MOISTURE SURGE (THETA-E RIDGE) AND WARM AIR ADVECTION HV GONE WITH MORE SHOWERY MENTION THRU 09Z TONIGHT. H5 LOW WL BE SITTING UP ACRS HUDSON BAY WITH L/WV TROF BCMG NEGATIVELY TILTED TUE MRNG. 250MB SPEED MAX WL STRENGTHEN TO +120KTS BY DAYBREAK WITH CWA IN RIGHT-ENTRANCE REGION ARND 09Z, THUS WL GO WITH MORE OF A RAIN SCENARIO AFT THIS TIME. HV ADDED IN CHC FOR THUNDER DRG THE OVRNGT AS SI`S APPRCH ZERO, MLCAPES ARND 100 J/KG AND K-INDICES > 30. 00Z MODELS AGREE THAT CDFNT WL BE ENTERING INTO WRN ZONES BY 12Z TUESDAY. TEMPS WL FALL THRU THE DAY TUE IN CNY AS CDFNT COMES BLASTING THRU. MAY SEE A BRIEF RISE IN TEMPS ACRS SERN ZONES DRG THE MRNG BFR HOLDING STEADY THEN FALLING STEADILY AFT 18Z. HV SIDED MORE WITH THE TIMING OF THE CHANGEOVER FM RAIN TO SNOW/SLEET WITH THE GFS AND EURO AS NAM SEEMS TO BE TOO SLOW. EXPECT ALL RAIN DRG THE MRNG HRS AND THEN SLOWLY MIXING WITH SLEET BY EARLY AFTN ACRS THE FINGER LKS, THEN BCMG ALL SNOW AFT 21Z IN THE FINGER LKS. PCPN WL START TO MIX WITH SLEET AND SNOW AFT 21Z ACRS THE I-81 CORRIDOR IN NY STATE WITH RAIN EXPECTED THRU 00Z WED IN PIKE AND SULLIVAN CNTYS. EXPECT ALL SNOW SHOWERS TUE NGT WITH POSSIBLE EXCEPTION OF FAR SERN ZONES EARLY AS THEY TRANSITION OVR. SNOWFALL AMNTS FM TIME OF TRANSITION (LATE AFTN TUE) UNTIL PCPN EXITS STAGE RIGHT ARND 06Z WED LOOKS TO BE ON THE ORDER OF 1-1.5 INCHES. WITH H8 TEMPS PROGGED TO DROP TO NR -14C WED MRNG, EXPECT OVRNGT LOWS TO DIP INTO THE TEENS. THIS IS UNDER STRONG NW WINDS AS WELL. IF WINDS CAN DECOUPLE, TEMPS MAY DROP EVEN LOWER. THIS WUD PUT RECORD LOWS IN JEOPARDY FOR THIS DATE. KBGM`S RECORD LOW IS 24F, KAVP IS 20F AND KSYR IS 23F. UNDER FULL SUN WITH HIPRES BUILDING IN ON WED, MAX TEMPS WL QUICKLY CLIMB INTO THE 40S. HIGH WL SHIFT OFF TO THE EAST WED NGT, ALLOWING RETURN FLOW TO RE-ESTABLISH ITSELF. && .LONG TERM /THURSDAY THROUGH SUNDAY/... 315 AM UPDATE... NO MAJOR CHANGES MADE THIS MORNING AS A FAIR AMOUNT OF MODEL DISAGREEMENT STILL EXISTS WITH NEXT WEEKEND/S STORM SYSTEM. BEFORE THIS HOWEVER...DRY BUT COOLER WEATHER WILL PREVAIL THROUGH THE REMAINDER OF THE WORK WEEK AS STRONG HIGH PRESSURE REMAINS ENTRENCHED OVER THE NORTHEAST AND EASTERN CANADA. IN TERMS OF NEXT WEEKEND/S STORM SYSTEM...THE GFS TAKES A SFC LOW DIRECTLY OVER OUR FCST REGION...WHILE THE ECMWF SHOWS A SFC LOW APPROACHING FROM THE SOUTHWEST WITH THIS FEATURE GRADUALLY LOOSING STEAM AS ENERGY TRANSFERS TO A DEVELOPING COASTAL LOW OFF THE EASTERN SEABOARD. UNDER THE LATTER SCENARIO...MUCH OF OUR FCST REGION IS SPARED OF APPRECIABLE RAINFALL. FOR WHAT ITS WORTH...THE CANADIAN-CMC TOO SHOWS TRANSFERRING ENERGY ALBEIT A LITTLE FURTHER NORTH THAN THE ECMWF. IF THIS WERE TO PANE OUT AS ADVERTISED...SOME SOME PRECIP WOULD LIKELY WORK NORTH INTO OUR AREA. AS RESULT OF THIS THIRD SOLUTION...WILL MAINTAIN CHC POPS ACROSS THE SOUTHERN 2/3RDS OF THE FCST REGION FRIDAY NIGHT AND SATURDAY. PREVIOUS LONG TERM DISCUSSION... MEDIUM RANGE MODELS START OUT IN GOOD AGREEMENT EARLY IN THE EXTENDED PERIOD THEN DIVERGE BY NEXT WEEKEND. INITIALLY SFC HIGH PRES OVER NRN NEW ENGLAND AND NOVA SCOTIA WILL BRING FAIR AND COOL WEATHER TO THE AREA WITH LOWS WED NIGHT IN THE MID TO UPPER 20S FOLLOWED BY UPPER 20S TO MID 30S ON THURSDAY NIGHT. MAXES BOTH THURSDAY AND FRIDAY WILL RANGE IN THE 50S WITH SOME MODIFICATION ON FRIDAY. FRIDAY NIGHT THROUGH SUNDAY THE OPERATIONAL GFS TAKES A SFC LOW IN THE TN VALLEY AND TRACKS IT NORTHEAST ACROSS OUR VCNTY THEN INTO EASTERN CANADA BY SUNDAY. A WET SCENARIO FOLLOWED BY WRAP AROUND MOISTURE SATURDAY NIGHT INTO SUNDAY. THE ECMWF PLACES THIS FEATURE FARTHER SOUTH AND WEAKER THEN MOVES IT OFF THE MID ATLANTIC COAST KEEPING THE REGION BASICALLY DRY. FOLLOWED HPC GUIDANCE WHICH KEEPS THE SYSTEM TO OUR SOUTH BUT WILL INCLUDE CHC POPS FROM FRIDAY NIGHT THROUGH SATURDAY NIGHT FOR RAIN SHOWERS. && .AVIATION /13Z MONDAY THROUGH FRIDAY/... VFR CONDITIONS OUT OF THE GATE THIS MORNING. MAIN STORY THROUGH THE DAY WILL BE STRONG SOUTHWEST WINDS WITH GUSTS IN EXCESS OF 25 KTS POSSIBLE AT ALL SITES. FCST MODELS SHOW SOME SHWR ACTIVITY DEVELOPING BY MID/LATE AFTERNOON...HOWEVER OVERALL CONFIDENCE IS TO LOW AT THIS POINT TO INCLUDE IN THE FCST. MUCH BETTER CHANCES FOR PRECIP WILL ARRIVE SHORTLY AFTER 00Z AS PRECIP SHIELD ASSOCIATED WITH COLD FRONT APPROACHES. AS THIS OCCURS...EXPECT CATEGORICAL DECREASES TO MVFR AND POTENTIALLY IFR CONDITIONS AS STEADY PRECIP MOVES IN. MOST LIKELY CANDIDATES FOR IFR DURING THE OVERNIGHT PERIOD WILL BE ITH AND BGM...WITH MVFR EXPECTED ELSEWHERE. OUTLOOK... TUE...RESTRICTIONS IN SCATTERED RAIN SHOWERS AND ISOLATED THUNDER TUESDAY MORNING...WITH RAIN CHANGING TO SNOW TUE AFTERNOON/EVENING. TUE NGT...RESTRICTIONS POSSIBLE IN SCATTERED SNOW SHOWERS. WED-THU-FRI...VFR. && .FIRE WEATHER... 4 AM MONDAY UPDATE... DEWPOINT TEMPERATURES WILL REMAIN FAIRLY STEADY THROUGH THE DAY BUT TEMPERATURES ARE NOT EXPECTED TO CLIMB AS HIGH AS YESTERDAY, LEADING TO MINIMUM RELATIVE HUMIDITY VALUES REMAINING ABOVE 40% THROUGH THE DAY. SOUTH-SOUTHWEST WINDS WILL BE STRONG AND GUSTY AGAIN TODAY BUT ANY FIRE WEATHER CONCERNS WILL BE PRECLUDED BY INCREASING MOISTURE AHEAD OF AN APPROACHING COLD FRONT. WIDESPREAD RAIN WILL MOVE IN LATE TONIGHT. COLD AIR WILL MOVE IN BEHIND THE FRONT ON TUESDAY AFTERNOON, SWITCHING RAIN OVER TO SNOW SHOWERS BRIEFLY ON TUESDAY NIGHT, MAINLY ACROSS CENTRAL NEW YORK. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...NONE. && $$ SYNOPSIS...PVN NEAR TERM...PVN SHORT TERM...PVN LONG TERM...CMG/RRM AVIATION...CMG FIRE WEATHER...
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
652 AM EDT MON APR 14 2014 .SYNOPSIS... THE WEATHER WILL BE MILD AND DRY THROUGH MOST OF TODAY. MEANWHILE LOW PRESSURE OVER THE CENTRAL U.S. WILL MOVE NORTHEAST AND BRING SHOWERS TO THE AREA LATE THIS AFTERNOON INTO TONIGHT. ON TUESDAY, A STRONG COLD FRONT WILL PASS THROUGH. LOCALLY HEAVY RAIN WILL BE POSSIBLE AHEAD OF THE COLD FRONT WITH THE POTENTIAL FOR ACCUMULATING SNOWS BEHIND IT ACROSS CENTRAL NEW YORK. HIGH PRESSURE WILL BRING A RETURN TO FAIR WEATHER ON WEDNESDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 630 AM UPDATE... 993MB SFC LOW HAS NOW MVD INTO NRN LOWER MICHIGAN WITH STRONG COLD FRONT DRAPED BACK THRU THE MIDWEST. AS IT CROSSED CHICAGO, O-HARE DROPPED 16 DEGREES IN ONE HOUR. THIS SYSTEM WILL EVENTUALLY CROSS OUR AREA TOMORROW. IN THE MEANTIME HAVE HAD TO DO SOME FINAGLING WITH TEMPS FOR TDA AS MOST OF CWA WERE WITHIN 4-5 DEGREES OF HIGH TEMPS TDA. WENT SIGNIFICANTLY ABV GUIDANCE FOR THIS UPDATE AS MOST LOCALES SHUD EASILY PUSH INTO THE U70S. LATEST HRRR NOW HAS WIDESPREAD RAIN INTO WRN ZONES BY 22Z AND THIS WL NEED TO BE MONITORED THROUGHOUT THE DAY. PREV DISCO BLO... 155 AM UPDATE... SPRINGTIME STORM SYSTEM THAT BROUGHT SVR WX TO THE PLAINS YDA WL BE HEADED NORTHEAST OVR THE NEXT SEVERAL DAYS. WM FNT DRAPED ACRS SRN ONTARIO AND NRN NY STATE EXTENDS FM SFC LOW LOCATED OVR THE QUAD CITIES REGION. ASSOC H5 TROF IS SPINNING THRU THE CNTRL PLAINS WITH WIDESPREAD AREA OF SHOWERS/TSTMS ALONG MS RVR. ALL THIS MEANS WITH REGARD TO OUR WX IS A MILD SRLY FLOW CONTG TDA. GOM IS CURRENTLY WIDE OPEN AND DRAWING IN WARM/MOIST AIR TO CNTRL PART OF NATION WITH PW VALUES WELL ABV 1 INCH. AS TROF SLIDES EVER CLOSER TO CWA THRU THE AFTN EXPECT MOISTURE TO INCRS TO OVR 1.00 INCHES. THIS HELPS TO INCRS DWPT VALUES INTO THE 50S AND PRECLUDE FIRE WX CONCERNS FOR TDA AS OPPOSED TO YDA. IN ADDITION AN INCRS IN CLDS FM THE APPCHG SYSTEM WL SPREAD MOCLDY SKIES TO WRN ZONES DRG THE AFTN HRS WITH A HIGH THIN CIRRUS EXPECTED RMNDR OF AREA. THIS WL HELP TO TEMPER TEMP RISE TDA WITH MOST HIGHS IN THE M70S. WARM ADVECTION WL COMBINE WITH APPCHG UL FRCG AND LGT SHOWERS WL START TO DVLP ACRS THE WEST BTWN 18Z AND 21Z THIS AFTN BFR SLIDING EAST, PERHAPS GETTING AS FAR EAST AS THE I-81 CORRIDOR IN CNY BY 00Z TONIGHT. MODELS AGREE WITH PLACEMENT OF CDFNT AT 00Z TONIGHT BUT DIFFER WITH REGARD TO QPF WITH GFS MUCH MORE BULLISH THAN EURO AND NAM. WUD CERTAINLY NOT BE SURPRISED TO SEE A SPRINKLE IN CNTRL SXNS OF CWA UNDER STRONG WARM ADVECTION BUT FEEL THE CRUX OF THE PCPN WL BE FELT IN THE FINGER LKS REGION THIS AFTN. && .SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/... 4 AM UPDATE... POPS INCRS TONIGHT FM WEST TO EAST AS FRCG FM FRONT MVS CLOSER TO CWA. LKLY POPS EXPECTED BY 06Z, THEN INCRSG TO 100 POPS BY MRNG. GIVEN STRONG MOISTURE SURGE (THETA-E RIDGE) AND WARM AIR ADVECTION HV GONE WITH MORE SHOWERY MENTION THRU 09Z TONIGHT. H5 LOW WL BE SITTING UP ACRS HUDSON BAY WITH L/WV TROF BCMG NEGATIVELY TILTED TUE MRNG. 250MB SPEED MAX WL STRENGTHEN TO +120KTS BY DAYBREAK WITH CWA IN RIGHT-ENTRANCE REGION ARND 09Z, THUS WL GO WITH MORE OF A RAIN SCENARIO AFT THIS TIME. HV ADDED IN CHC FOR THUNDER DRG THE OVRNGT AS SI`S APPRCH ZERO, MLCAPES ARND 100 J/KG AND K-INDICES > 30. 00Z MODELS AGREE THAT CDFNT WL BE ENTERING INTO WRN ZONES BY 12Z TUESDAY. TEMPS WL FALL THRU THE DAY TUE IN CNY AS CDFNT COMES BLASTING THRU. MAY SEE A BRIEF RISE IN TEMPS ACRS SERN ZONES DRG THE MRNG BFR HOLDING STEADY THEN FALLING STEADILY AFT 18Z. HV SIDED MORE WITH THE TIMING OF THE CHANGEOVER FM RAIN TO SNOW/SLEET WITH THE GFS AND EURO AS NAM SEEMS TO BE TOO SLOW. EXPECT ALL RAIN DRG THE MRNG HRS AND THEN SLOWLY MIXING WITH SLEET BY EARLY AFTN ACRS THE FINGER LKS, THEN BCMG ALL SNOW AFT 21Z IN THE FINGER LKS. PCPN WL START TO MIX WITH SLEET AND SNOW AFT 21Z ACRS THE I-81 CORRIDOR IN NY STATE WITH RAIN EXPECTED THRU 00Z WED IN PIKE AND SULLIVAN CNTYS. EXPECT ALL SNOW SHOWERS TUE NGT WITH POSSIBLE EXCEPTION OF FAR SERN ZONES EARLY AS THEY TRANSITION OVR. SNOWFALL AMNTS FM TIME OF TRANSITION (LATE AFTN TUE) UNTIL PCPN EXITS STAGE RIGHT ARND 06Z WED LOOKS TO BE ON THE ORDER OF 1-1.5 INCHES. WITH H8 TEMPS PROGGED TO DROP TO NR -14C WED MRNG, EXPECT OVRNGT LOWS TO DIP INTO THE TEENS. THIS IS UNDER STRONG NW WINDS AS WELL. IF WINDS CAN DECOUPLE, TEMPS MAY DROP EVEN LOWER. THIS WUD PUT RECORD LOWS IN JEOPARDY FOR THIS DATE. KBGM`S RECORD LOW IS 24F, KAVP IS 20F AND KSYR IS 23F. UNDER FULL SUN WITH HIPRES BUILDING IN ON WED, MAX TEMPS WL QUICKLY CLIMB INTO THE 40S. HIGH WL SHIFT OFF TO THE EAST WED NGT, ALLOWING RETURN FLOW TO RE-ESTABLISH ITSELF. && .LONG TERM /THURSDAY THROUGH SUNDAY/... 315 AM UPDATE... NO MAJOR CHANGES MADE THIS MORNING AS A FAIR AMOUNT OF MODEL DISAGREEMENT STILL EXISTS WITH NEXT WEEKEND/S STORM SYSTEM. BEFORE THIS HOWEVER...DRY BUT COOLER WEATHER WILL PREVAIL THROUGH THE REMAINDER OF THE WORK WEEK AS STRONG HIGH PRESSURE REMAINS ENTRENCHED OVER THE NORTHEAST AND EASTERN CANADA. IN TERMS OF NEXT WEEKEND/S STORM SYSTEM...THE GFS TAKES A SFC LOW DIRECTLY OVER OUR FCST REGION...WHILE THE ECMWF SHOWS A SFC LOW APPROACHING FROM THE SOUTHWEST WITH THIS FEATURE GRADUALLY LOOSING STEAM AS ENERGY TRANSFERS TO A DEVELOPING COASTAL LOW OFF THE EASTERN SEABOARD. UNDER THE LATTER SCENARIO...MUCH OF OUR FCST REGION IS SPARED OF APPRECIABLE RAINFALL. FOR WHAT ITS WORTH...THE CANADIAN-CMC TOO SHOWS TRANSFERRING ENERGY ALBEIT A LITTLE FURTHER NORTH THAN THE ECMWF. IF THIS WERE TO PANE OUT AS ADVERTISED...SOME SOME PRECIP WOULD LIKELY WORK NORTH INTO OUR AREA. AS RESULT OF THIS THIRD SOLUTION...WILL MAINTAIN CHC POPS ACROSS THE SOUTHERN 2/3RDS OF THE FCST REGION FRIDAY NIGHT AND SATURDAY. PREVIOUS LONG TERM DISCUSSION... MEDIUM RANGE MODELS START OUT IN GOOD AGREEMENT EARLY IN THE EXTENDED PERIOD THEN DIVERGE BY NEXT WEEKEND. INITIALLY SFC HIGH PRES OVER NRN NEW ENGLAND AND NOVA SCOTIA WILL BRING FAIR AND COOL WEATHER TO THE AREA WITH LOWS WED NIGHT IN THE MID TO UPPER 20S FOLLOWED BY UPPER 20S TO MID 30S ON THURSDAY NIGHT. MAXES BOTH THURSDAY AND FRIDAY WILL RANGE IN THE 50S WITH SOME MODIFICATION ON FRIDAY. FRIDAY NIGHT THROUGH SUNDAY THE OPERATIONAL GFS TAKES A SFC LOW IN THE TN VALLEY AND TRACKS IT NORTHEAST ACROSS OUR VCNTY THEN INTO EASTERN CANADA BY SUNDAY. A WET SCENARIO FOLLOWED BY WRAP AROUND MOISTURE SATURDAY NIGHT INTO SUNDAY. THE ECMWF PLACES THIS FEATURE FARTHER SOUTH AND WEAKER THEN MOVES IT OFF THE MID ATLANTIC COAST KEEPING THE REGION BASICALLY DRY. FOLLOWED HPC GUIDANCE WHICH KEEPS THE SYSTEM TO OUR SOUTH BUT WILL INCLUDE CHC POPS FROM FRIDAY NIGHT THROUGH SATURDAY NIGHT FOR RAIN SHOWERS. && .AVIATION /12Z MONDAY THROUGH FRIDAY/... VFR CONDITIONS OUT OF THE GATE THIS MORNING. MAIN STORY THROUGH THE DAY WILL BE STRONG SOUTHWEST WINDS WITH GUSTS IN EXCESS OF 25 KTS POSSIBLE AT ALL SITES. FCST MODELS SHOW SOME SHWR ACTIVITY DEVELOPING BY MID/LATE AFTERNOON...HOWEVER OVERALL CONFIDENCE IS TO LOW AT THIS POINT TO INCLUDE IN THE FCST. MUCH BETTER CHANCES FOR PRECIP WILL ARRIVE SHORTLY AFTER 00Z AS PRECIP SHIELD ASSOCIATED WITH COLD FRONT APPROACHES. AS THIS OCCURS...EXPECT CATEGORICAL DECREASES TO MVFR AND POTENTIALLY IFR CONDITIONS AS STEADY PRECIP MOVES IN. MOST LIKELY CANDIDATES FOR IFR DURING THE OVERNIGHT PERIOD WILL BE ITH AND BGM...WITH MVFR EXPECTED ELSEWHERE. OUTLOOK... TUE...RESTRICTIONS IN SCATTERED RAIN SHOWERS AND ISOLATED THUNDER TUESDAY MORNING...WITH RAIN CHANGING TO SNOW TUE AFTERNOON/EVENING. TUE NGT...RESTRICTIONS POSSIBLE IN SCATTERED SNOW SHOWERS. WED-THU-FRI...VFR. && .FIRE WEATHER... 4 AM MONDAY UPDATE... DEWPOINT TEMPERATURES WILL REMAIN FAIRLY STEADY THROUGH THE DAY BUT TEMPERATURES ARE NOT EXPECTED TO CLIMB AS HIGH AS YESTERDAY, LEADING TO MINIMUM RELATIVE HUMIDITY VALUES REMAINING ABOVE 40% THROUGH THE DAY. SOUTH-SOUTHWEST WINDS WILL BE STRONG AND GUSTY AGAIN TODAY BUT ANY FIRE WEATHER CONCERNS WILL BE PRECLUDED BY INCREASING MOISTURE AHEAD OF AN APPROACHING COLD FRONT. WIDESPREAD RAIN WILL MOVE IN LATE TONIGHT. COLD AIR WILL MOVE IN BEHIND THE FRONT ON TUESDAY AFTERNOON, SWITCHING RAIN OVER TO SNOW SHOWERS BRIEFLY ON TUESDAY NIGHT, MAINLY ACROSS CENTRAL NEW YORK. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...NONE. && $$ SYNOPSIS...PVN NEAR TERM...PVN SHORT TERM...PVN LONG TERM...CMG/RRM AVIATION...CMG FIRE WEATHER...
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
628 AM EDT MON APR 14 2014 .SYNOPSIS... THE WEATHER WILL BE MILD AND DRY THROUGH MOST OF TODAY. MEANWHILE LOW PRESSURE OVER THE CENTRAL U.S. WILL MOVE NORTHEAST AND BRING SHOWERS TO THE AREA LATE THIS AFTERNOON INTO TONIGHT. ON TUESDAY, A STRONG COLD FRONT WILL PASS THROUGH. LOCALLY HEAVY RAIN WILL BE POSSIBLE AHEAD OF THE COLD FRONT WITH THE POTENTIAL FOR ACCUMULATING SNOWS BEHIND IT ACROSS CENTRAL NEW YORK. HIGH PRESSURE WILL BRING A RETURN TO FAIR WEATHER ON WEDNESDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 630 AM UPDATE... 993MB SFC LOW HAS NOW MVD INTO NRN LOWER MICHIGAN WITH STRONG COLD FRONT DRAPED BACK THRU THE MIDWEST. AS IT CROSSED CHICAGO, O-HARE DROPPED 16 DEGREES IN ONE HOUR. THIS SYSTEM WILL EVENTUALLY CROSS OUR AREA TOMORROW. IN THE MEANTIME HAVE HAD TO DO SOME FINAGLING WITH TEMPS FOR TDA AS MOST OF CWA WERE WITHIN 4-5 DEGREES OF HIGH TEMPS TDA. WENT SIGNIFICANTLY ABV GUIDANCE FOR THIS UPDATE AS MOST LOCALES SHUD EASILY PUSH INTO THE U70S. LATEST HRRR NOW HAS WIDESPREAD RAIN INTO WRN ZONES BY 22Z AND THIS WL NEED TO BE MONITORED THROUGHOUT THE DAY. PREV DISCO BLO... 155 AM UPDATE... SPRINGTIME STORM SYSTEM THAT BROUGHT SVR WX TO THE PLAINS YDA WL BE HEADED NORTHEAST OVR THE NEXT SEVERAL DAYS. WM FNT DRAPED ACRS SRN ONTARIO AND NRN NY STATE EXTENDS FM SFC LOW LOCATED OVR THE QUAD CITIES REGION. ASSOC H5 TROF IS SPINNING THRU THE CNTRL PLAINS WITH WIDESPREAD AREA OF SHOWERS/TSTMS ALONG MS RVR. ALL THIS MEANS WITH REGARD TO OUR WX IS A MILD SRLY FLOW CONTG TDA. GOM IS CURRENTLY WIDE OPEN AND DRAWING IN WARM/MOIST AIR TO CNTRL PART OF NATION WITH PW VALUES WELL ABV 1 INCH. AS TROF SLIDES EVER CLOSER TO CWA THRU THE AFTN EXPECT MOISTURE TO INCRS TO OVR 1.00 INCHES. THIS HELPS TO INCRS DWPT VALUES INTO THE 50S AND PRECLUDE FIRE WX CONCERNS FOR TDA AS OPPOSED TO YDA. IN ADDITION AN INCRS IN CLDS FM THE APPCHG SYSTEM WL SPREAD MOCLDY SKIES TO WRN ZONES DRG THE AFTN HRS WITH A HIGH THIN CIRRUS EXPECTED RMNDR OF AREA. THIS WL HELP TO TEMPER TEMP RISE TDA WITH MOST HIGHS IN THE M70S. WARM ADVECTION WL COMBINE WITH APPCHG UL FRCG AND LGT SHOWERS WL START TO DVLP ACRS THE WEST BTWN 18Z AND 21Z THIS AFTN BFR SLIDING EAST, PERHAPS GETTING AS FAR EAST AS THE I-81 CORRIDOR IN CNY BY 00Z TONIGHT. MODELS AGREE WITH PLACEMENT OF CDFNT AT 00Z TONIGHT BUT DIFFER WITH REGARD TO QPF WITH GFS MUCH MORE BULLISH THAN EURO AND NAM. WUD CERTAINLY NOT BE SURPRISED TO SEE A SPRINKLE IN CNTRL SXNS OF CWA UNDER STRONG WARM ADVECTION BUT FEEL THE CRUX OF THE PCPN WL BE FELT IN THE FINGER LKS REGION THIS AFTN. && .SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/... 4 AM UPDATE... POPS INCRS TONIGHT FM WEST TO EAST AS FRCG FM FRONT MVS CLOSER TO CWA. LKLY POPS EXPECTED BY 06Z, THEN INCRSG TO 100 POPS BY MRNG. GIVEN STRONG MOISTURE SURGE (THETA-E RIDGE) AND WARM AIR ADVECTION HV GONE WITH MORE SHOWERY MENTION THRU 09Z TONIGHT. H5 LOW WL BE SITTING UP ACRS HUDSON BAY WITH L/WV TROF BCMG NEGATIVELY TILTED TUE MRNG. 250MB SPEED MAX WL STRENGTHEN TO +120KTS BY DAYBREAK WITH CWA IN RIGHT-ENTRANCE REGION ARND 09Z, THUS WL GO WITH MORE OF A RAIN SCENARIO AFT THIS TIME. HV ADDED IN CHC FOR THUNDER DRG THE OVRNGT AS SI`S APPRCH ZERO, MLCAPES ARND 100 J/KG AND K-INDICES > 30. 00Z MODELS AGREE THAT CDFNT WL BE ENTERING INTO WRN ZONES BY 12Z TUESDAY. TEMPS WL FALL THRU THE DAY TUE IN CNY AS CDFNT COMES BLASTING THRU. MAY SEE A BRIEF RISE IN TEMPS ACRS SERN ZONES DRG THE MRNG BFR HOLDING STEADY THEN FALLING STEADILY AFT 18Z. HV SIDED MORE WITH THE TIMING OF THE CHANGEOVER FM RAIN TO SNOW/SLEET WITH THE GFS AND EURO AS NAM SEEMS TO BE TOO SLOW. EXPECT ALL RAIN DRG THE MRNG HRS AND THEN SLOWLY MIXING WITH SLEET BY EARLY AFTN ACRS THE FINGER LKS, THEN BCMG ALL SNOW AFT 21Z IN THE FINGER LKS. PCPN WL START TO MIX WITH SLEET AND SNOW AFT 21Z ACRS THE I-81 CORRIDOR IN NY STATE WITH RAIN EXPECTED THRU 00Z WED IN PIKE AND SULLIVAN CNTYS. EXPECT ALL SNOW SHOWERS TUE NGT WITH POSSIBLE EXCEPTION OF FAR SERN ZONES EARLY AS THEY TRANSITION OVR. SNOWFALL AMNTS FM TIME OF TRANSITION (LATE AFTN TUE) UNTIL PCPN EXITS STAGE RIGHT ARND 06Z WED LOOKS TO BE ON THE ORDER OF 1-1.5 INCHES. WITH H8 TEMPS PROGGED TO DROP TO NR -14C WED MRNG, EXPECT OVRNGT LOWS TO DIP INTO THE TEENS. THIS IS UNDER STRONG NW WINDS AS WELL. IF WINDS CAN DECOUPLE, TEMPS MAY DROP EVEN LOWER. THIS WUD PUT RECORD LOWS IN JEOPARDY FOR THIS DATE. KBGM`S RECORD LOW IS 24F, KAVP IS 20F AND KSYR IS 23F. UNDER FULL SUN WITH HIPRES BUILDING IN ON WED, MAX TEMPS WL QUICKLY CLIMB INTO THE 40S. HIGH WL SHIFT OFF TO THE EAST WED NGT, ALLOWING RETURN FLOW TO RE-ESTABLISH ITSELF. && .LONG TERM /THURSDAY THROUGH SUNDAY/... 315 AM UPDATE... NO MAJOR CHANGES MADE THIS MORNING AS A FAIR AMOUNT OF MODEL DISAGREEMENT STILL EXISTS WITH NEXT WEEKEND/S STORM SYSTEM. BEFORE THIS HOWEVER...DRY BUT COOLER WEATHER WILL PREVAIL THROUGH THE REMAINDER OF THE WORK WEEK AS STRONG HIGH PRESSURE REMAINS ENTRENCHED OVER THE NORTHEAST AND EASTERN CANADA. IN TERMS OF NEXT WEEKEND/S STORM SYSTEM...THE GFS TAKES A SFC LOW DIRECTLY OVER OUR FCST REGION...WHILE THE ECMWF SHOWS A SFC LOW APPROACHING FROM THE SOUTHWEST WITH THIS FEATURE GRADUALLY LOOSING STEAM AS ENERGY TRANSFERS TO A DEVELOPING COASTAL LOW OFF THE EASTERN SEABOARD. UNDER THE LATTER SCENARIO...MUCH OF OUR FCST REGION IS SPARED OF APPRECIABLE RAINFALL. FOR WHAT ITS WORTH...THE CANADIAN-CMC TOO SHOWS TRANSFERRING ENERGY ALBEIT A LITTLE FURTHER NORTH THAN THE ECMWF. IF THIS WERE TO PANE OUT AS ADVERTISED...SOME SOME PRECIP WOULD LIKELY WORK NORTH INTO OUR AREA. AS RESULT OF THIS THIRD SOLUTION...WILL MAINTAIN CHC POPS ACROSS THE SOUTHERN 2/3RDS OF THE FCST REGION FRIDAY NIGHT AND SATURDAY. PREVIOUS LONG TERM DISCUSSION... MEDIUM RANGE MODELS START OUT IN GOOD AGREEMENT EARLY IN THE EXTENDED PERIOD THEN DIVERGE BY NEXT WEEKEND. INITIALLY SFC HIGH PRES OVER NRN NEW ENGLAND AND NOVA SCOTIA WILL BRING FAIR AND COOL WEATHER TO THE AREA WITH LOWS WED NIGHT IN THE MID TO UPPER 20S FOLLOWED BY UPPER 20S TO MID 30S ON THURSDAY NIGHT. MAXES BOTH THURSDAY AND FRIDAY WILL RANGE IN THE 50S WITH SOME MODIFICATION ON FRIDAY. FRIDAY NIGHT THROUGH SUNDAY THE OPERATIONAL GFS TAKES A SFC LOW IN THE TN VALLEY AND TRACKS IT NORTHEAST ACROSS OUR VCNTY THEN INTO EASTERN CANADA BY SUNDAY. A WET SCENARIO FOLLOWED BY WRAP AROUND MOISTURE SATURDAY NIGHT INTO SUNDAY. THE ECMWF PLACES THIS FEATURE FARTHER SOUTH AND WEAKER THEN MOVES IT OFF THE MID ATLANTIC COAST KEEPING THE REGION BASICALLY DRY. FOLLOWED HPC GUIDANCE WHICH KEEPS THE SYSTEM TO OUR SOUTH BUT WILL INCLUDE CHC POPS FROM FRIDAY NIGHT THROUGH SATURDAY NIGHT FOR RAIN SHOWERS. && .AVIATION /12Z MONDAY THROUGH FRIDAY/... VFR CONDITIONS EXPECTED THROUGH THE MAJORITY OF THE FCST PERIOD AS STRONG SOUTHWEST FLOW PREVAILS AHEAD OF AN APPROACHING COLD FRONT. WINDS WILL AGAIN INCREASE AFTER SUNRISE WITH SOLID GUSTS TO NEAR/SLIGHTLY ABOVE 25 KTS THROUGH THE DAY TODAY. BEFORE THIS HOWEVER...STRONG WINDS OFF THE DECK WILL LEAD TO LOW-LEVEL WIND SHEAR AT ALL SITES UNTIL MIXING COMMENCES AFTER SUNRISE. IN TERMS OF PRECIP CHANGES...BEST POTENTIAL EXISTS AT SYR/RME/ITH/ELM AFTER 21 OR SO...WITH BEST ORGANIZED RAIN POTENTIAL HOLDING OFF UNTIL AFTER 00Z AT ALL CNY SITES. DRY CONDITIONS ANTICIPATED AT AVP THROUGH THE FCST PERIOD. AT ITH AND BGM...EXPECT DEVELOPING MVFR CIGS AFTER 00Z AS FRONTAL BOUNDARY APPROACHES. OUTLOOK... TUE...RESTRICTIONS IN SCATTERED RAIN SHOWERS AND ISOLATED THUNDER TUESDAY MORNING...WITH RAIN CHANGING TO SNOW TUE AFTERNOON/EVENING. TUE NGT...RESTRICTIONS POSSIBLE IN SCATTERED SNOW SHOWERS. WED-THU-FRI...VFR. && .FIRE WEATHER... 4 AM MONDAY UPDATE... DEWPOINT TEMPERATURES WILL REMAIN FAIRLY STEADY THROUGH THE DAY BUT TEMPERATURES ARE NOT EXPECTED TO CLIMB AS HIGH AS YESTERDAY, LEADING TO MINIMUM RELATIVE HUMIDITY VALUES REMAINING ABOVE 40% THROUGH THE DAY. SOUTH-SOUTHWEST WINDS WILL BE STRONG AND GUSTY AGAIN TODAY BUT ANY FIRE WEATHER CONCERNS WILL BE PRECLUDED BY INCREASING MOISTURE AHEAD OF AN APPROACHING COLD FRONT. WIDESPREAD RAIN WILL MOVE IN LATE TONIGHT. COLD AIR WILL MOVE IN BEHIND THE FRONT ON TUESDAY AFTERNOON, SWITCHING RAIN OVER TO SNOW SHOWERS BRIEFLY ON TUESDAY NIGHT, MAINLY ACROSS CENTRAL NEW YORK. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...NONE. && $$ SYNOPSIS...PVN NEAR TERM...PVN SHORT TERM...PVN LONG TERM...CMG/RRM AVIATION...CMG FIRE WEATHER...
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
147 AM EDT MON APR 14 2014 .SYNOPSIS... MILD AND DRY THROUGH MOST OF MONDAY. MEANWHILE...LOW PRESSURE OVER THE CENTRAL U.S. WILL MOVE NORTHEAST AND BRING SHOWERS TO AREA LATER MONDAY INTO MONDAY NIGHT. ON TUESDAY...A STRONG COLD FRONT WILL PASS THROUGH. LOCALLY HEAVY RAIN WILL BE POSSIBLE AHEAD OF THE COLD FRONT...WITH THE POTENTIAL FOR ACCUMULATING SNOWS BEHIND IT ACROSS CENTRAL NEW YORK. HIGH PRESSURE WILL BRING A RETURN TO FAIR WEATHER ON WEDNESDAY. && .NEAR TERM /THROUGH TODAY/... 1 AM UPDATE... AREA RMNS IN WM SECTOR TONIGHT WITH SRLY FLOW DRAWING IN WRMR AIR. TEMPS ARE STRUGGLING TO DROP OFF ACRS THE SRN TIER AS THEY REMAIN IN THE MID/UPR 60S. EXPECT THESE TEMPS WL ONLY DROP SVRL MORE DEGREES THRU DAYBREAK EXCEPT IN DECOUPLED VLY LOCALES, THUS HV WARMED LOWS INTO THE LWR 60S MOST LOCATIONS FOR OVRNGT MINS. NO OTHER CHGS NEEDED AT THIS TIME. PREV DISCUSSIONS BLO... 1015 PM UPDATE... ELEVATED CONVECTION IS OCCURRING NORTH OF THE SURFACE BOUNDARY AROUND THE SAINT LAWRENCE SEAWAY...SO AS EXPECTED WE ARE STAYING DRY TONIGHT. WINDS HAVE QUICKLY DECOUPLED AND SOME GRADUAL DROP OFF IN TEMPERATURES IS OCCURRING. VERY MILD REGARDLESS...WITH LOWS EXPECTED TO RANGE FROM THE MID 50S TO NEAR 60. WITH A GOOD AMOUNT OF SUNSHINE EARLIER...SINCE THE HIGH THIN CLOUDS ERADICATED MORE THAN EXPECTED...THE LOW 20S CELSIUS TEMPERATURES AT 925MB /AS HAD BEEN SUGGESTED BY RUC MODEL/ WERE ABLE TO FULLY REALIZE THEIR MIX-DOWN TEMPERATURES OF LOW 80S IN MANY LOCATIONS...THE WARMEST READINGS IN 6 MONTHS. BINGHAMTON AIRPORT DAILY RECORD HIGH IS 80 DEGREES SET IN 1977...AND IT TURNED OUT JUST 1 DEGREE SHORT OF IT TODAY. SYRACUSE AND AVOCA ALSO JUST A FEW DEGREES SHY OF DAILY RECORDS. PREVIOUS DISCUSSION... VERY MILD TEMPS TDA WITH WARM SWLY FLOW. MAY SEE AN ISOLATED -SHRA ACRS NRN ONEIDA LATE TDA OR THIS EVNG OTRW A DRY FCST. VERY MILD MINS TNGT. NXT SYSTEM APRCHS TMRW. A FEW MDLS HINT AT SOME CONVECTION ALONG A PRE-FNTL TROF OVER CNTRL NY ARND MID DAY. IN ANY EVENT...INCRSNG CHCS FOR SHRA TMRW AFTN WITH MAXES GETTING BACK INTO THE 70S MOST AREAS. TEMPS MAY FALL DURING THE AFTN WRN ZONES AS CLDS AND SCT -SHRA MOVE IN. GUSTY SSW WINDS CONTINUE ON MON. && .SHORT TERM /TONIGHT THROUGH WEDNESDAY/... VERY COMPLEX STORM SYSTEM WITH SHARP BAROCLINIC ZONE/ANAFRONT MOVS THRU ON TUE WITH WEAK SFC WAVES RIDING NE ALONG IT. TIMING OF THIS FNT ON TUE WILL BE CRITICAL TO THE FCST W/RESPECT TO CHGOVER AND +RA POTNL IN THE EAST. IN GNRL 12Z RUNS ARE SUGGESTING THAT THE TRANSITION ZONE IS BASICALLY THRU THE CWA BY 00Z WED...AND NAM/GFS SFC INDICATE RAPIDLY FALLING SNOW LVLS WITH THE FNT ON TUE. BOTTOM LINE IS THAT THERE IS ALOT OF UNCERTAINTY WITH THIS STORM...BUT TREND HAS BEEN FOR A SLIGHTLY QUICKER TIMING. WE COULD SEE PL IN THE TRANSITION ZONE BUT FOR NOW WILL JUST PLAY IT AS RAIN CHANGING TO SNOW. GIVEN A COUPLE OF VERY WARM DAYS THINK ICE POTNL FROM NAM PROFILES IS OVERDONE. WE DID LIKE THE WWD SNOW ACCUMS WITH POTNL FOR GNRLY 2-4 INCHES ON TUE AFTN/EVNG ACRS PORTIONS OF CNTRL NY. MAYBE A FEW FLURRIES SE OF LAKE ONTARIO ON TUE NGT...WITH LAKE CLDS LIKELY SE OF LAKE ONTARIO ON WED MRNG IN NWLY FLOW. MUCH COOLER WITH MAXES ONLY U30S TO L40S. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... MEDIUM RANGE MODELS START OUT IN GOOD AGREEMENT EARLY IN THE EXTENDED PERIOD THEN DIVERGE BY NEXT WEEKEND. INITIALLY SFC HIGH PRES OVER NRN NEW ENGLAND AND NOVA SCOTIA WILL BRING FAIR AND COOL WEATHER TO THE AREA WITH LOWS WED NIGHT IN THE MID TO UPPER 20S FOLLOWED BY UPPER 20S TO MID 30S ON THURSDAY NIGHT. MAXES BOTH THURSDAY AND FRIDAY WILL RANGE IN THE 50S WITH SOME MODIFICATION ON FRIDAY. FRIDAY NIGHT THROUGH SUNDAY THE OPERATIONAL GFS TAKES A SFC LOW IN THE TN VALLEY AND TRACKS IT NORTHEAST ACROSS OUR VCNTY THEN INTO EASTERN CANADA BY SUNDAY. A WET SCENARIO FOLLOWED BY WRAP AROUND MOISTURE SATURDAY NIGHT INTO SUNDAY. THE ECMWF PLACES THIS FEATURE FARTHER SOUTH AND WEAKER THEN MOVES IT OFF THE MID ATLANTIC COAST KEEPING THE REGION BASICALLY DRY. FOLLOWED HPC GUIDANCE WHICH KEEPS THE SYSTEM TO OUR SOUTH BUT WILL INCLUDE CHC POPS FROM FRIDAY NIGHT THROUGH SATURDAY NIGHT FOR RAIN SHOWERS. && .AVIATION /06Z MONDAY THROUGH FRIDAY/... VFR CONDITIONS EXPECTED THROUGH THE MAJORITY OF THE FCST PERIOD AS STRONG SOUTHWEST FLOW PREVAILS AHEAD OF AN APPROACHING COLD FRONT. WINDS WILL AGAIN INCREASE AFTER SUNRISE WITH SOLID GUSTS TO NEAR/SLIGHTLY ABOVE 25 KTS THROUGH THE DAY TODAY. BEFORE THIS HOWEVER...STRONG WINDS OFF THE DECK WILL LEAD TO LOW-LEVEL WIND SHEAR AT ALL SITES UNTIL MIXING COMMENCES AFTER SUNRISE. IN TERMS OF PRECIP CHANGES...BEST POTENTIAL EXISTS AT SYR/RME/ITH/ELM AFTER 21 OR SO...WITH BEST ORGANIZED RAIN POTENTIAL HOLDING OFF UNTIL AFTER 00Z AT ALL CNY SITES. DRY CONDITIONS ANTICIPATED AT AVP THROUGH THE FCST PERIOD. AT ITH AND BGM...EXPECT DEVELOPING MVFR CIGS AFTER 00Z AS FRONTAL BOUNDARY APPROACHES. OUTLOOK... TUE...RESTRICTIONS IN SCATTERED RAIN SHOWERS AND ISOLATED THUNDER TUESDAY MORNING...WITH RAIN CHANGING TO SNOW TUE AFTERNOON/EVENING. TUE NGT...RESTRICTIONS POSSIBLE IN SCATTERED SNOW SHOWERS. WED-THU-FRI...VFR. && .FIRE WEATHER... 1015 PM SUNDAY UPDATE... CONDITIONS APPROACHED CRITICAL VALUES SUNDAY AFTERNOON BUT WINDS HAVE BACKED OFF CONSIDERABLY THIS EVENING ALONG WITH RECOVERING RELATIVE HUMIDITY ALREADY IN THE 40S-50S PCT RANGE AT 10 PM. FAIRLY WARM WITH STOUT SOUTH-SOUTHWEST WINDS AGAIN MONDAY...BUT WITH HIGHER HUMIDITY VALUES AS MOISTURE INCREASES AHEAD OF APPROACHING COLD FRONT. MINIMUM HUMIDITY VALUES MONDAY...VERSUS WHAT WE JUST HAD SUNDAY AFTERNOON...WILL BE A GOOD 15 TO 25 PERCENT HIGHER. RAIN CHANCES INCREASING LATE MONDAY THROUGH MONDAY NIGHT...LEADING TO A SOLID WETTING RAIN TUESDAY WITH FALLING TEMPERATURES. EVEN SOME CHANGEOVER TO SNOW TUESDAY AFTERNOON- EVENING /ESPECIALLY CENTRAL NY/. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...NONE. && $$ SYNOPSIS...MDP NEAR TERM...MDP/PVN SHORT TERM... LONG TERM...RRM AVIATION...CMG FIRE WEATHER...
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
105 AM EDT MON APR 14 2014 .SYNOPSIS... MILD AND DRY THROUGH MOST OF MONDAY. MEANWHILE...LOW PRESSURE OVER THE CENTRAL U.S. WILL MOVE NORTHEAST AND BRING SHOWERS TO AREA LATER MONDAY INTO MONDAY NIGHT. ON TUESDAY...A STRONG COLD FRONT WILL PASS THROUGH. LOCALLY HEAVY RAIN WILL BE POSSIBLE AHEAD OF THE COLD FRONT...WITH THE POTENTIAL FOR ACCUMULATING SNOWS BEHIND IT ACROSS CENTRAL NEW YORK. HIGH PRESSURE WILL BRING A RETURN TO FAIR WEATHER ON WEDNESDAY. && .NEAR TERM /THROUGH TODAY/... 1 AM UPDATE... AREA RMNS IN WM SECTOR TONIGHT WITH SRLY FLOW DRAWING IN WRMR AIR. TEMPS ARE STRUGGLING TO DROP OFF ACRS THE SRN TIER AS THEY REMAIN IN THE MID/UPR 60S. EXPECT THESE TEMPS WL ONLY DROP SVRL MORE DEGREES THRU DAYBREAK EXCEPT IN DECOUPLED VLY LOCALES, THUS HV WARMED LOWS INTO THE LWR 60S MOST LOCATIONS FOR OVRNGT MINS. NO OTHER CHGS NEEDED AT THIS TIME. PREV DISCUSSIONS BLO... 1015 PM UPDATE... ELEVATED CONVECTION IS OCCURRING NORTH OF THE SURFACE BOUNDARY AROUND THE SAINT LAWRENCE SEAWAY...SO AS EXPECTED WE ARE STAYING DRY TONIGHT. WINDS HAVE QUICKLY DECOUPLED AND SOME GRADUAL DROP OFF IN TEMPERATURES IS OCCURRING. VERY MILD REGARDLESS...WITH LOWS EXPECTED TO RANGE FROM THE MID 50S TO NEAR 60. WITH A GOOD AMOUNT OF SUNSHINE EARLIER...SINCE THE HIGH THIN CLOUDS ERADICATED MORE THAN EXPECTED...THE LOW 20S CELSIUS TEMPERATURES AT 925MB /AS HAD BEEN SUGGESTED BY RUC MODEL/ WERE ABLE TO FULLY REALIZE THEIR MIX-DOWN TEMPERATURES OF LOW 80S IN MANY LOCATIONS...THE WARMEST READINGS IN 6 MONTHS. BINGHAMTON AIRPORT DAILY RECORD HIGH IS 80 DEGREES SET IN 1977...AND IT TURNED OUT JUST 1 DEGREE SHORT OF IT TODAY. SYRACUSE AND AVOCA ALSO JUST A FEW DEGREES SHY OF DAILY RECORDS. PREVIOUS DISCUSSION... VERY MILD TEMPS TDA WITH WARM SWLY FLOW. MAY SEE AN ISOLATED -SHRA ACRS NRN ONEIDA LATE TDA OR THIS EVNG OTRW A DRY FCST. VERY MILD MINS TNGT. NXT SYSTEM APRCHS TMRW. A FEW MDLS HINT AT SOME CONVECTION ALONG A PRE-FNTL TROF OVER CNTRL NY ARND MID DAY. IN ANY EVENT...INCRSNG CHCS FOR SHRA TMRW AFTN WITH MAXES GETTING BACK INTO THE 70S MOST AREAS. TEMPS MAY FALL DURING THE AFTN WRN ZONES AS CLDS AND SCT -SHRA MOVE IN. GUSTY SSW WINDS CONTINUE ON MON. && .SHORT TERM /TONIGHT THROUGH WEDNESDAY/... VERY COMPLEX STORM SYSTEM WITH SHARP BAROCLINIC ZONE/ANAFRONT MOVS THRU ON TUE WITH WEAK SFC WAVES RIDING NE ALONG IT. TIMING OF THIS FNT ON TUE WILL BE CRITICAL TO THE FCST W/RESPECT TO CHGOVER AND +RA POTNL IN THE EAST. IN GNRL 12Z RUNS ARE SUGGESTING THAT THE TRANSITION ZONE IS BASICALLY THRU THE CWA BY 00Z WED...AND NAM/GFS SFC INDICATE RAPIDLY FALLING SNOW LVLS WITH THE FNT ON TUE. BOTTOM LINE IS THAT THERE IS ALOT OF UNCERTAINTY WITH THIS STORM...BUT TREND HAS BEEN FOR A SLIGHTLY QUICKER TIMING. WE COULD SEE PL IN THE TRANSITION ZONE BUT FOR NOW WILL JUST PLAY IT AS RAIN CHANGING TO SNOW. GIVEN A COUPLE OF VERY WARM DAYS THINK ICE POTNL FROM NAM PROFILES IS OVERDONE. WE DID LIKE THE WWD SNOW ACCUMS WITH POTNL FOR GNRLY 2-4 INCHES ON TUE AFTN/EVNG ACRS PORTIONS OF CNTRL NY. MAYBE A FEW FLURRIES SE OF LAKE ONTARIO ON TUE NGT...WITH LAKE CLDS LIKELY SE OF LAKE ONTARIO ON WED MRNG IN NWLY FLOW. MUCH COOLER WITH MAXES ONLY U30S TO L40S. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... MEDIUM RANGE MODELS START OUT IN GOOD AGREEMENT EARLY IN THE EXTENDED PERIOD THEN DIVERGE BY NEXT WEEKEND. INITIALLY SFC HIGH PRES OVER NRN NEW ENGLAND AND NOVA SCOTIA WILL BRING FAIR AND COOL WEATHER TO THE AREA WITH LOWS WED NIGHT IN THE MID TO UPPER 20S FOLLOWED BY UPPER 20S TO MID 30S ON THURSDAY NIGHT. MAXES BOTH THURSDAY AND FRIDAY WILL RANGE IN THE 50S WITH SOME MODIFICATION ON FRIDAY. FRIDAY NIGHT THROUGH SUNDAY THE OPERATIONAL GFS TAKES A SFC LOW IN THE TN VALLEY AND TRACKS IT NORTHEAST ACROSS OUR VCNTY THEN INTO EASTERN CANADA BY SUNDAY. A WET SCENARIO FOLLOWED BY WRAP AROUND MOISTURE SATURDAY NIGHT INTO SUNDAY. THE ECMWF PLACES THIS FEATURE FARTHER SOUTH AND WEAKER THEN MOVES IT OFF THE MID ATLANTIC COAST KEEPING THE REGION BASICALLY DRY. FOLLOWED HPC GUIDANCE WHICH KEEPS THE SYSTEM TO OUR SOUTH BUT WILL INCLUDE CHC POPS FROM FRIDAY NIGHT THROUGH SATURDAY NIGHT FOR RAIN SHOWERS. && .AVIATION /05Z MONDAY THROUGH FRIDAY/... 00Z UPDATE... VFR CONDITIONS GENERALLY EXPECTED THROUGH 00Z TUESDAY...BUT SCATTERED SHOWERS AND PERHAPS ISOLATED THUNDERSTORMS COULD BE MOVING INTO THE WESTERN TERMINALS /KSYR-KITH-KELM AND MAYBE KRME/ 21Z MON-00Z TUE. THIS WILL BE WITH INCREASING MOISTURE AND INSTABILITY AHEAD OF AN APPROACHING COLD FRONT...WHICH WILL NOT PASS UNTIL TUESDAY. WINDS DECOUPLING AND DIMINISHING THIS EVENING NEAR THE SURFACE...YET STILL STRONG FROM THE SSW AS A 40-50 KT JET DEVELOPS AT 1500-2000 FT AGL...RESULTING IN LLWS CONDITIONS OVERNIGHT. LLWS THEN BECOMES A NON-ISSUE SHORTLY AFTER 12Z AS WINDS MANAGE TO MIX DOWN BETTER TO THE SURFACE WITH DAYTIME HEATING. DURING THE DAY MONDAY...SURFACE WIND SUSTAINED MID TEENS WITH GUSTS IN 25-30 KT RANGE...FROM SSW DIRECTION. OUTLOOK... MON NGT-TUE...RESTRICTIONS IN SCATTERED RAIN SHOWERS AND ISOLATED THUNDER MONDAY NIGHT TO TUESDAY MORNING...THEN RAIN CHANGING TO SNOW TUE AFTERNOON-EVENING. TUE NGT...RESTRICTIONS POSSIBLE IN SCATTERED SNOW SHOWERS. WED-THU-FRI...VFR. && .FIRE WEATHER... 1015 PM SUNDAY UPDATE... CONDITIONS APPROACHED CRITICAL VALUES SUNDAY AFTERNOON BUT WINDS HAVE BACKED OFF CONSIDERABLY THIS EVENING ALONG WITH RECOVERING RELATIVE HUMIDITY ALREADY IN THE 40S-50S PCT RANGE AT 10 PM. FAIRLY WARM WITH STOUT SOUTH-SOUTHWEST WINDS AGAIN MONDAY...BUT WITH HIGHER HUMIDITY VALUES AS MOISTURE INCREASES AHEAD OF APPROACHING COLD FRONT. MINIMUM HUMIDITY VALUES MONDAY...VERSUS WHAT WE JUST HAD SUNDAY AFTERNOON...WILL BE A GOOD 15 TO 25 PERCENT HIGHER. RAIN CHANCES INCREASING LATE MONDAY THROUGH MONDAY NIGHT...LEADING TO A SOLID WETTING RAIN TUESDAY WITH FALLING TEMPERATURES. EVEN SOME CHANGEOVER TO SNOW TUESDAY AFTERNOON- EVENING /ESPECIALLY CENTRAL NY/. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...NONE. && $$ SYNOPSIS...MDP NEAR TERM...MDP/PVN SHORT TERM... LONG TERM...RRM AVIATION...MDP FIRE WEATHER...
AREA FORECAST DISCUSSION
NWS RALEIGH NC
302 PM EDT MON APR 14 2014 .SYNOPSIS...A WARM MOIST SOUTHERLY FLOW WILL INCREASE OVER THE AREA THROUGH TONIGHT. A COLD FRONT WILL APPROACH THE MOUNTAINS FROM THE WEST LATE TONIGHT... THEN PROGRESS EAST ACROSS THE CAROLINAS TUESDAY AFTERNOON AND EVENING. COOL HIGH PRESSURE WILL EXTEND INTO THE AREA FROM THE NORTH WEDNESDAY THROUGH THURSDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 300 PM MONDAY... AS PRECIPITABLE WATER VALUES HAVE CLIMBED TO NEAR AN INCH...AND INSTABILITY HAS INCREASED DURING THE DAY WITH MSAS SHOWING LIFTED INDICES AROUND -2C AND MLCAPE ON THE SPC MESOANALYSIS A COUPLE OF HUNDRED J/KG...A FEW SHOWERS HAVE DEVELOPED OVER THE PIEDMONT IN UPPER DIFFLUENCE AS A MODEST MID-LEVEL SHORTWAVE MOVES THROUGH. THE LATEST HRRR WRF IS HANDLING THE LOCATION...COVERAGE...AND INTENSITY OF THESE SHOWERS FAIRLY WELL...AND THOUGH AN ISOLATED THUNDERSTORM IS POSSIBLE...MOSTLY THE RELATIVELY DEEP CONVECTION SHOULD REMAIN AS SHOWERS. OVERNIGHT...A GRADUAL INCREASE IN MOISTURE CONTINUES...WITH PRECIPITABLE WATER VALUES INCREASING TO NEAR 1.5 INCHES BY 12Z TUESDAY AS 850MB THETA-E VALUES INCREASE AS WELL. MID-LEVEL SHORTWAVES MOVING TOWARD CENTRAL NORTH CAROLINA SHOULD WEAKEN AS THEY APPROACH...AND THE NAM IN PARTICULAR FORECASTS 850MB LIFT TO DECREASE...BUT 850MB WINDS INCREASE LATE TONIGHT WHICH SHOULD ADD TO MOISTURE TRANSPORT AND LIFT...AND 0-3KM SHEAR INCREASES AS WELL TO AROUND 40KT PARTICULARLY IN THE SOUTHWEST PIEDMONT LATE. ALREADY... THE COVERAGE OF SHOWERS HAS INCREASED TOWARD THE FOOTHILLS...AND GRADUALLY DURING THE EVENING AND OVERNIGHT HOURS THE COVERAGE OF NUMEROUS OR GREATER SHOWERS AND ISOLATED THUNDERSTORMS SHOULD MOVE EAST ACROSS CENTRAL NORTH CAROLINA. THROUGH MIDNIGHT...THE AREA WITH BETTER COVERAGE OF SHOWERS SHOULD BE OVER THE FAR WESTERN PIEDMONT...THEN OVERNIGHT...EXPECT BETTER COVERAGE GRADUALLY EASTWARD. AS WINDS ALOFT INCREASE...AN ISOLATED STRONG STORM CANNOT BE RULED OUT...ESPECIALLY OVER THE SOUTHWEST PIEDMONT WHERE THE COMBINATION OF SHEAR AND 850MB WINDS AND LIFT IS EXPECTED TO BE BEST OVERNIGHT. ALSO...IT IS INTERESTING THAT THE NAM MOS GUIDANCE FORECASTS SUSTAINED WINDS TO 25KT AT KGSO AND EVEN THE GFS FORECASTS SUSTAINED SURFACE WINDS TO JUST BELOW 20KT LATE TONIGHT. A FEW DECENT GUSTS ARE POSSIBLE...IT WOULD SEEM...AS ANY HEAVIER SHOWER MOVES THROUGH OVERNIGHT. AROUND AND JUST AFTER 06Z... THE GFS BUFR SOUNDINGS SHOW A MOIST ADIABATIC PROFILE AT KGSO WITH WINDS JUST OFF THE SURFACE TO 40KT...AND THE NAM...WHILE DRIER...DOES HAVE A SLIGHTLY STEEPER LAPSE RATE. OVERNIGHT LOWS SHOULD BE WARM...IN THE LOWER TO MID 60S AHEAD OF THE FRONT. && .SHORT TERM /TUESDAY AND TUESDAY NIGHT/... AS OF 300 PM MONDAY... WEAKENING LIFT BUT WITH INCREASING 0-3KM SHEAR MOVES EAST ACROSS CENTRAL NORTH CAROLINA EARLY TUESDAY...THEN THERE IS FORECAST A BRIEF RESPITE IN THE CHANCES FOR SHOWERS AROUND MID-MORNING WITH A SLIGHT DECREASE IN 850MB THETA-E VALUES AND INSTABILITY. AS THE AFTERNOON APPROACHES...850MB WINDS SHOULD INCREASE TO 50 TO 55KT AS A 120KT 300MB JET MOVES THROUGH THE AREA...COINCIDENT WITH THE RIGHT ENTRANCE REGION OF A 90KT 500MB JET. WHILE 1000-500MB LAPSE RATES ARE ONLY FORECAST AROUND 6C/KM...AND THOSE MAINLY EAST OF U.S. 1... MUCAPE THAT INCREASES OVERNIGHT TO NEARLY 1000J/KG ON THE NAM OVER THE FAR SOUTHWEST PIEDMONT CONTINUES TO PUSH ACROSS CENTRAL NORTH CAROLINA WITH VALUES FROM 1000-1500J/KG DURING TUESDAY. 0-3KM SHEAR IS ON THE ORDER OF 40-50KT TUESDAY AFTERNOON...INCREASING FURTHER TOWARD THE INTERSTATE 95 CORRIDOR LATE. MODEST LAPSE RATES IN A BROADLY MOIST AIR MASS SHOULD HELP TO LIMIT AVAILABLE INSTABILITY... BUT SYSTEM DYNAMICS ALONG AND AHEAD OF THE FRONT COULD COMPENSATE FOR THIS AND MAKE FOR THE POTENTIAL FOR ISOLATED SEVERE STORMS TUESDAY. IF A LOCATION SEEMED TO HAVE A BETTER CHANCE OF ISOLATED SEVERE STORMS...IT WOULD SEEM TO BE ALONG AND EAST OF U.S. 1 WHERE THE OVERALL INSTABILITY AND SHEAR WILL BE BETTER TUESDAY AFTERNOON...AS LIFTED INDICES THERE SHOULD BE -2C TO -4C...WITH BETTER HEATING EXPECTED. THE PRIMARY SEVERE THREAT IS ANTICIPATED TO BE WIND...BUT WITH 0-3KM HELICITY VALUES FROM 100-300 M2/S2...AN ISOLATED TORNADO CANNOT BE RULED OUT. HIGHS WERE LEANED TOWARD THE WARMER MAV GUIDANCE ANTICIPATING A BREAK IN PRECIPITATION DURING THE MORNING...UPPER 60S NORTHWEST TO AROUND 80 SOUTHEAST. STRONG COLD AIR ADVECTION TAKES PLACE TUESDAY NIGHT AS HIGH PRESSURE MOVES IN. ONCE THE STRONG MID-LEVEL TROUGH MOVES THROUGH THE THREAT OF PRECIPITATION SHOULD END...THEN IMPACTS TURN TOWARD THE POTENTIAL FOR FREEZING CONDITIONS. THE GUIDANCE HAS BEEN CONSISTENT FORECASTING LOWS AT OR BELOW FREEZING FOR A COUPLE OF RUNS MAINLY ALONG AND WEST OF INTERSTATE 95...AND WHILE WINDS IN MANY LOCATIONS SHOULD STAY UP THROUGH A LARGE PART OF THE NIGHT IN A TIGHT GRADIENT BEHIND THE COLD FRONT AS THE HIGH BUILDS IN...LATE AT NIGHT THERE SHOULD BE JUST ENOUGH WIND REDUCTION IN COMBINATION WITH SIMPLE ADVECTION TO RESULT IN SEVERAL AREAS WITH TEMPERATURES BELOW FREEZING. WILL ISSUE A FREEZE WATCH FOR A LARGE PART OF CENTRAL NORTH CAROLINA FOR TUESDAY NIGHT INTO EARLY WEDNESDAY MORNING... KEEPING OUT THE IMMEDIATE INTERSTATE 95 CORRIDOR FOR NOW DUE TO GREATER WIND AND MIXING EXPECTED THERE. LOWS TUESDAY NIGHT 29 TO 32 MOSTLY FROM U.S. 1 WEST...33 TO 37 IN THE INTERSTATE 95 CORRIDOR. && .LONG TERM /WEDNESDAY THROUGH MONDAY/... AS OF 300 PM MONDAY... FOR WED THROUGH THU NIGHT: THE INTENSE BUT DAMPENING TROUGH WILL TRACK QUICKLY TO OUR NORTHEAST IN THE PREDAWN HOURS WED...AND WILL BE FOLLOWED BY GENERALLY FLAT SW FLOW OVER THE SOUTHEAST/MIDSOUTH/ CAROLINAS THROUGH WED. FORECAST SOUNDINGS ARE VERY DRY AND STABLE AS THE CENTER OF THE COOL SURFACE HIGH PRESSURE MOVES FROM THE OHIO VALLEY NORTHEASTWARD OVER THE ST LAWRENCE VALLEY WHILE NOSING DOWN THROUGH NC. EXPECT BREEZY AND COOL WINDS FROM THE NE WED... DIMINISHING LATE WED INTO THU AS THE MSLP GRADIENT RELAXES. LOW LEVEL THICKNESSES ARE EXPECTED TO PLUNGE TUE NIGHT TO OVER 70 M BELOW NORMAL...WITH ONLY MODEST RECOVERY DURING THE DAY... TRANSLATING TO HIGHS IN THE LOW-MID 50S. (AND THIS MAY EVEN BE OPTIMISTIC CONSIDERING THE PROJECTED 925 MB TEMPS BROUGHT DOWN DRY ADIABATICALLY YIELD HIGHS ONLY AROUND 50 OVER MUCH OF CENTRAL NC.) EXPECT MOSTLY CLEAR SKIES TO CONTINUE THROUGH THU NIGHT WITH DEEP DRY/STABLE AIR AS THE SLOWLY RETREATING AND MODIFYING SURFACE RIDGE NOSES INTO NC FROM THE NORTH... ALTHOUGH WE COULD START TO SEE PATCHY STRATUS LATE THU NIGHT WITH INCREASING ONSHORE-DIRECTED FLOW. LIGHT WINDS AND A CONTINUED ANOMALOUSLY COOL AIR MASS WILL FOSTER GOOD RADIATIONAL COOLING CONDITIONS... AND ANOTHER LIGHT FREEZE IS POSSIBLE WED NIGHT... PARTICULARLY IN THE RURAL AREAS OF THE PIEDMONT. NOT QUITE AS COOL THU WITH HIGHS EXPECTED TO BE 59-64. LOWS THU NIGHT 37-42 WITH RISING DEW POINTS. FOR FRI THROUGH MON: LONGWAVE TROUGHING THAT DRIFTS EAST ACROSS CENTRAL NOAM THU IS EXPECTED TO AMPLIFY SLIGHTLY AS IT HEADS EASTWARD INTO ERN NOAM FRI/SAT. THE APPROACH OF THIS TROUGH IS EXPECTED TO DRAW ENERGY FROM THE NRN GULF TOWARD THE NE... INDUCING SURFACE CYCLOGENESIS OVER THE NE GULF OR FL... WHICH WOULD THEN TRACK NORTHEASTWARD OVER OR JUST OFF THE SOUTHEAST COAST FRI NIGHT/SAT. THE GFS IS FAIRLY DRY HERE... HOLDING ITS SRN STREAM PRECIP TO OUR SE AND ANY NRN STREAM PRECIP TO OUR NORTH. THE ECMWF IS STRONGER WITH THE SOUTHERN WAVE... DEEPENING IT OVER SRN GA AND FL... BUT IT TOO HOLDS MOST OF THE PRECIP WITH THIS WAVE TO OUR SE. WILL RETAIN THE BASIC STRUCTURE OF THE PRECIP CHANCES WE CURRENTLY HAVE IN THERE... BUT REDUCE THEM AND CONFINE THE BETTER POPS TO OUR SOUTHEAST SECTIONS. AFTER BOTH THE NORTHERN AND SOUTHERN TROUGHS SHIFT EAST OF OUR LONGITUDE LATE SAT INTO SAT NIGHT... MID LEVEL RIDGING OVERSPREADS THE GULF/MIDSOUTH INTO THE SOUTHEAST AS ANOTHER HIGH PRESSURE BRIEFLY BUILDS IN FROM THE NORTH ON SUNDAY. EXPECT DECREASING CLOUDS SAT NIGHT AND A GOOD BIT OF SUNSHINE EASTER SUNDAY WITH MODERATING TEMPS CLOSE TO SEASONAL NORMALS. LOW CONFIDENCE IN MONDAY`S FORECAST AS THE GFS DEEPENS A MID LEVEL LOW OVER THE LOWER GREAT LAKES... LEADING TO SURFACE LOW FORMATION ALONG A ROUGHLY E-W FRONT ACROSS THE REGION WITH WIDESPREAD RAIN MOVING IN... WHILE THE ECMWF IS MUCH WEAKER/SLOWER AND KEEPS NC DRY MON. WILL GO WITH THE WEAKER ECMWF SOLUTION AND KEEP MONDAY DRY FOR NOW... BUT STAY TUNED. EXPECT TEMPS CLOSE TO NORMAL MON. && .AVIATION /18Z MONDAY THROUGH SATURDAY/... AS OF 155 PM MONDAY... ASIDE FROM A THREAT OF BKN MVFR CIGS NEAR INT/GSO EARLY IN THE TAF PERIOD FROM 18Z-20Z TODAY... A PERIOD OF CONTINUED PREVAILING VFR CONDITIONS EXPECTED THIS AFTERNOON INTO EARLY EVENING (THROUGH AROUND 02Z OR 03Z)... WITH WINDS FROM THE SOUTH AT 8-15 KTS SPORADICALLY GUSTING TO 15-20 KTS... AND VFR CIGS. PATCHY SHOWERS MAY OCCUR PRIMARILY AT FAY... BUT ARE UNLIKELY TO LAST ANY MORE THAN 15 MIN AT ANY ONE TIME. AVIATION CONDITIONS ARE EXPECTED TO DETERIORATE THIS EVENING... AROUND 02Z OR 03Z... WITH CIGS DROPPING TO MVFR THEN FAIRLY QUICKLY TO IFR IN THE 04Z-06Z TIME FRAME... WITH CONTINUED STOUT WINDS FROM THE SOUTH AND SSW (FROM 180-210 DEGREES) STRENGTHENING TO AROUND 14-17 KTS GUSTING TO 20-25 KTS OVERNIGHT. EXPECT ON-AND-OFF MAINLY MVFR-VSBY-PRODUCING SHOWERS FROM THIS 04Z- 06Z TIME FRAME THROUGH AROUND 11Z-13Z. WINDS WILL REMAIN BLUSTERY FROM THE SSW THROUGH THE END OF THE TAF VALID PERIOD... POTENTIALLY INDUCING MECHANICAL TURBULENCE... BUT A LULL IN SHOWERS IS THEN EXPECTED FROM THIS 11Z-13Z WINDOW LASTING A FEW HOURS. CIGS MAY RISE A BIT TO MVFR DURING THIS RELATIVE LULL IN PRECIP. HOWEVER... AS A STRONG COLD FRONT APPROACHES FROM THE WEST... INT/GSO MAY SEE WIDESPREAD SHOWERS/STORMS MOVING IN TOWARD THE END OF THE TAF VALID PERIOD (AFTER 16Z). LOOKING BEYOND 18Z TUE: WIDESPREAD SHOWERS AND STORMS GENERATING IFR CONDITIONS WILL SPREAD WEST TO EAST ACROSS CENTRAL NC FROM 18Z THROUGH 06Z... AS A STRONG COLD FRONT CROSSES THE STATE. STRONG WINDS FROM THE SSW AND SW WILL SHIFT ABRUPTLY TO BE FROM THE NW TUE AFTERNOON. HIGH CONFIDENCE IN CLEARING SKIES AND VFR CONDITIONS POST- FRONT AFTER MIDNIGHT TUE NIGHT LASTING THROUGH THU EVENING. THERE IS A CHANCE OF SHALLOW LOW STRATUS LATE THU NIGHT/EARLY FRI MORNING... THEN A BETTER CHANCE OF THICKER LOW STRATUS FRI NIGHT THROUGH NOON SAT AHEAD OF THE NEXT STORM SYSTEM MOVING IN FROM THE SOUTH. -GIH && .CLIMATE... THE FOLLOWING ARE THE RECORD LOW TEMPERATURES FOR WED AND THU MORNING... AND THE RECORD LOW MAXIMUM TEMPERATURES FOR WED: WED 04/16 THU 04/17 LOW/YEAR LOW MAX/YEAR LOW/YEAR FAY: 28/1943 56/1950 31/1953 GSO: 25/1943 48/1929 29/1953 RDU: 28/1950 46/1890 29/1962 && .RAH WATCHES/WARNINGS/ADVISORIES... FREEZE WATCH FROM LATE TUESDAY NIGHT THROUGH WEDNESDAY MORNING FOR NCZ007>010-021>026-038>041-073>077-083-084. && $$ SYNOPSIS...HARTFIELD NEAR TERM...DJF SHORT TERM...DJF LONG TERM...HARTFIELD AVIATION...HARTFIELD CLIMATE...MWS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
155 PM EDT MON APR 14 2014 .SYNOPSIS...A WARM MOIST SOUTHERLY FLOW WILL INCREASE OVER THE AREA THROUGH TONIGHT. A COLD FRONT WILL APPROACH THE MOUNTAINS FROM THE WEST LATE TONIGHT... THEN PROGRESS EAST ACROSS THE CAROLINAS TUESDAY AFTERNOON AND EVENING. COOL HIGH PRESSURE WILL EXTEND INTO THE AREA FROM THE NORTH WEDNESDAY THROUGH THURSDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1055 AM MONDAY... THE 12Z KGSO SOUNDING WAS CAPPED TO DEEP CONVECTION WITH A GOOD CAP BETWEEN 850MB AND 700MB...AND CONSIDERABLE MOISTURE ABOVE 500MB. THE LATEST SPC MESOANALYSIS SHOWED A RELATIVE MINIMUM OF PRECIPITABLE WATER VALUES OVER MUCH OF CENTRAL NORTH CAROLINA ALTHOUGH WITH A NARROW RIBBON OF INCREASING VALUES...JUST BELOW AN INCH...EXTENDING FROM SOUTH CAROLINA INTO THE SOUTHWEST PIEDMONT. HIGH PRESSURE EXTENDING OVER CENTRAL NORTH CAROLINA FROM THE EAST WAS PROVIDING A MOIST...SOUTHERLY FLOW OFF OF THE ATLANTIC INTO THE AREA...WITH SURFACE DEW POINTS IN THE MID 50S TO AROUND 60. TO OUR WEST...THE SURFACE LOW WILL INCREASE IN STRENGTH DUE TO THE OFFSET UPPER LEVEL TROUGH TO THE WEST. DIVERGENCE ALOFT IS DECREASING THE SURFACE PRESSURE AHEAD OF THE FRONT BRINGING IN CYCLONIC VORTICITY ADVECTION IN A SHORT WAVE AHEAD OF THE FRONT. SURFACE WINDS ARE SOUTHERLY AND HAVE INCREASED THE DEWPOINTS AS MOIST AND WARM AIR IS ADVECTED INTO THE AREA AHEAD OF THE COLD FRONT. WARM ADVECTION ALONG WITH CYCLONIC VORTICITY ADVECTION WILL BRING AN INCREASE IN LIFT AND CLOUD COVER OVER THE AREA AND AN INCREASED CHANCE FOR PRECIPITATION AND CONVECTION. A FEW SHOWERS ARE POPPING UP TO OUR WEST AND ARE EXPECTED TO INCREASE IN NUMBER AND EVENTUALLY PRODUCE CONVECTIVE STORMS AS THE COLD FRONT MOVES EASTWARD. THE 12Z UPPER-AIR ANALYSIS SHOWED SOME DIFFLUENCE TO OUR WEST AND THIS IS FORECAST TO CONTINUE THIS AFTERNOON INTO TONIGHT AS A SERIES OF MID-LEVEL WAVES MOVE THROUGH CENTRAL NORTH CAROLINA. THE LATEST RAP SHOWS THE MID-LEVEL CAP WEAKENING WITH TIME THROUGH EARLY AFTERNOON...AND SLIGHT 700MB COOLING ON THE 12Z UPPER-AIR ANALYSIS WOULD SUGGEST THIS...ALTHOUGH THE RAP ALSO FORECASTS A MODEST INCREASE IN THOSE MID-LEVEL TEMPERATURES LATE IN THE DAY. WITH THE MOISTURE IN PLACE...MODEST INSTABILITY WITH SURFACE-BASED CAPE AROUND 400J/KG AND MLCAPE IN THHIGHS TODAY WERE LOWERED ABOUT A DEGREE IN THE TRIAD DUE TO EXPECTED CLOUD COVER...AND RAISED ABOUT A DEGREE TOWARD INTERSTATE 95 DUE TO THINNER CLOUDS FOR A LONGER PERIOD OF TIME THERE. E LOWEST KM AROUND 200J/KG...AND SOME LIFT WITH THE MID-LEVEL SHORTWAVES...AS THE CAP ERODES ANTICIPATE ISOLATED TO SCATTERED SHOWERS DEVELOPING...WITH AN ISOLATED THUNDERSTORM POSSIBLE. AS THE MID-LEVEL TEMPERATURES WARM SLIGHTLY LATER...THIS COULD FOR A TIME INHIBIT MORE DEEP CONVECTION...AND THIS SCENARIO IS NOTED BY MORE THAN ONE WRF MODEL AS WELL AS IMPLIED BY RAP QPF. MOISTENING OF THE UPPER LEVELS WILL INCREASE CLOUD DEPTH AND ALLOW FOR LIFTING OVER A DEEPER LAYER. THIS WILL INCREASE THE CHANCE FOR SOME DEEP MOIST CONVECTION AND SHOWERS OVER THE AREA... HOWEVER...THE STRONGEST LIFTING WILL STAY TO THE WEST WITH THE COLD FRONT. CONVECTION SHOULD BECOME MORE NUMEROUS IN COVERAGE OVER CENTRAL NORTH CAROLINA THIS EVENING INTO TONIGHT DUE TO ONGOING MOISTENING...STRENGTHENING HEIGHT FALLS...AND PERIODIC DPVA IN SW FLOW ALOFT...ESPECIALLY IN WESTERN PORTIONS OF THE STATE. HOWEVER...SEVERAL LARGE MESOSCALE CONVECTIVE SYSTEMS ARE EXPECTED TO DEVELOP UPSTREAM IN THE DEEP SOUTH IN THIS PERIOD...ONE THIS AFTERNOON AND PERHAPS ANOTHER LATE TONIGHT...AND HOW THESE FEATURES EVOLVE/INTERACT WITH THE LARGER SCALE PATTERN WILL MOST CERTAINLY AFFECT PRECIP CHANCES DOWNSTREAM IN CENTRAL NC...LENDING A FAIR AMOUNT OF UNCERTAINTY TO THE PRECISE COVERAGE/AMOUNT OF CONVECTION TONIGHT. THE INCREASED CLOUD COVER WILL RESULT IN A SLIGHT DECREASE...ROUGHLY A DEGREE...FOR HIGH TEMPERATURES FOR THE WESTERN PART OF CENTRAL NORTH CAROLINA. HIGHS WERE RAISED ABOUT A DEGREE TOWARD INTERSTATE 95 WHERE THERE WILL BE MORE PERIODS OF THINNER CLOUDS AND MORE SUNLIGHT HITTING THE GROUND. A VERY MOIST AND BREEZY SOUTHERLY FLOW THROUGHOUT THE WARM SECTOR IN THE CAROLINAS WILL MAINTAIN TEMPS IN THE MID 60S OVERNIGHT. THOUGH QUITE CONDITIONAL/UNCERTAIN...IF DEEP CONVECTION DEVELOPS AND PROGRESSES INTO CENTRAL NC THIS EVENING AND TONIGHT...AN ISOLATED SEVERE STORM WOULD BE POSSIBLE GIVEN INCREASINGLY IMPRESSIVE LOW/DEEP-LAYER SHEAR. && .SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/... AS OF 330 AM MONDAY... TUE/TUE NIGHT: EXPECT CHANCES FOR CONVECTION NEAR 100% ON TUESDAY AS A POTENT UPPER LEVEL TROUGH AND ATTENDANT COLD FRONT PROGRESS THROUGH THE CAROLINAS IN THE PRESENCE OF A MOIST AND UNSTABLE AIRMASS VIA PERSISTENT SOUTHERLY LOW-LEVEL FLOW OFF THE ATLANTIC. AT THIS TIME...FROPA IS EXPECTED TO OCCUR BETWEEN 18-21Z IN THE NW PIEDMONT AND BY 00-03Z IN THE COASTAL PLAIN...WITH STRONG COLD ADVECTION THEREAFTER. EXPECT HIGHS RANGING FROM THE MID/UPPER 60S IN THE NW PIEDMONT WHERE CLOUD COVER/CONVECTION WILL PREVENT MUCH OF A RISE IN TEMPS PRIOR TO FROPA...TO THE MID/UPPER 70S POTENTIALLY IN THE COASTAL PLAIN WHERE FROPA WILL BE LATER. STRONG LOW/DEEP LAYER SHEAR...FAVORABLE DIURNAL TIMING...AND MARGINAL TO MODERATE DESTABILIZATION (500-1000 J/KG MLCAPE) CERTAINLY INDICATE A POTENTIAL FOR SEVERE THUNDERSTORMS...THOUGH THE PRECISE NATURE OF THE THREAT IS STILL DIFFICULT TO ASCERTAIN GIVEN A POTENTIAL FOR UPSTREAM CONVECTION /MCS ACTIVITY/ LATE TONIGHT AND TUE MORNING. DAMAGING WINDS AND ISOLD TORNADOES WILL BE THE PRIMARY THREAT(S)... THE LATTER OF WHICH COULD BE FURTHER ENHANCED BY BACKED SFC WINDS /LARGE CLOCKWISE CURVED HODOGRAPHS/ POSSIBLE ON THE EASTERN PERIPHERY OF ANY SFC WAVES WHICH COULD DEVELOP ALONG THE FRONT IN CENTRAL/EASTERN NC...PARTICULARLY ALONG AND EAST OF I-95 WHERE DIURNAL TIMING AND DESTABILIZATION WILL BE MOST FAVORABLE. STRONG COLD ADVECTION WILL RESULT IN A STARK CONTRAST IN TEMPERATURES IN COMPARISON TO THE PREVIOUS FEW DAYS...WITH LOWS RANGING FROM THE LOWER TO UPPER 30S...POTENTIALLY NEAR FREEZING ALONG/WEST OF HWY 1. A FREEZE WATCH MAY BE NEEDED FOR PORTIONS OF THE AREA TUE NIGHT/WED MORNING. SINCE LOWS WILL PRIMARILY DEPEND UPON COLD ADVECTION... SUFFICIENT UNCERTAINTY EXISTS TO PRECLUDE ANY FROST/FREEZE PRODUCT ISSUANCE AT THIS TIME. -VINCENT AS OF 245 AM MONDAY...RISING HEIGHTS ALOFT/DNVA AND ASSOCIATED STRONG SUBSIDENCE WILL RESULT IN FURTHER DEEP LAYER DRYING WED...FOLLOWED BY GENERALLY NEUTRAL VERTICAL MOTION BUT WITH STILL A RESIDUALLY DRY AND STRONGLY CAPPED REGIME OVER OUR REGION. SURFACE HIGH PRESSURE WILL CONSEQUENTLY BECOME UNSEASONABLY STRONG - INTO THE 1040-1045 MB RANGE AS IT BUILDS FROM THE OH VALLEY TO NEW ENGLAND. UNSEASONABLY COOL NORTHEASTERLY FLOW...WITH TEMPERATURES 10 TO 20 DEGREES BELOW AVERAGE...WILL RESULT OVER CENTRAL NC. INITIALLY CLEAR SKIES WED WILL BECOME PARTLY CLOUDY...TO PERHAPS MOSTLY SO IN THE COASTAL PLAIN...BY THU AFTERNOON...AS MOISTURE FLAT STRATOCUMULUS IS ADVECTED INLAND BENEATH THE CAP. PROJECTED LOW LEVEL THICKNESS VALUES IN THE 1300-1310 METER RANGE AT 12Z THU AND CLEAR SKIES WOULD SUPPORT SUB-FREEZING TEMPERATURES THU MORNING...BUT CONFIDENCE IS LOW REGARDING THE DEGREE OF CALM GIVEN A PROJECTED 4-6 MB RISE IN MSL PRESSURE WITH THE STRENGTHENING HIGH WED NIGHT. WILL ADJUST LOWS TO REFLECT MOSTLY LOWER TO MIDDLE 30S...COOLEST WEST...BUT THESE MAY NEED FURTHER DOWNWARD ADJUSTMENT (OR AT LEAST OPEN THE RANGE) TO INCLUDE SOME UPPER 20S (AROUND RECORD LOWS) IF IT INDEED APPEARS ANY PERIOD OF APPRECIABLE CALM WILL BE ATTAINED. SIMILARLY COOL IN THE MIDDLE 50S WED...WHICH MAY THREATEN THE RECORD LOW MAX OF 56 DEGREES AT KFAY FOR THE DATE. SEE CLIMATE SECTION BELOW. SLOW MODERATION TO AROUND 60 AND 40 DEGREES FOR HIGHS AND LOWS...RESPECTIVELY...THU AND THU NIGHT. -MWS && .LONG TERM /FRIDAY THROUGH SUNDAY/... AS OF 300 AM MONDAY... THOUGH MODEL SOLUTION SPREAD REMAINS ABOVE AVERAGE DURING THE LONG TERM...THE EMERGING SIGNAL FROM THE MAJORITY OF BOTH THE ENSEMBLE AND SOLUTIONS OS FOR A DOMINANT NORTHERN STREAM ACROSS THE NORTHERN THIRD OF THE US...ONE THAT WILL INCLUDE AT LEAST ONE PRIMARY SHORTWAVE TROUGH AND ACCOMPANYING SURFACE CYCLONE FORECAST TO CROSS THE UPPER MIDWEST AND LOWER GREAT LAKES FRI-SAT - A STORM TRACK THAT WOULD RESULT IN A MOSTLY DRY COLD FRONTAL PASSAGE SAT-SAT NIGHT AS DEPICTED BY AT LEAST THE LAST SEVERAL RUNS OF THE GFS. ON THE OTHER HAND...THE LAST COUPLE OF RUNS OF THE OPERATIONAL ECMWF...WHICH HAVE MINIMAL SUPPORT FROM THE EC ENSEMBLE MEAN...SUGGEST MORE IN THE WAY OF SOUTHERN STREAM TROUGHING/INTERACTION THAT WOULD RESULT IN SOME DEGREE OF COASTAL CYCLOGENESIS AND A WETTER PATTERN FOR AT LEAST THE EASTERN HALF OF NC DURING THE SAME TIME FRAME. IN EITHER SCENARIO...THE BEST CHANCES OF RAIN WOULD BE LATE FRI NIGHT-SAT EVENING...SO MENTIONABLE POP WILL BE CONFINED TO THAT TIME UNTIL A CLEARER PICTURE EMERGES. && .AVIATION /18Z MONDAY THROUGH SATURDAY/... AS OF 155 PM MONDAY... ASIDE FROM A THREAT OF BKN MVFR CIGS NEAR INT/GSO EARLY IN THE TAF PERIOD FROM 18Z-20Z TODAY... A PERIOD OF CONTINUED PREVAILING VFR CONDITIONS EXPECTED THIS AFTERNOON INTO EARLY EVENING (THROUGH AROUND 02Z OR 03Z)... WITH WINDS FROM THE SOUTH AT 8-15 KTS SPORADICALLY GUSTING TO 15-20 KTS... AND VFR CIGS. PATCHY SHOWERS MAY OCCUR PRIMARILY AT FAY... BUT ARE UNLIKELY TO LAST ANY MORE THAN 15 MIN AT ANY ONE TIME. AVIATION CONDITIONS ARE EXPECTED TO DETERIORATE THIS EVENING... AROUND 02Z OR 03Z... WITH CIGS DROPPING TO MVFR THEN FAIRLY QUICKLY TO IFR IN THE 04Z-06Z TIME FRAME... WITH CONTINUED STOUT WINDS FROM THE SOUTH AND SSW (FROM 180-210 DEGREES) STRENGTHENING TO AROUND 14-17 KTS GUSTING TO 20-25 KTS OVERNIGHT. EXPECT ON-AND-OFF MAINLY MVFR-VSBY-PRODUCING SHOWERS FROM THIS 04Z- 06Z TIME FRAME THROUGH AROUND 11Z-13Z. WINDS WILL REMAIN BLUSTERY FROM THE SSW THROUGH THE END OF THE TAF VALID PERIOD... POTENTIALLY INDUCING MECHANICAL TURBULENCE... BUT A LULL IN SHOWERS IS THEN EXPECTED FROM THIS 11Z-13Z WINDOW LASTING A FEW HOURS. CIGS MAY RISE A BIT TO MVFR DURING THIS RELATIVE LULL IN PRECIP. HOWEVER... AS A STRONG COLD FRONT APPROACHES FROM THE WEST... INT/GSO MAY SEE WIDESPREAD SHOWERS/STORMS MOVING IN TOWARD THE END OF THE TAF VALID PERIOD (AFTER 16Z). LOOKING BEYOND 18Z TUE: WIDESPREAD SHOWERS AND STORMS GENERATING IFR CONDITIONS WILL SPREAD WEST TO EAST ACROSS CENTRAL NC FROM 18Z THROUGH 06Z... AS A STRONG COLD FRONT CROSSES THE STATE. STRONG WINDS FROM THE SSW AND SW WILL SHIFT ABRUPTLY TO BE FROM THE NW TUE AFTERNOON. HIGH CONFIDENCE IN CLEARING SKIES AND VFR CONDITIONS POST- FRONT AFTER MIDNIGHT TUE NIGHT LASTING THROUGH THU EVENING. THERE IS A CHANCE OF SHALLOW LOW STRATUS LATE THU NIGHT/EARLY FRI MORNING... THEN A BETTER CHANCE OF THICKER LOW STRATUS FRI NIGHT THROUGH NOON SAT AHEAD OF THE NEXT STORM SYSTEM MOVING IN FROM THE SOUTH. -GIH && .CLIMATE... THE FOLLOWING ARE THE RECORD LOW TEMPERATURES FOR WED AND THU MORNING... AND THE RECORD LOW MAXIMUM TEMPERATURES FOR THU: WED 04/16 THU 04/17 LOW/YEAR LOW MAX/YEAR LOW/YEAR FAY: 28/1943 56/1950 31/1953 GSO: 25/1943 48/1929 29/1953 RDU: 28/1950 46/1890 29/1962 && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...HARTFIELD NEAR TERM...DJF/SR/VINCENT SHORT TERM...VINCENT LONG TERM...MWS AVIATION...HARTFIELD CLIMATE...MWS
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
123 PM EDT MON APR 14 2014 .SYNOPSIS... HIGH PRESSURE WILL MAINTAIN CONTROL OF THE WEATHER INTO TODAY. A COLD FRONT WILL MOVE ACROSS THE AREA TUESDAY...WITH INCREASING CHANCES FOR SHOWERS AND POSSIBLY THUNDERSTORMS LATE MONDAY INTO TUESDAY. HIGH PRESSURE WILL MOVE INTO THE AREA WEDNESDAY AND CONTROL AREA WEATHER INTO FRIDAY BEFORE CONDITIONS DETERIORATE IN ADVANCE OF A COLD FRONT THAT WILL MOVE THROUGH THE AREA SATURDAY NIGHT OR EARLY SUNDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1200 PM MONDAY...CURRENT RADAR IMAGERY SHOWS LIGHT SHOWERS MOVING ONSHORE AROUND THE WESTERN PERIPHERY OF HIGH PRESSURE WELL OFF THE ATLANTIC COAST. HAVE TRIMMED BACK POPS FOR OUR FAR WESTERN ZONES THIS AFTERNOON BASED ON RADAR TRENDS AND DRY MID-LEVEL AIR DEPICTED IN FCST SOUNDINGS. STILL EXPECT PCPN COVERAGE TO GRADUALLY INCREASE LATER TODAY INTO THIS EVENING AS DEPICTED BY HRRR AND OTHER HI RES MODELS. THE REST OF THE FORECAST STILL APPEARS ON TRACK ATTM. PREVIOUS DISCUSSION AS FOLLOWS... AS OF 1000 AM MONDAY...ANOTHER WARM DAY EXPECTED AS HIGH PRESSURE ONLY SLOWLY LOSES ITS GRIP ACROSS THE CAROLINAS...BUT MUCH MORE CLOUD COVER TODAY WILL KEEP TEMPS SEVERAL DEGREES COOLER THAN PREVIOUS DAYS. THIS CLOUD COVER IS DUE TO A COMBINATION OF INCREASED LOW LEVEL MOISTURE DUE TO ADVECTION OFF THE ATLANTIC...AND HIGH/MID CLOUDINESS AHEAD OF A STRONG COLD FRONT APPROACHING FROM THE WEST. THIS FRONT IS TRAILING FROM A CYCLONE MOVING UP THROUGH THE GREAT LAKES...AND ALTHOUGH ITS DIRECT IMPACTS WILL HOLD OFF UNTIL AFTER THIS PERIOD...CLOUDS AND SHOWERS WILL SLOWLY INCREASE IN COVERAGE TODAY. KLTX RADAR THIS MORNING HAS SHOWN A FEW SHOWERS TRYING TO MOVE ONSHORE FROM THE ATLANTIC ON S/SE WINDS...BUT MOST OF THESE ARE EVAPORATING AS THEY MOVE ACROSS THE COOLER SHELF WATERS...BEFORE COMING ONSHORE. EXPECT THIS TREND TO CONTINUE THROUGH THE AFTN...BUT COVERAGE AND INTENSITY OF THESE SHOWERS WILL LIKELY INCREASE AS MOISTURE AND INSTABILITY BECOME MORE SIGNIFICANT...AND AN ISOLATED RUMBLE OF THUNDER IS POSSIBLE. MOST OF THE HIGH RES MODELS...HRRR/ARW/WRF...SHOW A SIMILAR PATTERN OF SHOWERS MOVING ONSHORE BEFORE ROTATING NORTH AROUND THE HIGH PRESSURE...AND DUE TO THIS AGREEMENT HAVE SHOWN POP GRIDS WHICH MATCH THIS IDEA. AT THE SAME TIME...PRECIP WILL SLOWLY INCREASE FROM THE WEST AS THE COLD FRONT APPROACHES. MID-LEVEL DRYNESS WILL BE TOUGH TO OVERCOME...BUT BY TONIGHT FORECAST PROFILES SATURATE AND RAIN SHOWERS ARE EXPECTED TO BECOME NUMEROUS ACROSS THE AREA. TOTAL QPF WILL BE LIGHT THROUGH THE DAY...AS THE HEAVIEST RAIN HOLDS OFF UNTIL AFTER THE NEAR TERM PERIOD. TEMPS TODAY WILL RISE INTO THE MID/UPR 70S...HIGHEST INLAND. LOWS TONIGHT WILL BE TEMPERED BY CONTINUING SOUTHERLY WINDS AND INCREASING RAIN SHOWERS/CLOUD COVER...SO EXPECT A RATHER MINIMAL DIURNAL RANGE WITH MINS IN THE UPPER 60S AT THE COAST...MID 60S INLAND. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... AS OF 330 AM MONDAY...MID TO UPPER TROUGH EXTENDING DOWN FROM THE GREAT LAKES TO THE GULF COAST WILL PUSH A COLD FRONT EAST THROUGH THE CAROLINAS ON TUESDAY. INCREASINGLY WARM AND HUMID AIR MASS AHEAD OF THE FRONT WITH DEWPOINT TEMPS INTO THE MID 60S...WILL SET THE STAGE FOR INCREASED SHWR/TSTM ACTIVITY. LLJ UP TO 45 KTS COMBINED WITH MID TO UPPER LEVEL SUPPORT INCLUDING A STRONG JET WILL AID IN CONVECTIVE DEVELOPMENT. SPC CONTINUES TO HOLD US IN SLIGHT RISK WITH MAIN THREAT AS DAMAGING WIND AND POTENTIAL FOR A TORNADO IN SOME LINE SEGMENTS AND EMBEDDED SUPERCELLS TUES AFTN. THE CLOUDS MAY COME INTO PLAY AS A LIMITING FACTOR WORKING AGAINST THE CONTINUED WAA THROUGH TUES...BUT TEMPS WILL ALREADY BE WELL INTO THE 60S TO START THE DAY AND SHOULD MAKE IT WELL INTO THE 70S IN MOST PLACES. TEMPS SHOULD MODERATE WITH PLENTY OF MID TO HIGH CLOUDS OVER THE AREA AHEAD OF THE ACTUAL FRONT. BEST LIFT WILL COME AS FRONT MOVES THROUGH FROM WEST TO EAST THROUGH LATE AFTN INTO THE EVENING. A TOTAL CHANGE IN AIR MASS WILL COME AS HIGH PRESSURE BUILDS IN BEHIND FRONT THROUGH WED MORNING. PLENTY OF DRY AIR AND SUBSIDENCE WILL BE IN PLACE WITH CLEARING SKIES THROUGH DAYBREAK WED. PCP WATER VALUES UP AROUND 1.8 INCHES AHEAD OF FRONT LATE TUES WILL DROP TO AS LOW AS A QUARTER OF AN INCH BY WED MORNING. 850 TEMPS WILL PLUMMET FROM CLOSE TO 13C DOWN NEAR 4C BY WED MORNING. THIS STRONG CAA WILL BRING TEMPS DOWN ABOUT 20 DEGREES F FROM TUES TO WED. TEMPS BY WED MORNING WILL BE DOWN IN THE 30S OVER SOME PLACES INLAND. DEWPOINT TEMPS WILL DROP FROM THE MID 60S AHEAD OF THE FRONT DOWN TO MID 20S BY TUES AFTN. OVERALL EXPECT COOL NORTHERLY WINDS TO BE OFFSET BY PLENTY OF APRIL SUNSHINE TO PRODUCE TEMPS CLOSE TO 60. A PINCHED GRADIENT FLOW WILL KEEP N-NE FLOW REINFORCING THE COOL AIR THROUGH THURS NIGHT. TEMPS SHOULD DROP ONCE AGAIN INTO THE 30S MANY PLACES INLAND. && .LONG TERM /THURSDAY THROUGH SUNDAY/... AS OF 330 AM MONDAY...COOL AND DRY HIGH PRESSURE WILL BE IN PLACE AS WEDGE LIKE PATTERN DEVELOPS THURS INTO FRI WITH TROUGH OFF SHORE. THE GREATER ON SHORE COMPONENT TO THE FLOW WILL ALLOW MOISTURE TO INCREASE SLIGHTLY THROUGH THURS AND FURTHER INTO FRIDAY. PCP WATER VALUES REMAIN DOWN BELOW A HALF INCH THROUGH THURS BUT AS LOW PRESSURE DEVELOPS AND RISES UP FROM THE GULF COAST THROUGH FRI...THE SHALLOW COOL AND DRY AIR WILL BE OVERRUN WITH SOUTHERLY WINDS THROUGH THE LOW LEVELS. THIS WILL PROVIDE INCREASE ISENTROPIC LIFT THROUGH THE LATE THURS INTO FRI WITH LOW CLOUDS AND POSSIBILITY OF PCP. THE MOISTURE WILL REMAIN SHALLOW...BASICALLY BELOW 5K FT. AT THE SAME TIME A NORTHERN STREAM SYSTEM MOVES EAST DRAGGING A COLD FRONT TOWARD THE CAROLINAS. THIS SYSTEM MAY KEEP THE BEST MOISTURE AND LIFT OFF SHORE THROUGH FRI LEAVING A WEAKENING COLD FRONT MOVING THROUGH ON SATURDAY. KEPT POPS UP ON FRI ALTHOUGH NOT CONFIDENT THAT ENOUGH MOISTURE AND LIFT WILL REACH THIS FAR NORTH FROM GULF LOW BEFORE MOVING OFF SHORE. MAY END UP BEING MUCH MORE IN THE WAY OF CLOUDS THURS INTO FRI THAN PCP. TEMPS WILL REMAIN BELOW NORMAL IN CAA INITIALLY AND THEN CLOUDS WILL KEEP TEMPS LOWER. HIGH PRESSURE WILL BUILD IN BEHIND FRONT THROUGH SATURDAY INTO SUNDAY. ANOTHER COLD FRONT MAY MOVE EARLY NEXT WEEK WITH INCREASED CLOUDS AND CHC OF PCP BY SUN NIGHT. TEMPS WILL REACH BACK UP TOWARD NORMAL THROUGH THE WEEKEND. && .AVIATION /18Z MONDAY THROUGH SATURDAY/... AS OF 18Z...A STABLE LAYER AROUND 6500 FT HAS KEPT THE ATMOSPHERE A BIT CAPPED...BUT THAT STABLE LAYER SHOULD DISSIPATE THIS EVENING WITH MORE WIDESPREAD CONVECTION EXPECTED TO BREAK OUT AFTER MIDNIGHT. CEILINGS WILL LOWER WITH THE COMMENCEMENT OF PRECIP...POSSIBLY IFR CONDITIONS INLAND. WINDS WILL STAY ABOVE 7-8 KTS OVERNIGHT...IN FACT THEY WILL INCREASE TOWARD MORNING AS THE GRADIENT TIGHTENS AHEAD OF THE FRONT. TUESDAY...CONVECTION WILL BE IN AND OUT WITH DECENT COVERAGE. MODELS INDICATE WE WILL GET ENOUGH SOLAR INSOLATION AND WARM AIR ADVECTION TO SUPPORT POSSIBLE STRONG STORMS AFTER MIDDAY...STARTING FROM THE SOUTHWEST. CAPE COULD APPROACH 1000 J/KG WITH 55 KTS AT 2500 FEET. THE MARINE LAYER MAY SPARE THE COAST FROM STRONG STORMS IF THEY WAIT TO ARRIVE BY LATE AFTERNOON OR EVENING. EXTENDED OUTLOOK...BECOMING VFR TUESDAY NIGHT...CONTINUING THROUGH THURSDAY. POSSIBLE FOG/STRATUS FRIDAY AND SATURDAY...LOW CONFIDENCE. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 1000 AM MONDAY...HIGH PRESSURE CENTERED WELL OFFSHORE CONTINUES TO RIDGE BACK TOWARDS THE SOUTHEAST...BUT IS SLOWLY LOSING ITS GRIP OVER THE AREA. THIS IS DRIVING S/SE WINDS OF 10-15 KTS AT THE LOCAL BUOYS...WHICH WILL GRADUALLY VEER MORE TO THE SOUTH AND INCREASE TO 15-20 KTS TONIGHT. LOCAL SWAN GUIDANCE IS ABOUT 1 FT TOO HIGH WITH CURRENT SEAS...SO HAVE BLENDED DOWN WITH WNAWAVE TO MORE ACCURATELY REPRESENT ONGOING CONDITIONS...AND SHOW A SLOWER RISE IN WAVE HEIGHTS TONIGHT. STILL EXPECT SEAS TO BUILD TO 4-6 FT TONIGHT...AND A SMALL CRAFT ADVISORY REMAINS IN EFFECT...BEGINNING AT 2 AM TUESDAY. SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... AS OF 330 AM MONDAY...SMALL CRAFT CONDITIONS WILL PERSIST THROUGH MUCH OF THE PERIOD IN STRONG SOUTHERLY WINDS AHEAD OF A COLD FRONT AND NORTHERLY SURGE BEHIND COLD FRONT TUES NIGHT THROUGH WED NIGHT. MAY REACH GALE CRITERIA TUES NIGHT IN COLD SURGE AS HIGH PRESSURE BUILDS IN BEHIND COLD FRONT. WINDS WILL INCREASE UP TO 20 TO 25 KT TUESDAY BEFORE RAPIDLY SHIFTING TO THE NORTH AND INCREASING TO 25 TO 30 KT LATE TUESDAY NIGHT. SEAS WILL CONTINUE TO BUILD THROUGH TUES FROM 5 TO 7 FT UP TO 6 TO 8 FT TUES EVENING. AFTER THE COLD FRONT MOVES THROUGH TUESDAY EVENING A STRONG NORTHERLY FLOW UP TO 30 KTS WILL KEEP SEAS UP POSSIBLY TO 9 FT IN OUTER WATERS OVERNIGHT TUES INTO EARLY WED. GRADIENT WILL REMAIN TIGHT THROUGH WED AS NORTHERLY WINDS VEER SLIGHTLY TO THE NE AS HIGH PRESSURE RIDGES DOWN THROUGH THE CAROLINAS FROM THE NORTHEAST. LONG TERM /THURSDAY THROUGH FRIDAY/... AS OF 330 AM MONDAY...HIGH PRESSURE WILL CONTINUE TO RIDGE DOWN THROUGH THE CAROLINAS WHILE A WAVE OF LOW PRESSURE DEVELOPS OFF SHORE ALONG LINGERING COLD FRONT. STRONG NORTHERLY SURGE OF COLD AIR AND TIGHTENED GRADIENT FLOW WILL MAINTAIN N-NE WINDS CLOSER TO 20 KTS INITIALLY ACROSS THE WATERS THROUGH THURSDAY. WINDS WILL LIGHTEN AND VEER SLIGHTLY LATE THURS REMAINING CLOSER TO 15 KTS THROUGH FRI. SEAS SHOULD DROP DOWN BUT REMAIN 4 TO 6 FT THROUGH THURS NIGHT INTO FRI. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...SMALL CRAFT ADVISORY FROM 2 AM TUESDAY TO 6 PM EDT WEDNESDAY FOR AMZ250-252-254-256. && $$ SYNOPSIS...SHK NEAR TERM...JDW/BJR SHORT TERM...RGZ LONG TERM...RGZ AVIATION...43
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1214 PM EDT MON APR 14 2014 .SYNOPSIS... HIGH PRESSURE WILL MAINTAIN CONTROL OF THE WEATHER INTO TODAY. A COLD FRONT WILL MOVE ACROSS THE AREA TUESDAY...WITH INCREASING CHANCES FOR SHOWERS AND POSSIBLY THUNDERSTORMS LATE MONDAY INTO TUESDAY. HIGH PRESSURE WILL MOVE INTO THE AREA WEDNESDAY AND CONTROL AREA WEATHER INTO FRIDAY BEFORE CONDITIONS DETERIORATE IN ADVANCE OF A COLD FRONT THAT WILL MOVE THROUGH THE AREA SATURDAY NIGHT OR EARLY SUNDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1200 PM MONDAY...CURRENT RADAR IMAGERY SHOWS LIGHT SHOWERS MOVING ONSHORE AROUND THE WESTERN PERIPHERY OF HIGH PRESSURE WELL OFF THE ATLANTIC COAST. HAVE TRIMMED BACK POPS FOR OUR FAR WESTERN ZONES THIS AFTERNOON BASED ON RADAR TRENDS AND DRY MID-LEVEL AIR DEPICTED IN FCST SOUNDINGS. STILL EXPECT PCPN COVERAGE TO GRADUALLY INCREASE LATER TODAY INTO THIS EVENING AS DEPICTED BY HRRR AND OTHER HI RES MODELS. THE REST OF THE FORECAST STILL APPEARS ON TRACK ATTM. PREVIOUS DISCUSSION AS FOLLOWS... AS OF 1000 AM MONDAY...ANOTHER WARM DAY EXPECTED AS HIGH PRESSURE ONLY SLOWLY LOSES ITS GRIP ACROSS THE CAROLINAS...BUT MUCH MORE CLOUD COVER TODAY WILL KEEP TEMPS SEVERAL DEGREES COOLER THAN PREVIOUS DAYS. THIS CLOUD COVER IS DUE TO A COMBINATION OF INCREASED LOW LEVEL MOISTURE DUE TO ADVECTION OFF THE ATLANTIC...AND HIGH/MID CLOUDINESS AHEAD OF A STRONG COLD FRONT APPROACHING FROM THE WEST. THIS FRONT IS TRAILING FROM A CYCLONE MOVING UP THROUGH THE GREAT LAKES...AND ALTHOUGH ITS DIRECT IMPACTS WILL HOLD OFF UNTIL AFTER THIS PERIOD...CLOUDS AND SHOWERS WILL SLOWLY INCREASE IN COVERAGE TODAY. KLTX RADAR THIS MORNING HAS SHOWN A FEW SHOWERS TRYING TO MOVE ONSHORE FROM THE ATLANTIC ON S/SE WINDS...BUT MOST OF THESE ARE EVAPORATING AS THEY MOVE ACROSS THE COOLER SHELF WATERS...BEFORE COMING ONSHORE. EXPECT THIS TREND TO CONTINUE THROUGH THE AFTN...BUT COVERAGE AND INTENSITY OF THESE SHOWERS WILL LIKELY INCREASE AS MOISTURE AND INSTABILITY BECOME MORE SIGNIFICANT...AND AN ISOLATED RUMBLE OF THUNDER IS POSSIBLE. MOST OF THE HIGH RES MODELS...HRRR/ARW/WRF...SHOW A SIMILAR PATTERN OF SHOWERS MOVING ONSHORE BEFORE ROTATING NORTH AROUND THE HIGH PRESSURE...AND DUE TO THIS AGREEMENT HAVE SHOWN POP GRIDS WHICH MATCH THIS IDEA. AT THE SAME TIME...PRECIP WILL SLOWLY INCREASE FROM THE WEST AS THE COLD FRONT APPROACHES. MID-LEVEL DRYNESS WILL BE TOUGH TO OVERCOME...BUT BY TONIGHT FORECAST PROFILES SATURATE AND RAIN SHOWERS ARE EXPECTED TO BECOME NUMEROUS ACROSS THE AREA. TOTAL QPF WILL BE LIGHT THROUGH THE DAY...AS THE HEAVIEST RAIN HOLDS OFF UNTIL AFTER THE NEAR TERM PERIOD. TEMPS TODAY WILL RISE INTO THE MID/UPR 70S...HIGHEST INLAND. LOWS TONIGHT WILL BE TEMPERED BY CONTINUING SOUTHERLY WINDS AND INCREASING RAIN SHOWERS/CLOUD COVER...SO EXPECT A RATHER MINIMAL DIURNAL RANGE WITH MINS IN THE UPPER 60S AT THE COAST...MID 60S INLAND. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... AS OF 330 AM MONDAY...MID TO UPPER TROUGH EXTENDING DOWN FROM THE GREAT LAKES TO THE GULF COAST WILL PUSH A COLD FRONT EAST THROUGH THE CAROLINAS ON TUESDAY. INCREASINGLY WARM AND HUMID AIR MASS AHEAD OF THE FRONT WITH DEWPOINT TEMPS INTO THE MID 60S...WILL SET THE STAGE FOR INCREASED SHWR/TSTM ACTIVITY. LLJ UP TO 45 KTS COMBINED WITH MID TO UPPER LEVEL SUPPORT INCLUDING A STRONG JET WILL AID IN CONVECTIVE DEVELOPMENT. SPC CONTINUES TO HOLD US IN SLIGHT RISK WITH MAIN THREAT AS DAMAGING WIND AND POTENTIAL FOR A TORNADO IN SOME LINE SEGMENTS AND EMBEDDED SUPERCELLS TUES AFTN. THE CLOUDS MAY COME INTO PLAY AS A LIMITING FACTOR WORKING AGAINST THE CONTINUED WAA THROUGH TUES...BUT TEMPS WILL ALREADY BE WELL INTO THE 60S TO START THE DAY AND SHOULD MAKE IT WELL INTO THE 70S IN MOST PLACES. TEMPS SHOULD MODERATE WITH PLENTY OF MID TO HIGH CLOUDS OVER THE AREA AHEAD OF THE ACTUAL FRONT. BEST LIFT WILL COME AS FRONT MOVES THROUGH FROM WEST TO EAST THROUGH LATE AFTN INTO THE EVENING. A TOTAL CHANGE IN AIR MASS WILL COME AS HIGH PRESSURE BUILDS IN BEHIND FRONT THROUGH WED MORNING. PLENTY OF DRY AIR AND SUBSIDENCE WILL BE IN PLACE WITH CLEARING SKIES THROUGH DAYBREAK WED. PCP WATER VALUES UP AROUND 1.8 INCHES AHEAD OF FRONT LATE TUES WILL DROP TO AS LOW AS A QUARTER OF AN INCH BY WED MORNING. 850 TEMPS WILL PLUMMET FROM CLOSE TO 13C DOWN NEAR 4C BY WED MORNING. THIS STRONG CAA WILL BRING TEMPS DOWN ABOUT 20 DEGREES F FROM TUES TO WED. TEMPS BY WED MORNING WILL BE DOWN IN THE 30S OVER SOME PLACES INLAND. DEWPOINT TEMPS WILL DROP FROM THE MID 60S AHEAD OF THE FRONT DOWN TO MID 20S BY TUES AFTN. OVERALL EXPECT COOL NORTHERLY WINDS TO BE OFFSET BY PLENTY OF APRIL SUNSHINE TO PRODUCE TEMPS CLOSE TO 60. A PINCHED GRADIENT FLOW WILL KEEP N-NE FLOW REINFORCING THE COOL AIR THROUGH THURS NIGHT. TEMPS SHOULD DROP ONCE AGAIN INTO THE 30S MANY PLACES INLAND. && .LONG TERM /THURSDAY THROUGH SUNDAY/... AS OF 330 AM MONDAY...COOL AND DRY HIGH PRESSURE WILL BE IN PLACE AS WEDGE LIKE PATTERN DEVELOPS THURS INTO FRI WITH TROUGH OFF SHORE. THE GREATER ON SHORE COMPONENT TO THE FLOW WILL ALLOW MOISTURE TO INCREASE SLIGHTLY THROUGH THURS AND FURTHER INTO FRIDAY. PCP WATER VALUES REMAIN DOWN BELOW A HALF INCH THROUGH THURS BUT AS LOW PRESSURE DEVELOPS AND RISES UP FROM THE GULF COAST THROUGH FRI...THE SHALLOW COOL AND DRY AIR WILL BE OVERRUN WITH SOUTHERLY WINDS THROUGH THE LOW LEVELS. THIS WILL PROVIDE INCREASE ISENTROPIC LIFT THROUGH THE LATE THURS INTO FRI WITH LOW CLOUDS AND POSSIBILITY OF PCP. THE MOISTURE WILL REMAIN SHALLOW...BASICALLY BELOW 5K FT. AT THE SAME TIME A NORTHERN STREAM SYSTEM MOVES EAST DRAGGING A COLD FRONT TOWARD THE CAROLINAS. THIS SYSTEM MAY KEEP THE BEST MOISTURE AND LIFT OFF SHORE THROUGH FRI LEAVING A WEAKENING COLD FRONT MOVING THROUGH ON SATURDAY. KEPT POPS UP ON FRI ALTHOUGH NOT CONFIDENT THAT ENOUGH MOISTURE AND LIFT WILL REACH THIS FAR NORTH FROM GULF LOW BEFORE MOVING OFF SHORE. MAY END UP BEING MUCH MORE IN THE WAY OF CLOUDS THURS INTO FRI THAN PCP. TEMPS WILL REMAIN BELOW NORMAL IN CAA INITIALLY AND THEN CLOUDS WILL KEEP TEMPS LOWER. HIGH PRESSURE WILL BUILD IN BEHIND FRONT THROUGH SATURDAY INTO SUNDAY. ANOTHER COLD FRONT MAY MOVE EARLY NEXT WEEK WITH INCREASED CLOUDS AND CHC OF PCP BY SUN NIGHT. TEMPS WILL REACH BACK UP TOWARD NORMAL THROUGH THE WEEKEND. && .AVIATION /12Z MONDAY THROUGH FRIDAY/... AS OF 12Z...DENSE CIRRUS AND WINDS AROUND 5 KTS HAVE KEPT FOG AT BAY THIS MORNING. INCREASING CLOUDS TODAY AS THE COLD FRONT APPROACHES. AHEAD OF THE FRONT...LOOK FOR RISING DEWPOINTS AND AN INCREASING SOUTH WIND. SOME CONVERGENT BOUNDARIES AS WELL AS THE RESULTANT COULD KICK OFF LIGHT SHOWERS THIS AFTERNOON...FAIRLY SPARSE COVERAGE WITH A VCSH MENTION. TONIGHT...CEILINGS WILL LOWER AND PRECIPITATION WILL BECOME MORE WIDESPREAD TOWARD MORNING. THE PRESSURE GRADIENT WILL CONTINUE TO TIGHTEN...WITH GUSTY WINDS POSSIBLE AFTER MIDNIGHT. EXTENDED OUTLOOK...CHANCE OF SHOWERS AND MVFR CONDITIONS INTO TUESDAY WITH SHOWERS AND/OR THUNDERSTORMS ALONG A PASSING COLD FRONT. VFR WEDNESDAY AND THURSDAY. POSSIBLE FOG/STRATUS THURSDAY NIGHT INTO FRIDAY. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 1000 AM MONDAY...HIGH PRESSURE CENTERED WELL OFFSHORE CONTINUES TO RIDGE BACK TOWARDS THE SOUTHEAST...BUT IS SLOWLY LOSING ITS GRIP OVER THE AREA. THIS IS DRIVING S/SE WINDS OF 10-15 KTS AT THE LOCAL BUOYS...WHICH WILL GRADUALLY VEER MORE TO THE SOUTH AND INCREASE TO 15-20 KTS TONIGHT. LOCAL SWAN GUIDANCE IS ABOUT 1 FT TOO HIGH WITH CURRENT SEAS...SO HAVE BLENDED DOWN WITH WNAWAVE TO MORE ACCURATELY REPRESENT ONGOING CONDITIONS...AND SHOW A SLOWER RISE IN WAVE HEIGHTS TONIGHT. STILL EXPECT SEAS TO BUILD TO 4-6 FT TONIGHT...AND A SMALL CRAFT ADVISORY REMAINS IN EFFECT...BEGINNING AT 2 AM TUESDAY. SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... AS OF 330 AM MONDAY...SMALL CRAFT CONDITIONS WILL PERSIST THROUGH MUCH OF THE PERIOD IN STRONG SOUTHERLY WINDS AHEAD OF A COLD FRONT AND NORTHERLY SURGE BEHIND COLD FRONT TUES NIGHT THROUGH WED NIGHT. MAY REACH GALE CRITERIA TUES NIGHT IN COLD SURGE AS HIGH PRESSURE BUILDS IN BEHIND COLD FRONT. WINDS WILL INCREASE UP TO 20 TO 25 KT TUESDAY BEFORE RAPIDLY SHIFTING TO THE NORTH AND INCREASING TO 25 TO 30 KT LATE TUESDAY NIGHT. SEAS WILL CONTINUE TO BUILD THROUGH TUES FROM 5 TO 7 FT UP TO 6 TO 8 FT TUES EVENING. AFTER THE COLD FRONT MOVES THROUGH TUESDAY EVENING A STRONG NORTHERLY FLOW UP TO 30 KTS WILL KEEP SEAS UP POSSIBLY TO 9 FT IN OUTER WATERS OVERNIGHT TUES INTO EARLY WED. GRADIENT WILL REMAIN TIGHT THROUGH WED AS NORTHERLY WINDS VEER SLIGHTLY TO THE NE AS HIGH PRESSURE RIDGES DOWN THROUGH THE CAROLINAS FROM THE NORTHEAST. LONG TERM /THURSDAY THROUGH FRIDAY/... AS OF 330 AM MONDAY...HIGH PRESSURE WILL CONTINUE TO RIDGE DOWN THROUGH THE CAROLINAS WHILE A WAVE OF LOW PRESSURE DEVELOPS OFF SHORE ALONG LINGERING COLD FRONT. STRONG NORTHERLY SURGE OF COLD AIR AND TIGHTENED GRADIENT FLOW WILL MAINTAIN N-NE WINDS CLOSER TO 20 KTS INITIALLY ACROSS THE WATERS THROUGH THURSDAY. WINDS WILL LIGHTEN AND VEER SLIGHTLY LATE THURS REMAINING CLOSER TO 15 KTS THROUGH FRI. SEAS SHOULD DROP DOWN BUT REMAIN 4 TO 6 FT THROUGH THURS NIGHT INTO FRI. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...SMALL CRAFT ADVISORY FROM 2 AM TUESDAY TO 6 PM EDT WEDNESDAY FOR AMZ250-252-254-256. && $$ SYNOPSIS...SHK NEAR TERM...JDW/BJR SHORT TERM...RGZ LONG TERM...RGZ AVIATION...43
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1055 AM EDT MON APR 14 2014 .SYNOPSIS...SOUTHERLY FLOW WILL ADVECT AN INCREASINGLY MOIST AND UNSTABLE AIRMASS INTO THE REGION TODAY AND TONIGHT AS A POTENT UPPER LEVEL TROUGH AND ASSOCIATED COLD FRONT TRACK EAST INTO THE TENNESSEE VALLEY. THE COLD FRONT WILL PROGRESS EAST THROUGH THE CAROLINAS TUESDAY AFTERNOON AND EVENING. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1055 AM MONDAY... THE 12Z KGSO SOUNDING WAS CAPPED TO DEEP CONVECTION WITH A GOOD CAP BETWEEN 850MB AND 700MB...AND CONSIDERABLE MOISTURE ABOVE 500MB. THE LATEST SPC MESOANALYSIS SHOWED A RELATIVE MINIMUM OF PRECIPITABLE WATER VALUES OVER MUCH OF CENTRAL NORTH CAROLINA ALTHOUGH WITH A NARROW RIBBON OF INCREASING VALUES...JUST BELOW AN INCH...EXTENDING FROM SOUTH CAROLINA INTO THE SOUTHWEST PIEDMONT. HIGH PRESSURE EXTENDING OVER CENTRAL NORTH CAROLINA FROM THE EAST WAS PROVIDING A MOIST...SOUTHERLY FLOW OFF OF THE ATLANTIC INTO THE AREA...WITH SURFACE DEW POINTS IN THE MID 50S TO AROUND 60. TO OUR WEST...THE SURFACE LOW WILL INCREASE IN STRENGTH DUE TO THE OFFSET UPPER LEVEL TROUGH TO THE WEST. DIVERGENCE ALOFT IS DECREASING THE SURFACE PRESSURE AHEAD OF THE FRONT BRINGING IN CYCLONIC VORTICITY ADVECTION IN A SHORT WAVE AHEAD OF THE FRONT. SURFACE WINDS ARE SOUTHERLY AND HAVE INCREASED THE DEWPOINTS AS MOIST AND WARM AIR IS ADVECTED INTO THE AREA AHEAD OF THE COLD FRONT. WARM ADVECTION ALONG WITH CYCLONIC VORTICITY ADVECTION WILL BRING AN INCREASE IN LIFT AND CLOUD COVER OVER THE AREA AND AN INCREASED CHANCE FOR PRECIPITATION AND CONVECTION. A FEW SHOWERS ARE POPPING UP TO OUR WEST AND ARE EXPECTED TO INCREASE IN NUMBER AND EVENTUALLY PRODUCE CONVECTIVE STORMS AS THE COLD FRONT MOVES EASTWARD. THE 12Z UPPER-AIR ANALYSIS SHOWED SOME DIFFLUENCE TO OUR WEST AND THIS IS FORECAST TO CONTINUE THIS AFTERNOON INTO TONIGHT AS A SERIES OF MID-LEVEL WAVES MOVE THROUGH CENTRAL NORTH CAROLINA. THE LATEST RAP SHOWS THE MID-LEVEL CAP WEAKENING WITH TIME THROUGH EARLY AFTERNOON...AND SLIGHT 700MB COOLING ON THE 12Z UPPER-AIR ANALYSIS WOULD SUGGEST THIS...ALTHOUGH THE RAP ALSO FORECASTS A MODEST INCREASE IN THOSE MID-LEVEL TEMPERATURES LATE IN THE DAY. WITH THE MOISTURE IN PLACE...MODEST INSTABILITY WITH SURFACE-BASED CAPE AROUND 400J/KG AND MLCAPE IN THHIGHS TODAY WERE LOWERED ABOUT A DEGREE IN THE TRIAD DUE TO EXPECTED CLOUD COVER...AND RAISED ABOUT A DEGREE TOWARD INTERSTATE 95 DUE TO THINNER CLOUDS FOR A LONGER PERIOD OF TIME THERE. E LOWEST KM AROUND 200J/KG...AND SOME LIFT WITH THE MID-LEVEL SHORTWAVES...AS THE CAP ERODES ANTICIPATE ISOLATED TO SCATTERED SHOWERS DEVELOPING...WITH AN ISOLATED THUNDERSTORM POSSIBLE. AS THE MID-LEVEL TEMPERATURES WARM SLIGHTLY LATER...THIS COULD FOR A TIME INHIBIT MORE DEEP CONVECTION...AND THIS SCENARIO IS NOTED BY MORE THAN ONE WRF MODEL AS WELL AS IMPLIED BY RAP QPF. MOISTENING OF THE UPPER LEVELS WILL INCREASE CLOUD DEPTH AND ALLOW FOR LIFTING OVER A DEEPER LAYER. THIS WILL INCREASE THE CHANCE FOR SOME DEEP MOIST CONVECTION AND SHOWERS OVER THE AREA... HOWEVER...THE STRONGEST LIFTING WILL STAY TO THE WEST WITH THE COLD FRONT. CONVECTION SHOULD BECOME MORE NUMEROUS IN COVERAGE OVER CENTRAL NORTH CAROLINA THIS EVENING INTO TONIGHT DUE TO ONGOING MOISTENING...STRENGTHENING HEIGHT FALLS...AND PERIODIC DPVA IN SW FLOW ALOFT...ESPECIALLY IN WESTERN PORTIONS OF THE STATE. HOWEVER...SEVERAL LARGE MESOSCALE CONVECTIVE SYSTEMS ARE EXPECTED TO DEVELOP UPSTREAM IN THE DEEP SOUTH IN THIS PERIOD...ONE THIS AFTERNOON AND PERHAPS ANOTHER LATE TONIGHT...AND HOW THESE FEATURES EVOLVE/INTERACT WITH THE LARGER SCALE PATTERN WILL MOST CERTAINLY AFFECT PRECIP CHANCES DOWNSTREAM IN CENTRAL NC...LENDING A FAIR AMOUNT OF UNCERTAINTY TO THE PRECISE COVERAGE/AMOUNT OF CONVECTION TONIGHT. THE INCREASED CLOUD COVER WILL RESULT IN A SLIGHT DECREASE...ROUGHLY A DEGREE...FOR HIGH TEMPERATURES FOR THE WESTERN PART OF CENTRAL NORTH CAROLINA. HIGHS WERE RAISED ABOUT A DEGREE TOWARD INTERSTATE 95 WHERE THERE WILL BE MORE PERIODS OF THINNER CLOUDS AND MORE SUNLIGHT HITTING THE GROUND. A VERY MOIST AND BREEZY SOUTHERLY FLOW THROUGHOUT THE WARM SECTOR IN THE CAROLINAS WILL MAINTAIN TEMPS IN THE MID 60S OVERNIGHT. THOUGH QUITE CONDITIONAL/UNCERTAIN...IF DEEP CONVECTION DEVELOPS AND PROGRESSES INTO CENTRAL NC THIS EVENING AND TONIGHT...AN ISOLATED SEVERE STORM WOULD BE POSSIBLE GIVEN INCREASINGLY IMPRESSIVE LOW/DEEP-LAYER SHEAR. && .SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/... AS OF 330 AM MONDAY... TUE/TUE NIGHT: EXPECT CHANCES FOR CONVECTION NEAR 100% ON TUESDAY AS A POTENT UPPER LEVEL TROUGH AND ATTENDANT COLD FRONT PROGRESS THROUGH THE CAROLINAS IN THE PRESENCE OF A MOIST AND UNSTABLE AIRMASS VIA PERSISTENT SOUTHERLY LOW-LEVEL FLOW OFF THE ATLANTIC. AT THIS TIME...FROPA IS EXPECTED TO OCCUR BETWEEN 18-21Z IN THE NW PIEDMONT AND BY 00-03Z IN THE COASTAL PLAIN...WITH STRONG COLD ADVECTION THEREAFTER. EXPECT HIGHS RANGING FROM THE MID/UPPER 60S IN THE NW PIEDMONT WHERE CLOUD COVER/CONVECTION WILL PREVENT MUCH OF A RISE IN TEMPS PRIOR TO FROPA...TO THE MID/UPPER 70S POTENTIALLY IN THE COASTAL PLAIN WHERE FROPA WILL BE LATER. STRONG LOW/DEEP LAYER SHEAR...FAVORABLE DIURNAL TIMING...AND MARGINAL TO MODERATE DESTABILIZATION (500-1000 J/KG MLCAPE) CERTAINLY INDICATE A POTENTIAL FOR SEVERE THUNDERSTORMS...THOUGH THE PRECISE NATURE OF THE THREAT IS STILL DIFFICULT TO ASCERTAIN GIVEN A POTENTIAL FOR UPSTREAM CONVECTION /MCS ACTIVITY/ LATE TONIGHT AND TUE MORNING. DAMAGING WINDS AND ISOLD TORNADOES WILL BE THE PRIMARY THREAT(S)... THE LATTER OF WHICH COULD BE FURTHER ENHANCED BY BACKED SFC WINDS /LARGE CLOCKWISE CURVED HODOGRAPHS/ POSSIBLE ON THE EASTERN PERIPHERY OF ANY SFC WAVES WHICH COULD DEVELOP ALONG THE FRONT IN CENTRAL/EASTERN NC...PARTICULARLY ALONG AND EAST OF I-95 WHERE DIURNAL TIMING AND DESTABILIZATION WILL BE MOST FAVORABLE. STRONG COLD ADVECTION WILL RESULT IN A STARK CONTRAST IN TEMPERATURES IN COMPARISON TO THE PREVIOUS FEW DAYS...WITH LOWS RANGING FROM THE LOWER TO UPPER 30S...POTENTIALLY NEAR FREEZING ALONG/WEST OF HWY 1. A FREEZE WATCH MAY BE NEEDED FOR PORTIONS OF THE AREA TUE NIGHT/WED MORNING. SINCE LOWS WILL PRIMARILY DEPEND UPON COLD ADVECTION... SUFFICIENT UNCERTAINTY EXISTS TO PRECLUDE ANY FROST/FREEZE PRODUCT ISSUANCE AT THIS TIME. -VINCENT AS OF 245 AM MONDAY...RISING HEIGHTS ALOFT/DNVA AND ASSOCIATED STRONG SUBSIDENCE WILL RESULT IN FURTHER DEEP LAYER DRYING WED...FOLLOWED BY GENERALLY NEUTRAL VERTICAL MOTION BUT WITH STILL A RESIDUALLY DRY AND STRONGLY CAPPED REGIME OVER OUR REGION. SURFACE HIGH PRESSURE WILL CONSEQUENTLY BECOME UNSEASONABLY STRONG - INTO THE 1040-1045 MB RANGE AS IT BUILDS FROM THE OH VALLEY TO NEW ENGLAND. UNSEASONABLY COOL NORTHEASTERLY FLOW...WITH TEMPERATURES 10 TO 20 DEGREES BELOW AVERAGE...WILL RESULT OVER CENTRAL NC. INITIALLY CLEAR SKIES WED WILL BECOME PARTLY CLOUDY...TO PERHAPS MOSTLY SO IN THE COASTAL PLAIN...BY THU AFTERNOON...AS MOISTURE FLAT STRATOCUMULUS IS ADVECTED INLAND BENEATH THE CAP. PROJECTED LOW LEVEL THICKNESS VALUES IN THE 1300-1310 METER RANGE AT 12Z THU AND CLEAR SKIES WOULD SUPPORT SUB-FREEZING TEMPERATURES THU MORNING...BUT CONFIDENCE IS LOW REGARDING THE DEGREE OF CALM GIVEN A PROJECTED 4-6 MB RISE IN MSL PRESSURE WITH THE STRENGTHENING HIGH WED NIGHT. WILL ADJUST LOWS TO REFLECT MOSTLY LOWER TO MIDDLE 30S...COOLEST WEST...BUT THESE MAY NEED FURTHER DOWNWARD ADJUSTMENT (OR AT LEAST OPEN THE RANGE) TO INCLUDE SOME UPPER 20S (AROUND RECORD LOWS) IF IT INDEED APPEARS ANY PERIOD OF APPRECIABLE CALM WILL BE ATTAINED. SIMILARLY COOL IN THE MIDDLE 50S WED...WHICH MAY THREATEN THE RECORD LOW MAX OF 56 DEGREES AT KFAY FOR THE DATE. SEE CLIMATE SECTION BELOW. SLOW MODERATION TO AROUND 60 AND 40 DEGREES FOR HIGHS AND LOWS...RESPECTIVELY...THU AND THU NIGHT. -MWS && .LONG TERM /FRIDAY THROUGH SUNDAY/... AS OF 300 AM MONDAY... THOUGH MODEL SOLUTION SPREAD REMAINS ABOVE AVERAGE DURING THE LONG TERM...THE EMERGING SIGNAL FROM THE MAJORITY OF BOTH THE ENSEMBLE AND SOLUTIONS OS FOR A DOMINANT NORTHERN STREAM ACROSS THE NORTHERN THIRD OF THE US...ONE THAT WILL INCLUDE AT LEAST ONE PRIMARY SHORTWAVE TROUGH AND ACCOMPANYING SURFACE CYCLONE FORECAST TO CROSS THE UPPER MIDWEST AND LOWER GREAT LAKES FRI-SAT - A STORM TRACK THAT WOULD RESULT IN A MOSTLY DRY COLD FRONTAL PASSAGE SAT-SAT NIGHT AS DEPICTED BY AT LEAST THE LAST SEVERAL RUNS OF THE GFS. ON THE OTHER HAND...THE LAST COUPLE OF RUNS OF THE OPERATIONAL ECMWF...WHICH HAVE MINIMAL SUPPORT FROM THE EC ENSEMBLE MEAN...SUGGEST MORE IN THE WAY OF SOUTHERN STREAM TROUGHING/INTERACTION THAT WOULD RESULT IN SOME DEGREE OF COASTAL CYCLOGENESIS AND A WETTER PATTERN FOR AT LEAST THE EASTERN HALF OF NC DURING THE SAME TIME FRAME. IN EITHER SCENARIO...THE BEST CHANCES OF RAIN WOULD BE LATE FRI NIGHT-SAT EVENING...SO MENTIONABLE POP WILL BE CONFINED TO THAT TIME UNTIL A CLEARER PICTURE EMERGES. && .AVIATION /12Z MONDAY THROUGH SATURDAY/... AS OF 600 AM MONDAY... 24-HR TAF PERIOD: LOW-LEVEL MOISTENING /WARM ADVECTION/ IS EXPECTED TO RESULT IN THE RAPID DEVELOPMENT OF MVFR OR IFR CEILINGS BY 12-15Z ACROSS MUCH OF CENTRAL NC. SHALLOW CONVECTION (SHRA) WITH TOPS AROUND 10 KFT WILL BE POSSIBLE THROUGH EARLY AFTERNOON IN ASSOC/W AN ONSHORE FLOW IN THE LOWER-LEVELS...WITH ISOLD TO SCT SHOWERS AND THUNDERSTORMS POSSIBLE BY LATE THIS AFTERNOON AND EVENING IN ADVANCE OF A COLD FRONT PROGRESSING EAST INTO THE TN VALLEY. THERE SHOULD BE SOME MARGINAL IMPROVEMENT TO CEILINGS IN ASSOC/W DIURNAL HEATING... HOWEVER...DUE TO CONTINUED LOW-LEVEL MOISTENING CEILINGS MAY REMAIN IN THE MVFR CATEGORY...AT OR BELOW 2000 FT AGL. EXPECT CEILINGS TO DETERIORATE TO IFR/LIFR TONIGHT ALONG WITH AN INCREASING LIKELIHOOD OF SHOWER ACTIVITY IN ADVANCE OF THE APPROACHING COLD FRONT. SOUTHERLY WINDS AT 7-12 KT EARLY THIS MORNING WILL INCREASE TO 10-15 KT WITH GUSTS UP TO 22-25 KT DURING THE DAY...LIKELY REMAINING BREEZY AND GUSTING UP TO 20 KT OVERNIGHT AS THE MSLP GRADIENT TIGHTENS FROM THE WEST. LOOKING AHEAD: ADVERSE AVIATION CONDITIONS ASSOCIATED WITH WIDESPREAD SHOWERS AND THUNDERSTORMS ARE EXPECTED ON TUESDAY AS THE AFOREMENTIONED COLD FRONT PROGRESSES EAST ACROSS THE CAROLINAS. ISOLD SEVERE THUNDERSTORMS WILL BE POSSIBLE...ESPECIALLY AT THE RDU/FAY/RWI TERMINALS. SOUTHERLY OR SSW WINDS AT 15 KT WITH GUSTS UP TO 25 KT CAN BE EXPECTED IN ADVANCE OF THE FRONT THROUGH 18Z TUE...BECOMING NW/NNW AT 15 KT WITH GUSTS UP TO 25 KT BETWEEN ROUGHLY 18-21Z TUE AFTERNOON (INT/GSO) TO 00-03Z WED (FAY/RWI). IFR/LIFR CEILINGS MAY LINGER FOR A WHILE IN THE WAKE OF THE FRONTAL PASSAGE...EVENTUALLY CLEARING FROM WEST-EAST AND BECOMING VFR AFTER MIDNIGHT WED MORNING. VFR CONDITIONS WILL PREVAIL IN THE WAKE OF THE FRONT WED-FRI. -VINCENT && .CLIMATE... THE FOLLOWING ARE THE RECORD LOW TEMPERATURES FOR WED AND THU MORNING... AND THE RECORD LOW MAXIMUM TEMPERATURES FOR THU: WED 04/16 THU 04/17 LOW/YEAR LOW MAX/YEAR LOW/YEAR FAY: 28/1943 56/1950 31/1953 GSO: 25/1943 48/1929 29/1953 RDU: 28/1950 46/1890 29/1962 && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...VINCENT NEAR TERM...DJF/SR/VINCENT SHORT TERM...VINCENT LONG TERM...MWS AVIATION...VINCENT CLIMATE...MWS
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
718 PM CDT TUE APR 15 2014 .UPDATE... ISSUED AT 708 PM CDT TUE APR 15 2014 COORDINATED WITH WFO BIS AND IDEA WAS TO GREATLY BACK OFF ON POPS THIS EVENING AS VERY DRY AIRMASS WITH RETURN FLOW OUT OF DRY HIGH MOVING INTO NORTHWEST WISCONSIN WILL DRY UP MOST IF NOT ALL THE SNOW FROM REACHING THE GROUND IN MID LEVEL MOISTURE BAND FROM SOUTHEASTERN SASK INTO SOUTHEASTERN ND THRU 06Z. DEW PTS WILL RISE BUT STILL REMAIN IN THE TEENS IN THE RRV THIS EVE BEFORE REACHING 20S OVERNIGHT. MAIN SHORT WAVE ENERGY WILL MOVE FROM CENTRAL MONTANA INTO SOUTH DAKOTA WITH SURFACE LOW STRENGTHENING AS IT MOVES INTO CNTRL-ERN SD BY 12Z WED. MOST OF THE FORCING FOR LIFT IN THE MID LEVELS CONCENTRATES IN FAR NRN SD INTO CNTRL MN AT 12Z SKIRTING OUR FAR SOUTHEASTERN FCST AREA PER ADVISORY AREA. 12Z GEM WAS FARTHEST SOUTH WITH MAIN SNOW MORE SO WATERTOWN-WILMAR-ST CLOUD LINE VERSUS MORE ALONG A SISSETON-ELBOW LAKE-BRAINERD AXIS. RESULT OF DRIER AIR WILL GO DRY IN ERN ND THRU 06Z AND THEN KEEP HIGHER POPS AFTER 06Z IN SE ND INTO WCNTRL MN. 23Z RAP FOCUSES MOST SNOWFALL JUST A BIT SOUTH OF WHERE IT DID EARLIER MORE SO MILBANK SD INTO MORRIS MN TO LITTLE FALLS AGAIN SKIRTING FAR SOUTH WITH ANY SIG SNOWFALL AND JUST VERY LIGHT AMOUNTS UP TOWARD FARGO AND LITTLE TO NOTHING NORTH OF FARGO. TRIMMED POPS AND SNOW AMOUNTS TO REFLECT THIS THINKING. && .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT) ISSUED AT 245 PM CDT TUE APR 15 2014 FORECAST CHALLENGE CONCERNS MAINLY SNOW EVENT LATER TONIGHT INTO WEDNESDAY. MODELS SEEM TO BE COMING INTO BETTER ALIGNMENT WITH MORE SIGNIFICANT SNOW BAND FOR WEDNESDAY. GFS/NAM/GEM HAVE TRENDED SLIGHTLY SOUTHWARD WITH MAIN SNOW BAND. ECMWF REMAINS CONSISTENT WITH LESS QPF THROUGH THE EVENT. FOR TONIGHT MODELS IN GOOD AGREEMENT WITH BAND OF LIGHT SNOW SPREADING NW-SE ACROSS THE FA. DOES NOT APPEAR TO BE A GREAT DEAL OF UPPER FORCING AS MAIN WAVE JUST CROSSING THE NORTHERN ROCKIES. TOWARDS MORNING AS WAVE APPROACHES H7 LOW BECOMES BETTER ORGANIZED OVER E CENTRAL SD WITH FAVORED FRONTOGENETIC FORCING/Q-VECTOR CONVERGENCE ALONG AND NORTH OF LOW. SO EXPECT NW-SE ORIENTED SNOW BAND TO BECOME MORE E-W FROM EASTERN SD-WEST CENTRAL MN WITH COMMON ND BORDER AREA ON NORTHERN FRINGE. OVERALL STILL LOOKING AT GENERAL 1-3 INCHES OVERNIGHT. MIXING AND CLOUDS WILL LIMIT TEMPERATURE DROP OVERNIGHT. ON WEDNESDAY FRONTOGENETIC FORCING/ Q VECTOR CONVERGENCE SHIFTS DUE EAST FROM E SD INTO S MN. THIS WILL PUT FAR SE FA ON NORTHERN AND WESTERN FRINGE OF HEAVIER SNOW BAND. FOR THIS HAVE ISSUED WINTER WX ADVISORY FOR 3-5 INCHES OF SNOW. SNOW RATIOS AND IF WE CAN GET TO OR ABOVE MELTING WILL HAVE A BEARING ON SNOW AMOUNTS. SNOW SHOULD BEGIN TO PULL EAST MID AFTERNOON. ANY LINGERING SNOW WILL DIMINISH EARLY EVENING. NOT MUCH COLDER AIR WRAPPING AROUND SYSTEM AND DEPENDENT ON CLOUDS WILL CONTINUE TO SEE TEMPERATURES BLO AVERAGE ESPECIALLY WITH NEW SNOW FALL. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 245 PM CDT TUE APR 15 2014 HIGH PRESSURE TO BUILD IN THURSDAY AND WITH SLIGHTLY WARMER COLUMN AND MID APRIL SOLAR TEMPERATURES SHOULD RECOVER IN SPITE OF FRESH SNOW. REMAINDER OF THE WORK WEEK LOOKS QUIET WITH MODERATING TEMPERATURES. FRIDAY NIGHT TO TUESDAY...HIGH CONFIDENCE IN A WARM UP ACROSS THE NORTHERN PLAINS FOR EASTER WEEKEND INTO NEXT WEEK. INCREASING THICKNESSES AS 500MB FLOW BECOMES MORE ZONAL AND 850MB WAA BEGINS SATURDAY IN WHICH NWP INDICATES A POTENTIAL FOR A BAND OF WAA PCPN FROM WEST TO EAST TO CROSS THE AREA. ZONAL FLOW CONTINUES SUNDAY INTO MONDAY BEFORE MORE RIDGING MONDAY INTO TUESDAY WHERE GUIDANCE IS SHOWING 60S FOR HIGHS ON MONDAY AND TUESDAY NEXT WEEK. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING) ISSUED AT 708 PM CDT TUE APR 15 2014 WINDS WILL BE MAIN HAZARD IN THE AREA NEXT 24 HOURS AS SOUTHEAST TO EAST WINDS INCREASE AS LOW DEVELOPS IN SOUTH DAKOTA TONIGHT AND MOVES INTO MINNESOTA WEDNESDAY. TIGHT PRESSURE GRADIENT BETWEEN THE LOW AND HIGH IN MANITOBA-NW ONTARIO TO HAVE A STRONG EAST TO NORTHEAST SURFACE WIND OVER THE AREA WEDNESDAY WITH SUSTAINED 15 TO 22 KTS AND GUSTS OVER 30 KTS IN PLACES. PER MOISTURE CROSS SECTIONS SHOULD HAVE MOSTLY VFR CIGS THRU WED IN DVL-GFK-TVF-BJI AREAS WITH LIGHT SNOW MVFR VSBYS AND CIGS IN FARGO LATE TONIGHT INTO WED MIDDAY. SOME AREAS OF MVFR CIGS PSBL DVL-GFK-TVF-BJI AS WELL BUT FEEL IT SHOULD STAY MORE ON THE LOW END VFR RANGE. DID HAVE SOME LIGHT SNOW INTO BJI 15Z WED BUT THAT IS MUCH MORE UNCERTAIN AS MORE DATA COMES IN. && HYDRO...THE COLD NIGHTS AND COOL DAYTIME HIGHS ARE PUTTING A DAMPER ON ANY ADDITIONAL RUNOFF. WAS ABLE TO ISSUE LAST FORECASTS FOR SABIN DILWORTH AND GRAFTON. THE REMAINING POINTS IN HYDROLOGIC STATEMENTS OR FLOOD STATEMENTS ARE ALL AT OR NORTH OF GRAND FORKS. ONLY SITES STILL RISING ARE DRAYTON AND PEMBINA ON THE RED RIVER. STILL ANTICIPATE THE COOLER WEATHER LASTING INTO THURSDAY WITH SOME MODERATION COMING BY LATE WEEK INTO THE WEEKEND. THE NEXT STORM SYSTEM FOR TONIGHT INTO WEDNESDAY NIGHT LOOKS TO MAINLY AFFECT PORTIONS OF WEST CENTRAL MINNESOTA WITH LITTLE OR NO PRECIPITATION OVER THE NORTHERN RED RIVER VALLEY. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...WINTER WEATHER ADVISORY FROM 4 AM TO 6 PM CDT WEDNESDAY FOR MNZ030>032-040. && $$ UPDATE...RIDDLE SHORT TERM...VOELKER LONG TERM...JK/VOELKER AVIATION...RIDDLE HYDROLOGY...VG
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
913 PM EDT TUE APR 15 2014 .SYNOPSIS... HIGH PRESSURE WILL BUILD OVER THE FORECAST AREA TONIGHT. THIS SYSTEM WILL REMAIN OVER THE REGION THROUGH THURSDAY. A COLD FRONT WILL MOVE ACROSS THE AREA FRIDAY EVENING. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... THE DIURNAL SHSN HAVE MOSTLY DISSIPATED LEAVING MOSTLY JUST LAKE EFFECT SHSN. STILL NOT GETTING AN HRRR MODEL RUNS BUT LATEST RUC STILL HAS LAST OF MEASURABLE SHSN ENDING BY 05Z. BASED ON THE RUC AND LATEST RADAR AND SAT PIX...LOOKS LIKE ONGOING FORECAST REMAINS IN LINE SO NO CHANGES OF SIGNIFICANCE FOR LATE EVENING UPDATE. FROM HERE ON OUT ANY ADDITIONAL ACCUMULATION SHOULD JUST A HALF AN INCH OR LESS HERE AND THERE WHERE SNOW SHOWERS PERSIST. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY NIGHT/... HIGH PRESSURE WILL REMAIN IN CONTROL OF THE WEATHER PATTERN FOR THE MID TO LATER PART OF THE WEEK. A RETURN FLOW ON THE BACK SIDE OF THE HIGH WILL ALLOW TEMPERATURES TO START A REBOUND ON WEDNESDAY AND CLIMB BACK TO NEAR NORMALS ON THURSDAY. THE GFS AND NAM SHOW AN APPROACHING COLD FRONT ON FRIDAY. THE NAM IS A LITTLE QUICKER AND A LITTLE MORE AGGRESSIVE WITH THE MOISTURE WITH THE SYSTEM THAN THE GFS. I WILL WORK SCATTERED PRECIPITATION ACROSS THE AREA WITH MORNING SHOWERS IN NW OHIO AND THEN AFTERNOON SHOWERS IN NE OH AND NW PA. 850MB TEMPERATURES DROP BELOW -2C FRIDAY NIGHT. WE MAY HAVE TO WATCH PRECIPITATION TYPE AS WELL. RIGHT NOW I WILL NOT INCLUDE ANY MIXED PRECIPITATION FRIDAY NIGHT. && .LONG TERM /SATURDAY THROUGH TUESDAY/... THE EXTENDED FORECAST BEGINS WITH A SHARP LONGWAVE RIDGE MOVING INTO THE GREAT LAKES REGION. ALL OF SATURDAY AND MOST OF SUNDAY WILL BE DRY. A FAST MOVING SHORTWAVE TROUGH ON THE HEELS OF SATURDAY`S RIDGE WILL ELEVATE POPS ACROSS THE TOLEDO METRO AREA AS EARLY AS SUNDAY AFTERNOON...BUT CHANCE FOR MEASURABLE PRECIP WILL BE LOW AS THE TROUGH FLATTENS OUT. MONDAY AND THE FIRST PART OF TUESDAY LOOK LIKE THE BETTER DAY FOR RAIN AS A SLOW MOVING DISTURBANCE DEVELOPS OVER THE DEEP SOUTH AND DRAWS UP GULF MOISTURE TOWARDS THE OHIO VALLEY. THE GOOD NEWS IS THE LAST OF THE COLD WEATHER APPEARS TO BE BEHIND US WITH HIGH TEMPERATURES FORECAST TO BE NEARLY NORMAL. && .AVIATION /00Z WEDNESDAY THROUGH SUNDAY/... HIGH PRESSURE WILL MOVE ACROSS THE AREA LATER TONIGHT AND WED MORNING. THE REMAINING CLOUDS AND SNOW SHOWERS WILL CLEAR FROM WEST TO EAST AND ALL FORECAST SITES WILL BECOME VFR TONIGHT. VFR WEDNESDAY. WINDS WILL BECOME SOUTHEAST EXCEPT FOR A LAKE BREEZE ALONG THE LAKE ERIE SHORE IN THE AFTERNOON. .OUTLOOK...NON VFR MAY DEVELOP FRIDAY AND PERSIST INTO SATURDAY. && .MARINE... THE SMALL CRAFT ADVISORY IS STILL ON TRACK TO EXPIRE LATER TONIGHT AS THE WIND ACROSS THE LAKE DIMINISHES IN RESPONSE TO A HIGH PRESSURE CENTER THAT WILL MOVE ACROSS NORTHERN OHIO LATER TONIGHT. IN THE WAKE OF THE HIGH THE WIND WILL SHIFT FROM THE SOUTH...THEN GENERALLY THE SOUTHWEST AS THE NEXT SYSTEM EVOLVES OVER THE UPPER MIDWEST FOR PASSAGE OVER LAKE ERIE EARLY SATURDAY. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 3 AM EDT WEDNESDAY FOR LEZ142>149. && $$ SYNOPSIS...GARNET NEAR TERM...GARNET/ADAMS SHORT TERM...GARNET LONG TERM...MAYERS AVIATION...KOSARIK MARINE...MAYERS
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
637 AM EDT MON APR 14 2014 .SYNOPSIS... STRONG COLD FRONT MONDAY NIGHT. HIGH PRESSURE REST OF THE WORK WEEK. && .NEAR TERM /THROUGH TONIGHT/... UPDATE... BUMPED UP THE TIMING OF THE POPS IN A FEW ISOLATE WARM ADVECTION SHOWERS THIS MORNING. OTHERWISE...NO MAJOR CHANGES TO THE FORECAST. PREVIOUS DISCUSSION... 00Z RUN OF THE NAM CAME OUT WITH A DISTINGUISHED LINE OF CONVECTION WELL AHEAD OF THE COLD FRONT AND THE MID AND UPPER LEVEL TROUGH AXES. GFS CAME IN SUPPORTING THE SAME FEATURE...WITH THE HRRR IN LINE AS WELL AS THE LINE COMES INTO THE SCOPE OF THAT MODEL/S FORECAST RANGE. THIS IS THE ONLY MAJOR CHANGE TO THE FORECAST. SPC KEEPS THE SLIGHT RISK OF SEVERE WEATHER WELL TO THE SOUTH THANKS TO LOW DEWPOINTS CONTRIBUTING TO LOW SURFACE BASED CAPE. A DEVELOPING WAVE ALONG THE FRONT WILL KEEP THE PRECIPITATION CHANCES ENHANCED THROUGH THE MONDAY NIGHT PERIOD...WITH THE HINTS OF CLEARING COMING IN THE NORTHWEST ZONES AT 12Z TUESDAY IN THE FORM OF POPS DROPPING TO CHANCE. AFTER A VERY WARM MORNING...TEMPERATURES WILL PUSH THE 80F MARK AGAIN TODAY...COOLER WITHOUT MUCH SUN TO SPEAK OF...BUT STILL WELL ABOVE NORMAL IN THE WARM SECTOR. && .SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/... GOOD MODEL AGREEMENT ON TIMING OF THE STRONG COLD FRONT EXITING THE MOUNTAINS EARLY TUESDAY MORNING...FOLLOWED BY MOSTLY FALLING TEMPERATURES DURING THE DAY. POST FRONTAL PRECIPITATION WILL END FROM WEST TO EAST DURING THE DAY...WITH MODELS ALSO AGREEING ON THE EXIT TIMING OF THE DEEPER MOISTURE AND PRECIP WITH THE SYSTEM. BY DAYS END ONLY A SLIGHT CHANCE WILL LINGER IN THE NORTHERN MOUNTAINS...ENDING BY MIDNIGHT. THE BIG CHALLENGE IS THE NON DIURNAL TEMPERATURE CURVE DURING TUESDAY...IN THE VERY STRONG COLD ADVECTION AND UNUSUALLY COLD AIRMASS FOR THIS TIME OF YEAR...AND THUS THE PROSPECTS OF RAIN TO SNOW. GIVEN THE COLD MODEL CONSENSUS ALOFT WHICH WOULD SUPPORT A CHANGEOVER TO SNOW FROM WEST TO EAST TOWARD THE END OF THE PRECIPITATION...THE ISSUE WILL BE THE BOUNDARY LAYER TEMPERATURES. MODELS DO SHOW STRONG TEMPERATURE FALLS IN THE MORNING AND TENDING TO LEVEL OUT FOR A TIME IN THE LOW LANDS IN THE AFTERNOON...BEFORE FALLING AGAIN TUESDAY NIGHT. THIS IS REASONABLE FOR THIS TIME OF YEAR...AND ESPECIALLY IN THE WEST AND CENTRAL AS PRECIPITATION ENDS EARLIER IN THE DAY. WILL GO WITH THE NAM MOS GUIDANCE...MAINLY BECAUSE IT BEST SHOWS A BREAK IN THE TEMPERATURE FALLS DURING THE AFTERNOON...ESPECIALLY WEST AND CENTRAL. THUS...BELIEVE ANY MIX/CHANGEOVER TO SNOW IN THE LOW LANDS WILL BE BRIEF BEFORE THE PRECIPITATION ENDS WITH NO ACCUMULATIONS...AS SURFACE TEMPERATURES WILL STILL BE ABOVE FREEZING AND THE GROUND QUITE WARM. IN THE CENTRAL AND NORTHERN MOUNTAINS...THERE WILL BE A CHANGEOVER TO SNOW DURING THE AFTERNOON...BUT ACCUMULATIONS WILL LIKELY BE AN INCH OR LESS AND MOSTLY CONFINED TO THE HIGHER ELEVATIONS. LOOK FOR TEMPERATURES TO START OUT TUESDAY MORNING IN THE 50S EAST AND NEAR 40 FAR WEST...REACHING BY EVENING THE LOW TO MID 30S MOST OF THE LOW LANDS AND BELOW FREEZING ABOVE 2000 FEET. WHILE SNOW SHOWERS TAPER OFF EARLY TUESDAY NIGHT IN THE MOUNTAINS... CLEARING FOLLOWS MORE SLOWLY WITH THE COLD ADVECTION AND UPSLOPE FLOW IN THE MOUNTAINS. STILL...IT SHOULD BECOME MOSTLY CLEAR EARLY ENOUGH AS DRY HIGH PRESSURE BUILDS IN RAPIDLY FROM THE WEST...AND ALLOW TEMPERATURES TO FALL WELL BELOW FREEZING IN ALL LOCATIONS. HOWEVER...BELIEVE THE MODELS MAY BE A BIT ON THE LOW SIDE AS THEY FORECAST A RUN FOR RECORD LOWS TUESDAY NIGHT. FOR NOW...WILL KEEP OUR MINS A COUPLE OF DEGREES ABOVE THE MOS...BUT STILL WELL BELOW FREEZING. THEREAFTER...HIGH PRESSURE SLIDES ACROSS WITH ABUNDANT SUNSHINE WEDNESDAY AND THURSDAY...ALONG WITH A WARMING TREND. WITH DRY AIR AND LIGHT WINDS WEDNESDAY NIGHT...TEMPERATURES COULD FALL BELOW FREEZING AGAIN. && .LONG TERM /FRIDAY THROUGH SUNDAY/... SW FLOW DOMINATES THROUGH FRIDAY BEFORE S/W TROF TRIES TO CREATE FOR AN UNSETTLED SATURDAY. DUE TO CONTINUED DIFFERENCES REGARDING AMPLITUDE AND STRENGTH OF SURFACE FEATURES...HAVE STAYED CLOSE TO WPC PREFERRED SOLUTION WITH THREAT FOR SHRA FRIDAY NIGHT AND SATURDAY. FOR TEMPS...A WARMING TREND WILL BE NOTED TO ROUND OUT THE WORK WEEK...BEFORE COOLER BUT MORE SEASONAL AIR ARRIVES FOR THE WEEKEND. && .AVIATION /12Z MONDAY THROUGH FRIDAY/... SHOWERS WILL MOVE IN OVER THE NEXT FEW HOURS...AND INTO THE WESTERN TERMINALS AFTER 15Z. TSRA POSSIBLE TODAY...BUT CANNOT PUT IN PREVAILING CONDITIONS AND HAVE OPTED AGAIN FOR THE VCTS/CB CODING IN THE TAFS. THIS IS IN PART DUE TO AN ATMOSPHERE THAT IS NOT THE MOST CONDUCIVE BECAUSE OF MODEST INSTABILITY. STILL...ISOLATED TO SCATTERED TSRA WILL EXIST...AND A TEMPO OR TWO IN AN AMENDMENT IS LIKELY. MVFR CEILINGS ARE THE BEST BET IN THE WARM SECTOR AHEAD OF THE COLD FRONT WITH SHRA/TSRA. SAME WITH THE VISIBILITIES IN PRECIPITATION. BRIEF IFR IS POSSIBLE. WINDS AHEAD OF THE FRONT WILL GUST TO 20KTS WITH THE OCCASIONAL 25KT GUST OUT OF THE SOUTH. A SHIFT TO THE WEST NORTHWEST CAN BE EXPECTED BEHIND THE FRONT...WHICH WILL PASS TONIGHT. FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z TUESDAY... FORECAST CONFIDENCE: MEDIUM. ALTERNATE SCENARIOS: CONVECTION TIMING AND BRIEF FLIGHT CATEGORY BOUNCES COULD LEAD TO TEMPOS AND AMENDMENTS. MAY NEED PREVAILING TSRA. EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY OF WFO FORECAST TO AVAILABLE MODEL INFORMATION: H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS. L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. UTC 1HRLY 11 12 13 14 15 16 17 18 19 20 21 22 EDT 1HRLY 07 08 09 10 11 12 13 14 15 16 17 18 CRW CONSISTENCY H H H H H H H H H H H H HTS CONSISTENCY H H H H H H H H H H H H BKW CONSISTENCY H H H H H H H H H H H H EKN CONSISTENCY H H H H H H H H H H H H PKB CONSISTENCY H H H H H H H H H H H H CKB CONSISTENCY H H H H H H H H H H H H AFTER 12Z TUESDAY... IFR CONDITIONS EXPECTED LATE MONDAY NIGHT UNDER MODERATE RAIN SHOWERS. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...NONE. OH...NONE. KY...NONE. VA...NONE. && $$ SYNOPSIS...JMV/26 NEAR TERM...26 SHORT TERM...JMV LONG TERM...30 AVIATION...26
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
336 AM EDT MON APR 14 2014 .SYNOPSIS... STRONG COLD FRONT MONDAY NIGHT. HIGH PRESSURE REST OF THE WORK WEEK. && .NEAR TERM /THROUGH TONIGHT/... 00Z RUN OF THE NAM CAME OUT WITH A DISTINGUISHED LINE OF CONVECTION WELL AHEAD OF THE COLD FRONT AND THE MID AND UPPER LEVEL TROUGH AXES. GFS CAME IN SUPPORTING THE SAME FEATURE...WITH THE HRRR IN LINE AS WELL AS THE LINE COMES INTO THE SCOPE OF THAT MODEL/S FORECAST RANGE. THIS IS THE ONLY MAJOR CHANGE TO THE FORECAST. SPC KEEPS THE SLIGHT RISK OF SEVERE WEATHER WELL TO THE SOUTH THANKS TO LOW DEWPOINTS CONTRIBUTING TO LOW SURFACE BASED CAPE. A DEVELOPING WAVE ALONG THE FRONT WILL KEEP THE PRECIPITATION CHANCES ENHANCED THROUGH THE MONDAY NIGHT PERIOD...WITH THE HINTS OF CLEARING COMING IN THE NORTHWEST ZONES AT 12Z TUESDAY IN THE FORM OF POPS DROPPING TO CHANCE. AFTER A VERY WARM MORNING...TEMPERATURES WILL PUSH THE 80F MARK AGAIN TODAY...COOLER WITHOUT MUCH SUN TO SPEAK OF...BUT STILL WELL ABOVE NORMAL IN THE WARM SECTOR. && .SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/... GOOD MODEL AGREEMENT ON TIMING OF THE STRONG COLD FRONT EXITING THE MOUNTAINS EARLY TUESDAY MORNING...FOLLOWED BY MOSTLY FALLING TEMPERATURES DURING THE DAY. POST FRONTAL PRECIPITATION WILL END FROM WEST TO EAST DURING THE DAY...WITH MODELS ALSO AGREEING ON THE EXIT TIMING OF THE DEEPER MOISTURE AND PRECIP WITH THE SYSTEM. BY DAYS END ONLY A SLIGHT CHANCE WILL LINGER IN THE NORTHERN MOUNTAINS...ENDING BY MIDNIGHT. THE BIG CHALLENGE IS THE NON DIURNAL TEMPERATURE CURVE DURING TUESDAY...IN THE VERY STRONG COLD ADVECTION AND UNUSUALLY COLD AIRMASS FOR THIS TIME OF YEAR...AND THUS THE PROSPECTS OF RAIN TO SNOW. GIVEN THE COLD MODEL CONSENSUS ALOFT WHICH WOULD SUPPORT A CHANGEOVER TO SNOW FROM WEST TO EAST TOWARD THE END OF THE PRECIPITATION...THE ISSUE WILL BE THE BOUNDARY LAYER TEMPERATURES. MODELS DO SHOW STRONG TEMPERATURE FALLS IN THE MORNING AND TENDING TO LEVEL OUT FOR A TIME IN THE LOW LANDS IN THE AFTERNOON...BEFORE FALLING AGAIN TUESDAY NIGHT. THIS IS REASONABLE FOR THIS TIME OF YEAR...AND ESPECIALLY IN THE WEST AND CENTRAL AS PRECIPITATION ENDS EARLIER IN THE DAY. WILL GO WITH THE NAM MOS GUIDANCE...MAINLY BECAUSE IT BEST SHOWS A BREAK IN THE TEMPERATURE FALLS DURING THE AFTERNOON...ESPECIALLY WEST AND CENTRAL. THUS...BELIEVE ANY MIX/CHANGEOVER TO SNOW IN THE LOW LANDS WILL BE BRIEF BEFORE THE PRECIPITATION ENDS WITH NO ACCUMULATIONS...AS SURFACE TEMPERATURES WILL STILL BE ABOVE FREEZING AND THE GROUND QUITE WARM. IN THE CENTRAL AND NORTHERN MOUNTAINS...THERE WILL BE A CHANGEOVER TO SNOW DURING THE AFTERNOON...BUT ACCUMULATIONS WILL LIKELY BE AN INCH OR LESS AND MOSTLY CONFINED TO THE HIGHER ELEVATIONS. LOOK FOR TEMPERATURES TO START OUT TUESDAY MORNING IN THE 50S EAST AND NEAR 40 FAR WEST...REACHING BY EVENING THE LOW TO MID 30S MOST OF THE LOW LANDS AND BELOW FREEZING ABOVE 2000 FEET. WHILE SNOW SHOWERS TAPER OFF EARLY TUESDAY NIGHT IN THE MOUNTAINS... CLEARING FOLLOWS MORE SLOWLY WITH THE COLD ADVECTION AND UPSLOPE FLOW IN THE MOUNTAINS. STILL...IT SHOULD BECOME MOSTLY CLEAR EARLY ENOUGH AS DRY HIGH PRESSURE BUILDS IN RAPIDLY FROM THE WEST...AND ALLOW TEMPERATURES TO FALL WELL BELOW FREEZING IN ALL LOCATIONS. HOWEVER...BELIEVE THE MODELS MAY BE A BIT ON THE LOW SIDE AS THEY FORECAST A RUN FOR RECORD LOWS TUESDAY NIGHT. FOR NOW...WILL KEEP OUR MINS A COUPLE OF DEGREES ABOVE THE MOS...BUT STILL WELL BELOW FREEZING. THEREAFTER...HIGH PRESSURE SLIDES ACROSS WITH ABUNDANT SUNSHINE WEDNESDAY AND THURSDAY...ALONG WITH A WARMING TREND. WITH DRY AIR AND LIGHT WINDS WEDNESDAY NIGHT...TEMPERATURES COULD FALL BELOW FREEZING AGAIN. && .LONG TERM /FRIDAY THROUGH SUNDAY/... SW FLOW DOMINATES THROUGH FRIDAY BEFORE S/W TROF TRIES TO CREATE FOR AN UNSETTLED SATURDAY. DUE TO CONTINUED DIFFERENCES REGARDING AMPLITUDE AND STRENGTH OF SURFACE FEATURES...HAVE STAYED CLOSE TO WPC PREFERRED SOLUTION WITH THREAT FOR SHRA FRIDAY NIGHT AND SATURDAY. FOR TEMPS...A WARMING TREND WILL BE NOTED TO ROUND OUT THE WORK WEEK...BEFORE COOLER BUT MORE SEASONAL AIR ARRIVES FOR THE WEEKEND. && .AVIATION /08Z MONDAY THROUGH FRIDAY/... VFR EXPECTED AHEAD OF THE CONVECTION ASSOCIATED WITH A STRONG FRONTAL SYSTEM. CEILINGS WILL GRADUALLY LOWER...WITH CONVECTION ENTERING THE WESTERN TERMINALS AT AROUND 17Z-18Z. PREFERRING MVFR CONDITIONS TO PREVAIL WITH VCTS FOR NOW GIVEN THE ATMOSPHERIC SET UP. EXPECTING SOUTHERLY WINDS IN THE WARM SECTOR WHICH WILL TYPICALLY LEND TO HIGHER CEILINGS...EVEN IN SHRA/TSRA. TEMPOS WILL LIKELY BE NEEDED FOR BRIEF IFR VISIBILITIES. WILL REEVALUATE THE PREVAILING TSRA POTENTIAL FOR THE 12Z TAF ISSUANCE. SPEAKING OF VISIBILITIES...NOT EXPECTING BR/FG TO SETTLE IN BETWEEN ROUNDS OF SHRA/TSRA GIVEN THE STRONG GRADIENT WIND SET UP. MAY GET SOME GUSTS WITH THE CONVECTION...ALSO NECESSITATING TEMPOS AS WELL. COLD FRONT SHOULD NOT PASS BEFORE 06Z TUESDAY...SO WILL NOT SEE THE WIND DIRECTION SHIFT IN THIS PERIOD. FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z TUESDAY... FORECAST CONFIDENCE: HIGH THROUGH 18Z. MEDIUM AFTER. ALTERNATE SCENARIOS: CONVECTION TIMING AND BRIEF FLIGHT CATEGORY BOUNCES COULD LEAD TO TEMPOS AND AMENDMENTS. MAY NEED PREVAILING TSRA. EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY OF WFO FORECAST TO AVAILABLE MODEL INFORMATION: H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS. L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. DATE MON 04/14/14 UTC 1HRLY 08 09 10 11 12 13 14 15 16 17 18 19 EDT 1HRLY 04 05 06 07 08 09 10 11 12 13 14 15 CRW CONSISTENCY H H H H H H H H H H H H HTS CONSISTENCY H H H H H H H H H H H H BKW CONSISTENCY H H H H H H H H H H H H EKN CONSISTENCY H H H H H H H H H H H H PKB CONSISTENCY H H H H H H H H H H H H CKB CONSISTENCY H H H H H H H H H H H H AFTER 06Z TUESDAY... IFR CONDITIONS EXPECTED LATE MONDAY NIGHT UNDER MODERATE RAIN SHOWERS. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...NONE. OH...NONE. KY...NONE. VA...NONE. && $$ SYNOPSIS...JMV/26 NEAR TERM...26 SHORT TERM...JMV LONG TERM...30 AVIATION...26
AREA FORECAST DISCUSSION
NWS NORMAN OK
1241 PM CDT MON APR 14 2014 .AVIATION... VFR CEILINGS WILL SCATTERED ACROSS CENTRAL OKLAHOMA THIS AFTERNOON WITH GUSTY NORTH WINDS PREVAILING. SKIES WILL BE MAINLY CLEAR TONIGHT WITH LIGHT NORTH WINDS BECOMING SOUTHWEST IN WESTERN OKLAHOMA EARLY TUESDAY. && .PREV DISCUSSION... /ISSUED 1011 AM CDT MON APR 14 2014/ UPDATE... UPDATE TO PRECIP FORECAST... DISCUSSION... LIGHT SNOW CONTINUES TO FALL ACROSS PORTIONS OF NRN AND CENTRAL OK... WITH AN AREA OF SNOW SLOWLY MOVING E/SE ACROSS PORTIONS OF THE OKC METRO. IMPACTS ARE EXPECTED TO BE LIMITED... OKDOT TRAFFIC CAMS AND REPORTS VIA SOCIAL MEDIA SHOW LIGHT SNOW FALLING... WITH VISIBILITIES DROPPING NEAR 1 TO 1 1/2 MILES. UPDATED FORECAST TO REFLECT CURRENT PATH OF SNOW... WITH -RA/SN MIX POSSIBLE SOUTH OF THE I-44/40 CORRIDOR... CONSIDERING SFC/BL TEMPS AND RECENT 15Z OBS FROM KCSM AND KHBR... REPORTING UNKNOWN PRECIP. RAP BUFR SOUNDINGS SHOW BL TEMPS WARMING SLOWLY THROUGH NOON... WITH DRIER AIR MOVING IN AS THE SFC HIGH ACROSS KS CONTINUES TO SINK SWRD ACROSS THE SRN PLAINS. EFFECTS OF THIS ARE ALREADY BEING SEEN ACROSS FAR NWRN OK. PRECIP... SN... RA/SN WILL CONTINUE AHEAD OF THE SFC HIGH... WHERE A DECENT REGION OF ISENTROPIC ASCENT RESIDES WITHIN THE 290-295K LEVEL... SYNONYMOUS WITH THE BEST MOISTURE WITHIN THE 850 TO 700 MB LEVEL. PRECIP WILL CONTINUE TO EXIT TO THE EAST THROUGH NOON... AS THE H500 TROUGH CONTINUES TO TRACK EWRD AND THE SFC HIGH SETTLES INTO THE REGION THIS AFTN. JTK PREV DISCUSSION... /ISSUED 618 AM CDT MON APR 14 2014/ AVIATION... MVFR CIGS WILL REMAIN WIDESPREAD THROUGH THE EARLY MORNING. LIGHT RAIN/SNOW WILL CONTINUE TO MOVE THROUGH NRN HALF OF OK THIS AM. CIG/VSBYS MAY DROP TO IFR BRIEFLY AT NRN SITES AS THE HEAVIER PRCP MOVES THROUGH. PRECIP SHOULD END BY LATE MORNING WITH CONDITIONS IMPROVING TO VFR BY AFTN. STRONG N WINDS WITH FREQUENT GUSTS OVER 30 KTS WILL PERSIST THROUGH THE DAY...BUT SHOULD DIMINISH RAPIDLY EARLY THIS EVENING. PREV DISCUSSION... /ISSUED 404 AM CDT MON APR 14 2014/ DISCUSSION... BAND OF SNOW FROM TX PANHANDLE INTO NW CORNER OF THE FA CONTINUES TO MOVE STEADILY EWD. SNOWFALL RATES IN THIS BAND SUFFICIENT FOR SOME LIGHT ACCUMS DESPITE WARM GROUND TEMPS AND AIR TEMPS RIGHT AT OR SLIGHTLY ABOVE FREEZING. WILL CONTINUE THE WINTER WX ADVY THROUGH THE EARLY MORNING. BEST CHANCES FOR PRECIP WILL REMAIN ACROSS THE NRN HALF OF THE FA THIS MORNING AS MID LEVEL TROUGH MOVES THROUGH. TEMP PROFILES WILL BE COLD ENOUGH FOR SNOW OR RAIN/SNOW MIX OVER MUCH OF THE NRN HALF OF THE FA THIS MORNING. PRECIP SHOULD SHUT OFF BY AFTERNOON AS TROUGH TRANSLATES INTO ERN OK. STRONG NORTH WINDS WILL CONTINUE THROUGH TODAY AND WILL LEAVE WIND ADVY IN PLACE. WINDS WILL DROP OFF QUICKLY THIS EVENING AND REMAIN LIGHT OVERNIGHT AS SURFACE RIDGE SETTLES OVER THE SRN PLAINS. WITH MOSTLY CLEAR SKIES AND LIGHT WINDS A COLD NIGHT IS IN STORE WITH BELOW FREEZING TEMPS EXPECTED AREAWIDE AND FREEZE/HARD FREEZE WARNINGS ARE IN EFFECT. WARMER TEMPS EXPECTED TUESDAY WITH THE RETURN OF SLY LOW LEVEL FLOW. ANOTHER S/W TROUGH MOVES IN FROM THE NW AROUND MIDWEEK BRINGING RAIN CHANCES AND ANOTHER FRONT. DRY WEATHER EXPECTED FRIDAY AND SATURDAY WITH PRECIP CHANCES RETURNING LATE IN THE WEEKEND AS SYSTEM APPROACHES FROM THE SOUTHWESTERN U.S. && .PRELIMINARY POINT TEMPS/POPS... OKLAHOMA CITY OK 29 61 39 66 / 0 0 0 0 HOBART OK 24 63 39 69 / 0 0 0 0 WICHITA FALLS TX 29 63 39 70 / 0 0 0 0 GAGE OK 22 66 41 71 / 0 0 0 0 PONCA CITY OK 24 61 39 67 / 0 0 0 0 DURANT OK 31 60 38 64 / 0 0 0 0 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...HARD FREEZE WARNING FROM 1 AM TO 9 AM CDT TUESDAY FOR OKZ004>025- 027-033>038-044. FREEZE WARNING FROM 1 AM TO 9 AM CDT TUESDAY FOR OKZ026-028>032- 039>043-045>048-050>052. TX...HARD FREEZE WARNING FROM 1 AM TO 9 AM CDT TUESDAY FOR TXZ083>089. FREEZE WARNING FROM 1 AM TO 9 AM CDT TUESDAY FOR TXZ090. && $$
AREA FORECAST DISCUSSION
NWS NORMAN OK
1011 AM CDT MON APR 14 2014 .UPDATE... UPDATE TO PRECIP FORECAST... && .DISCUSSION... LIGHT SNOW CONTINUES TO FALL ACROSS PORTIONS OF NRN AND CENTRAL OK... WITH AN AREA OF SNOW SLOWLY MOVING E/SE ACROSS PORTIONS OF THE OKC METRO. IMPACTS ARE EXPECTED TO BE LIMITED... OKDOT TRAFFIC CAMS AND REPORTS VIA SOCIAL MEDIA SHOW LIGHT SNOW FALLING... WITH VISIBILITIES DROPPING NEAR 1 TO 1 1/2 MILES. UPDATED FORECAST TO REFLECT CURRENT PATH OF SNOW... WITH -RA/SN MIX POSSIBLE SOUTH OF THE I-44/40 CORRIDOR... CONSIDERING SFC/BL TEMPS AND RECENT 15Z OBS FROM KCSM AND KHBR... REPORTING UNKNOWN PRECIP. RAP BUFR SOUNDINGS SHOW BL TEMPS WARMING SLOWLY THROUGH NOON... WITH DRIER AIR MOVING IN AS THE SFC HIGH ACROSS KS CONTINUES TO SINK SWRD ACROSS THE SRN PLAINS. EFFECTS OF THIS ARE ALREADY BEING SEEN ACROSS FAR NWRN OK. PRECIP... SN... RA/SN WILL CONTINUE AHEAD OF THE SFC HIGH... WHERE A DECENT REGION OF ISENTROPIC ASCENT RESIDES WITHIN THE 290-295K LEVEL... SYNONYMOUS WITH THE BEST MOISTURE WITHIN THE 850 TO 700 MB LEVEL. PRECIP WILL CONTINUE TO EXIT TO THE EAST THROUGH NOON... AS THE H500 TROUGH CONTINUES TO TRACK EWRD AND THE SFC HIGH SETTLES INTO THE REGION THIS AFTN. JTK && .PREV DISCUSSION... /ISSUED 618 AM CDT MON APR 14 2014/ AVIATION... MVFR CIGS WILL REMAIN WIDESPREAD THROUGH THE EARLY MORNING. LIGHT RAIN/SNOW WILL CONTINUE TO MOVE THROUGH NRN HALF OF OK THIS AM. CIG/VSBYS MAY DROP TO IFR BRIEFLY AT NRN SITES AS THE HEAVIER PRCP MOVES THROUGH. PRECIP SHOULD END BY LATE MORNING WITH CONDITIONS IMPROVING TO VFR BY AFTN. STRONG N WINDS WITH FREQUENT GUSTS OVER 30 KTS WILL PERSIST THROUGH THE DAY...BUT SHOULD DIMINISH RAPIDLY EARLY THIS EVENING. PREV DISCUSSION... /ISSUED 404 AM CDT MON APR 14 2014/ DISCUSSION... BAND OF SNOW FROM TX PANHANDLE INTO NW CORNER OF THE FA CONTINUES TO MOVE STEADILY EWD. SNOWFALL RATES IN THIS BAND SUFFICIENT FOR SOME LIGHT ACCUMS DESPITE WARM GROUND TEMPS AND AIR TEMPS RIGHT AT OR SLIGHTLY ABOVE FREEZING. WILL CONTINUE THE WINTER WX ADVY THROUGH THE EARLY MORNING. BEST CHANCES FOR PRECIP WILL REMAIN ACROSS THE NRN HALF OF THE FA THIS MORNING AS MID LEVEL TROUGH MOVES THROUGH. TEMP PROFILES WILL BE COLD ENOUGH FOR SNOW OR RAIN/SNOW MIX OVER MUCH OF THE NRN HALF OF THE FA THIS MORNING. PRECIP SHOULD SHUT OFF BY AFTERNOON AS TROUGH TRANSLATES INTO ERN OK. STRONG NORTH WINDS WILL CONTINUE THROUGH TODAY AND WILL LEAVE WIND ADVY IN PLACE. WINDS WILL DROP OFF QUICKLY THIS EVENING AND REMAIN LIGHT OVERNIGHT AS SURFACE RIDGE SETTLES OVER THE SRN PLAINS. WITH MOSTLY CLEAR SKIES AND LIGHT WINDS A COLD NIGHT IS IN STORE WITH BELOW FREEZING TEMPS EXPECTED AREAWIDE AND FREEZE/HARD FREEZE WARNINGS ARE IN EFFECT. WARMER TEMPS EXPECTED TUESDAY WITH THE RETURN OF SLY LOW LEVEL FLOW. ANOTHER S/W TROUGH MOVES IN FROM THE NW AROUND MIDWEEK BRINGING RAIN CHANCES AND ANOTHER FRONT. DRY WEATHER EXPECTED FRIDAY AND SATURDAY WITH PRECIP CHANCES RETURNING LATE IN THE WEEKEND AS SYSTEM APPROACHES FROM THE SOUTHWESTERN U.S. && .PRELIMINARY POINT TEMPS/POPS... OKLAHOMA CITY OK 47 29 61 39 / 90 0 0 0 HOBART OK 49 24 63 39 / 50 0 0 0 WICHITA FALLS TX 51 29 63 39 / 10 0 0 0 GAGE OK 45 22 66 41 / 40 0 0 0 PONCA CITY OK 46 24 61 39 / 90 0 0 0 DURANT OK 49 31 60 38 / 30 0 0 0 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...HARD FREEZE WARNING FROM 1 AM TO 9 AM CDT TUESDAY FOR OKZ004>025- 027-033>038-044. WIND ADVISORY UNTIL NOON CDT TODAY FOR OKZ004>031-033>041- 044>046-050. WINTER WEATHER ADVISORY UNTIL 11 AM CDT THIS MORNING FOR OKZ004- 005-009-010-014. FREEZE WARNING FROM 1 AM TO 9 AM CDT TUESDAY FOR OKZ026-028>032- 039>043-045>048-050>052. TX...HARD FREEZE WARNING FROM 1 AM TO 9 AM CDT TUESDAY FOR TXZ083>089. WIND ADVISORY UNTIL NOON CDT TODAY FOR TXZ083>090. FREEZE WARNING FROM 1 AM TO 9 AM CDT TUESDAY FOR TXZ090. && $$
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1039 AM EDT MON APR 14 2014 .SYNOPSIS... AFTER ANOTHER MILD DAY...A FRONTAL SYSTEM WILL APPROACH THE AREA TONIGHT...AND PASS THROUGH THE REGION TUESDAY. BELOW NORMAL TEMPERATURES WILL FOLLOW THE FRONT AND LAST THROUGH MID- WEEK...WITH A GRADUAL MODERATION TOWARD THE END OF THE WEEK. && .NEAR TERM /THROUGH TONIGHT/... SATELLITE IMAGERY AND SFC OBS SHOW PLENTY OF MID AND HIGH CLOUDS STREAMING NE OVER THE AREA...ESPECIALLY WESTERN LOCATIONS. IT WILL BE ANOTHER VERY MILD DAY...BUT WITH MORE IN THE WAY OF CLOUDINESS...EXPECT TODAYS HIGHS TO REMAIN BELOW THOSE OF YESTERDAY IN MOST AREAS. LATEST RADAR IMAGERY SHOWS BEST RETURNS JUST REACHING THE OHIO/PA BORDER. A FEW SPRINKLES MAY MAKE IT INTO WRN CWA THIS AFTERNOON BUT THE BETTER THE CHANCE FOR A STRAY SHOWER OR EVEN A THUNDERSTORM WILL BE LATER THIS AFTERNOON. THE OPERATIONAL MODELS ALL SPLASH AROUND A FAIR AMOUNT OF LIGHT QPF THIS AFTERNOON...AND THE SREF/GEFS EVEN SHOW A DECENT CHANCE OF MEASURABLE PRECIP...THOUGH THE PROBABILITIES OF MORE THAN ABOUT A TENTH ARE PRETTY SMALL. THE HIGH RES NMM/ARW AND HRRR ALL KEEP THE BULK OF THE FCST AREA MAINLY DRY THROUGH AT LEAST 20Z. THEY ALSO AGREE ON GENERATING A LINE OF CONVECTION WHICH SHOULD BE ENTERING MY WESTERN ZONES BY AROUND NIGHTFALL. SPC DOES NOT OUTLOOK US FOR SEVERE AND INSTABILITY WILL BE LIMITED...BUT WITH STRONG WINDS ALOFT...I WOULDN`T BE SURPRISED TO SEE A FEW THUNDERSTORMS ACCOMPANIED BY GUSTY WINDS INTO THE EVENING HOURS. THE TIMING OF THE CONVECTION INDICATED BY THE HIGH RES MODELS WOULD SUGGEST THAT THE SHOWERS WILL TEND TO RUN OUT OF GAS AS THEY HEAD EAST AFTER THE SUN GOING DOWN. REGARDLESS WE WILL SEE OCCASIONAL RAIN AND SHOWERS CONTINUE INTO TUESDAY. THE TIGHT TEMPERATURE GRADIENT ASSOCIATED WITH THE FRONT MEANS THERE WILL BE A BIG BUST POTENTIAL FOR THE OVERNIGHT LOW. IF THE FRONT IS FAST...LOWS OVER THE NW COULD BE MUCH COOLER THAN I CURRENTLY PORTRAY. && .SHORT TERM /TUESDAY/... THE FRONT WILL MOVE ACROSS THE AREA TUESDAY...ALONG WITH THE SAME BIG TEMP BUST POTENTIAL OF TONIGHT. MODEL THERMAL FIELDS SHOW A VERY TIGHT PACKING OF THE COLD AIR JUST BEHIND THE FRONT SO SMALL TIMING PROBLEMS WILL MEAN RELATIVELY BIG TEMP SWINGS AS THE SYSTEM SLIDES EAST. A COUPLE OF OTHER CONCERNS FOR TUESDAY INCLUDE THE POTENTIAL FOR A NARROW COLD FRONTAL RAINBAND TO FORM...AS WELL AS HOW MUCH IF ANY SNOW MANAGES TO ACCUMULATE ON THE COLD AIR SIDE OF THE WAVY COLD FRONT. AS THE UPPER TROUGH TAKES ON A NEGATIVE TILT AND SWINGS THROUGH...WE HAVE SEEN IN THE PAST THESE FRONTS TAKE ON STRONG ANAFRONT CHARACTERISTICS INCLUDING A NARROW LINE OF CONVECTION AND LOCALIZED STRONG GUSTY WINDS AS PROGGED 850-500MB WINDS ON THE ORDER OF 45-60KT MIX DOWN IN SOME OF THE STRONGER CONVECTION. THEN THE...SNOW...YUK! COLD AIR MOVING INTO THE AREA BEHIND THE FRONT SHOULD CAUSE RAIN TO MIX WITH/CHANGEOVER TO WET SNOW ACROSS THE WESTERN AND CENTRAL MOUNTAINS TUESDAY INTO TUESDAY NIGHT. AT THIS TIME...I AM THINKING THAT THE PRECIP WILL BE WINDING DOWN RATHER QUICKLY TUESDAY AFTERNOON INTO THE EVENING...MEANING THE CHANGE- OVER WILL BE OCCURRING DURING THE DAY FOR THE MOST PART WHICH IS USUALLY VITAL AT THIS TIME OF THE YEAR. STILL CAN`T RULE OUT A COATING TO A COUPLE OF SLUSHY INCHES OF SNOW...WHICH COULD RESULT IN HAZARDOUS TRAVEL AND ROAD CONDITIONS. THE BEST CHANCE FOR A FEW INCHES OF WET SNOW WILL BE OVER THE HIGHEST ELEVATIONS IN THE WESTERN ALLEGHENIES. NO HEADLINES ARE PLANNED AT THIS POINT...BUT THE POTENTIAL HAS BEEN ADDRESSED IN OUR HWO. && .LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... GROWING SEASON TECHNICALLY STARTS TUESDAY OVER MY SERN ZONES. AFTER SOME COORDINATION WITH SURROUNDING OFFICES...HAVE AGREED TO LEAN AWAY FROM ANY FROST/FREEZE HEADLINES...BUT THE LOWS WILL LIKELY SUPPORT A FREEZE WATCH/WARNING BEING ISSUED AT SOME POINT TODAY. THE LAST OF THE SHOWERS WILL BE LEAVING THE REGION TUESDAY EVENING LEADING THE WAY TO A FEW FAIR BUT ABNORMALLY CHILLY DAYS FROM WEDNESDAY INTO THE END OF THE WEEK. RISING HEIGHTS/SW FLOW ALOFT OVER THE EASTERN US IN RESPONSE TO FCST TROUGHING OVER THE N-CENTRAL PLAINS SHOULD ALLOW FOR TEMPERATURES TO REBOUND TOWARD THE WEEKEND. && .AVIATION /15Z MONDAY THROUGH FRIDAY/... BREEZY CONDITIONS AND A DRY AIRMASS KEEPING CONDITIONS VFR. EXPECT THIS TO BE THE CASE FOR MOST OF THE DAY. COLD FRONT STILL WELL TO THE WEST...NEAR LAKE MI. CONVECTION TO THE SOUTH IS THE MAIN PLAYER AT THE CURRENT TIME...AS THE NORTHERN SECTION OF THE FRONT IS NOT REAL ACTIVE AT THIS POINT. VAD WINDS STILL 35 TO 40 KNOTS. HAVE LLWS IN TAFS. SHOWERS WILL BECOME MORE WIDESPREAD AFTER SUNSET INTO TUE. SOME CHC OF THUNDER...BUT MUCH OF THE RAIN WILL BE ON THE COLD SIDE OF THE FRONT. ALSO DEWPOINTS NOT FCST TO BE THAT HIGH...AND THE THERMAL RIDGE IS EXPECTED TO BE EAST OF OUR AREA. GUSTY NORTH WINDS EXPECTED FROM TUE AFT...INTO WED AM. VERY STRONG COLD ADVECTION...THUS RAIN WILL LIKELY CHANGE TO SNOW BEFORE ENDING TUESDAY NIGHT. WED INTO FRIDAY LOOKS OK AT THIS POINT. OUTLOOK... -TUE...RAIN/REDUCED CIGS...ENDING AS A BRIEF PERIOD OF WET SNOW ACROSS THE NORTHERN AND WESTERN MTNS. .WED-THU...VFR. .FRI...VFR. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...LA CORTE NEAR TERM...LA CORTE/GARTNER SHORT TERM...LA CORTE LONG TERM...LA CORTE AVIATION...GARTNER/MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
643 AM EDT MON APR 14 2014 .SYNOPSIS... AFTER ANOTHER MILD DAY...A FRONTAL SYSTEM WILL APPROACH THE AREA TONIGHT...AND PASS THROUGH THE REGION TUESDAY. BELOW NORMAL TEMPERATURES WILL FOLLOW THE FRONT AND LAST THROUGH MID- WEEK...WITH A GRADUAL MODERATION TOWARD THE END OF THE WEEK. && .NEAR TERM /THROUGH TONIGHT/... SATELLITE SHOWS PLENTY OF MID AND HIGH CLOUDS STREAMING NE OVER THE AREA...ESPECIALLY WESTERN LOCATIONS. IT WILL BE ANOTHER VERY MILD DAY...BUT WITH MORE IN THE WAY OF CLOUDINESS...WE SHOULD KNOCK A FEW DEGREES OFF YESTERDAY`S HIGHS IN MOST AREAS. THE DEEPER WE GET INTO THE DAY THE BETTER THE CHANCE WILL BE FOR A STRAY SHOWER OR EVEN A THUNDERSTORM. THE OPERATIONAL MODELS ALL SPLASH AROUND A FAIR AMOUNT OF LIGHT QPF THIS AFTERNOON...AND THE SREF/GEFS EVEN SHOW A DECENT CHANCE OF MEASURABLEPRECIP...THOUGH THE PROBABILITIES OF MORE THAN ABOUT A TENTH ARE PRETTY SMALL. THE HIGH RES NMM/ARW AND HRRR ALL KEEP THE BULK OF THE FCST AREA MAINLY DRY THROUGH AT LEAST 20Z. THEY ALSO AGREE ON GENERATING A LINE OF CONVECTION WHICH SHOULD BE ENTERING MY WESTERN ZONES BY AROUND NIGHTFALL. SPC DOES NOT OUTLOOK US FOR SEVERE AND INSTABILITY WILL BE LIMITED...BUT WITH STRONG WINDS ALOFT...I WOULDN`T BE SURPRISED TO SEE A FEW THUNDERSTORMS ACCOMPANIED BY GUSTY WINDS INTO THE EVENING HOURS. THE TIMING OF THE CONVECTION INDICATED BY THE HIGH RES MODELS WOULD SUGGEST THAT THE SHOWERS WILL TEND TO RUN OUT OF GAS AS THEY HEAD EAST AFTER THE SUN GOING DOWN. REGARDLESS WE WILL SEE OCCASIONALRAIN AND SHOWERS CONTINUE INTO TUESDAY. THE TIGHT TEMPERATURE GRADIENT ASSOCIATED WITH THE FRONT MEANS THERE WILL BE A BIG BUST POTENTIAL FOR THE OVERNIGHT LOW. IF THE FRONT IS FAST...LOWS OVER THE NW COULD BE MUCH COOLER THAN I CURRENTLY PORTRAY. && .SHORT TERM /TUESDAY/... THE FRONT WILL MOVE ACROSS THE AREA TUESDAY...ALONG WITH THE SAME BIG TEMP BUST POTENTIAL OF TONIGHT. MODEL THERMAL FIELDS SHOW A VERY TIGHT PACKING OF THE COLD AIR JUST BEHIND THE FRONT SO SMALL TIMING PROBLEMS WILL MEAN RELATIVELY BIG TEMP SWINGS AS THE SYSTEM SLIDES EAST. A COUPLE OF OTHER CONCERNS FOR TUESDAY INCLUDE THE POTENTIAL FOR A NARROW COLD FRONTAL RAINBAND TO FORM...AS WELL AS HOW MUCH IF ANY SNOW MANAGES TO ACCUMULATE ON THE COLD AIR SIDE OF THE WAVY COLD FRONT. AS THE UPPER TROUGH TAKES ON A NEGATIVE TILT AND SWINGS THROUGH...WE HAVE SEEN IN THE PAST THESE FRONTS TAKE ON STRONG ANAFRONT CHARACTERISTICS INCLUDING A NARROW LINE OF CONVECTION AND LOCALIZED STRONG GUSTY WINDS AS PROGGED 850-500MB WINDS ON THE ORDER OF 45-60KT MIX DOWN IN SOME OF THE STRONGER CONVECTION. THEN THE...SNOW...YUK! COLD AIR MOVING INTO THE AREA BEHIND THE FRONT SHOULD CAUSE RAIN TO MIX WITH/CHANGEOVER TO WET SNOW ACROSS THE WESTERN AND CENTRAL MOUNTAINS TUESDAY INTO TUESDAY NIGHT. AT THIS TIME...I AM THINKING THAT THE PRECIP WILL BE WINDING DOWN RATHER QUICKLY TUESDAY AFTERNOON INTO THE EVENING...MEANING THE CHANGE- OVER WILL BE OCCURRING DURING THE DAY FOR THE MOST PART WHICH IS USUALLY VITAL AT THIS TIME OF THE YEAR. STILL CAN`T RULE OUT A COATING TO A COUPLE OF SLUSHY INCHES OF SNOW...WHICH COULD RESULT IN HAZARDOUS TRAVEL AND ROAD CONDITIONS. THE BEST CHANCE FOR A FEW INCHES OF WET SNOW WILL BE OVER THE HIGHEST ELEVATIONS IN THE WESTERN ALLEGHENIES. NO HEADLINES ARE PLANNED AT THIS POINT...BUT THE POTENTIAL HAS BEEN ADDRESSED IN OUR HWO. && .LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... GROWING SEASON TECHNICALLY STARTS TUESDAY OVER MY SERN ZONES. AFTER SOME COORDINATION WITH SURROUNDING OFFICES...HAVE AGREED TO LEAN AWAY FROM ANY FROST/FREEZE HEADLINES...BUT THE LOWS WILL LIKELY SUPPORT A FREEZE WATCH/WARNING BEING ISSUED AT SOME POINT TODAY. THE LAST OF THE SHOWERS WILL BE LEAVING THE REGION TUESDAY EVENING LEADING THE WAY TO A FEW FAIR BUT ABNORMALLY CHILLY DAYS FROM WEDNESDAY INTO THE END OF THE WEEK. RISING HEIGHTS/SW FLOW ALOFT OVER THE EASTERN US IN RESPONSE TO FCST TROUGHING OVER THE N-CENTRAL PLAINS SHOULD ALLOW FOR TEMPERATURES TO REBOUND TOWARD THE WEEKEND. && .AVIATION /12Z MONDAY THROUGH FRIDAY/... BREEZY CONDITIONS AND A DRY AIRMASS KEEPING CONDITIONS VFR. EXPECT THIS TO BE THE CASE FOR MOST OF THE DAY. COLD FRONT STILL WELL TO THE WEST...NEAR LAKE MI. CONVECTION TO THE SOUTH IS THE MAIN PLAYER AT THE CURRENT TIME...AS THE NORTHERN SECTION OF THE FRONT IS NOT REAL ACTIVE AT THIS POINT. VAD WINDS STILL 35 TO 40 KNOTS. HAVE LLWS IN TAFS. SHOWERS WILL BECOME MORE WIDESPREAD AFTER SUNSET INTO TUE. SOME CHC OF THUNDER...BUT MUCH OF THE RAIN WILL BE ON THE COLD SIDE OF THE FRONT. ALSO DEWPOINTS NOT FCST TO BE THAT HIGH...AND THE THERMAL RIDGE IS EXPECTED TO BE EAST OF OUR AREA. GUSTY NORTH WINDS EXPECTED FROM TUE AFT...INTO WED AM. VERY STRONG COLD ADVECTION...THUS RAIN WILL LIKELY CHANGE TO SNOW BEFORE ENDING TUESDAY NIGHT. WED INTO FRIDAY LOKKS OK AT THIS POINT. OUTLOOK... -TUE...RAIN/REDUCED CIGS...ENDING AS A BRIEF PERIOD OF WET SNOW ACROSS THE NORTHERN AND WESTERN MTNS. .WED-THU...VFR. .FRI...VFR. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...LA CORTE NEAR TERM...LA CORTE SHORT TERM...LA CORTE LONG TERM...LA CORTE AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
542 AM EDT MON APR 14 2014 .SYNOPSIS... AFTER ANOTHER MILD DAY...A FRONTAL SYSTEM WILL APPROACH THE AREA TONIGHT...AND PASS THROUGH THE REGION TUESDAY. BELOW NORMAL TEMPERATURES WILL FOLLOW THE FRONT AND LAST THROUGH MID- WEEK...WITH A GRADUAL MODERATION TOWARD THE END OF THE WEEK. && .NEAR TERM /THROUGH TONIGHT/... SATELLITE SHOWS PLENTY OF MID AND HIGH CLOUDS STREAMING NE OVER THE AREA...ESPECIALLY WESTERN LOCATIONS. IT WILL BE ANOTHER VERY MILD DAY...BUT WITH MORE IN THE WAY OF CLOUDINESS...WE SHOULD KNOCK A FEW DEGREES OFF YESTERDAY`S HIGHS IN MOST AREAS. THE DEEPER WE GET INTO THE DAY THE BETTER THE CHANCE WILL BE FOR A STRAY SHOWER OR EVEN A THUNDERSTORM. THE OPERATIONAL MODELS ALL SPLASH AROUND A FAIR AMOUNT OF LIGHT QPF THIS AFTERNOON...AND THE SREF/GEFS EVEN SHOW A DECENT CHANCE OF MEASURABLEPRECIP...THOUGH THE PROBABILITIES OF MORE THAN ABOUT A TENTH ARE PRETTY SMALL. THE HIGH RES NMM/ARW AND HRRR ALL KEEP THE BULK OF THE FCST AREA MAINLY DRY THROUGH AT LEAST 20Z. THEY ALSO AGREE ON GENERATING A LINE OF CONVECTION WHICH SHOULD BE ENTERING MY WESTERN ZONES BY AROUND NIGHTFALL. SPC DOES NOT OUTLOOK US FOR SEVERE AND INSTABILITY WILL BE LIMITED...BUT WITH STRONG WINDS ALOFT...I WOULDN`T BE SURPRISED TO SEE A FEW THUNDERSTORMS ACCOMPANIED BY GUSTY WINDS INTO THE EVENING HOURS. THE TIMING OF THE CONVECTION INDICATED BY THE HIGH RES MODELS WOULD SUGGEST THAT THE SHOWERS WILL TEND TO RUN OUT OF GAS AS THEY HEAD EAST AFTER THE SUN GOING DOWN. REGARDLESS WE WILL SEE OCCASIONALRAIN AND SHOWERS CONTINUE INTO TUESDAY. THE TIGHT TEMPERATURE GRADIENT ASSOCIATED WITH THE FRONT MEANS THERE WILL BE A BIG BUST POTENTIAL FOR THE OVERNIGHT LOW. IF THE FRONT IS FAST...LOWS OVER THE NW COULD BE MUCH COOLER THAN I CURRENTLY PORTRAY. && .SHORT TERM /TUESDAY/... THE FRONT WILL MOVE ACROSS THE AREA TUESDAY...ALONG WITH THE SAME BIG TEMP BUST POTENTIAL OF TONIGHT. MODEL THERMAL FIELDS SHOW A VERY TIGHT PACKING OF THE COLD AIR JUST BEHIND THE FRONT SO SMALL TIMING PROBLEMS WILL MEAN RELATIVELY BIG TEMP SWINGS AS THE SYSTEM SLIDES EAST. A COUPLE OF OTHER CONCERNS FOR TUESDAY INCLUDE THE POTENTIAL FOR A NARROW COLD FRONTAL RAINBAND TO FORM...AS WELL AS HOW MUCH IF ANY SNOW MANAGES TO ACCUMULATE ON THE COLD AIR SIDE OF THE WAVY COLD FRONT. AS THE UPPER TROUGH TAKES ON A NEGATIVE TILT AND SWINGS THROUGH...WE HAVE SEEN IN THE PAST THESE FRONTS TAKE ON STRONG ANAFRONT CHARACTERISTICS INCLUDING A NARROW LINE OF CONVECTION AND LOCALIZED STRONG GUSTY WINDS AS PROGGED 850-500MB WINDS ON THE ORDER OF 45-60KT MIX DOWN IN SOME OF THE STRONGER CONVECTION. THEN THE...SNOW...YUK! COLD AIR MOVING INTO THE AREA BEHIND THE FRONT SHOULD CAUSE RAIN TO MIX WITH/CHANGEOVER TO WET SNOW ACROSS THE WESTERN AND CENTRAL MOUNTAINS TUESDAY INTO TUESDAY NIGHT. AT THIS TIME...I AM THINKING THAT THE PRECIP WILL BE WINDING DOWN RATHER QUICKLY TUESDAY AFTERNOON INTO THE EVENING...MEANING THE CHANGE- OVER WILL BE OCCURRING DURING THE DAY FOR THE MOST PART WHICH IS USUALLY VITAL AT THIS TIME OF THE YEAR. STILL CAN`T RULE OUT A COATING TO A COUPLE OF SLUSHY INCHES OF SNOW...WHICH COULD RESULT IN HAZARDOUS TRAVEL AND ROAD CONDITIONS. THE BEST CHANCE FOR A FEW INCHES OF WET SNOW WILL BE OVER THE HIGHEST ELEVATIONS IN THE WESTERN ALLEGHENIES. NO HEADLINES ARE PLANNED AT THIS POINT...BUT THE POTENTIAL HAS BEEN ADDRESSED IN OUR HWO. && .LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... GROWING SEASON TECHNICALLY STARTS TUESDAY OVER MY SERN ZONES. AFTER SOME COORDINATION WITH SURROUNDING OFFICES...HAVE AGREED TO LEAN AWAY FROM ANY FROST/FREEZE HEADLINES...BUT THE LOWS WILL LIKELY SUPPORT A FREEZE WATCH/WARNING BEING ISSUED AT SOME POINT TODAY. THE LAST OF THE SHOWERS WILL BE LEAVING THE REGION TUESDAY EVENING LEADING THE WAY TO A FEW FAIR BUT ABNORMALLY CHILLY DAYS FROM WEDNESDAY INTO THE END OF THE WEEK. RISING HEIGHTS/SW FLOW ALOFT OVER THE EASTERN US IN RESPONSE TO FCST TROUGHING OVER THE N-CENTRAL PLAINS SHOULD ALLOW FOR TEMPERATURES TO REBOUND TOWARD THE WEEKEND. && .AVIATION /10Z MONDAY THROUGH FRIDAY/... STILL BREEZY IN SPOTS AS OF 5 AM. HAVE LLWS IN ALL SITES FOR THIS MORNING. MAINLY VFR TODAY. TOOK OUT LOWER CIGS AT LNS AND MDT EARLIER...GIVEN FLOW IS MORE SW INSTEAD OF SE. ALSO DEWPOINTS NOT REAL HIGH. BULK OF THE RAIN WILL BE AFTER SUNSET TODAY. NO BIG CHANGES MADE TO 09Z TAFS. EARLIER DISCUSSION BELOW. VFR CONDITIONS CONTINUE AT ALL LOCATION TONIGHT. WHILE THESE CONDITIONS WILL PRETTY MUCH PREVAIL MOST OF THE OVERNIGHT AND MONDAY...SOME MVFR CONDITIONS ARE EXPECTED LATE TONIGHT OVER THE LOWER SUSQUEHANNA AIRFIELDS OF KMDT AND KLNS. THERE MAY BE SOME OTHER PATCHY AREAS OF FOG AROUND OVERNIGHT AS WELL IN OTHER LOCATIONS...BUT AT THIS POINT SEEMS PATCHY ENOUGH NOT TO INCLUDE IN OTHER TAFS. ADDITIONALLY...LLWS CONDITIONS CONTINUE OVER CENTRAL AND EASTERN TAFS TONIGHT AS SURFACE WINDS DECOUPLE...GENERALLY REDUCING TO UNDER 10 KNOTS. SHORT RANGE MODELS CONTINUE TO SHOW A HEALTHY LOW LEVEL JET OF 35 TO 45 KNOTS FROM THE WSW OVERNIGHT. IN WESTERN AREAS...UPPER FLOW IS LIGHTER...MAINLY 20 KNOTS OR SO. THEREFORE DID NOT INCLUDE LLWS IN KJST AND KBFD. WHILE SHOWERS AND THUNDERSTORMS SHOULD BE APPROACHING FROM THE WEST TOMORROW...HAVE SLOWED THE ONSET OF LOWER CIGS AND VSBYS UNTIL AFTER 00Z. DID INTRODUCE VCSH TO WESTERN AIRFIELDS...AND WILL HAVE TO WATCH THE PROGRESSION OF PRECIPITATION TOMORROW. THERE IS A RISK THAT SOME RESTRICTIONS MAY WORK INTO KBFD SHORTLY BEFORE 00Z. CONDITIONS ACROSS THE REGION WILL DETERIORATE LATER MONDAY INTO TUESDAY WITH IFR CIGS AND REDUCED VSBY WITH PRECIPITATION MOVING IN. CONVECTIVE CELLS ARE POSSIBLE WITH THE COLD FRONT. OUTLOOK... .MON...MAINLY VFR...WITH LOWERING CLOUDS. RESTRICTIONS POSSIBLE IN THE WEST CLOSE TO 00Z. .MON NIGHT-TUE...RAIN/REDUCED CIGS POSSIBLE...POSSIBLY ENDING AS A BRIEF PERIOD OF WET SNOW ACROSS THE NORTHERN AND WESTERN MTNS. .WED-THU...VFR. .FRI...VFR. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...LA CORTE NEAR TERM...LA CORTE SHORT TERM...LA CORTE LONG TERM...LA CORTE AVIATION...JUNG/MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
457 AM EDT MON APR 14 2014 .SYNOPSIS... AFTER ANOTHER MILD DAY...A FRONTAL SYSTEM WILL APPROACH THE AREA TONIGHT...AND PASS THROUGH THE REGION TUESDAY. BELOW NORMAL TEMPERATURES WILL FOLLOW THE FRONT AND LAST THROUGH MID- WEEK...WITH A GRADUAL MODERATION TOWARD THE END OF THE WEEK. && .NEAR TERM /THROUGH TONIGHT/... SATELLITE SHOWS PLENTY OF MID AND HIGH CLOUDS STREAMING NE OVER THE AREA...ESPECIALLY WESTERN LOCATIONS. IT WILL BE ANOTHER VERY MILD DAY...BUT WITH MORE IN THE WAY OF CLOUDINESS...WE SHOULD KNOCK A FEW DEGREES OFF YESTERDAY`S HIGHS IN MOST AREAS. THE DEEPER WE GET INTO THE DAY THE BETTER THE CHANCE WILL BE FOR A STRAY SHOWER OR EVEN A THUNDERSTORM. THE OPERATIONAL MODELS ALL SPLASH AROUND A FAIR AMOUNT OF LIGHT QPF THIS AFTERNOON...AND THE SREF/GEFS EVEN SHOW A DECENT CHANCE OF MEASURABLEPRECIP...THOUGH THE PROBABILITIES OF MORE THAN ABOUT A TENTH ARE PRETTY SMALL. THE HIGH RES NMM/ARW AND HRRR ALL KEEP THE BULK OF THE FCST AREA MAINLY DRY THROUGH AT LEAST 20Z. THEY ALSO AGREE ON GENERATING A LINE OF CONVECTION WHICH SHOULD BE ENTERING MY WESTERN ZONES BY AROUND NIGHTFALL. SPC DOES NOT OUTLOOK US FOR SEVERE AND INSTABILITY WILL BE LIMITED...BUT WITH STRONG WINDS ALOFT...I WOULDN`T BE SURPRISED TO SEE A FEW THUNDERSTORMS ACCOMPANIED BY GUSTY WINDS INTO THE EVENING HOURS. THE TIMING OF THE CONVECTION INDICATED BY THE HIGH RES MODELS WOULD SUGGEST THAT THE SHOWERS WILL TEND TO RUN OUT OF GAS AS THEY HEAD EAST AFTER THE SUN GOING DOWN. REGARDLESS WE WILL SEE OCCASIONALRAIN AND SHOWERS CONTINUE INTO TUESDAY. THE TIGHT TEMPERATURE GRADIENT ASSOCIATED WITH THE FRONT MEANS THERE WILL BE A BIG BUST POTENTIAL FOR THE OVERNIGHT LOW. IF THE FRONT IS FAST...LOWS OVER THE NW COULD BE MUCH COOLER THAN I CURRENTLY PORTRAY. && .SHORT TERM /TUESDAY/... THE FRONT WILL MOVE ACROSS THE AREA TUESDAY...ALONG WITH THE SAME BIG TEMP BUST POTENTIAL OF TONIGHT. MODEL THERMAL FIELDS SHOW A VERY TIGHT PACKING OF THE COLD AIR JUST BEHIND THE FRONT SO SMALL TIMING PROBLEMS WILL MEAN RELATIVELY BIG TEMP SWINGS AS THE SYSTEM SLIDES EAST. A COUPLE OF OTHER CONCERNS FOR TUESDAY INCLUDE THE POTENTIAL FOR A NARROW COLD FRONTAL RAINBAND TO FORM...AS WELL AS HOW MUCH IF ANY SNOW MANAGES TO ACCUMULATE ON THE COLD AIR SIDE OF THE WAVY COLD FRONT. AS THE UPPER TROUGH TAKES ON A NEGATIVE TILT AND SWINGS THROUGH...WE HAVE SEEN IN THE PAST THESE FRONTS TAKE ON STRONG ANAFRONT CHARACTERISTICS INCLUDING A NARROW LINE OF CONVECTION AND LOCALIZED STRONG GUSTY WINDS AS PROGGED 850-500MB WINDS ON THE ORDER OF 45-60KT MIX DOWN IN SOME OF THE STRONGER CONVECTION. THEN THE...SNOW...YUK! COLD AIR MOVING INTO THE AREA BEHIND THE FRONT SHOULD CAUSE RAIN TO MIX WITH/CHANGEOVER TO WET SNOW ACROSS THE WESTERN AND CENTRAL MOUNTAINS TUESDAY INTO TUESDAY NIGHT. AT THIS TIME...I AM THINKING THAT THE PRECIP WILL BE WINDING DOWN RATHER QUICKLY TUESDAY AFTERNOON INTO THE EVENING...MEANING THE CHANGE- OVER WILL BE OCCURRING DURING THE DAY FOR THE MOST PART WHICH IS USUALLY VITAL AT THIS TIME OF THE YEAR. STILL CAN`T RULE OUT A COATING TO A COUPLE OF SLUSHY INCHES OF SNOW...WHICH COULD RESULT IN HAZARDOUS TRAVEL AND ROAD CONDITIONS. THE BEST CHANCE FOR A FEW INCHES OF WET SNOW WILL BE OVER THE HIGHEST ELEVATIONS IN THE WESTERN ALLEGHENIES. NO HEADLINES ARE PLANNED AT THIS POINT...BUT THE POTENTIAL HAS BEEN ADDRESSED IN OUR HWO. && .LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... GROWING SEASON TECHNICALLY STARTS TUESDAY OVER MY SERN ZONES. AFTER SOME COORDINATION WITH SURROUNDING OFFICES...HAVE AGREED TO LEAN AWAY FROM ANY FROST/FREEZE HEADLINES...BUT THE LOWS WILL LIKELY SUPPORT A FREEZE WATCH/WARNING BEING ISSUED AT SOME POINT TODAY. THE LAST OF THE SHOWERS WILL BE LEAVING THE REGION TUESDAY EVENING LEADING THE WAY TO A FEW FAIR BUT ABNORMALLY CHILLY DAYS FROM WEDNESDAY INTO THE END OF THE WEEK. RISING HEIGHTS/SW FLOW ALOFT OVER THE EASTERN US IN RESPONSE TO FCST TROUGHING OVER THE N-CENTRAL PLAINS SHOULD ALLOW FOR TEMPERATURES TO REBOUND TOWARD THE WEEKEND. && .AVIATION /08Z MONDAY THROUGH FRIDAY/... VFR CONDITIONS CONTINUE AT ALL LOCATION TONIGHT. WHILE THESE CONDITIONS WILL PRETTY MUCH PREVAIL MOST OF THE OVERNIGHT AND MONDAY...SOME MVFR CONDITIONS ARE EXPECTED LATE TONIGHT OVER THE LOWER SUSQUEHANNA AIRFIELDS OF KMDT AND KLNS. THERE MAY BE SOME OTHER PATCHY AREAS OF FOG AROUND OVERNIGHT AS WELL IN OTHER LOCATIONS...BUT AT THIS POINT SEEMS PATCHY ENOUGH NOT TO INCLUDE IN OTHER TAFS. ADDITIONALLY...LLWS CONDITIONS CONTINUE OVER CENTRAL AND EASTERN TAFS TONIGHT AS SURFACE WINDS DECOUPLE...GENERALLY REDUCING TO UNDER 10 KNOTS. SHORT RANGE MODELS CONTINUE TO SHOW A HEALTHY LOW LEVEL JET OF 35 TO 45 KNOTS FROM THE WSW OVERNIGHT. IN WESTERN AREAS...UPPER FLOW IS LIGHTER...MAINLY 20 KNOTS OR SO. THEREFORE DID NOT INCLUDE LLWS IN KJST AND KBFD. WHILE SHOWERS AND THUNDERSTORMS SHOULD BE APPROACHING FROM THE WEST TOMORROW...HAVE SLOWED THE ONSET OF LOWER CIGS AND VSBYS UNTIL AFTER 00Z. DID INTRODUCE VCSH TO WESTERN AIRFIELDS...AND WILL HAVE TO WATCH THE PROGRESSION OF PRECIPITATION TOMORROW. THERE IS A RISK THAT SOME RESTRICTIONS MAY WORK INTO KBFD SHORTLY BEFORE 00Z. CONDITIONS ACROSS THE REGION WILL DETERIORATE LATER MONDAY INTO TUESDAY WITH IFR CIGS AND REDUCED VSBY WITH PRECIPITATION MOVING IN. CONVECTIVE CELLS ARE POSSIBLE WITH THE COLD FRONT. OUTLOOK... .MON...MAINLY VFR...WITH LOWERING CLOUDS. RESTRICTIONS POSSIBLE IN THE WEST CLOSE TO 00Z. .MON NIGHT-TUE...RAIN/REDUCED CIGS POSSIBLE...POSSIBLY ENDING AS A BRIEF PERIOD OF WET SNOW ACROSS THE NORTHERN AND WESTERN MTNS. .WED-THU...VFR. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...LA CORTE NEAR TERM...LA CORTE SHORT TERM...LA CORTE LONG TERM...LA CORTE AVIATION...JUNG/MARTIN
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1237 PM CDT MON APR 14 2014 .UPDATE...ADDED AVIATION SECTION FOR 18Z TAF`S. && .AVIATION...BNA/CKV/CSV...DRIER AIR HAS MOVED INTO MIDDLE TENNESSEE BEHIND THIS MORNING`S SHOWERS. EVEN THOUGH CIGS REMAIN BELOW 3 KFT ACROSS A LARGE PART OF THE AREA, VERY LITTLE ACTIVE WEATHER IS OCCURRING AS OF NOW. SURFACE FRONT WILL EDGE INTO MIDDLE TENNESSEE DURING THE AFTERNOON, WITH A GRADUAL INCREASE IN RADAR ECHOES AS THE ATMOSPHERE DESTABILIZES SOMEWHAT. MOST OF THE ACTIVITY WILL HOLD OFF UNTIL AFTER 00Z, WITH IFR CIGS LASTING MOST OF THE NIGHT. WINDS WILL REMAIN GUSTY AT LEAST THROUGH 18Z TOMORROW. && .PREV DISCUSSION... /ISSUED 1128 AM CDT MON APR 14 2014/ UPDATE...COLD FRONT HAS NOSED INTO WESTERN KY, ALTHOUGH RADAR MOSAIC CONTINUES TO SHOW LITTLE ACTIVITY ASSOCIATED WITH THE FRONT. THE LATEST HRRR DOES SHOW INCREASED DEVELOPMENT ACROSS MIDDLE TENNESSEE THIS AFTERNOON, ALTHOUGH THE BULK OF THE ACTIVITY WILL HOLD OFF UNTIL AFTER 00Z. HAVE UPDATED THE PUBLIC FORECAST AND DROPPED AFTERNOON POP`S TO THE "LIKELY" CATEGORY ALL AREAS. PREV DISCUSSION... /ISSUED 940 AM CDT MON APR 14 2014/ MESOSCALE UPDATE...MOST OF THE EARLIER SHOWERS HAVE EXITED MIDDLE TENNESSEE, WITH A DRY WEDGE NOW BUILDING IN THAT WILL KEEP US ESSENTIALLY RAIN-FREE FOR THE NEXT FEW HOURS. THE 14Z LAPS SOUNDING FOR BNA SHOWS VERY LITTLE INSTABILITY IN PLACE, WITH A CAPPING INVERSION ABOVE 900 MB. THE LATEST SURFACE MAP SHOWS A SURFACE COLD FRONT SITUATED JUST WEST OF PAH, WITH THE FRONT PUSHING THROUGH MIDDLE TENNESSEE DURING THE LATE AFTERNOON AND EVENING. MODEL SOUNDINGS DO SHOW THE AFOREMENTIONED CAP ERODING JUST AHEAD OF THE FRONT, WITH MUCH DEEPER INSTABILITY AND THUNDERSTORMS LIKELY DEVELOPING WITH THE FRONT. LIKEWISE, THE HRRR DOES SHOW MORE WIDESPREAD ACTIVITY DEVELOPING DURING THE AFTERNOON, SO THE CURRENT FORECAST APPEARS TO BE ON TARGET. SPC CONTINUES TO SHOW GENERAL THUNDERSTORMS FOR US, WITH A SLIGHT RISK AREA TO OUR SOUTH. PREV DISCUSSION... /ISSUED 710 AM CDT MON APR 14 2014/ UPDATE... PER CURRENT REGIONAL RADAR MOSAIC IMAGERY AND SHORT RANGE MODELS... LOOKS LIKE MAIN SWATH OF SHWRS/SCT TSTMS WILL MOVE E OF MID STATE OVER THE NEXT COUPLE OF HOURS...WITH GENERALLY A BREAK IN SHWRS EXPECTED UNTIL LATER THIS AFTERNOON. UPDATED THE SUITE OF FORECAST PRODUCTS TO MENTION A CHANCE OF SHWRS BEHIND MAIN BAND JUST IN CASE OF SOME DEVELOPMENT BEFORE THEN. PREV DISCUSSION.../ISSUED 641 AM CDT MON APR 14 2014/ AVIATION 12Z DISCUSSION... FRONTAL BOUNDARY TO MOVE ACROSS THE AREA TODAY. REDEVELOPMENT OF SHOWER AND TSTM ACTIVITY IS POSSIBLE THIS AFTERNOON. TONIGHT...UPPER LEVEL ENERGY WILL COME INTO PLAY WITHIN THE COLD SECTOR BEHIND THE FROPA. THIS WILL RESULT IN A CONTINUATION OF ELEVATED WIND SPEEDS...SHOWER CONDITIONS AND LOW CIGS. PREV DISCUSSION... /ISSUED 331 AM CDT MON APR 14 2014/ DISCUSSION... FORECAST REASONING WILL LEAN TOWARD A CONSENSUS MODEL SOLUTION COMPROMISE FOR THE FORECAST PERIOD UNLESS OTHERWISE NOTED. FORECAST QUANDARIES...CONVECTION STRENGTH TODAY...WINTRY MIX POTENTIAL MAINLY NW PORTIONS OF MID STATE LATE TONIGHT...WIND ADVISORY TODAY THRU TUE/FREEZE WATCH POTENTIAL WED MORNING... AND TEMPS. A LOT OF QUANDARIES FOR THIS FORECAST PERIOD. STARTING OFF... EXPECTING THIS INITIAL ROUND OF SHWRS/TSTMS TO MOVE THRU THE MID STATE THRU THE REMAINDER OF THE EARLY MORNING HRS...WITH ADDITIONAL REDEVELOPMENT EXPECTED AT LEAST BY THIS AFTERNOON AS SFC FRONT APPROACHES CKV AROUND 18Z AND MOVES TO JUST EAST OF NASHVILLE BY 00Z. SOME STRONG TSTMS WILL CONTINUE TO BE POSSIBLE TODAY JUST AHEAD OF THE FRONTAL PASSAGE AND ACROSS SRN PORTIONS OF THE MID STATE WHERE INSTABILITY AND FORCING WILL BE THE GREATEST. WILL GO CLOSE TO MOS VALUES FOR TEMPS TODAY WITH HIGHS IN THE UPPER 60S TO LOWER 70S. FRONT SHOULD PUSH E OF PLATEAU BY 15/06Z...WITH SOME LINGERING MOISTURE BEHIND FRONTAL PASSAGE AHEAD OF THE UPPER LEVEL TROUGH. THERE IS SOME POTENTIAL FOR A WINTRY MIX LATE ACROSS NW PORTIONS OF THE MID STATE AS COLDER AIR WORKS IN...WITH TEMPS IN THE MID 30S ACROSS THIS PORTION OF THE MID STATE...BUT UPPER 30S TO LOWER 40S ELSEWHERE...BUT WITH MOISTURE PULLING OUT OF THIS REGION RATHER QUICKLY AFTER 15/06Z...DO NOT FEEL AT THIS TIME CONFIDENT ENOUGH TO MENTION...AND BELIEVE ANOTHER SET OF MODEL RUNS IS NEEDED FOR FURTHER CLARIFICATION. EXPECTING TEMPS TO MAINLY BE IN THE UPPER 40S ON TUE WITH BREEZY CONDITIONS CONTINUING. AS RIDGING INFLUENCES BECOME EVEN MORE ENHANCED ACROSS THE MID STATE ON TUE NIGHT...SKIES CLEAR...AND WINDS BECOME LIGHT...TEMPS SHOULD DROP INTO THE MID TO UPPER 20S. THUS...WITH THE ABOVE IN MIND...AND WITH THE SURFACE PRESSURE GRADIENT CONTINUING TO BE STRONG THROUGH 15/00Z...AND INCREASING EVEN MORE AFTER FRONTAL PASSAGE FROM 15/00Z-15/18Z...AND THEN SLIGHTLY WEAKENING FROM 15/18Z-16/00Z...AND TO NOT CAUSE CONFUSION BETWEEN SPS PRODUCT THAT NEEDS TO BE UPDATED...WILL BE ISSUING A WIND ADVISORY THRU 16/00Z WITH BREEZY CONDITIONS WITH SUSTAINED SOUTHERLY WINDS OF 15 TO 25 MPH WITH GUSTS TO 35 MPH POSSIBLE THRU 15/00Z...SUSTAINED NORTH WINDS OF 20 TO 30 MPH WITH GUSTS 40-45 MPH 15/00Z-15/18Z...AND GUSTS BACK TO 35 MPH BETWEEN 15/18Z-16/00Z WITH SUSTAINED WINDS OF 15 TO 25 MPH. THUS...AGAIN...WITH THE ABOVE IN MIND ALSO...AND WITH EXPECTED TEMPS MAINLY BELOW 27 DEGREES...A HARD FREEZE IS BECOMING MORE AND MORE LIKELY TO OCCUR BY WED MORNING...AND THUS WILL BE ISSUING A FREEZE WATCH FROM MIDNIGHT UNTIL 9 AM CDT ON WED MORNING. WILL BE GOING CLOSE TO PREVIOUS FORECAST REASONING REMAINDER OF WED THRU THE WEEKEND WITH THE NEXT FRONTAL SYSTEM TO MOVE INTO THE MID STATE FRI INTO FRI NIGHT...WITH TEMPS AGAIN APPROACHING SEASONABLE NORMAL VALUES BY WEEKENDS END. && .OHX WATCHES/WARNINGS/ADVISORIES... FREEZE WATCH FROM LATE TUESDAY NIGHT THROUGH WEDNESDAY MORNING FOR TNZ005>011-023>034-056>066-075-077>080-093>095. WIND ADVISORY UNTIL 7 PM CDT TUESDAY FOR TNZ005>011-023>034- 056>066-075-077>080-093>095. && $$ ROSE
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1128 AM CDT MON APR 14 2014 .UPDATE...COLD FRONT HAS NOSED INTO WESTERN KY, ALTHOUGH RADAR MOSAIC CONTINUES TO SHOW LITTLE ACTIVITY ASSOCIATED WITH THE FRONT. THE LATEST HRRR DOES SHOW INCREASED DEVELOPMENT ACROSS MIDDLE TENNESSEE THIS AFTERNOON, ALTHOUGH THE BULK OF THE ACTIVITY WILL HOLD OFF UNTIL AFTER 00Z. HAVE UPDATED THE PUBLIC FORECAST AND DROPPED AFTERNOON POP`S TO THE "LIKELY" CATEGORY ALL AREAS. && .PREV DISCUSSION... /ISSUED 940 AM CDT MON APR 14 2014/ MESOSCALE UPDATE...MOST OF THE EARLIER SHOWERS HAVE EXITED MIDDLE TENNESSEE, WITH A DRY WEDGE NOW BUILDING IN THAT WILL KEEP US ESSENTIALLY RAIN-FREE FOR THE NEXT FEW HOURS. THE 14Z LAPS SOUNDING FOR BNA SHOWS VERY LITTLE INSTABILITY IN PLACE, WITH A CAPPING INVERSION ABOVE 900 MB. THE LATEST SURFACE MAP SHOWS A SURFACE COLD FRONT SITUATED JUST WEST OF PAH, WITH THE FRONT PUSHING THROUGH MIDDLE TENNESSEE DURING THE LATE AFTERNOON AND EVENING. MODEL SOUNDINGS DO SHOW THE AFOREMENTIONED CAP ERODING JUST AHEAD OF THE FRONT, WITH MUCH DEEPER INSTABILITY AND THUNDERSTORMS LIKELY DEVELOPING WITH THE FRONT. LIKEWISE, THE HRRR DOES SHOW MORE WIDESPREAD ACTIVITY DEVELOPING DURING THE AFTERNOON, SO THE CURRENT FORECAST APPEARS TO BE ON TARGET. SPC CONTINUES TO SHOW GENERAL THUNDERSTORMS FOR US, WITH A SLIGHT RISK AREA TO OUR SOUTH. PREV DISCUSSION... /ISSUED 710 AM CDT MON APR 14 2014/ UPDATE... PER CURRENT REGIONAL RADAR MOSAIC IMAGERY AND SHORT RANGE MODELS... LOOKS LIKE MAIN SWATH OF SHWRS/SCT TSTMS WILL MOVE E OF MID STATE OVER THE NEXT COUPLE OF HOURS...WITH GENERALLY A BREAK IN SHWRS EXPECTED UNTIL LATER THIS AFTERNOON. UPDATED THE SUITE OF FORECAST PRODUCTS TO MENTION A CHANCE OF SHWRS BEHIND MAIN BAND JUST IN CASE OF SOME DEVELOPMENT BEFORE THEN. PREV DISCUSSION.../ISSUED 641 AM CDT MON APR 14 2014/ AVIATION 12Z DISCUSSION... FRONTAL BOUNDARY TO MOVE ACROSS THE AREA TODAY. REDEVELOPMENT OF SHOWER AND TSTM ACTIVITY IS POSSIBLE THIS AFTERNOON. TONIGHT...UPPER LEVEL ENERGY WILL COME INTO PLAY WITHIN THE COLD SECTOR BEHIND THE FROPA. THIS WILL RESULT IN A CONTINUATION OF ELEVATED WIND SPEEDS...SHOWER CONDITIONS AND LOW CIGS. PREV DISCUSSION... /ISSUED 331 AM CDT MON APR 14 2014/ DISCUSSION... FORECAST REASONING WILL LEAN TOWARD A CONSENSUS MODEL SOLUTION COMPROMISE FOR THE FORECAST PERIOD UNLESS OTHERWISE NOTED. FORECAST QUANDARIES...CONVECTION STRENGTH TODAY...WINTRY MIX POTENTIAL MAINLY NW PORTIONS OF MID STATE LATE TONIGHT...WIND ADVISORY TODAY THRU TUE/FREEZE WATCH POTENTIAL WED MORNING... AND TEMPS. A LOT OF QUANDARIES FOR THIS FORECAST PERIOD. STARTING OFF... EXPECTING THIS INITIAL ROUND OF SHWRS/TSTMS TO MOVE THRU THE MID STATE THRU THE REMAINDER OF THE EARLY MORNING HRS...WITH ADDITIONAL REDEVELOPMENT EXPECTED AT LEAST BY THIS AFTERNOON AS SFC FRONT APPROACHES CKV AROUND 18Z AND MOVES TO JUST EAST OF NASHVILLE BY 00Z. SOME STRONG TSTMS WILL CONTINUE TO BE POSSIBLE TODAY JUST AHEAD OF THE FRONTAL PASSAGE AND ACROSS SRN PORTIONS OF THE MID STATE WHERE INSTABILITY AND FORCING WILL BE THE GREATEST. WILL GO CLOSE TO MOS VALUES FOR TEMPS TODAY WITH HIGHS IN THE UPPER 60S TO LOWER 70S. FRONT SHOULD PUSH E OF PLATEAU BY 15/06Z...WITH SOME LINGERING MOISTURE BEHIND FRONTAL PASSAGE AHEAD OF THE UPPER LEVEL TROUGH. THERE IS SOME POTENTIAL FOR A WINTRY MIX LATE ACROSS NW PORTIONS OF THE MID STATE AS COLDER AIR WORKS IN...WITH TEMPS IN THE MID 30S ACROSS THIS PORTION OF THE MID STATE...BUT UPPER 30S TO LOWER 40S ELSEWHERE...BUT WITH MOISTURE PULLING OUT OF THIS REGION RATHER QUICKLY AFTER 15/06Z...DO NOT FEEL AT THIS TIME CONFIDENT ENOUGH TO MENTION...AND BELIEVE ANOTHER SET OF MODEL RUNS IS NEEDED FOR FURTHER CLARIFICATION. EXPECTING TEMPS TO MAINLY BE IN THE UPPER 40S ON TUE WITH BREEZY CONDITIONS CONTINUING. AS RIDGING INFLUENCES BECOME EVEN MORE ENHANCED ACROSS THE MID STATE ON TUE NIGHT...SKIES CLEAR...AND WINDS BECOME LIGHT...TEMPS SHOULD DROP INTO THE MID TO UPPER 20S. THUS...WITH THE ABOVE IN MIND...AND WITH THE SURFACE PRESSURE GRADIENT CONTINUING TO BE STRONG THROUGH 15/00Z...AND INCREASING EVEN MORE AFTER FRONTAL PASSAGE FROM 15/00Z-15/18Z...AND THEN SLIGHTLY WEAKENING FROM 15/18Z-16/00Z...AND TO NOT CAUSE CONFUSION BETWEEN SPS PRODUCT THAT NEEDS TO BE UPDATED...WILL BE ISSUING A WIND ADVISORY THRU 16/00Z WITH BREEZY CONDITIONS WITH SUSTAINED SOUTHERLY WINDS OF 15 TO 25 MPH WITH GUSTS TO 35 MPH POSSIBLE THRU 15/00Z...SUSTAINED NORTH WINDS OF 20 TO 30 MPH WITH GUSTS 40-45 MPH 15/00Z-15/18Z...AND GUSTS BACK TO 35 MPH BETWEEN 15/18Z-16/00Z WITH SUSTAINED WINDS OF 15 TO 25 MPH. THUS...AGAIN...WITH THE ABOVE IN MIND ALSO...AND WITH EXPECTED TEMPS MAINLY BELOW 27 DEGREES...A HARD FREEZE IS BECOMING MORE AND MORE LIKELY TO OCCUR BY WED MORNING...AND THUS WILL BE ISSUING A FREEZE WATCH FROM MIDNIGHT UNTIL 9 AM CDT ON WED MORNING. WILL BE GOING CLOSE TO PREVIOUS FORECAST REASONING REMAINDER OF WED THRU THE WEEKEND WITH THE NEXT FRONTAL SYSTEM TO MOVE INTO THE MID STATE FRI INTO FRI NIGHT...WITH TEMPS AGAIN APPROACHING SEASONABLE NORMAL VALUES BY WEEKENDS END. && .OHX WATCHES/WARNINGS/ADVISORIES... FREEZE WATCH FROM LATE TUESDAY NIGHT THROUGH WEDNESDAY MORNING FOR TNZ005>011-023>034-056>066-075-077>080-093>095. WIND ADVISORY UNTIL 7 PM CDT TUESDAY FOR TNZ005>011-023>034- 056>066-075-077>080-093>095. && $$ ROSE
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
940 AM CDT MON APR 14 2014 .MESOSCALE UPDATE...MOST OF THE EARLIER SHOWERS HAVE EXITED MIDDLE TENNESSEE, WITH A DRY WEDGE NOW BUILDING IN THAT WILL KEEP US ESSENTIALLY RAIN-FREE FOR THE NEXT FEW HOURS. THE 14Z LAPS SOUNDING FOR BNA SHOWS VERY LITTLE INSTABILITY IN PLACE, WITH A CAPPING INVERSION ABOVE 900 MB. THE LATEST SURFACE MAP SHOWS A SURFACE COLD FRONT SITUATED JUST WEST OF PAH, WITH THE FRONT PUSHING THROUGH MIDDLE TENNESSEE DURING THE LATE AFTERNOON AND EVENING. MODEL SOUNDINGS DO SHOW THE AFOREMENTIONED CAP ERODING JUST AHEAD OF THE FRONT, WITH MUCH DEEPER INSTABILITY AND THUNDERSTORMS LIKELY DEVELOPING WITH THE FRONT. LIKEWISE, THE HRRR DOES SHOW MORE WIDESPREAD ACTIVITY DEVELOPING DURING THE AFTERNOON, SO THE CURRENT FORECAST APPEARS TO BE ON TARGET. SPC CONTINUES TO SHOW GENERAL THUNDERSTORMS FOR US, WITH A SLIGHT RISK AREA TO OUR SOUTH. && .PREV DISCUSSION... /ISSUED 710 AM CDT MON APR 14 2014/ UPDATE... PER CURRENT REGIONAL RADAR MOSAIC IMAGERY AND SHORT RANGE MODELS... LOOKS LIKE MAIN SWATH OF SHWRS/SCT TSTMS WILL MOVE E OF MID STATE OVER THE NEXT COUPLE OF HOURS...WITH GENERALLY A BREAK IN SHWRS EXPECTED UNTIL LATER THIS AFTERNOON. UPDATED THE SUITE OF FORECAST PRODUCTS TO MENTION A CHANCE OF SHWRS BEHIND MAIN BAND JUST IN CASE OF SOME DEVELOPMENT BEFORE THEN. PREV DISCUSSION.../ISSUED 641 AM CDT MON APR 14 2014/ AVIATION 12Z DISCUSSION... FRONTAL BOUNDARY TO MOVE ACROSS THE AREA TODAY. REDEVELOPMENT OF SHOWER AND TSTM ACTIVITY IS POSSIBLE THIS AFTERNOON. TONIGHT...UPPER LEVEL ENERGY WILL COME INTO PLAY WITHIN THE COLD SECTOR BEHIND THE FROPA. THIS WILL RESULT IN A CONTINUATION OF ELEVATED WIND SPEEDS...SHOWER CONDITIONS AND LOW CIGS. PREV DISCUSSION... /ISSUED 331 AM CDT MON APR 14 2014/ DISCUSSION... FORECAST REASONING WILL LEAN TOWARD A CONSENSUS MODEL SOLUTION COMPROMISE FOR THE FORECAST PERIOD UNLESS OTHERWISE NOTED. FORECAST QUANDARIES...CONVECTION STRENGTH TODAY...WINTRY MIX POTENTIAL MAINLY NW PORTIONS OF MID STATE LATE TONIGHT...WIND ADVISORY TODAY THRU TUE/FREEZE WATCH POTENTIAL WED MORNING... AND TEMPS. A LOT OF QUANDARIES FOR THIS FORECAST PERIOD. STARTING OFF... EXPECTING THIS INITIAL ROUND OF SHWRS/TSTMS TO MOVE THRU THE MID STATE THRU THE REMAINDER OF THE EARLY MORNING HRS...WITH ADDITIONAL REDEVELOPMENT EXPECTED AT LEAST BY THIS AFTERNOON AS SFC FRONT APPROACHES CKV AROUND 18Z AND MOVES TO JUST EAST OF NASHVILLE BY 00Z. SOME STRONG TSTMS WILL CONTINUE TO BE POSSIBLE TODAY JUST AHEAD OF THE FRONTAL PASSAGE AND ACROSS SRN PORTIONS OF THE MID STATE WHERE INSTABILITY AND FORCING WILL BE THE GREATEST. WILL GO CLOSE TO MOS VALUES FOR TEMPS TODAY WITH HIGHS IN THE UPPER 60S TO LOWER 70S. FRONT SHOULD PUSH E OF PLATEAU BY 15/06Z...WITH SOME LINGERING MOISTURE BEHIND FRONTAL PASSAGE AHEAD OF THE UPPER LEVEL TROUGH. THERE IS SOME POTENTIAL FOR A WINTRY MIX LATE ACROSS NW PORTIONS OF THE MID STATE AS COLDER AIR WORKS IN...WITH TEMPS IN THE MID 30S ACROSS THIS PORTION OF THE MID STATE...BUT UPPER 30S TO LOWER 40S ELSEWHERE...BUT WITH MOISTURE PULLING OUT OF THIS REGION RATHER QUICKLY AFTER 15/06Z...DO NOT FEEL AT THIS TIME CONFIDENT ENOUGH TO MENTION...AND BELIEVE ANOTHER SET OF MODEL RUNS IS NEEDED FOR FURTHER CLARIFICATION. EXPECTING TEMPS TO MAINLY BE IN THE UPPER 40S ON TUE WITH BREEZY CONDITIONS CONTINUING. AS RIDGING INFLUENCES BECOME EVEN MORE ENHANCED ACROSS THE MID STATE ON TUE NIGHT...SKIES CLEAR...AND WINDS BECOME LIGHT...TEMPS SHOULD DROP INTO THE MID TO UPPER 20S. THUS...WITH THE ABOVE IN MIND...AND WITH THE SURFACE PRESSURE GRADIENT CONTINUING TO BE STRONG THROUGH 15/00Z...AND INCREASING EVEN MORE AFTER FRONTAL PASSAGE FROM 15/00Z-15/18Z...AND THEN SLIGHTLY WEAKENING FROM 15/18Z-16/00Z...AND TO NOT CAUSE CONFUSION BETWEEN SPS PRODUCT THAT NEEDS TO BE UPDATED...WILL BE ISSUING A WIND ADVISORY THRU 16/00Z WITH BREEZY CONDITIONS WITH SUSTAINED SOUTHERLY WINDS OF 15 TO 25 MPH WITH GUSTS TO 35 MPH POSSIBLE THRU 15/00Z...SUSTAINED NORTH WINDS OF 20 TO 30 MPH WITH GUSTS 40-45 MPH 15/00Z-15/18Z...AND GUSTS BACK TO 35 MPH BETWEEN 15/18Z-16/00Z WITH SUSTAINED WINDS OF 15 TO 25 MPH. THUS...AGAIN...WITH THE ABOVE IN MIND ALSO...AND WITH EXPECTED TEMPS MAINLY BELOW 27 DEGREES...A HARD FREEZE IS BECOMING MORE AND MORE LIKELY TO OCCUR BY WED MORNING...AND THUS WILL BE ISSUING A FREEZE WATCH FROM MIDNIGHT UNTIL 9 AM CDT ON WED MORNING. WILL BE GOING CLOSE TO PREVIOUS FORECAST REASONING REMAINDER OF WED THRU THE WEEKEND WITH THE NEXT FRONTAL SYSTEM TO MOVE INTO THE MID STATE FRI INTO FRI NIGHT...WITH TEMPS AGAIN APPROACHING SEASONABLE NORMAL VALUES BY WEEKENDS END. && .OHX WATCHES/WARNINGS/ADVISORIES... FREEZE WATCH FROM LATE TUESDAY NIGHT THROUGH WEDNESDAY MORNING FOR TNZ005>011-023>034-056>066-075-077>080-093>095. WIND ADVISORY UNTIL 7 PM CDT TUESDAY FOR TNZ005>011-023>034- 056>066-075-077>080-093>095. && $$ ROSE
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1213 AM CDT MON APR 14 2014 .UPDATE...FOR 06Z AVIATION FORECASTS && .AVIATION... SHOWERS AND TSTMS HAVE BEEN RACING NORTHEASTWARD TOWARD MIDDLE TN THIS EVENING. A FEW LIGHT SHOWERS CROSSED FROM WEST TN INTO MIDDLE TN AFTER 05Z WITH MORE POISED TO FOLLOW. SHOWERS AND ISOLATED TSTMS WERE ALREADY BEGINNING TO IMPACT KCKV AREA AT 05Z...AND WILL START IMPACTING KBNA AREA BY 06Z. PRECIP WILL SPREAD QUICKLY FROM WEST TO EAST...AND SHOULD APPROACH KCSV BY 10Z. GUSTY SOUTH WINDS WILL CONTINUE THE REST OF THE NIGHT WELL AHEAD OF THE ADVANCING COLD FRONT WHICH STRETCHED FROM SE OK TO EASTERN MO AT 05Z. FRONT IS PROGGED TO MOVE QUICKER THAN FORECAST EARLIER...AND MAY ARRIVE AT KCKV BEFORE 21Z...KBNA AFTER 21Z...AND KCSV AROUND THE END OF THIS FORECAST CYCLE. BEST CHANCES FOR SHOWERS/TSTMS WILL BE WITH THIS OVERNIGHT/EARLY MORNING ACTIVITY BUT CHANCES WILL CONTINUE UNTIL A FEW HOURS AFTER THE FRONT PASSES. && .PREV DISCUSSION... /ISSUED 1112 PM CDT SUN APR 13 2014/ UPDATE... THE APPROACHING SQUALL LINE IS TAKING ON A MORE ORGANIZED LINEAR STRUCTURE WITH EMBEDDED BOWING SEGMENTS WITHIN THE SOUTHERN PORTION OF THE LINE. WITH PLENTY OF MID LEVEL DRY AIR IN PLACE...THE STRONG TO SEVERE WIND THREAT WILL CONTINUE. ALTHOUGH DEVELOPMENT IS LESS ORGANIZED SOUTH OF THE I40 CORRIDOR. THEREFORE...THINK THIS WIND THREAT WILL STAY MOSTLY NORTH OF THE I40 CORRIDOR AND WEST OF THE I65 CORRIDOR MAINLY IMPACTING OUR NW COUNTIES. STORM TOPS ARE NOT EXCEEDING 25KFT SO HAIL DOES NOT APPEAR TO BE A THREAT...HOWEVER THIS LINE HAS PRODUCED EMBEDDED ROTATIONS WITH ALL THE OF THE AVAILABLE SHEARING PRESENT. STILL OVER 50 KT OF 0-6 KM BULK SHEAR IN WESTERN TENNESSEE AND WHILE THOSE SHEAR VALUES DECREASE ENTERING MIDDLE TN...STILL WILL NEED TO KEEP AN EYE ON EMBEDDED ROTATIONS THAT MAY RESULT DUE TO BOWING IN THE LINE. LCLS ARE STILL VERY HIGH ACCORDING TO LATEST RUC SOUNDINGS SO THAT DOES NOT BODE WELL FOR TORNADIC CHANCES. PREV DISCUSSION... /ISSUED 805 PM CDT SUN APR 13 2014/ UPDATE... 500 MB JET STREAK IS BEGINNING TO ENTER THE MS RIVER VALLEY WHICH IS LARGELY FUELING THE AREA OF SHOWERS AND THUNDERSTORMS IN THAT REGION. THIS WILL CONTINUE TO PROGRESS EASTWARD OVER THE NEXT FEW HOURS. MID LEVEL DRY AIR...AS SHOWN IN THE RUC TIME HEIGHT AND THE 00Z ROAB...SHOULD KEEP THE SHOWERS FROM ENTERING THE MID STATE BEFORE 06Z. THEREFORE...OPTED TO REMOVE POP CHANCES PRIOR TO 03Z AND ONLY LEFT WESTERN AREAS IN SLGT CHC CATEGORY UNTIL 06Z. ALL SHORT RANGE MODELS KEEP ANY QPF WEST OF THE TN RIVER UNTIL THAT POINT. POP CHANCES RISE AFTER 06Z. AS FOR TONIGHTS STORM SEVERITY POTENTIAL...CONVECTIVELY...THE PARAMETERS ARE NOT IMPRESSIVE WITH CIN OVERCOMING CAPE ON THE RUC FORECAST SOUNDINGS SHORTLY AFTER MIDNIGHT. HOWEVER...DYNAMICALLY SPEAKING...A STOUT 850 MB LLJ AND 500 MB JET MAX SHOULD KEEP THUNDER PLENTIFUL. GUSTY WIND POTENTIAL WILL BE STILL BE MODERATE WITH THE INITIAL STORMS BETWEEN 03Z AND 09Z IN THE WEST DUE TO MID LEVEL DRY AIR AND INVERTED V SOUNDINGS OUT WEST. PLUS...SHEAR VALUES WOULD HINT AT THE POSSIBILITY OF SOME BOWING SEGMENTS WITH THE MORE INTENSE STORMS WITHIN THE LINE. HOWEVER WIND POTENTIAL SHOULD DROP OFF SUBSTANTIALLY SOON AFTER STORM ONSET AS THE LOW LEVEL ATMOSPHERE MOISTENS WITH THE HEALTHY QPF WE SHOULD RECEIVE. PREV DISCUSSION... /ISSUED 656 PM CDT SUN APR 13 2014/ UPDATE...FOR 00Z AVIATION FORECAST AVIATION... EXTENSIVE HIGH CLOUDS AND GUSTY WINDS WILL CONTINUE ACROSS MID TN THIS EVENING AS UPPER DISTURBANCE MOVES TOWARD MS VALLEY. CIGS WILL BEGIN TO LOWER AND RAIN CHANCES WILL GO UP AS MOISTURE CONTINUES TO INCEASE LATER TONIGHT INTO MONDAY. BEST CHANCES FOR SHOWERS AND ISOLATED TSTMS SHOULD BE IN A 2 TO 4 HOUR WINDOW THAT STARTS AT 08Z AT KCKV...AT 09Z AT KBNA AND AFTER 12Z AT KCSV. CONTINUED CHANCES FOR SHOWERS AND ISOLATED TSTMS MONDAY AFTERNOON AS COLD FRONT MOVES SLOWLY INTO THE REGION. FRONT COULD MAKE IT TO KCKV CLOSE TO 00Z TUE...BUT NOT UNTIL AFTER 00Z TUE AT KBNA/KCSV. PREV DISCUSSION... /ISSUED 222 PM CDT SUN APR 13 2014/ DISCUSSION... CLOUDS WILL INCREASE THROUGH THE AFTERNOON AS SURFACE RIDGE BEGINS TO WEAKEN OVER THE SOUTHEAST AS CENTRAL AND SOUTHERN PLAINS LOW CONTINUES TO DEEPEN. GRADIENT BETWEEN THE TWO SYSTEMS IS TIGHT ENOUGH TO KEEP WINDS UP TONIGHT AND DURING THE DAY ON MONDAY. SHOWERS AND A FEW THUNDERSTORMS WILL WORK INTO FAR WESTERN MIDDLE TENNESSEE AROUND MIDNIGHT AND TRANSLATE EASTWARD OVERNIGHT. MODELS IN AGREEMENT IN COLD FRONT ALONG THE MISSISSIPPI RIVER BY 12Z MONDAY WITH SHOWERS AND STORMS ACROSS THE MID STATE. A FEW STORMS COULD BE STRONG TO MARGINIALLY SEVERE DURING THE DAY MONDAY. SURFACE WINDS WILL BE GUSTY. FROPA AT CLARKSVILLE MONDAY AROUND 18Z...AND AROUND 23Z AT NASHVILLE AND TOWARDS MIDNIGHT MONDAY NIGHT ALONG THE PLATEAU. WINDS PICK UP IN SPEED OUT OF THE NORTHWEST AND GUSTY MONDAY NIGHT...COULD SEE GUSTS TO 30 TO 35 MPH. SHARPLY COLDER MONDAY NIGHT WITH LOWS DOWN IN THE MID AND UPPER 30S BUT NO FROST DUE TO WIND AND CLOUDS. BLUSTERY DAY ON TUESDAY WITH HIGHS MOSTLY IN THE UPPER 40S. (THE LOWEST DAILY HIGH AT NASHVILLE FOR APRIL 15TH (TUESDAY) IS 46 DEGREES SET BACK IN 1903). FREEZE LIKELY TUESDAY NIGHT WITH LOWS RANGING FROM 28-32 DEGREES. HIGHS WEDNESDAY THROUGH FRIDAY IN THE 60S WITH DRY WEATHER UNTIL FRIDAY WHEN ANOTHER FRONTAL SYSTEM APPROACHES FROM THE WEST BRINGING A CHANCE FOR SHOWERS AND A FEW THUNDERSTORMS. PLEASANT WEATHER OVER THE WEEKEND WITH HIGHS AROUND 70. CLIMATE...FREEZE LOOKS LIKELY TUESDAY NIGHT/WEDNESDAY MORNING WITH LOWS RANGING FROM 28 TO 32 DEGREES. SENSITIVE PLANTS WILL NEED TO BE PROTECTED. THE RECORD LOW AT NASHVILLE FOR APRIL 16TH IS 28 DEGREES SET BACK IN 1988. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 49
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1112 PM CDT SUN APR 13 2014 .UPDATE... THE APPROACHING SQUALL LINE IS TAKING ON A MORE ORGANIZED LINEAR STRUCTURE WITH EMBEDDED BOWING SEGMENTS WITHIN THE SOUTHERN PORTION OF THE LINE. WITH PLENTY OF MID LEVEL DRY AIR IN PLACE...THE STRONG TO SEVERE WIND THREAT WILL CONTINUE. ALTHOUGH DEVELOPMENT IS LESS ORGANIZED SOUTH OF THE I40 CORRIDOR. THEREFORE...THINK THIS WIND THREAT WILL STAY MOSTLY NORTH OF THE I40 CORRIDOR AND WEST OF THE I65 CORRIDOR MAINLY IMPACTING OUR NW COUNTIES. STORM TOPS ARE NOT EXCEEDING 25KFT SO HAIL DOES NOT APPEAR TO BE A THREAT...HOWEVER THIS LINE HAS PRODUCED EMBEDDED ROTATIONS WITH ALL THE OF THE AVAILABLE SHEARING PRESENT. STILL OVER 50 KT OF 0-6 KM BULK SHEAR IN WESTERN TENNESSEE AND WHILE THOSE SHEAR VALUES DECREASE ENTERING MIDDLE TN...STILL WILL NEED TO KEEP AN EYE ON EMBEDDED ROTATIONS THAT MAY RESULT DUE TO BOWING IN THE LINE. LCLS ARE STILL VERY HIGH ACCORDING TO LATEST RUC SOUNDINGS SO THAT DOES NOT BODE WELL FOR TORNADIC CHANCES. && .PREV DISCUSSION... /ISSUED 805 PM CDT SUN APR 13 2014/ UPDATE... 500 MB JET STREAK IS BEGINNING TO ENTER THE MS RIVER VALLEY WHICH IS LARGELY FUELING THE AREA OF SHOWERS AND THUNDERSTORMS IN THAT REGION. THIS WILL CONTINUE TO PROGRESS EASTWARD OVER THE NEXT FEW HOURS. MID LEVEL DRY AIR...AS SHOWN IN THE RUC TIME HEIGHT AND THE 00Z ROAB...SHOULD KEEP THE SHOWERS FROM ENTERING THE MID STATE BEFORE 06Z. THEREFORE...OPTED TO REMOVE POP CHANCES PRIOR TO 03Z AND ONLY LEFT WESTERN AREAS IN SLGT CHC CATEGORY UNTIL 06Z. ALL SHORT RANGE MODELS KEEP ANY QPF WEST OF THE TN RIVER UNTIL THAT POINT. POP CHANCES RISE AFTER 06Z. AS FOR TONIGHTS STORM SEVERITY POTENTIAL...CONVECTIVELY...THE PARAMETERS ARE NOT IMPRESSIVE WITH CIN OVERCOMING CAPE ON THE RUC FORECAST SOUNDINGS SHORTLY AFTER MIDNIGHT. HOWEVER...DYNAMICALLY SPEAKING...A STOUT 850 MB LLJ AND 500 MB JET MAX SHOULD KEEP THUNDER PLENTIFUL. GUSTY WIND POTENTIAL WILL BE STILL BE MODERATE WITH THE INITIAL STORMS BETWEEN 03Z AND 09Z IN THE WEST DUE TO MID LEVEL DRY AIR AND INVERTED V SOUNDINGS OUT WEST. PLUS...SHEAR VALUES WOULD HINT AT THE POSSIBILITY OF SOME BOWING SEGMENTS WITH THE MORE INTENSE STORMS WITHIN THE LINE. HOWEVER WIND POTENTIAL SHOULD DROP OFF SUBSTANTIALLY SOON AFTER STORM ONSET AS THE LOW LEVEL ATMOSPHERE MOISTENS WITH THE HEALTHY QPF WE SHOULD RECEIVE. PREV DISCUSSION... /ISSUED 656 PM CDT SUN APR 13 2014/ UPDATE...FOR 00Z AVIATION FORECAST AVIATION... EXTENSIVE HIGH CLOUDS AND GUSTY WINDS WILL CONTINUE ACROSS MID TN THIS EVENING AS UPPER DISTURBANCE MOVES TOWARD MS VALLEY. CIGS WILL BEGIN TO LOWER AND RAIN CHANCES WILL GO UP AS MOISTURE CONTINUES TO INCEASE LATER TONIGHT INTO MONDAY. BEST CHANCES FOR SHOWERS AND ISOLATED TSTMS SHOULD BE IN A 2 TO 4 HOUR WINDOW THAT STARTS AT 08Z AT KCKV...AT 09Z AT KBNA AND AFTER 12Z AT KCSV. CONTINUED CHANCES FOR SHOWERS AND ISOLATED TSTMS MONDAY AFTERNOON AS COLD FRONT MOVES SLOWLY INTO THE REGION. FRONT COULD MAKE IT TO KCKV CLOSE TO 00Z TUE...BUT NOT UNTIL AFTER 00Z TUE AT KBNA/KCSV. PREV DISCUSSION... /ISSUED 222 PM CDT SUN APR 13 2014/ DISCUSSION... CLOUDS WILL INCREASE THROUGH THE AFTERNOON AS SURFACE RIDGE BEGINS TO WEAKEN OVER THE SOUTHEAST AS CENTRAL AND SOUTHERN PLAINS LOW CONTINUES TO DEEPEN. GRADIENT BETWEEN THE TWO SYSTEMS IS TIGHT ENOUGH TO KEEP WINDS UP TONIGHT AND DURING THE DAY ON MONDAY. SHOWERS AND A FEW THUNDERSTORMS WILL WORK INTO FAR WESTERN MIDDLE TENNESSEE AROUND MIDNIGHT AND TRANSLATE EASTWARD OVERNIGHT. MODELS IN AGREEMENT IN COLD FRONT ALONG THE MISSISSIPPI RIVER BY 12Z MONDAY WITH SHOWERS AND STORMS ACROSS THE MID STATE. A FEW STORMS COULD BE STRONG TO MARGINIALLY SEVERE DURING THE DAY MONDAY. SURFACE WINDS WILL BE GUSTY. FROPA AT CLARKSVILLE MONDAY AROUND 18Z...AND AROUND 23Z AT NASHVILLE AND TOWARDS MIDNIGHT MONDAY NIGHT ALONG THE PLATEAU. WINDS PICK UP IN SPEED OUT OF THE NORTHWEST AND GUSTY MONDAY NIGHT...COULD SEE GUSTS TO 30 TO 35 MPH. SHARPLY COLDER MONDAY NIGHT WITH LOWS DOWN IN THE MID AND UPPER 30S BUT NO FROST DUE TO WIND AND CLOUDS. BLUSTERY DAY ON TUESDAY WITH HIGHS MOSTLY IN THE UPPER 40S. (THE LOWEST DAILY HIGH AT NASHVILLE FOR APRIL 15TH (TUESDAY) IS 46 DEGREES SET BACK IN 1903). FREEZE LIKELY TUESDAY NIGHT WITH LOWS RANGING FROM 28-32 DEGREES. HIGHS WEDNESDAY THROUGH FRIDAY IN THE 60S WITH DRY WEATHER UNTIL FRIDAY WHEN ANOTHER FRONTAL SYSTEM APPROACHES FROM THE WEST BRINGING A CHANCE FOR SHOWERS AND A FEW THUNDERSTORMS. PLEASANT WEATHER OVER THE WEEKEND WITH HIGHS AROUND 70. CLIMATE...FREEZE LOOKS LIKELY TUESDAY NIGHT/WEDNESDAY MORNING WITH LOWS RANGING FROM 28 TO 32 DEGREES. SENSITIVE PLANTS WILL NEED TO BE PROTECTED. THE RECORD LOW AT NASHVILLE FOR APRIL 16TH IS 28 DEGREES SET BACK IN 1988. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ TB12
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
1149 AM CDT MON APR 14 2014 .AVIATION... CONCERNS...TIMING OF IMPROVEMENT FROM MVFR TO VFR CONDITIONS. ISOLATED THUNDERSTORMS POSSIBLE THROUGH 21Z IN THE WACO AREA. ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS ACROSS LOCATIONS SOUTHEAST OF A LAMPASAS TO WAXAHACHIE TO PARIS LINE. THESE SHOWERS AND THUNDERSTORMS WILL SHIFT EAST DURING THE AFTERNOON. HAVE LEFT VCSH IN THE WACO TAF THROUGH 20Z. OTHERWISE MVFR CEILINGS OF 2500-3000 FEET WILL IMPROVE TO VFR...3500-4000 FEET BETWEEN 19 AND 21Z AT THE TAF SITES. SKIES WILL CLEAR LATE AFTERNOON. GUSTY NORTHERLY WINDS AROUND 20 KNOTS WITH GUSTS TO AROUND 30 KNOTS WILL DECREASE TO 20 TO 25 KNOTS BY 23Z AND DOWN TO AROUND 15 KNOTS BY 02Z. NORTH WINDS WILL DECREASE TO AROUND 5 KNOTS BY 12Z. WINDS WILL BECOME WESTERLY BY 19Z TUESDAY AND SOUTHWEST BEFORE 00Z WEDNESDAY. 58 && .UPDATE... GRIDS HAVE BEEN UPDATED TO INCLUDE SEVERE THUNDERSTORM WATCH 80 FOR AREAS GENERALLY ALONG AND SOUTHEAST OF A LINE FROM KILLEEN TO ATHENS. STORMS CONTINUE TO DEVELOP IN THESE AREAS WITH ELEVATED CORES OCCASIONALLY PRODUCING QUARTER SIZED HAIL. THUNDERSTORMS WILL GRADUALLY SHIFT EAST OF NORTH TEXAS ALONG WITH THE 850MB FRONT AND THE PRIMARY UPPER TROUGH AXIS. THE WATCH IS IN EFFECT UNTIL 5 PM CDT...BUT WE SHOULD BE ABLE TO CLEAR COUNTIES FROM WEST TO EAST AS WARRANTED BY TRENDS. 30 && .PREV DISCUSSION... /ISSUED 417 AM CDT MON APR 14 2014/ 08Z SURFACE ANALYSIS INDICATED A STRONG COLD FRONT MOVING SOUTHEAST ACROSS THE CWA...LOCATED NEAR A LINE FROM ATHENS TO WACO TO LAMPASAS. JUST TO THE NORTHWEST OF THIS FRONT...A LINE OF SCATTERED SHOWERS AND THUNDERSTORMS WAS OBSERVED...LIKELY ASSOCIATED WITH THE 850 MB REFLECTION OF THE COLD FRONT. AT 0830Z...NONE OF THIS ACTIVITY WAS STRONG IN NATURE...AND AS ALLUDED TO ABOVE...IT IS ALL ELEVATED IN NATURE OVER THE FRONTAL INVERSION. REGIONAL SURFACE OBSERVATIONS INDICATE UNSEASONABLY COLD AIR BEHIND THE FRONT...WITH TEMPERATURES IN THE LOWER 40S LOCATED OVER WICHITA FALLS. NORTH WINDS WERE ALREADY RELATIVELY STRONG BEHIND THE FRONT...WITH MANY LOCATIONS OBSERVING WINDS IN THE 20 TO 25 MPH RANGE EARLY THIS MORNING. THIS MORNING...WENT AHEAD AND CANCELLED THE SEVERE THUNDERSTORM WATCH IN COORDINATION WITH THE SPC AND WFO SHV AS THE COLD FRONT HAD UNDERCUT ALL ONGOING CONVECTION. THIS DOES NOT MEAN IT/S IMPOSSIBLE TO GET STRONG STORMS THIS MORNING...HOWEVER THE ONLY STRONG TO MARGINALLY SEVERE STORM HAZARD ASSOCIATED WITH ELEVATED STORMS IS GOING TO BE IN THE FORM OF HAIL. RAP FORECAST SOUNDINGS INDICATE THE PRESENCE OF 1000-1500 J/KG OF MUCAPE AVAILABLE FOR THESE ELEVATED STORMS. DEEP LAYER SHEAR VALUES LOOK IMPRESSIVE...BUT ARE NOT REALLY RELEVANT FOR THIS ACTIVITY AS THE BULK OF THE CONTRIBUTION TO THE HIGHER SHEAR VALUES OCCURS BELOW THE FRONTAL INVERSION. DEEP LAYER BULK SHEAR CALCULATIONS INDICATE ABOUT 60 KTS OF SHEAR...WHILE EFFECTIVE BULK SHEAR IS MORE REALISTICALLY AROUND 25 KTS. AS A RESULT...STRONG...BUT LIKELY UNORGANIZED ELEVATED CONVECTION IS POSSIBLE THIS MORNING. BASED ON THE RADAR PRESENTATION OF STORMS SO FAR EARLY THIS MORNING...CHANCES ARE NO LARGE HAIL WILL FALL ACROSS THE CWA...HOWEVER IF IT DOES OCCUR...HAIL WILL LIKELY BE CLOSE TO 1 INCH OR QUARTER SIZE IN DIAMETER. REMAINDER OF TODAY...THE 850 MB FRONT WILL SLIDE SOUTHEAST OF THE CWA BY LATE THIS MORNING...TAKING ALL THUNDERSTORM CHANCES SOUTHEAST OUT OF THE AREA IN ITS WAKE. RELATIVELY STRONG ISENTROPIC DOWNGLIDE/COLD AIR ADVECTION WILL DOMINATE THE LOWER TROPOSPHERE IN THE WAKE OF THIS FRONT. A STRONG UPPER LEVEL LOW PRESSURE SYSTEM WILL MOVE FROM WEST TO EAST OVER THE SOUTH PLAINS TODAY...WHICH WILL SPREAD SOME STRONG LARGE SCALE FORCING FOR ASCENT OVER THE CWA THIS AFTERNOON. HOWEVER...THE LARGE SCALE FORCING FOR ASCENT ASSOCIATED WITH THIS UPPER LOW IS NOT EXPECTED TO PENETRATE MUCH DEEPER THAN THE MIDDLE TROPOSPHERE TODAY BECAUSE THE MIDDLE TO LOW TROPOSPHERE WILL BE DEFINED BY HIGH STATIC STABILITY. A THERMODYNAMICALLY STABLE LAYER RESISTS VERTICAL MOTIONS...AND THEREFORE SHOULD PREVENT ANY ADDITIONAL PRECIPITATION FROM DEVELOPING OVER THE CWA TODAY ASSOCIATED WITH THIS UPPER LOW. THIS IS SUCH A STRONG UPPER TROUGH THAT IT WOULD BE A HUGE SURPRISE TO SEE SOME WEAK RADAR RETURNS DEVELOP OVER THE CWA EARLY THIS AFTERNOON...BUT THE COLD FRONT PUSHING THROUGH THE AREA JUST LOOKS TOO STRONG AND COLD TO ALLOW FOR MUCH LIFT TO OCCUR WHERE WE WOULD NEED IT TO GET RAIN SHOWERS...THAT BEING THE MID TO LOWER TROPOSPHERE. ASIDE FROM PRECIPITATION CONCERNS...BEHIND THE FRONT WE SHOULD JUST SEE STRONG NORTH WINDS AND COLD AIR ADVECTION THROUGHOUT THE DAY TODAY. TEMPERATURES ARE EXPECTED TO INCREASE INTO THE LOWER TO MID 50S BY LATE THIS AFTERNOON DESPITE THE STRONG COLD AIR ADVECTION AS SKIES CLEAR OUT RAPIDLY BEHIND THE PASSAGE OF THE UPPER TROUGH. EVEN THOUGH THE AIR BEHIND THE FRONT WILL REMAIN COLD...THE SUN ANGLE IS GETTING TOO HIGH FOR US NOT TO HEAT UP A BIT EVEN WITH JUST A FEW HOURS OF SUNSHINE. A WIND ADVISORY REMAINS IN EFFECT FOR THE ENTIRE AREA TODAY DUE TO NORTH WINDS OF 25 TO 30 MPH BEHIND THE FRONT. WINDS SHOULD DIMINISH AN HOUR OR TWO AFTER SUNSET AS HIGH PRESSURE BEGINS TO MOVE INTO THE REGION. TONIGHT...HIGH PRESSURE IS EXPECTED TO SLIDE SOUTH-SOUTHEAST ACROSS TEXAS FROM THE TX PANHANDLE TONIGHT. THIS WILL RESULT IN NEARLY CALM WINDS ACROSS WEST CENTRAL TEXAS...AND LIGHT NORTHERLY WINDS TO THE EAST. LIGHT WINDS AND CLEAR SKIES WILL MAKE FOR AN IDEAL RADIATIONAL COOLING ENVIRONMENT RESULTING IN TEMPERATURES FALLING INTO THE UPPER 20S TO MID 30S ACROSS THE CWA. YES...YOU READ THAT CORRECTLY...PARTS OF NORTH AND CENTRAL TEXAS ARE EXPECTED TO FALL BELOW FREEZING TONIGHT INTO TUESDAY MORNING. THIS IS PUSHING RECORD TERRITORY FOR A LATE FREEZE WHICH IS QUITE REMARKABLE CONSIDERING RECORDS HAVE BEEN KEPT SINCE THE LATE 1800S TO EARLY 1900S...SO WE ARE LOOKING AT AN EVENT THAT HAS A RETURN INTERVAL OF OVER 100 YEARS...FOR NORTH AND CENTRAL TEXAS AT LEAST. AS A RESULT...THIS FREEZE...ASSUMING IT OCCURS AS FORECAST...HAS THE POTENTIAL TO DO QUITE A BIT OF DAMAGE TO OUTDOOR PLANTS AS MOST FOLKS WOULD NOT HAVE WAITED THIS LONG TO GET THEIR SPRING PLANTING TAKEN CARE OF. AT ANY RATE...THIS IS WHY FREEZE WARNINGS ARE ISSUED...TO GIVE FOLKS A CHANCE TO PROTECT THEIR PLANTS. A FREEZE WARNING IS IN EFFECT FROM 1 AM TO 10 AM TONIGHT/TUESDAY MORNING FOR LOCATIONS ALONG AND NORTHWEST OF A LINE FROM SULPHUR SPRINGS TO KELLER TO WACO TO LAMPASAS. LOCATIONS JUST SOUTHEAST OF THIS LINE GENERALLY HAVE FORECAST LOWS AT 33 DEGREES...SO THIS WARNING MAY BE EXPANDED BASED ON HOW WARM WE GET THIS AFTERNOON AND BASED ON NEW MODEL GUIDANCE THROUGHOUT THE DAY. FORTUNATELY...MOST LOCATIONS IN THE FREEZE WARNING SHOULD SEE LOWS FALL JUST BELOW FREEZING...GENERALLY 30 TO 32 DEGREES. TEMPERATURES FALLING INTO THE UPPER 20S IS MORE LIKELY NORTH OF INTERSTATE 30...NEAR THE RED RIVER. TEMPERATURES ARE MORE LIKELY TO FALL BELOW FREEZING IN RURAL AREAS MORE SO THAN URBAN AREAS. THE URBAN HEAT ISLAND EFFECT WILL KEEP MOST OF THE CONCRETED AREAS OF THE METROPLEX ABOVE FREEZING. TARRANT COUNTY IS INCLUDED IN THE FREEZE WARNING ANYWAYS BECAUSE THE FAR NORTH AND WESTERN PORTIONS OF THE COUNTY...OUTSIDE OF THE 820 LOOP...ARE MORE LIKELY TO SEE FREEZING TEMPERATURES. TEMPERATURES ARE EXPECTED TO CLIMB ABOVE FREEZING AREA WIDE AFTER 10 AM TUESDAY MORNING. FROST IS POSSIBLE IN AREAS NOT INCLUDED IN THE FREEZE WARNING...SO EVEN IF YOU ARE NOT IN THE FREEZE WARNING AT THIS TIME...IT MAY BE PRUDENT TO PROTECT YOUR PLANTS ANYWAYS AS A PRECAUTION. THE AIR IS EXPECTED TO BE VERY DRY...SO WIDESPREAD FROST IS NOT LIKELY...BUT IT MAY BE BETTER TO BE SAFE THAN SORRY. REMAINDER OF THE FORECAST...WE WILL WARM UP AFTER TUESDAY...WITH NO MORE POTENTIAL FROSTS OR FREEZES IN THE FORECAST THROUGH NEXT WEEKEND. TUESDAY NIGHTS LOWS WILL BE WELL BELOW NORMAL AGAIN...BUT SHOULD FALL INTO THE MID TO UPPER 30S AT WORST. BY WEDNESDAY...SOUTH WINDS WILL HELP BRING DEW POINTS BACK UP INTO THE MID TO UPPER 40S...BRINGING ABOUT A RETURN TO MORE SEASONAL TEMPERATURES DURING THE DAYTIME AND OVERNIGHT. OUR NEXT CHANCE OF RAIN STILL LOOKS TO BE THURSDAY...ASSOCIATED WITH AN UPPER LEVEL TROUGH PROGGED TO MOVE OVER THE SOUTHERN PLAINS THURSDAY AFTERNOON. HOWEVER...THE ECMWF AND GFS BOTH KEEP THE BULK OF THE UPPER LEVEL FORCING FOR ASCENT ASSOCIATED WITH THIS TROUGH NORTH OF THE CWA. ASSUMING THIS VERIFIES...THIS DOES NOT USUALLY BODE WELL FOR PRECIPITATION CHANCES...EVEN WITH A WEAK COLD FRONT PUSHING SOUTHEAST ACROSS THE CWA THURSDAY AFTERNOON/EVENING. THE LOSS OF UPPER LEVEL DYNAMICS USUALLY MAKES PRECIPITATION ALONG COLD FRONTS ISOLATED AT BEST. THE CANADIAN IS FURTHER SOUTH WITH THIS UPPER TROUGH...AND THEREFORE HAS MUCH MORE PRECIPITATION FOR THE CWA. WILL CONTINUE TO MONITOR THE EVOLUTION OF THIS TROUGH IN FUTURE FORECASTS...HOWEVER FOR NOW JUST KEPT POPS IN THE 20 TO 30 PERCENT RANGE IN LINE WITH THE GFS/ECMWF SOLUTION. AFTER THURSDAY...OUR NEXT SHOT AT RAIN LOOKS TO BE SATURDAY NIGHT INTO SUNDAY...AS ALL GUIDANCE INDICATES AN UPPER LEVEL TROUGH WILL MOVE OVER THE SOUTHWESTERN CONUS AND TOWARDS NORTH TX AT THAT TIME. THE GFS IS THE MOST AGGRESSIVE WITH TAPPING INTO SOME TROPICAL PACIFIC MOISTURE IN THE UPPER TROPOSPHERE COURTESY OF THE SUB-TROPICAL JET. AS A RESULT THE GFS GIVES THE CWA A GOOD...WIDESPREAD ONE HALF TO ONE INCH OF RAINFALL FROM SATURDAY NIGHT THROUGH SUNDAY. WILL NOT BITE OFF ON THIS SOLUTION QUITE YET...BUT IT IS A GOOD SIGN THAT AT LEAST ALL MODELS HAVE SOME VERSION OF THIS TROUGH OVER THE SOUTHWESTERN CONUS. IF THIS CONSISTENT CONTINUES...POPS WILL BE INCREASED AREA WIDE FOR SATURDAY NIGHT INTO SUNDAY. THIS DOES NOT LOOK TO BE A GOOD SEVERE WEATHER SET UP FOR NOW...SO A GOOD WIDESPREAD RAINFALL WITH EMBEDDED THUNDERSTORMS IS WHAT IS EXPECTED AT THIS TIME. WE WILL SEE HOW THINGS CHANGE AS WE GET CLOSER TO NEXT WEEKEND OF COURSE. CAVANAUGH && .PRELIMINARY POINT TEMPS/POPS... DALLAS-FT. WORTH, TX 55 34 63 42 66 / 10 5 0 0 0 WACO, TX 56 33 63 36 67 / 30 0 0 0 0 PARIS, TX 51 30 59 36 64 / 20 5 0 0 0 DENTON, TX 53 29 62 38 66 / 10 5 0 0 0 MCKINNEY, TX 53 30 62 38 65 / 10 5 0 0 0 DALLAS, TX 56 35 63 42 66 / 10 5 0 0 0 TERRELL, TX 55 33 62 37 65 / 20 5 0 0 0 CORSICANA, TX 54 33 61 38 66 / 30 5 0 0 0 TEMPLE, TX 58 33 64 36 68 / 30 0 0 0 0 MINERAL WELLS, TX 55 32 63 37 69 / 10 0 0 0 0 && .FWD WATCHES/WARNINGS/ADVISORIES... FREEZE WARNING FROM 1 AM TO 10 AM CDT TUESDAY FOR TXZ091>095- 100>107-115>118-129>133-141>145-156-157-159. WIND ADVISORY UNTIL 9 PM CDT THIS EVENING FOR TXZ091>095-100>107- 115>123-129>135-141>148-156>162-174-175. && $$ 58/30
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
1041 AM CDT MON APR 14 2014 .UPDATE... GRIDS HAVE BEEN UPDATED TO INCLUDE SEVERE THUNDERSTORM WATCH 80 FOR AREAS GENERALLY ALONG AND SOUTHEAST OF A LINE FROM KILLEEN TO ATHENS. STORMS CONTINUE TO DEVELOP IN THESE AREAS WITH ELEVATED CORES OCCASIONALLY PRODUCING QUARTER SIZED HAIL. THUNDERSTORMS WILL GRADUALLY SHIFT EAST OF NORTH TEXAS ALONG WITH THE 850MB FRONT AND THE PRIMARY UPPER TROUGH AXIS. THE WATCH IS IN EFFECT UNTIL 5 PM CDT...BUT WE SHOULD BE ABLE TO CLEAR COUNTIES FROM WEST TO EAST AS WARRANTED BY TRENDS. 30 && .AVIATION... /12Z TAFS/ MVFR CONDITIONS WILL PREVAIL THROUGH THE MORNING WITH GUSTY NORTH WINDS EXPECTED MOST OF THE DAY. EXTENSIVE CLOUDINESS WILL BEGIN TO SCATTER OUT THIS AFTERNOON AS DRIER AIR MIXES DOWN. VFR CONDITIONS EXPECTED LATER TODAY THROUGH TUESDAY. WINDS WILL DIMINISH THIS EVENING BECOMING LGT/VAR BY EARLY TUESDAY...THEN SOUTHERLY AROUND 10KTS TUESDAY AFTERNOON. DUNN && .PREV UPDATE... .UPDATE... ELEVATED CONVECTION NEAR WAXAHACHIE...HILLSBORO...CORSICANA AND SURROUNDING AREAS WILL CONTINUE TO LIFT NORTHEAST AS AN UPPER TROUGH DIGS SOUTHEAST ACROSS THE CENTRAL AND SOUTHERN PLAINS. WE DID A QUICK UPDATE TO INCLUDE POPS THIS MORNING FOR AREAS IMMEDIATELY EAST AND SOUTH OF DALLAS. ACTIVITY WILL SHIFT EAST OF THE AREA BY EARLY AFTERNOON ALONG WITH THE TROUGH AXIS. OTHERWISE STRONG NORTH WINDS WILL CONTINUE THROUGH THE AFTERNOON. CLOUDS AND COLD ADVECTION WILL KEEP A LID ON TEMPERATURES...WILL KEEP AN EYE ON TRENDS TO SEE IF AFTERNOON HIGHS NEED TO BE LOWERED AT ALL. RECORD LOW MAX AT DFW IS 55 FOR TODAY...AND 56 AT WACO SO IT WILL BE CLOSE. 30 && .PREV DISCUSSION... /ISSUED 417 AM CDT MON APR 14 2014/ 08Z SURFACE ANALYSIS INDICATED A STRONG COLD FRONT MOVING SOUTHEAST ACROSS THE CWA...LOCATED NEAR A LINE FROM ATHENS TO WACO TO LAMPASAS. JUST TO THE NORTHWEST OF THIS FRONT...A LINE OF SCATTERED SHOWERS AND THUNDERSTORMS WAS OBSERVED...LIKELY ASSOCIATED WITH THE 850 MB REFLECTION OF THE COLD FRONT. AT 0830Z...NONE OF THIS ACTIVITY WAS STRONG IN NATURE...AND AS ALLUDED TO ABOVE...IT IS ALL ELEVATED IN NATURE OVER THE FRONTAL INVERSION. REGIONAL SURFACE OBSERVATIONS INDICATE UNSEASONABLY COLD AIR BEHIND THE FRONT...WITH TEMPERATURES IN THE LOWER 40S LOCATED OVER WICHITA FALLS. NORTH WINDS WERE ALREADY RELATIVELY STRONG BEHIND THE FRONT...WITH MANY LOCATIONS OBSERVING WINDS IN THE 20 TO 25 MPH RANGE EARLY THIS MORNING. THIS MORNING...WENT AHEAD AND CANCELLED THE SEVERE THUNDERSTORM WATCH IN COORDINATION WITH THE SPC AND WFO SHV AS THE COLD FRONT HAD UNDERCUT ALL ONGOING CONVECTION. THIS DOES NOT MEAN IT/S IMPOSSIBLE TO GET STRONG STORMS THIS MORNING...HOWEVER THE ONLY STRONG TO MARGINALLY SEVERE STORM HAZARD ASSOCIATED WITH ELEVATED STORMS IS GOING TO BE IN THE FORM OF HAIL. RAP FORECAST SOUNDINGS INDICATE THE PRESENCE OF 1000-1500 J/KG OF MUCAPE AVAILABLE FOR THESE ELEVATED STORMS. DEEP LAYER SHEAR VALUES LOOK IMPRESSIVE...BUT ARE NOT REALLY RELEVANT FOR THIS ACTIVITY AS THE BULK OF THE CONTRIBUTION TO THE HIGHER SHEAR VALUES OCCURS BELOW THE FRONTAL INVERSION. DEEP LAYER BULK SHEAR CALCULATIONS INDICATE ABOUT 60 KTS OF SHEAR...WHILE EFFECTIVE BULK SHEAR IS MORE REALISTICALLY AROUND 25 KTS. AS A RESULT...STRONG...BUT LIKELY UNORGANIZED ELEVATED CONVECTION IS POSSIBLE THIS MORNING. BASED ON THE RADAR PRESENTATION OF STORMS SO FAR EARLY THIS MORNING...CHANCES ARE NO LARGE HAIL WILL FALL ACROSS THE CWA...HOWEVER IF IT DOES OCCUR...HAIL WILL LIKELY BE CLOSE TO 1 INCH OR QUARTER SIZE IN DIAMETER. REMAINDER OF TODAY...THE 850 MB FRONT WILL SLIDE SOUTHEAST OF THE CWA BY LATE THIS MORNING...TAKING ALL THUNDERSTORM CHANCES SOUTHEAST OUT OF THE AREA IN ITS WAKE. RELATIVELY STRONG ISENTROPIC DOWNGLIDE/COLD AIR ADVECTION WILL DOMINATE THE LOWER TROPOSPHERE IN THE WAKE OF THIS FRONT. A STRONG UPPER LEVEL LOW PRESSURE SYSTEM WILL MOVE FROM WEST TO EAST OVER THE SOUTH PLAINS TODAY...WHICH WILL SPREAD SOME STRONG LARGE SCALE FORCING FOR ASCENT OVER THE CWA THIS AFTERNOON. HOWEVER...THE LARGE SCALE FORCING FOR ASCENT ASSOCIATED WITH THIS UPPER LOW IS NOT EXPECTED TO PENETRATE MUCH DEEPER THAN THE MIDDLE TROPOSPHERE TODAY BECAUSE THE MIDDLE TO LOW TROPOSPHERE WILL BE DEFINED BY HIGH STATIC STABILITY. A THERMODYNAMICALLY STABLE LAYER RESISTS VERTICAL MOTIONS...AND THEREFORE SHOULD PREVENT ANY ADDITIONAL PRECIPITATION FROM DEVELOPING OVER THE CWA TODAY ASSOCIATED WITH THIS UPPER LOW. THIS IS SUCH A STRONG UPPER TROUGH THAT IT WOULD BE A HUGE SURPRISE TO SEE SOME WEAK RADAR RETURNS DEVELOP OVER THE CWA EARLY THIS AFTERNOON...BUT THE COLD FRONT PUSHING THROUGH THE AREA JUST LOOKS TOO STRONG AND COLD TO ALLOW FOR MUCH LIFT TO OCCUR WHERE WE WOULD NEED IT TO GET RAIN SHOWERS...THAT BEING THE MID TO LOWER TROPOSPHERE. ASIDE FROM PRECIPITATION CONCERNS...BEHIND THE FRONT WE SHOULD JUST SEE STRONG NORTH WINDS AND COLD AIR ADVECTION THROUGHOUT THE DAY TODAY. TEMPERATURES ARE EXPECTED TO INCREASE INTO THE LOWER TO MID 50S BY LATE THIS AFTERNOON DESPITE THE STRONG COLD AIR ADVECTION AS SKIES CLEAR OUT RAPIDLY BEHIND THE PASSAGE OF THE UPPER TROUGH. EVEN THOUGH THE AIR BEHIND THE FRONT WILL REMAIN COLD...THE SUN ANGLE IS GETTING TOO HIGH FOR US NOT TO HEAT UP A BIT EVEN WITH JUST A FEW HOURS OF SUNSHINE. A WIND ADVISORY REMAINS IN EFFECT FOR THE ENTIRE AREA TODAY DUE TO NORTH WINDS OF 25 TO 30 MPH BEHIND THE FRONT. WINDS SHOULD DIMINISH AN HOUR OR TWO AFTER SUNSET AS HIGH PRESSURE BEGINS TO MOVE INTO THE REGION. TONIGHT...HIGH PRESSURE IS EXPECTED TO SLIDE SOUTH-SOUTHEAST ACROSS TEXAS FROM THE TX PANHANDLE TONIGHT. THIS WILL RESULT IN NEARLY CALM WINDS ACROSS WEST CENTRAL TEXAS...AND LIGHT NORTHERLY WINDS TO THE EAST. LIGHT WINDS AND CLEAR SKIES WILL MAKE FOR AN IDEAL RADIATIONAL COOLING ENVIRONMENT RESULTING IN TEMPERATURES FALLING INTO THE UPPER 20S TO MID 30S ACROSS THE CWA. YES...YOU READ THAT CORRECTLY...PARTS OF NORTH AND CENTRAL TEXAS ARE EXPECTED TO FALL BELOW FREEZING TONIGHT INTO TUESDAY MORNING. THIS IS PUSHING RECORD TERRITORY FOR A LATE FREEZE WHICH IS QUITE REMARKABLE CONSIDERING RECORDS HAVE BEEN KEPT SINCE THE LATE 1800S TO EARLY 1900S...SO WE ARE LOOKING AT AN EVENT THAT HAS A RETURN INTERVAL OF OVER 100 YEARS...FOR NORTH AND CENTRAL TEXAS AT LEAST. AS A RESULT...THIS FREEZE...ASSUMING IT OCCURS AS FORECAST...HAS THE POTENTIAL TO DO QUITE A BIT OF DAMAGE TO OUTDOOR PLANTS AS MOST FOLKS WOULD NOT HAVE WAITED THIS LONG TO GET THEIR SPRING PLANTING TAKEN CARE OF. AT ANY RATE...THIS IS WHY FREEZE WARNINGS ARE ISSUED...TO GIVE FOLKS A CHANCE TO PROTECT THEIR PLANTS. A FREEZE WARNING IS IN EFFECT FROM 1 AM TO 10 AM TONIGHT/TUESDAY MORNING FOR LOCATIONS ALONG AND NORTHWEST OF A LINE FROM SULPHUR SPRINGS TO KELLER TO WACO TO LAMPASAS. LOCATIONS JUST SOUTHEAST OF THIS LINE GENERALLY HAVE FORECAST LOWS AT 33 DEGREES...SO THIS WARNING MAY BE EXPANDED BASED ON HOW WARM WE GET THIS AFTERNOON AND BASED ON NEW MODEL GUIDANCE THROUGHOUT THE DAY. FORTUNATELY...MOST LOCATIONS IN THE FREEZE WARNING SHOULD SEE LOWS FALL JUST BELOW FREEZING...GENERALLY 30 TO 32 DEGREES. TEMPERATURES FALLING INTO THE UPPER 20S IS MORE LIKELY NORTH OF INTERSTATE 30...NEAR THE RED RIVER. TEMPERATURES ARE MORE LIKELY TO FALL BELOW FREEZING IN RURAL AREAS MORE SO THAN URBAN AREAS. THE URBAN HEAT ISLAND EFFECT WILL KEEP MOST OF THE CONCRETED AREAS OF THE METROPLEX ABOVE FREEZING. TARRANT COUNTY IS INCLUDED IN THE FREEZE WARNING ANYWAYS BECAUSE THE FAR NORTH AND WESTERN PORTIONS OF THE COUNTY...OUTSIDE OF THE 820 LOOP...ARE MORE LIKELY TO SEE FREEZING TEMPERATURES. TEMPERATURES ARE EXPECTED TO CLIMB ABOVE FREEZING AREA WIDE AFTER 10 AM TUESDAY MORNING. FROST IS POSSIBLE IN AREAS NOT INCLUDED IN THE FREEZE WARNING...SO EVEN IF YOU ARE NOT IN THE FREEZE WARNING AT THIS TIME...IT MAY BE PRUDENT TO PROTECT YOUR PLANTS ANYWAYS AS A PRECAUTION. THE AIR IS EXPECTED TO BE VERY DRY...SO WIDESPREAD FROST IS NOT LIKELY...BUT IT MAY BE BETTER TO BE SAFE THAN SORRY. REMAINDER OF THE FORECAST...WE WILL WARM UP AFTER TUESDAY...WITH NO MORE POTENTIAL FROSTS OR FREEZES IN THE FORECAST THROUGH NEXT WEEKEND. TUESDAY NIGHTS LOWS WILL BE WELL BELOW NORMAL AGAIN...BUT SHOULD FALL INTO THE MID TO UPPER 30S AT WORST. BY WEDNESDAY...SOUTH WINDS WILL HELP BRING DEW POINTS BACK UP INTO THE MID TO UPPER 40S...BRINGING ABOUT A RETURN TO MORE SEASONAL TEMPERATURES DURING THE DAYTIME AND OVERNIGHT. OUR NEXT CHANCE OF RAIN STILL LOOKS TO BE THURSDAY...ASSOCIATED WITH AN UPPER LEVEL TROUGH PROGGED TO MOVE OVER THE SOUTHERN PLAINS THURSDAY AFTERNOON. HOWEVER...THE ECMWF AND GFS BOTH KEEP THE BULK OF THE UPPER LEVEL FORCING FOR ASCENT ASSOCIATED WITH THIS TROUGH NORTH OF THE CWA. ASSUMING THIS VERIFIES...THIS DOES NOT USUALLY BODE WELL FOR PRECIPITATION CHANCES...EVEN WITH A WEAK COLD FRONT PUSHING SOUTHEAST ACROSS THE CWA THURSDAY AFTERNOON/EVENING. THE LOSS OF UPPER LEVEL DYNAMICS USUALLY MAKES PRECIPITATION ALONG COLD FRONTS ISOLATED AT BEST. THE CANADIAN IS FURTHER SOUTH WITH THIS UPPER TROUGH...AND THEREFORE HAS MUCH MORE PRECIPITATION FOR THE CWA. WILL CONTINUE TO MONITOR THE EVOLUTION OF THIS TROUGH IN FUTURE FORECASTS...HOWEVER FOR NOW JUST KEPT POPS IN THE 20 TO 30 PERCENT RANGE IN LINE WITH THE GFS/ECMWF SOLUTION. AFTER THURSDAY...OUR NEXT SHOT AT RAIN LOOKS TO BE SATURDAY NIGHT INTO SUNDAY...AS ALL GUIDANCE INDICATES AN UPPER LEVEL TROUGH WILL MOVE OVER THE SOUTHWESTERN CONUS AND TOWARDS NORTH TX AT THAT TIME. THE GFS IS THE MOST AGGRESSIVE WITH TAPPING INTO SOME TROPICAL PACIFIC MOISTURE IN THE UPPER TROPOSPHERE COURTESY OF THE SUB-TROPICAL JET. AS A RESULT THE GFS GIVES THE CWA A GOOD...WIDESPREAD ONE HALF TO ONE INCH OF RAINFALL FROM SATURDAY NIGHT THROUGH SUNDAY. WILL NOT BITE OFF ON THIS SOLUTION QUITE YET...BUT IT IS A GOOD SIGN THAT AT LEAST ALL MODELS HAVE SOME VERSION OF THIS TROUGH OVER THE SOUTHWESTERN CONUS. IF THIS CONSISTENT CONTINUES...POPS WILL BE INCREASED AREA WIDE FOR SATURDAY NIGHT INTO SUNDAY. THIS DOES NOT LOOK TO BE A GOOD SEVERE WEATHER SET UP FOR NOW...SO A GOOD WIDESPREAD RAINFALL WITH EMBEDDED THUNDERSTORMS IS WHAT IS EXPECTED AT THIS TIME. WE WILL SEE HOW THINGS CHANGE AS WE GET CLOSER TO NEXT WEEKEND OF COURSE. CAVANAUGH && .PRELIMINARY POINT TEMPS/POPS... DALLAS-FT. WORTH, TX 55 34 63 42 66 / 10 5 0 0 0 WACO, TX 56 33 63 36 67 / 30 0 0 0 0 PARIS, TX 51 30 59 36 64 / 20 5 0 0 0 DENTON, TX 53 29 62 38 66 / 10 5 0 0 0 MCKINNEY, TX 53 30 62 38 65 / 10 5 0 0 0 DALLAS, TX 56 35 63 42 66 / 10 5 0 0 0 TERRELL, TX 55 33 62 37 65 / 20 5 0 0 0 CORSICANA, TX 54 33 61 38 66 / 30 5 0 0 0 TEMPLE, TX 58 33 64 36 68 / 30 0 0 0 0 MINERAL WELLS, TX 55 32 63 37 69 / 10 0 0 0 0 && .FWD WATCHES/WARNINGS/ADVISORIES... FREEZE WARNING FROM 1 AM TO 10 AM CDT TUESDAY FOR TXZ091>095- 100>107-115>118-129>133-141>145-156-157-159. WIND ADVISORY UNTIL 9 PM CDT THIS EVENING FOR TXZ091>095-100>107- 115>123-129>135-141>148-156>162-174-175. && $$ 58/30
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
842 AM CDT MON APR 14 2014 .UPDATE... ELEVATED CONVECTION NEAR WAXAHACHIE...HILLSBORO...CORSICANA AND SURROUNDING AREAS WILL CONTINUE TO LIFT NORTHEAST AS AN UPPER TROUGH DIGS SOUTHEAST ACROSS THE CENTRAL AND SOUTHERN PLAINS. WE DID A QUICK UPDATE TO INCLUDE POPS THIS MORNING FOR AREAS IMMEDIATELY EAST AND SOUTH OF DALLAS. ACTIVITY WILL SHIFT EAST OF THE AREA BY EARLY AFTERNOON ALONG WITH THE TROUGH AXIS. OTHERWISE STRONG NORTH WINDS WILL CONTINUE THROUGH THE AFTERNOON. CLOUDS AND COLD ADVECTION WILL KEEP A LID ON TEMPERATURES...WILL KEEP AN EYE ON TRENDS TO SEE IF AFTERNOON HIGHS NEED TO BE LOWERED AT ALL. RECORD LOW MAX AT DFW IS 55 FOR TODAY...AND 56 AT WACO SO IT WILL BE CLOSE. 30 && .AVIATION... /12Z TAFS/ MVFR CONDITIONS WILL PREVAIL THROUGH THE MORNING WITH GUSTY NORTH WINDS EXPECTED MOST OF THE DAY. EXTENSIVE CLOUDINESS WILL BEGIN TO SCATTER OUT THIS AFTERNOON AS DRIER AIR MIXES DOWN. VFR CONDITIONS EXPECTED LATER TODAY THROUGH TUESDAY. WINDS WILL DIMINISH THIS EVENING BECOMING LGT/VAR BY EARLY TUESDAY...THEN SOUTHERLY AROUND 10KTS TUESDAY AFTERNOON. DUNN && .PREV DISCUSSION... /ISSUED 417 AM CDT MON APR 14 2014/ 08Z SURFACE ANALYSIS INDICATED A STRONG COLD FRONT MOVING SOUTHEAST ACROSS THE CWA...LOCATED NEAR A LINE FROM ATHENS TO WACO TO LAMPASAS. JUST TO THE NORTHWEST OF THIS FRONT...A LINE OF SCATTERED SHOWERS AND THUNDERSTORMS WAS OBSERVED...LIKELY ASSOCIATED WITH THE 850 MB REFLECTION OF THE COLD FRONT. AT 0830Z...NONE OF THIS ACTIVITY WAS STRONG IN NATURE...AND AS ALLUDED TO ABOVE...IT IS ALL ELEVATED IN NATURE OVER THE FRONTAL INVERSION. REGIONAL SURFACE OBSERVATIONS INDICATE UNSEASONABLY COLD AIR BEHIND THE FRONT...WITH TEMPERATURES IN THE LOWER 40S LOCATED OVER WICHITA FALLS. NORTH WINDS WERE ALREADY RELATIVELY STRONG BEHIND THE FRONT...WITH MANY LOCATIONS OBSERVING WINDS IN THE 20 TO 25 MPH RANGE EARLY THIS MORNING. THIS MORNING...WENT AHEAD AND CANCELLED THE SEVERE THUNDERSTORM WATCH IN COORDINATION WITH THE SPC AND WFO SHV AS THE COLD FRONT HAD UNDERCUT ALL ONGOING CONVECTION. THIS DOES NOT MEAN IT/S IMPOSSIBLE TO GET STRONG STORMS THIS MORNING...HOWEVER THE ONLY STRONG TO MARGINALLY SEVERE STORM HAZARD ASSOCIATED WITH ELEVATED STORMS IS GOING TO BE IN THE FORM OF HAIL. RAP FORECAST SOUNDINGS INDICATE THE PRESENCE OF 1000-1500 J/KG OF MUCAPE AVAILABLE FOR THESE ELEVATED STORMS. DEEP LAYER SHEAR VALUES LOOK IMPRESSIVE...BUT ARE NOT REALLY RELEVANT FOR THIS ACTIVITY AS THE BULK OF THE CONTRIBUTION TO THE HIGHER SHEAR VALUES OCCURS BELOW THE FRONTAL INVERSION. DEEP LAYER BULK SHEAR CALCULATIONS INDICATE ABOUT 60 KTS OF SHEAR...WHILE EFFECTIVE BULK SHEAR IS MORE REALISTICALLY AROUND 25 KTS. AS A RESULT...STRONG...BUT LIKELY UNORGANIZED ELEVATED CONVECTION IS POSSIBLE THIS MORNING. BASED ON THE RADAR PRESENTATION OF STORMS SO FAR EARLY THIS MORNING...CHANCES ARE NO LARGE HAIL WILL FALL ACROSS THE CWA...HOWEVER IF IT DOES OCCUR...HAIL WILL LIKELY BE CLOSE TO 1 INCH OR QUARTER SIZE IN DIAMETER. REMAINDER OF TODAY...THE 850 MB FRONT WILL SLIDE SOUTHEAST OF THE CWA BY LATE THIS MORNING...TAKING ALL THUNDERSTORM CHANCES SOUTHEAST OUT OF THE AREA IN ITS WAKE. RELATIVELY STRONG ISENTROPIC DOWNGLIDE/COLD AIR ADVECTION WILL DOMINATE THE LOWER TROPOSPHERE IN THE WAKE OF THIS FRONT. A STRONG UPPER LEVEL LOW PRESSURE SYSTEM WILL MOVE FROM WEST TO EAST OVER THE SOUTH PLAINS TODAY...WHICH WILL SPREAD SOME STRONG LARGE SCALE FORCING FOR ASCENT OVER THE CWA THIS AFTERNOON. HOWEVER...THE LARGE SCALE FORCING FOR ASCENT ASSOCIATED WITH THIS UPPER LOW IS NOT EXPECTED TO PENETRATE MUCH DEEPER THAN THE MIDDLE TROPOSPHERE TODAY BECAUSE THE MIDDLE TO LOW TROPOSPHERE WILL BE DEFINED BY HIGH STATIC STABILITY. A THERMODYNAMICALLY STABLE LAYER RESISTS VERTICAL MOTIONS...AND THEREFORE SHOULD PREVENT ANY ADDITIONAL PRECIPITATION FROM DEVELOPING OVER THE CWA TODAY ASSOCIATED WITH THIS UPPER LOW. THIS IS SUCH A STRONG UPPER TROUGH THAT IT WOULD BE A HUGE SURPRISE TO SEE SOME WEAK RADAR RETURNS DEVELOP OVER THE CWA EARLY THIS AFTERNOON...BUT THE COLD FRONT PUSHING THROUGH THE AREA JUST LOOKS TOO STRONG AND COLD TO ALLOW FOR MUCH LIFT TO OCCUR WHERE WE WOULD NEED IT TO GET RAIN SHOWERS...THAT BEING THE MID TO LOWER TROPOSPHERE. ASIDE FROM PRECIPITATION CONCERNS...BEHIND THE FRONT WE SHOULD JUST SEE STRONG NORTH WINDS AND COLD AIR ADVECTION THROUGHOUT THE DAY TODAY. TEMPERATURES ARE EXPECTED TO INCREASE INTO THE LOWER TO MID 50S BY LATE THIS AFTERNOON DESPITE THE STRONG COLD AIR ADVECTION AS SKIES CLEAR OUT RAPIDLY BEHIND THE PASSAGE OF THE UPPER TROUGH. EVEN THOUGH THE AIR BEHIND THE FRONT WILL REMAIN COLD...THE SUN ANGLE IS GETTING TOO HIGH FOR US NOT TO HEAT UP A BIT EVEN WITH JUST A FEW HOURS OF SUNSHINE. A WIND ADVISORY REMAINS IN EFFECT FOR THE ENTIRE AREA TODAY DUE TO NORTH WINDS OF 25 TO 30 MPH BEHIND THE FRONT. WINDS SHOULD DIMINISH AN HOUR OR TWO AFTER SUNSET AS HIGH PRESSURE BEGINS TO MOVE INTO THE REGION. TONIGHT...HIGH PRESSURE IS EXPECTED TO SLIDE SOUTH-SOUTHEAST ACROSS TEXAS FROM THE TX PANHANDLE TONIGHT. THIS WILL RESULT IN NEARLY CALM WINDS ACROSS WEST CENTRAL TEXAS...AND LIGHT NORTHERLY WINDS TO THE EAST. LIGHT WINDS AND CLEAR SKIES WILL MAKE FOR AN IDEAL RADIATIONAL COOLING ENVIRONMENT RESULTING IN TEMPERATURES FALLING INTO THE UPPER 20S TO MID 30S ACROSS THE CWA. YES...YOU READ THAT CORRECTLY...PARTS OF NORTH AND CENTRAL TEXAS ARE EXPECTED TO FALL BELOW FREEZING TONIGHT INTO TUESDAY MORNING. THIS IS PUSHING RECORD TERRITORY FOR A LATE FREEZE WHICH IS QUITE REMARKABLE CONSIDERING RECORDS HAVE BEEN KEPT SINCE THE LATE 1800S TO EARLY 1900S...SO WE ARE LOOKING AT AN EVENT THAT HAS A RETURN INTERVAL OF OVER 100 YEARS...FOR NORTH AND CENTRAL TEXAS AT LEAST. AS A RESULT...THIS FREEZE...ASSUMING IT OCCURS AS FORECAST...HAS THE POTENTIAL TO DO QUITE A BIT OF DAMAGE TO OUTDOOR PLANTS AS MOST FOLKS WOULD NOT HAVE WAITED THIS LONG TO GET THEIR SPRING PLANTING TAKEN CARE OF. AT ANY RATE...THIS IS WHY FREEZE WARNINGS ARE ISSUED...TO GIVE FOLKS A CHANCE TO PROTECT THEIR PLANTS. A FREEZE WARNING IS IN EFFECT FROM 1 AM TO 10 AM TONIGHT/TUESDAY MORNING FOR LOCATIONS ALONG AND NORTHWEST OF A LINE FROM SULPHUR SPRINGS TO KELLER TO WACO TO LAMPASAS. LOCATIONS JUST SOUTHEAST OF THIS LINE GENERALLY HAVE FORECAST LOWS AT 33 DEGREES...SO THIS WARNING MAY BE EXPANDED BASED ON HOW WARM WE GET THIS AFTERNOON AND BASED ON NEW MODEL GUIDANCE THROUGHOUT THE DAY. FORTUNATELY...MOST LOCATIONS IN THE FREEZE WARNING SHOULD SEE LOWS FALL JUST BELOW FREEZING...GENERALLY 30 TO 32 DEGREES. TEMPERATURES FALLING INTO THE UPPER 20S IS MORE LIKELY NORTH OF INTERSTATE 30...NEAR THE RED RIVER. TEMPERATURES ARE MORE LIKELY TO FALL BELOW FREEZING IN RURAL AREAS MORE SO THAN URBAN AREAS. THE URBAN HEAT ISLAND EFFECT WILL KEEP MOST OF THE CONCRETED AREAS OF THE METROPLEX ABOVE FREEZING. TARRANT COUNTY IS INCLUDED IN THE FREEZE WARNING ANYWAYS BECAUSE THE FAR NORTH AND WESTERN PORTIONS OF THE COUNTY...OUTSIDE OF THE 820 LOOP...ARE MORE LIKELY TO SEE FREEZING TEMPERATURES. TEMPERATURES ARE EXPECTED TO CLIMB ABOVE FREEZING AREA WIDE AFTER 10 AM TUESDAY MORNING. FROST IS POSSIBLE IN AREAS NOT INCLUDED IN THE FREEZE WARNING...SO EVEN IF YOU ARE NOT IN THE FREEZE WARNING AT THIS TIME...IT MAY BE PRUDENT TO PROTECT YOUR PLANTS ANYWAYS AS A PRECAUTION. THE AIR IS EXPECTED TO BE VERY DRY...SO WIDESPREAD FROST IS NOT LIKELY...BUT IT MAY BE BETTER TO BE SAFE THAN SORRY. REMAINDER OF THE FORECAST...WE WILL WARM UP AFTER TUESDAY...WITH NO MORE POTENTIAL FROSTS OR FREEZES IN THE FORECAST THROUGH NEXT WEEKEND. TUESDAY NIGHTS LOWS WILL BE WELL BELOW NORMAL AGAIN...BUT SHOULD FALL INTO THE MID TO UPPER 30S AT WORST. BY WEDNESDAY...SOUTH WINDS WILL HELP BRING DEW POINTS BACK UP INTO THE MID TO UPPER 40S...BRINGING ABOUT A RETURN TO MORE SEASONAL TEMPERATURES DURING THE DAYTIME AND OVERNIGHT. OUR NEXT CHANCE OF RAIN STILL LOOKS TO BE THURSDAY...ASSOCIATED WITH AN UPPER LEVEL TROUGH PROGGED TO MOVE OVER THE SOUTHERN PLAINS THURSDAY AFTERNOON. HOWEVER...THE ECMWF AND GFS BOTH KEEP THE BULK OF THE UPPER LEVEL FORCING FOR ASCENT ASSOCIATED WITH THIS TROUGH NORTH OF THE CWA. ASSUMING THIS VERIFIES...THIS DOES NOT USUALLY BODE WELL FOR PRECIPITATION CHANCES...EVEN WITH A WEAK COLD FRONT PUSHING SOUTHEAST ACROSS THE CWA THURSDAY AFTERNOON/EVENING. THE LOSS OF UPPER LEVEL DYNAMICS USUALLY MAKES PRECIPITATION ALONG COLD FRONTS ISOLATED AT BEST. THE CANADIAN IS FURTHER SOUTH WITH THIS UPPER TROUGH...AND THEREFORE HAS MUCH MORE PRECIPITATION FOR THE CWA. WILL CONTINUE TO MONITOR THE EVOLUTION OF THIS TROUGH IN FUTURE FORECASTS...HOWEVER FOR NOW JUST KEPT POPS IN THE 20 TO 30 PERCENT RANGE IN LINE WITH THE GFS/ECMWF SOLUTION. AFTER THURSDAY...OUR NEXT SHOT AT RAIN LOOKS TO BE SATURDAY NIGHT INTO SUNDAY...AS ALL GUIDANCE INDICATES AN UPPER LEVEL TROUGH WILL MOVE OVER THE SOUTHWESTERN CONUS AND TOWARDS NORTH TX AT THAT TIME. THE GFS IS THE MOST AGGRESSIVE WITH TAPPING INTO SOME TROPICAL PACIFIC MOISTURE IN THE UPPER TROPOSPHERE COURTESY OF THE SUB-TROPICAL JET. AS A RESULT THE GFS GIVES THE CWA A GOOD...WIDESPREAD ONE HALF TO ONE INCH OF RAINFALL FROM SATURDAY NIGHT THROUGH SUNDAY. WILL NOT BITE OFF ON THIS SOLUTION QUITE YET...BUT IT IS A GOOD SIGN THAT AT LEAST ALL MODELS HAVE SOME VERSION OF THIS TROUGH OVER THE SOUTHWESTERN CONUS. IF THIS CONSISTENT CONTINUES...POPS WILL BE INCREASED AREA WIDE FOR SATURDAY NIGHT INTO SUNDAY. THIS DOES NOT LOOK TO BE A GOOD SEVERE WEATHER SET UP FOR NOW...SO A GOOD WIDESPREAD RAINFALL WITH EMBEDDED THUNDERSTORMS IS WHAT IS EXPECTED AT THIS TIME. WE WILL SEE HOW THINGS CHANGE AS WE GET CLOSER TO NEXT WEEKEND OF COURSE. CAVANAUGH && .PRELIMINARY POINT TEMPS/POPS... DALLAS-FT. WORTH, TX 55 34 63 42 66 / 10 5 0 0 0 WACO, TX 56 33 63 36 67 / 20 0 0 0 0 PARIS, TX 51 30 59 36 64 / 10 5 0 0 0 DENTON, TX 53 29 62 38 66 / 10 5 0 0 0 MCKINNEY, TX 53 30 62 38 65 / 10 5 0 0 0 DALLAS, TX 56 35 63 42 66 / 10 5 0 0 0 TERRELL, TX 55 33 62 37 65 / 20 5 0 0 0 CORSICANA, TX 54 33 61 38 66 / 30 5 0 0 0 TEMPLE, TX 58 33 64 36 68 / 30 0 0 0 0 MINERAL WELLS, TX 55 32 63 37 69 / 10 0 0 0 0 && .FWD WATCHES/WARNINGS/ADVISORIES... FREEZE WARNING FROM 1 AM TO 10 AM CDT TUESDAY FOR TXZ091>095- 100>107-115>118-129>133-141>145-156-157-159. WIND ADVISORY UNTIL 9 PM CDT THIS EVENING FOR TXZ091>095-100>107- 115>123-129>135-141>148-156>162-174-175. && $$ 58/30
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
639 AM CDT MON APR 14 2014 .AVIATION... /12Z TAFS/ MVFR CONDITIONS WILL PREVAIL THROUGH THE MORNING WITH GUSTY NORTH WINDS EXPECTED MOST OF THE DAY. EXTENSIVE CLOUDINESS WILL BEGIN TO SCATTER OUT THIS AFTERNOON AS DRIER AIR MIXES DOWN. VFR CONDITIONS EXPECTED LATER TODAY THROUGH TUESDAY. WINDS WILL DIMINISH THIS EVENING BECOMING LGT/VAR BY EARLY TUESDAY...THEN SOUTHERLY AROUND 10KTS TUESDAY AFTERNOON. DUNN && .PREV DISCUSSION... /ISSUED 417 AM CDT MON APR 14 2014/ 08Z SURFACE ANALYSIS INDICATED A STRONG COLD FRONT MOVING SOUTHEAST ACROSS THE CWA...LOCATED NEAR A LINE FROM ATHENS TO WACO TO LAMPASAS. JUST TO THE NORTHWEST OF THIS FRONT...A LINE OF SCATTERED SHOWERS AND THUNDERSTORMS WAS OBSERVED...LIKELY ASSOCIATED WITH THE 850 MB REFLECTION OF THE COLD FRONT. AT 0830Z...NONE OF THIS ACTIVITY WAS STRONG IN NATURE...AND AS ALLUDED TO ABOVE...IT IS ALL ELEVATED IN NATURE OVER THE FRONTAL INVERSION. REGIONAL SURFACE OBSERVATIONS INDICATE UNSEASONABLY COLD AIR BEHIND THE FRONT...WITH TEMPERATURES IN THE LOWER 40S LOCATED OVER WICHITA FALLS. NORTH WINDS WERE ALREADY RELATIVELY STRONG BEHIND THE FRONT...WITH MANY LOCATIONS OBSERVING WINDS IN THE 20 TO 25 MPH RANGE EARLY THIS MORNING. THIS MORNING...WENT AHEAD AND CANCELLED THE SEVERE THUNDERSTORM WATCH IN COORDINATION WITH THE SPC AND WFO SHV AS THE COLD FRONT HAD UNDERCUT ALL ONGOING CONVECTION. THIS DOES NOT MEAN IT/S IMPOSSIBLE TO GET STRONG STORMS THIS MORNING...HOWEVER THE ONLY STRONG TO MARGINALLY SEVERE STORM HAZARD ASSOCIATED WITH ELEVATED STORMS IS GOING TO BE IN THE FORM OF HAIL. RAP FORECAST SOUNDINGS INDICATE THE PRESENCE OF 1000-1500 J/KG OF MUCAPE AVAILABLE FOR THESE ELEVATED STORMS. DEEP LAYER SHEAR VALUES LOOK IMPRESSIVE...BUT ARE NOT REALLY RELEVANT FOR THIS ACTIVITY AS THE BULK OF THE CONTRIBUTION TO THE HIGHER SHEAR VALUES OCCURS BELOW THE FRONTAL INVERSION. DEEP LAYER BULK SHEAR CALCULATIONS INDICATE ABOUT 60 KTS OF SHEAR...WHILE EFFECTIVE BULK SHEAR IS MORE REALISTICALLY AROUND 25 KTS. AS A RESULT...STRONG...BUT LIKELY UNORGANIZED ELEVATED CONVECTION IS POSSIBLE THIS MORNING. BASED ON THE RADAR PRESENTATION OF STORMS SO FAR EARLY THIS MORNING...CHANCES ARE NO LARGE HAIL WILL FALL ACROSS THE CWA...HOWEVER IF IT DOES OCCUR...HAIL WILL LIKELY BE CLOSE TO 1 INCH OR QUARTER SIZE IN DIAMETER. REMAINDER OF TODAY...THE 850 MB FRONT WILL SLIDE SOUTHEAST OF THE CWA BY LATE THIS MORNING...TAKING ALL THUNDERSTORM CHANCES SOUTHEAST OUT OF THE AREA IN ITS WAKE. RELATIVELY STRONG ISENTROPIC DOWNGLIDE/COLD AIR ADVECTION WILL DOMINATE THE LOWER TROPOSPHERE IN THE WAKE OF THIS FRONT. A STRONG UPPER LEVEL LOW PRESSURE SYSTEM WILL MOVE FROM WEST TO EAST OVER THE SOUTH PLAINS TODAY...WHICH WILL SPREAD SOME STRONG LARGE SCALE FORCING FOR ASCENT OVER THE CWA THIS AFTERNOON. HOWEVER...THE LARGE SCALE FORCING FOR ASCENT ASSOCIATED WITH THIS UPPER LOW IS NOT EXPECTED TO PENETRATE MUCH DEEPER THAN THE MIDDLE TROPOSPHERE TODAY BECAUSE THE MIDDLE TO LOW TROPOSPHERE WILL BE DEFINED BY HIGH STATIC STABILITY. A THERMODYNAMICALLY STABLE LAYER RESISTS VERTICAL MOTIONS...AND THEREFORE SHOULD PREVENT ANY ADDITIONAL PRECIPITATION FROM DEVELOPING OVER THE CWA TODAY ASSOCIATED WITH THIS UPPER LOW. THIS IS SUCH A STRONG UPPER TROUGH THAT IT WOULD BE A HUGE SURPRISE TO SEE SOME WEAK RADAR RETURNS DEVELOP OVER THE CWA EARLY THIS AFTERNOON...BUT THE COLD FRONT PUSHING THROUGH THE AREA JUST LOOKS TOO STRONG AND COLD TO ALLOW FOR MUCH LIFT TO OCCUR WHERE WE WOULD NEED IT TO GET RAIN SHOWERS...THAT BEING THE MID TO LOWER TROPOSPHERE. ASIDE FROM PRECIPITATION CONCERNS...BEHIND THE FRONT WE SHOULD JUST SEE STRONG NORTH WINDS AND COLD AIR ADVECTION THROUGHOUT THE DAY TODAY. TEMPERATURES ARE EXPECTED TO INCREASE INTO THE LOWER TO MID 50S BY LATE THIS AFTERNOON DESPITE THE STRONG COLD AIR ADVECTION AS SKIES CLEAR OUT RAPIDLY BEHIND THE PASSAGE OF THE UPPER TROUGH. EVEN THOUGH THE AIR BEHIND THE FRONT WILL REMAIN COLD...THE SUN ANGLE IS GETTING TOO HIGH FOR US NOT TO HEAT UP A BIT EVEN WITH JUST A FEW HOURS OF SUNSHINE. A WIND ADVISORY REMAINS IN EFFECT FOR THE ENTIRE AREA TODAY DUE TO NORTH WINDS OF 25 TO 30 MPH BEHIND THE FRONT. WINDS SHOULD DIMINISH AN HOUR OR TWO AFTER SUNSET AS HIGH PRESSURE BEGINS TO MOVE INTO THE REGION. TONIGHT...HIGH PRESSURE IS EXPECTED TO SLIDE SOUTH-SOUTHEAST ACROSS TEXAS FROM THE TX PANHANDLE TONIGHT. THIS WILL RESULT IN NEARLY CALM WINDS ACROSS WEST CENTRAL TEXAS...AND LIGHT NORTHERLY WINDS TO THE EAST. LIGHT WINDS AND CLEAR SKIES WILL MAKE FOR AN IDEAL RADIATIONAL COOLING ENVIRONMENT RESULTING IN TEMPERATURES FALLING INTO THE UPPER 20S TO MID 30S ACROSS THE CWA. YES...YOU READ THAT CORRECTLY...PARTS OF NORTH AND CENTRAL TEXAS ARE EXPECTED TO FALL BELOW FREEZING TONIGHT INTO TUESDAY MORNING. THIS IS PUSHING RECORD TERRITORY FOR A LATE FREEZE WHICH IS QUITE REMARKABLE CONSIDERING RECORDS HAVE BEEN KEPT SINCE THE LATE 1800S TO EARLY 1900S...SO WE ARE LOOKING AT AN EVENT THAT HAS A RETURN INTERVAL OF OVER 100 YEARS...FOR NORTH AND CENTRAL TEXAS AT LEAST. AS A RESULT...THIS FREEZE...ASSUMING IT OCCURS AS FORECAST...HAS THE POTENTIAL TO DO QUITE A BIT OF DAMAGE TO OUTDOOR PLANTS AS MOST FOLKS WOULD NOT HAVE WAITED THIS LONG TO GET THEIR SPRING PLANTING TAKEN CARE OF. AT ANY RATE...THIS IS WHY FREEZE WARNINGS ARE ISSUED...TO GIVE FOLKS A CHANCE TO PROTECT THEIR PLANTS. A FREEZE WARNING IS IN EFFECT FROM 1 AM TO 10 AM TONIGHT/TUESDAY MORNING FOR LOCATIONS ALONG AND NORTHWEST OF A LINE FROM SULPHUR SPRINGS TO KELLER TO WACO TO LAMPASAS. LOCATIONS JUST SOUTHEAST OF THIS LINE GENERALLY HAVE FORECAST LOWS AT 33 DEGREES...SO THIS WARNING MAY BE EXPANDED BASED ON HOW WARM WE GET THIS AFTERNOON AND BASED ON NEW MODEL GUIDANCE THROUGHOUT THE DAY. FORTUNATELY...MOST LOCATIONS IN THE FREEZE WARNING SHOULD SEE LOWS FALL JUST BELOW FREEZING...GENERALLY 30 TO 32 DEGREES. TEMPERATURES FALLING INTO THE UPPER 20S IS MORE LIKELY NORTH OF INTERSTATE 30...NEAR THE RED RIVER. TEMPERATURES ARE MORE LIKELY TO FALL BELOW FREEZING IN RURAL AREAS MORE SO THAN URBAN AREAS. THE URBAN HEAT ISLAND EFFECT WILL KEEP MOST OF THE CONCRETED AREAS OF THE METROPLEX ABOVE FREEZING. TARRANT COUNTY IS INCLUDED IN THE FREEZE WARNING ANYWAYS BECAUSE THE FAR NORTH AND WESTERN PORTIONS OF THE COUNTY...OUTSIDE OF THE 820 LOOP...ARE MORE LIKELY TO SEE FREEZING TEMPERATURES. TEMPERATURES ARE EXPECTED TO CLIMB ABOVE FREEZING AREA WIDE AFTER 10 AM TUESDAY MORNING. FROST IS POSSIBLE IN AREAS NOT INCLUDED IN THE FREEZE WARNING...SO EVEN IF YOU ARE NOT IN THE FREEZE WARNING AT THIS TIME...IT MAY BE PRUDENT TO PROTECT YOUR PLANTS ANYWAYS AS A PRECAUTION. THE AIR IS EXPECTED TO BE VERY DRY...SO WIDESPREAD FROST IS NOT LIKELY...BUT IT MAY BE BETTER TO BE SAFE THAN SORRY. REMAINDER OF THE FORECAST...WE WILL WARM UP AFTER TUESDAY...WITH NO MORE POTENTIAL FROSTS OR FREEZES IN THE FORECAST THROUGH NEXT WEEKEND. TUESDAY NIGHTS LOWS WILL BE WELL BELOW NORMAL AGAIN...BUT SHOULD FALL INTO THE MID TO UPPER 30S AT WORST. BY WEDNESDAY...SOUTH WINDS WILL HELP BRING DEW POINTS BACK UP INTO THE MID TO UPPER 40S...BRINGING ABOUT A RETURN TO MORE SEASONAL TEMPERATURES DURING THE DAYTIME AND OVERNIGHT. OUR NEXT CHANCE OF RAIN STILL LOOKS TO BE THURSDAY...ASSOCIATED WITH AN UPPER LEVEL TROUGH PROGGED TO MOVE OVER THE SOUTHERN PLAINS THURSDAY AFTERNOON. HOWEVER...THE ECMWF AND GFS BOTH KEEP THE BULK OF THE UPPER LEVEL FORCING FOR ASCENT ASSOCIATED WITH THIS TROUGH NORTH OF THE CWA. ASSUMING THIS VERIFIES...THIS DOES NOT USUALLY BODE WELL FOR PRECIPITATION CHANCES...EVEN WITH A WEAK COLD FRONT PUSHING SOUTHEAST ACROSS THE CWA THURSDAY AFTERNOON/EVENING. THE LOSS OF UPPER LEVEL DYNAMICS USUALLY MAKES PRECIPITATION ALONG COLD FRONTS ISOLATED AT BEST. THE CANADIAN IS FURTHER SOUTH WITH THIS UPPER TROUGH...AND THEREFORE HAS MUCH MORE PRECIPITATION FOR THE CWA. WILL CONTINUE TO MONITOR THE EVOLUTION OF THIS TROUGH IN FUTURE FORECASTS...HOWEVER FOR NOW JUST KEPT POPS IN THE 20 TO 30 PERCENT RANGE IN LINE WITH THE GFS/ECMWF SOLUTION. AFTER THURSDAY...OUR NEXT SHOT AT RAIN LOOKS TO BE SATURDAY NIGHT INTO SUNDAY...AS ALL GUIDANCE INDICATES AN UPPER LEVEL TROUGH WILL MOVE OVER THE SOUTHWESTERN CONUS AND TOWARDS NORTH TX AT THAT TIME. THE GFS IS THE MOST AGGRESSIVE WITH TAPPING INTO SOME TROPICAL PACIFIC MOISTURE IN THE UPPER TROPOSPHERE COURTESY OF THE SUB-TROPICAL JET. AS A RESULT THE GFS GIVES THE CWA A GOOD...WIDESPREAD ONE HALF TO ONE INCH OF RAINFALL FROM SATURDAY NIGHT THROUGH SUNDAY. WILL NOT BITE OFF ON THIS SOLUTION QUITE YET...BUT IT IS A GOOD SIGN THAT AT LEAST ALL MODELS HAVE SOME VERSION OF THIS TROUGH OVER THE SOUTHWESTERN CONUS. IF THIS CONSISTENT CONTINUES...POPS WILL BE INCREASED AREA WIDE FOR SATURDAY NIGHT INTO SUNDAY. THIS DOES NOT LOOK TO BE A GOOD SEVERE WEATHER SET UP FOR NOW...SO A GOOD WIDESPREAD RAINFALL WITH EMBEDDED THUNDERSTORMS IS WHAT IS EXPECTED AT THIS TIME. WE WILL SEE HOW THINGS CHANGE AS WE GET CLOSER TO NEXT WEEKEND OF COURSE. CAVANAUGH && .PRELIMINARY POINT TEMPS/POPS... DALLAS-FT. WORTH, TX 55 34 63 42 66 / 10 5 0 0 0 WACO, TX 56 33 63 36 67 / 20 0 0 0 0 PARIS, TX 51 30 59 36 64 / 20 5 0 0 0 DENTON, TX 53 29 62 38 66 / 10 5 0 0 0 MCKINNEY, TX 53 30 62 38 65 / 10 5 0 0 0 DALLAS, TX 56 35 63 42 66 / 10 5 0 0 0 TERRELL, TX 55 33 62 37 65 / 20 5 0 0 0 CORSICANA, TX 54 33 61 38 66 / 20 5 0 0 0 TEMPLE, TX 58 33 64 36 68 / 30 0 0 0 0 MINERAL WELLS, TX 55 32 63 37 69 / 10 0 0 0 0 && .FWD WATCHES/WARNINGS/ADVISORIES... FREEZE WARNING FROM 1 AM TO 10 AM CDT TUESDAY FOR TXZ091>095- 100>107-115>118-129>133-141>145-156-157-159. WIND ADVISORY UNTIL 9 PM CDT THIS EVENING FOR TXZ091>095-100>107- 115>123-129>135-141>148-156>162-174-175. && $$
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
417 AM CDT MON APR 14 2014 .DISCUSSION... 08Z SURFACE ANALYSIS INDICATED A STRONG COLD FRONT MOVING SOUTHEAST ACROSS THE CWA...LOCATED NEAR A LINE FROM ATHENS TO WACO TO LAMPASAS. JUST TO THE NORTHWEST OF THIS FRONT...A LINE OF SCATTERED SHOWERS AND THUNDERSTORMS WAS OBSERVED...LIKELY ASSOCIATED WITH THE 850 MB REFLECTION OF THE COLD FRONT. AT 0830Z...NONE OF THIS ACTIVITY WAS STRONG IN NATURE...AND AS ALLUDED TO ABOVE...IT IS ALL ELEVATED IN NATURE OVER THE FRONTAL INVERSION. REGIONAL SURFACE OBSERVATIONS INDICATE UNSEASONABLY COLD AIR BEHIND THE FRONT...WITH TEMPERATURES IN THE LOWER 40S LOCATED OVER WICHITA FALLS. NORTH WINDS WERE ALREADY RELATIVELY STRONG BEHIND THE FRONT...WITH MANY LOCATIONS OBSERVING WINDS IN THE 20 TO 25 MPH RANGE EARLY THIS MORNING. THIS MORNING...WENT AHEAD AND CANCELLED THE SEVERE THUNDERSTORM WATCH IN COORDINATION WITH THE SPC AND WFO SHV AS THE COLD FRONT HAD UNDERCUT ALL ONGOING CONVECTION. THIS DOES NOT MEAN IT/S IMPOSSIBLE TO GET STRONG STORMS THIS MORNING...HOWEVER THE ONLY STRONG TO MARGINALLY SEVERE STORM HAZARD ASSOCIATED WITH ELEVATED STORMS IS GOING TO BE IN THE FORM OF HAIL. RAP FORECAST SOUNDINGS INDICATE THE PRESENCE OF 1000-1500 J/KG OF MUCAPE AVAILABLE FOR THESE ELEVATED STORMS. DEEP LAYER SHEAR VALUES LOOK IMPRESSIVE...BUT ARE NOT REALLY RELEVANT FOR THIS ACTIVITY AS THE BULK OF THE CONTRIBUTION TO THE HIGHER SHEAR VALUES OCCURS BELOW THE FRONTAL INVERSION. DEEP LAYER BULK SHEAR CALCULATIONS INDICATE ABOUT 60 KTS OF SHEAR...WHILE EFFECTIVE BULK SHEAR IS MORE REALISTICALLY AROUND 25 KTS. AS A RESULT...STRONG...BUT LIKELY UNORGANIZED ELEVATED CONVECTION IS POSSIBLE THIS MORNING. BASED ON THE RADAR PRESENTATION OF STORMS SO FAR EARLY THIS MORNING...CHANCES ARE NO LARGE HAIL WILL FALL ACROSS THE CWA...HOWEVER IF IT DOES OCCUR...HAIL WILL LIKELY BE CLOSE TO 1 INCH OR QUARTER SIZE IN DIAMETER. REMAINDER OF TODAY...THE 850 MB FRONT WILL SLIDE SOUTHEAST OF THE CWA BY LATE THIS MORNING...TAKING ALL THUNDERSTORM CHANCES SOUTHEAST OUT OF THE AREA IN ITS WAKE. RELATIVELY STRONG ISENTROPIC DOWNGLIDE/COLD AIR ADVECTION WILL DOMINATE THE LOWER TROPOSPHERE IN THE WAKE OF THIS FRONT. A STRONG UPPER LEVEL LOW PRESSURE SYSTEM WILL MOVE FROM WEST TO EAST OVER THE SOUTH PLAINS TODAY...WHICH WILL SPREAD SOME STRONG LARGE SCALE FORCING FOR ASCENT OVER THE CWA THIS AFTERNOON. HOWEVER...THE LARGE SCALE FORCING FOR ASCENT ASSOCIATED WITH THIS UPPER LOW IS NOT EXPECTED TO PENETRATE MUCH DEEPER THAN THE MIDDLE TROPOSPHERE TODAY BECAUSE THE MIDDLE TO LOW TROPOSPHERE WILL BE DEFINED BY HIGH STATIC STABILITY. A THERMODYNAMICALLY STABLE LAYER RESISTS VERTICAL MOTIONS...AND THEREFORE SHOULD PREVENT ANY ADDITIONAL PRECIPITATION FROM DEVELOPING OVER THE CWA TODAY ASSOCIATED WITH THIS UPPER LOW. THIS IS SUCH A STRONG UPPER TROUGH THAT IT WOULD BE A HUGE SURPRISE TO SEE SOME WEAK RADAR RETURNS DEVELOP OVER THE CWA EARLY THIS AFTERNOON...BUT THE COLD FRONT PUSHING THROUGH THE AREA JUST LOOKS TOO STRONG AND COLD TO ALLOW FOR MUCH LIFT TO OCCUR WHERE WE WOULD NEED IT TO GET RAIN SHOWERS...THAT BEING THE MID TO LOWER TROPOSPHERE. ASIDE FROM PRECIPITATION CONCERNS...BEHIND THE FRONT WE SHOULD JUST SEE STRONG NORTH WINDS AND COLD AIR ADVECTION THROUGHOUT THE DAY TODAY. TEMPERATURES ARE EXPECTED TO INCREASE INTO THE LOWER TO MID 50S BY LATE THIS AFTERNOON DESPITE THE STRONG COLD AIR ADVECTION AS SKIES CLEAR OUT RAPIDLY BEHIND THE PASSAGE OF THE UPPER TROUGH. EVEN THOUGH THE AIR BEHIND THE FRONT WILL REMAIN COLD...THE SUN ANGLE IS GETTING TOO HIGH FOR US NOT TO HEAT UP A BIT EVEN WITH JUST A FEW HOURS OF SUNSHINE. A WIND ADVISORY REMAINS IN EFFECT FOR THE ENTIRE AREA TODAY DUE TO NORTH WINDS OF 25 TO 30 MPH BEHIND THE FRONT. WINDS SHOULD DIMINISH AN HOUR OR TWO AFTER SUNSET AS HIGH PRESSURE BEGINS TO MOVE INTO THE REGION. TONIGHT...HIGH PRESSURE IS EXPECTED TO SLIDE SOUTH-SOUTHEAST ACROSS TEXAS FROM THE TX PANHANDLE TONIGHT. THIS WILL RESULT IN NEARLY CALM WINDS ACROSS WEST CENTRAL TEXAS...AND LIGHT NORTHERLY WINDS TO THE EAST. LIGHT WINDS AND CLEAR SKIES WILL MAKE FOR AN IDEAL RADIATIONAL COOLING ENVIRONMENT RESULTING IN TEMPERATURES FALLING INTO THE UPPER 20S TO MID 30S ACROSS THE CWA. YES...YOU READ THAT CORRECTLY...PARTS OF NORTH AND CENTRAL TEXAS ARE EXPECTED TO FALL BELOW FREEZING TONIGHT INTO TUESDAY MORNING. THIS IS PUSHING RECORD TERRITORY FOR A LATE FREEZE WHICH IS QUITE REMARKABLE CONSIDERING RECORDS HAVE BEEN KEPT SINCE THE LATE 1800S TO EARLY 1900S...SO WE ARE LOOKING AT AN EVENT THAT HAS A RETURN INTERVAL OF OVER 100 YEARS...FOR NORTH AND CENTRAL TEXAS AT LEAST. AS A RESULT...THIS FREEZE...ASSUMING IT OCCURS AS FORECAST...HAS THE POTENTIAL TO DO QUITE A BIT OF DAMAGE TO OUTDOOR PLANTS AS MOST FOLKS WOULD NOT HAVE WAITED THIS LONG TO GET THEIR SPRING PLANTING TAKEN CARE OF. AT ANY RATE...THIS IS WHY FREEZE WARNINGS ARE ISSUED...TO GIVE FOLKS A CHANCE TO PROTECT THEIR PLANTS. A FREEZE WARNING IS IN EFFECT FROM 1 AM TO 10 AM TONIGHT/TUESDAY MORNING FOR LOCATIONS ALONG AND NORTHWEST OF A LINE FROM SULPHUR SPRINGS TO KELLER TO WACO TO LAMPASAS. LOCATIONS JUST SOUTHEAST OF THIS LINE GENERALLY HAVE FORECAST LOWS AT 33 DEGREES...SO THIS WARNING MAY BE EXPANDED BASED ON HOW WARM WE GET THIS AFTERNOON AND BASED ON NEW MODEL GUIDANCE THROUGHOUT THE DAY. FORTUNATELY...MOST LOCATIONS IN THE FREEZE WARNING SHOULD SEE LOWS FALL JUST BELOW FREEZING...GENERALLY 30 TO 32 DEGREES. TEMPERATURES FALLING INTO THE UPPER 20S IS MORE LIKELY NORTH OF INTERSTATE 30...NEAR THE RED RIVER. TEMPERATURES ARE MORE LIKELY TO FALL BELOW FREEZING IN RURAL AREAS MORE SO THAN URBAN AREAS. THE URBAN HEAT ISLAND EFFECT WILL KEEP MOST OF THE CONCRETED AREAS OF THE METROPLEX ABOVE FREEZING. TARRANT COUNTY IS INCLUDED IN THE FREEZE WARNING ANYWAYS BECAUSE THE FAR NORTH AND WESTERN PORTIONS OF THE COUNTY...OUTSIDE OF THE 820 LOOP...ARE MORE LIKELY TO SEE FREEZING TEMPERATURES. TEMPERATURES ARE EXPECTED TO CLIMB ABOVE FREEZING AREA WIDE AFTER 10 AM TUESDAY MORNING. FROST IS POSSIBLE IN AREAS NOT INCLUDED IN THE FREEZE WARNING...SO EVEN IF YOU ARE NOT IN THE FREEZE WARNING AT THIS TIME...IT MAY BE PRUDENT TO PROTECT YOUR PLANTS ANYWAYS AS A PRECAUTION. THE AIR IS EXPECTED TO BE VERY DRY...SO WIDESPREAD FROST IS NOT LIKELY...BUT IT MAY BE BETTER TO BE SAFE THAN SORRY. REMAINDER OF THE FORECAST...WE WILL WARM UP AFTER TUESDAY...WITH NO MORE POTENTIAL FROSTS OR FREEZES IN THE FORECAST THROUGH NEXT WEEKEND. TUESDAY NIGHTS LOWS WILL BE WELL BELOW NORMAL AGAIN...BUT SHOULD FALL INTO THE MID TO UPPER 30S AT WORST. BY WEDNESDAY...SOUTH WINDS WILL HELP BRING DEW POINTS BACK UP INTO THE MID TO UPPER 40S...BRINGING ABOUT A RETURN TO MORE SEASONAL TEMPERATURES DURING THE DAYTIME AND OVERNIGHT. OUR NEXT CHANCE OF RAIN STILL LOOKS TO BE THURSDAY...ASSOCIATED WITH AN UPPER LEVEL TROUGH PROGGED TO MOVE OVER THE SOUTHERN PLAINS THURSDAY AFTERNOON. HOWEVER...THE ECMWF AND GFS BOTH KEEP THE BULK OF THE UPPER LEVEL FORCING FOR ASCENT ASSOCIATED WITH THIS TROUGH NORTH OF THE CWA. ASSUMING THIS VERIFIES...THIS DOES NOT USUALLY BODE WELL FOR PRECIPITATION CHANCES...EVEN WITH A WEAK COLD FRONT PUSHING SOUTHEAST ACROSS THE CWA THURSDAY AFTERNOON/EVENING. THE LOSS OF UPPER LEVEL DYNAMICS USUALLY MAKES PRECIPITATION ALONG COLD FRONTS ISOLATED AT BEST. THE CANADIAN IS FURTHER SOUTH WITH THIS UPPER TROUGH...AND THEREFORE HAS MUCH MORE PRECIPITATION FOR THE CWA. WILL CONTINUE TO MONITOR THE EVOLUTION OF THIS TROUGH IN FUTURE FORECASTS...HOWEVER FOR NOW JUST KEPT POPS IN THE 20 TO 30 PERCENT RANGE IN LINE WITH THE GFS/ECMWF SOLUTION. AFTER THURSDAY...OUR NEXT SHOT AT RAIN LOOKS TO BE SATURDAY NIGHT INTO SUNDAY...AS ALL GUIDANCE INDICATES AN UPPER LEVEL TROUGH WILL MOVE OVER THE SOUTHWESTERN CONUS AND TOWARDS NORTH TX AT THAT TIME. THE GFS IS THE MOST AGGRESSIVE WITH TAPPING INTO SOME TROPICAL PACIFIC MOISTURE IN THE UPPER TROPOSPHERE COURTESY OF THE SUB-TROPICAL JET. AS A RESULT THE GFS GIVES THE CWA A GOOD...WIDESPREAD ONE HALF TO ONE INCH OF RAINFALL FROM SATURDAY NIGHT THROUGH SUNDAY. WILL NOT BITE OFF ON THIS SOLUTION QUITE YET...BUT IT IS A GOOD SIGN THAT AT LEAST ALL MODELS HAVE SOME VERSION OF THIS TROUGH OVER THE SOUTHWESTERN CONUS. IF THIS CONSISTENT CONTINUES...POPS WILL BE INCREASED AREA WIDE FOR SATURDAY NIGHT INTO SUNDAY. THIS DOES NOT LOOK TO BE A GOOD SEVERE WEATHER SET UP FOR NOW...SO A GOOD WIDESPREAD RAINFALL WITH EMBEDDED THUNDERSTORMS IS WHAT IS EXPECTED AT THIS TIME. WE WILL SEE HOW THINGS CHANGE AS WE GET CLOSER TO NEXT WEEKEND OF COURSE. CAVANAUGH && .PRELIMINARY POINT TEMPS/POPS... DALLAS-FT. WORTH, TX 55 34 63 42 66 / 10 5 0 0 0 WACO, TX 56 33 63 36 67 / 20 0 0 0 0 PARIS, TX 51 30 59 36 64 / 20 5 0 0 0 DENTON, TX 53 29 62 38 66 / 10 5 0 0 0 MCKINNEY, TX 53 30 62 38 65 / 10 5 0 0 0 DALLAS, TX 56 35 63 42 66 / 10 5 0 0 0 TERRELL, TX 55 33 62 37 65 / 20 5 0 0 0 CORSICANA, TX 54 33 61 38 66 / 20 5 0 0 0 TEMPLE, TX 58 33 64 36 68 / 30 0 0 0 0 MINERAL WELLS, TX 55 32 63 37 69 / 10 0 0 0 0 && .FWD WATCHES/WARNINGS/ADVISORIES... FREEZE WARNING FROM 1 AM TO 10 AM CDT TUESDAY FOR TXZ091>095- 100>107-115>118-129>133-141>145-156-157-159. WIND ADVISORY FROM 9 AM THIS MORNING TO 9 PM CDT THIS EVENING FOR TXZ091>095-100>107-115>123-129>135-141>148-156>162-174-175. && $$ /
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
140 PM EDT MON APR 14 2014 .SYNOPSIS... A COLD FRONT FROM THE GREAT LAKES TO SE TX WILL SHIFT EAST TODAY AND TONIGHT CROSSING THE MID ATLANTIC REGION ON TUESDAY. BEHIND THE FRONT HIGH PRESSURE WILL BUILD IN FOR WEDNESDAY THROUGH FRIDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 105 PM EDT MONDAY... UPDATED FORECAST TO REFLECT RADAR TRENDS AND HRRR APPEARS TO HANDLE THINGS WELL IN THE NEAR TERM. THIS MEANS LESS THREAT OF RAIN SHOWERS OVER THE AREA...THEN SHOWERS INCREASE BY AFTER 3-5PM AHEAD OF VORT OVER NRN GA EARLY. THUNDER SITUATION STILL MARGINAL BUT ENOUGH INSTABILITY IN THE MID LEVELS FOR ISOLATED THREAT MAINLY SOUTHEAST AND SOUTHWEST CWA. PREVIOUS VALID DISCUSSION... CUT HIGH TEMPS BACK A FEW DEGREES ACROSS THE MOUNTAINS PER LACK OF SUN AND SHOWERS MOVING IN. MUCH BETTER SYNOPTIC SCALE LIFT AFTER 00Z/8PM THIS EVENING. AS THE COLD FRONT APPROACHES LATE TONIGHT...SURFACE AND LOW LEVEL WINDS BACK...ADDING THE SOUTHEAST UPSLOPE COMPONENT TO THE STRONG FORCING. LARGEST PRECIPITATION AMOUNTS WILL BE AFTER MIDNIGHT. FRONT DOES NOT REACH THE FAR WESTERN PART OF THE FORECAST AREA BEFORE 12Z/8AM. STAYED CLOSER TO THE WARMER GUIDANCE FOR OVERNIGHT LOWS. THE LOW LEVEL JET INCREASES OVERNIGHT. HIGHER ELEVATIONS MAY HAVE GUSTS OF 25 TO 30 MPH. && .SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/... AS OF 400 AM EDT MONDAY... A STRONG COLD FRONT WILL MAKE ITS WAY ACROSS THE FORECAST AREA BEGINNING TUESDAY MORNING...AND THEREFORE WILL HAVE SEVERAL THINGS TO KEEP AN EYE. MODELS CONTINUE TO INDICATE A SOUTHWESTERLY 55KT LOW LEVEL JET DEVELOPING AHEAD OF THE FRONT. INSTABILITY AHEAD OF THE FRONT WILL BE MARGINAL...RESULTING IN MAINLY HEAVY SHOWER ACTIVITY WITH ONLY ISOLATED THUNDER AS THE FRONT PASSES. HOWEVER...WITH THE JET BLOWING JUST OFF THE SURFACE OVER THE MOUNTAINS...WOULD NOT BE SURPRISED TO SEE SOME OF THE MORE INTENSE SHOWER ACTIVITY DRAW THE STRONGER WINDS DOWN TO THE GROUND LEVEL. HIGH PRESSURE WILL BUILD IN QUICKLY AFTER THE COLD FRONT PASSES... RESULTING IN A ROUGHLY 10MB PRESSURE GRADIENT ACROSS THE FORECAST AREA FROM MID AFTERNOON THROUGH ALMOST MIDNIGHT. EXPECT STRONG NORTHWEST WINDS WITH 40 TO 50 MPH GUSTS ACROSS THE MOUNTAINS...WITH THE STRONGEST GUSTS FOUND ALONG THE BLUE RIDGE PARKWAY SOUTH OF ROANOKE. THESE GUSTS...WHEN COMBINED WITH PROLONGED RAINFALL...WILL LIKELY BE ENOUGH TO BRING DOWN A FEW TREES...AND RESULT IN LOCALIZED POWER OUTAGES. RAINFALL WILL BE WIDESPREAD AND HEAVY AT TIMES...WITH A STORM TOTAL AMOUNT OF OVER AN INCH FOR THE ENTIRE FORECAST AREA...WITH AROUND 2 INCHES EXPECTED ALONG THE BLUE RIDGE. MAY SEE LOCALIZED MINOR FLOODING ISSUES DEVELOP WHERE BANDS OF HEAVY RAIN PASS REPEATEDLY OVER THE SAME LOCATIONS. RAINFALL MAY ALSO PUSH SOME RIVERS TO BANKFULL OR MINOR FLOOD LATER IN THE WEEK. FOR THE FIRST FEW HOURS AFTER FRONTAL PASSAGE...TEMPERATURES WILL PLUMMET AT A RATE OF 6 TO 9 DEGREES PER HOUR. EXPECT TEMPERATURES TO APPROACH FREEZING FROM SOUTHEAST WEST VIRGINIA THROUGH THE NORTH CAROLINA MOUNTAINS BY EARLY EVENING...ALLOWING RAIN SHOWERS TO CHANGE OVER TO SNOW. WHILE WARM GROUND TEMPERATURES WILL CAUSE SNOW TO MELT ON CONTACT ACROSS MANY AREAS...MAY SEE UP TO A HALF INCH OF SNOW ACCUMULATE ALONG OUR MORE PROMINENT WEST FACING SLOPES BEFORE SNOW SHOWERS END OFF SHORTLY AFTER MIDNIGHT WEDNESDAY. NEXT WE GET TO DEAL WITH SUB FREEZING TEMPERATURES AREAWIDE BY SUNRISE WEDNESDAY. EXPECT OVERNIGHT LOWS TO RANGE FROM THE MID 20S ACROSS SOUTHEAST WEST VIRGINIA TO THE LOW 30S ACROSS THE SOUTHSIDE. PRECAUTIONS SHOULD BE TAKEN TO PROTECT ANY PLANTS THAT MAY BE KILLED BY FREEZING TEMPERATURES. HIGH PRESSURE WILL PASS FROM THE GREAT LAKES TO NEW ENGLAND ON WEDNESDAY...AND WILL BUILD SOUTHWARD ALONG THE EASTERN FACE OF THE APPALACHIANS. THE NORTHEASTERLY WIND FLOW AROUND THE HIGH WILL KEEP COOL CONDITIONS IN PLACE HEADING INTO THE SECOND HALF OF THE WORKWEEK...WITH FREEZING TEMPERATURES LIKELY AGAIN WEDNESDAY NIGHT. A GRADUAL WARM UP WILL TAKE PLACE THURSDAY AS WINDS ALOFT BEGIN TO SHIFT SOUTHWESTERLY AGAIN. && .LONG TERM /FRIDAY THROUGH SUNDAY/... AS OF 200 PM EDT SATURDAY... EXPECT HIGH PRESSURE TO REMAIN IN CONTROL OF THE WEATHER PATTERN FOR FRIDAY. A COLD FRONT WILL APPROACH FROM THE WEST FRIDAY NIGHT INTO SATURDAY. GENERALLY FOLLOWED WPCGUIDE FOR POPS. STILL LOOKS LIKE THE BEST CHANCE FOR WIDESPREAD RAIN WILL OCCUR ON FRIDAY NIGHT INTO SATURDAY. LEANED TOWARDS THE ECENS MEAN WITH HANDLING THE SOUTHERN STREAM SYSTEM AND ITS MOISTURE. TEMPERATURES MODERATE TOWARD NEXT WEEKEND CLOSER TO NORMAL. && .AVIATION /18Z MONDAY THROUGH SATURDAY/... AS OF 130 PM EDT MONDAY... VFR CIGS THIS AFTERNOON WILL SINK TO MVFR THEN IFR THIS EVENING WITH INCREASING THREAT OF SHOWERS. VSBYS IN THE HEAVIER SHOWERS SHOULD DROP TO HIGH END IFR/LOW END MVFR. A TSRA IS POSSIBLE BUT NOT ENOUGH COVERAGE/THREAT OVERALL TO HAVE IN TAFS. GUSTY SOUTH WINDS THIS AFTERNOON SHOULD WEAKEN THIS EVENING. OVERNIGHT...FRONT WILL APPROACH THE WEST AND FINALLY EXIT EAST OF THE MTNS BY 15Z TUESDAY...AND OUT EAST IN THE AFTERNOON. WILL SEE MODERATE SHOWERS AND AT TIMES HEAVIER DOWNPOURS. ON AVERAGE VSBYS/CIGS WILL BE IN IFR/MVFR. ONCE FRONT PASSES THE BLF AREA SHOULD SEE LOWER CIGS UPSLOPE EFFECT...AND INTO LWB AS WELL WITH BUFKIT SOUNDINGS AND GUIDANCE SUGGESTING CIGS BELOW 5H FEET. EXPECT RAINS AND SOME THUNDER TO LINGER EAST OF THE BLUE RIDGE INTO TUESDAY EVENING. COLDER AIR WILL BRING TEMPS DOWN FAST IN THE MOUNTAINS BY TUESDAY EVENING WHERE SOME SNOW SHOWERS ARE POSSIBLE. WINDS TO BE AN ISSUE AS WELL BEHIND FRONT TUESDAY INTO TUESDAY NIGHT WITH GUSTS TO 40 KNOTS POSSIBLE. SMALL WINDOW AS HIGH PRESSURE BUILDS IN WEDNESDAY MORNING. MAY SEE RESIDUAL MOISTURE WEDNESDAY KEEPING MVFR CIGS OVER THE MOUNTAINS. VFR THEN EXPECTED THURSDAY WITH HIGH PRESSURE RIDGING IN FROM OFF NEW ENGLAND BETWEEN THE EXITING FRONT OFFSHORE AND THE NEXT COLD FRONT TO THE NW. NEXT COLD FRONT APPROACHES FROM THE WEST FRIDAY BUT APPEARS SLOW ENOUGH TO MAINTAIN VFR DURING THE DAY FOR NOW. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...AMS/WP NEAR TERM...AMS/WP SHORT TERM...NF LONG TERM...KK AVIATION...WP
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1010 AM EDT MON APR 14 2014 .SYNOPSIS... A COLD FRONT FROM THE GREAT LAKES TO SE TX WILL SHIFT EAST TODAY AND TONIGHT CROSSING THE MID ATLANTIC REGION ON TUESDAY. BEHIND THE FRONT HIGH PRESSURE WILL BUILD IN FOR WEDNESDAY THROUGH FRIDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 955 AM EDT MONDAY... RADAR SHOWING VERY LIGHT RETURNS OVER NE TN/FAR SW VA AND NW NC. REGIONAL RADAR SHOWS STRONG CONVECTION ACROSS ALABAMA INTO MS WITH LIGHT TO MODERATE SHOWERS OVER EAST-CENTRAL TN INTO CENTRAL KY. 12Z SOUNDING INDICATES MID LEVEL LAPSE RATES OF 7.5C/KM. THE STORM PREDICTION CENTER HAS EXPANDED THEIR GENERAL THUNDERSTORM RISK TO COVER THE ENTIRE CWA. NOT IMPRESSED WITH THUNDER CHANCES GIVEN EXTENSIVE CLOUDS IN PLACE BUT ASSOCIATED SHORTWAVE WITH THE CONVECTION IN ALABAMA IS PROGGED TO SHIFT INTO NC LATE THIS AFTERNOON. PER LATEST HRRR WHICH IS HANDLING SHOWERS OR LACK THEREOF OUT THERE NOW...WILL BACK OFF ON HIGHER POPS FOR ABOUT 1-2 HOURS IN THE WEST UNTIL AFTER 19Z/3PM. WILL HAVE ISOLATED THUNDER IN THE FORECAST THIS AFTERNOON...WITH SOME LIMITED INSTABILITY. CUT HIGH TEMPS BACK A FEW DEGREES ACROSS THE MOUNTAINS PER LACK OF SUN AND SHOWERS MOVING IN. PREVIOUS VALID DISCUSSION... MUCH BETTER SYNOPTIC SCALE LIFT AFTER 00Z/8PM THIS EVENING. AS THE COLD FRONT APPROACHES LATE TONIGHT...SURFACE AND LOW LEVEL WINDS BACK...ADDING THE SOUTHEAST UPSLOPE COMPONENT TO THE STRONG FORCING. LARGEST PRECIPITATION AMOUNTS WILL BE AFTER MIDNIGHT. FRONT DOES NOT REACH THE FAR WESTERN PART OF THE FORECAST AREA BEFORE 12Z/8AM. STAYED CLOSER TO THE WARMER GUIDANCE FOR OVERNIGHT LOWS. THE LOW LEVEL JET INCREASES OVERNIGHT. HIGHER ELEVATIONS MAY HAVE GUSTS OF 25 TO 30 MPH. && .SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/... AS OF 400 AM EDT MONDAY... A STRONG COLD FRONT WILL MAKE ITS WAY ACROSS THE FORECAST AREA BEGINNING TUESDAY MORNING...AND THEREFORE WILL HAVE SEVERAL THINGS TO KEEP AN EYE. MODELS CONTINUE TO INDICATE A SOUTHWESTERLY 55KT LOW LEVEL JET DEVELOPING AHEAD OF THE FRONT. INSTABILITY AHEAD OF THE FRONT WILL BE MARGINAL...RESULTING IN MAINLY HEAVY SHOWER ACTIVITY WITH ONLY ISOLATED THUNDER AS THE FRONT PASSES. HOWEVER...WITH THE JET BLOWING JUST OFF THE SURFACE OVER THE MOUNTAINS...WOULD NOT BE SURPRISED TO SEE SOME OF THE MORE INTENSE SHOWER ACTIVITY DRAW THE STRONGER WINDS DOWN TO THE GROUND LEVEL. HIGH PRESSURE WILL BUILD IN QUICKLY AFTER THE COLD FRONT PASSES... RESULTING IN A ROUGHLY 10MB PRESSURE GRADIENT ACROSS THE FORECAST AREA FROM MID AFTERNOON THROUGH ALMOST MIDNIGHT. EXPECT STRONG NORTHWEST WINDS WITH 40 TO 50 MPH GUSTS ACROSS THE MOUNTAINS...WITH THE STRONGEST GUSTS FOUND ALONG THE BLUE RIDGE PARKWAY SOUTH OF ROANOKE. THESE GUSTS...WHEN COMBINED WITH PROLONGED RAINFALL...WILL LIKELY BE ENOUGH TO BRING DOWN A FEW TREES...AND RESULT IN LOCALIZED POWER OUTAGES. RAINFALL WILL BE WIDESPREAD AND HEAVY AT TIMES...WITH A STORM TOTAL AMOUNT OF OVER AN INCH FOR THE ENTIRE FORECAST AREA...WITH AROUND 2 INCHES EXPECTED ALONG THE BLUE RIDGE. MAY SEE LOCALIZED MINOR FLOODING ISSUES DEVELOP WHERE BANDS OF HEAVY RAIN PASS REPEATEDLY OVER THE SAME LOCATIONS. RAINFALL MAY ALSO PUSH SOME RIVERS TO BANKFULL OR MINOR FLOOD LATER IN THE WEEK. FOR THE FIRST FEW HOURS AFTER FRONTAL PASSAGE...TEMPERATURES WILL PLUMMET AT A RATE OF 6 TO 9 DEGREES PER HOUR. EXPECT TEMPERATURES TO APPROACH FREEZING FROM SOUTHEAST WEST VIRGINIA THROUGH THE NORTH CAROLINA MOUNTAINS BY EARLY EVENING...ALLOWING RAIN SHOWERS TO CHANGE OVER TO SNOW. WHILE WARM GROUND TEMPERATURES WILL CAUSE SNOW TO MELT ON CONTACT ACROSS MANY AREAS...MAY SEE UP TO A HALF INCH OF SNOW ACCUMULATE ALONG OUR MORE PROMINENT WEST FACING SLOPES BEFORE SNOW SHOWERS END OFF SHORTLY AFTER MIDNIGHT WEDNESDAY. NEXT WE GET TO DEAL WITH SUB FREEZING TEMPERATURES AREAWIDE BY SUNRISE WEDNESDAY. EXPECT OVERNIGHT LOWS TO RANGE FROM THE MID 20S ACROSS SOUTHEAST WEST VIRGINIA TO THE LOW 30S ACROSS THE SOUTHSIDE. PRECAUTIONS SHOULD BE TAKEN TO PROTECT ANY PLANTS THAT MAY BE KILLED BY FREEZING TEMPERATURES. HIGH PRESSURE WILL PASS FROM THE GREAT LAKES TO NEW ENGLAND ON WEDNESDAY...AND WILL BUILD SOUTHWARD ALONG THE EASTERN FACE OF THE APPALACHIANS. THE NORTHEASTERLY WIND FLOW AROUND THE HIGH WILL KEEP COOL CONDITIONS IN PLACE HEADING INTO THE SECOND HALF OF THE WORKWEEK...WITH FREEZING TEMPERATURES LIKELY AGAIN WEDNESDAY NIGHT. A GRADUAL WARM UP WILL TAKE PLACE THURSDAY AS WINDS ALOFT BEGIN TO SHIFT SOUTHWESTERLY AGAIN. && .LONG TERM /FRIDAY THROUGH SUNDAY/... AS OF 200 PM EDT SATURDAY... EXPECT HIGH PRESSURE TO REMAIN IN CONTROL OF THE WEATHER PATTERN FOR FRIDAY. A COLD FRONT WILL APPROACH FROM THE WEST FRIDAY NIGHT INTO SATURDAY. GENERALLY FOLLOWED WPCGUIDE FOR POPS. STILL LOOKS LIKE THE BEST CHANCE FOR WIDESPREAD RAIN WILL OCCUR ON FRIDAY NIGHT INTO SATURDAY. LEANED TOWARDS THE ECENS MEAN WITH HANDLING THE SOUTHERN STREAM SYSTEM AND ITS MOISTURE. TEMPERATURES MODERATE TOWARD NEXT WEEKEND CLOSER TO NORMAL. && .AVIATION /14Z MONDAY THROUGH FRIDAY/... AS OF 130 AM EDT MONDAY... MVFR CEILINGS HAD FILLED IN OVER THE SOUTHERN APPALACHIANS THIS MORNING. EXPECTING KDAN AND KROA TO GO IN AND OUT OF MVFR CLOUDS THROUGH 15Z/11AM. MODELS BRING THE SHORT WAVE OVER THE TENNESSEE VALLEY ACROSS THE REGION MAINLY BETWEEN 15Z/11AM AND 21Z/5PM. WITH ALL THE CLOUD COVER DURING THE DAY...THERE WILL BE ONLY A LIMITED THREAT OF ANY THUNDER. MODERATE CONFIDENCE THAT VISIBILITIES WILL REMAIN VFR AND NOT LOWER AS THESE SHOWERS MOVE THROUGH. THE STRONG COLD FRONT WILL ARRIVE IN THE MOUNTAINS AFTER 05Z/1AM TUESDAY. THIS RAIN WILL RESULT IN WIDESPREAD IFR TO MVFR CEILINGS AND VISIBILITIES. THE RAIN MAY BE HEAVY AT TIMES. LOOKS WET THRU TUESDAY NIGHT. STRONG GUSTY NW WINDS ARE LIKELY BEHIND THE FRONT TUESDAY AFTERNOON AND NIGHT. DRIER AIR WORKS IN BEHIND THE SYSTEM FOR WEDNESDAY ALTHOUGH RESIDUAL MOISTURE AND COLD AIR ALOFT MAY ACT TO KEEP MVFR CIGS OVER THE MOUNTAINS ON TUESDAY NIGHT. VFR THEN EXPECTED THURSDAY WITH HIGH PRESSURE RIDGING IN FROM OFF NEW ENGLAND BETWEEN THE EXITING FRONT OFFSHORE AND THE NEXT COLD FRONT TO THE NW. NEXT COLD FRONT APPROACHES FROM THE WEST FRIDAY BUT APPEARS SLOW ENOUGH TO MAINTAIN VFR DURING THE DAY FOR NOW. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...AMS/WP NEAR TERM...AMS/WP SHORT TERM...NF LONG TERM...KK AVIATION...AMS/JH
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
735 AM EDT MON APR 14 2014 .SYNOPSIS... LOW PRESSURE WAS OVER ILLINOIS WITH A COLD FRONT TRAILING FROM THE LOW INTO TEXAS. THIS FRONT WILL MOVE EAST TODAY AND TONIGHT AND WILL CROSS THE MID ATLANTIC REGION ON TUESDAY. BEHIND THE FRONT HIGH PRESSURE WILL BUILD IN FOR WEDNESDAY THROUGH FRIDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 415 AM EDT MONDAY... WATER VAPOR LOOP SHOWED A WELL DEFINED SHORT WAVE CROSSING THROUGH THE TENNESSE VALLEY. THICK CLOUD COVER WAS ALREADY SPREADING INTO THE COUNTY WARNING AREA FROM THE WEST. SHORT RANGE MODELS INCLUDING THE LATEST RUC/WRF AND HRRR BRING THE PRECIPITATION ASSOCIATED WITH THIS WAVE INTO THE WESTERN COUNTY WARNING AREA BETWEEN 15Z/11AM AND 18Z/2PM. WITH ALL THE CLOUD COVER DO NOT EXPECT MUCH INSTABILITY. BUFKIT OFF THE NAM AND GFS SHOWED LOW CAPE VALUES TODAY. HELD PROBABILITY OF THUNDER TO SLIGHT CHANCE. DO EXPECT ISOLATED TO SCATTERED SHOWERS AHEAD OF THE TENNESSEE VALLEY SHORT WAVE...WITH THE BETTER AREAL COVERAGE IN THE MOUNTAINS THROUGH NOON. HIGH TODAY WILL STILL BE ABOVE NORMAL BUT ONLY A SMALL RISE FROM THE CURRENT MILD TEMPERATURES. MUCH BETTER SYNOPTIC SCALE LIFT AFTER 00Z/8PM THIS EVENING. AS THE COLD FRONT APPROACHES LATE TONIGHT...SURFACE AND LOW LEVEL WINDS BACK...ADDING THE SOUTHEAST UPSLOPE COMPONENT TO THE STRONG FORCING. LARGEST PRECIPITATION AMOUNTS WILL BE AFTER MIDNIGHT. FRONT DOES NOT REACH THE FAR WESTERN PART OF THE FORECAST AREA BEFORE 12Z/8AM. STAYED CLOSER TO THE WARMER GUIDANCE FOR OVERNIGHT LOWS. THE LOW LEVEL JET INCREASES OVERNIGHT. HIGHER ELEVATIONS MAY HAVE GUSTS OF 25 TO 30 MPH. && .SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/... AS OF 400 AM EDT MONDAY... A STRONG COLD FRONT WILL MAKE ITS WAY ACROSS THE FORECAST AREA BEGINNING TUESDAY MORNING...AND THEREFORE WILL HAVE SEVERAL THINGS TO KEEP AN EYE. MODELS CONTINUE TO INDICATE A SOUTHWESTERLY 55KT LOW LEVEL JET DEVELOPING AHEAD OF THE FRONT. INSTABILITY AHEAD OF THE FRONT WILL BE MARGINAL...RESULTING IN MAINLY HEAVY SHOWER ACTIVITY WITH ONLY ISOLATED THUNDER AS THE FRONT PASSES. HOWEVER...WITH THE JET BLOWING JUST OFF THE SURFACE OVER THE MOUNTAINS...WOULD NOT BE SURPRISED TO SEE SOME OF THE MORE INTENSE SHOWER ACTIVITY DRAW THE STRONGER WINDS DOWN TO THE GROUND LEVEL. HIGH PRESSURE WILL BUILD IN QUICKLY AFTER THE COLD FRONT PASSES... RESULTING IN A ROUGHLY 10MB PRESSURE GRADIENT ACROSS THE FORECAST AREA FROM MID AFTERNOON THROUGH ALMOST MIDNIGHT. EXPECT STRONG NORTHWEST WINDS WITH 40 TO 50 MPH GUSTS ACROSS THE MOUNTAINS...WITH THE STRONGEST GUSTS FOUND ALONG THE BLUE RIDGE PARKWAY SOUTH OF ROANOKE. THESE GUSTS...WHEN COMBINED WITH PROLONGED RAINFALL...WILL LIKELY BE ENOUGH TO BRING DOWN A FEW TREES...AND RESULT IN LOCALIZED POWER OUTAGES. RAINFALL WILL BE WIDESPREAD AND HEAVY AT TIMES...WITH A STORM TOTAL AMOUNT OF OVER AN INCH FOR THE ENTIRE FORECAST AREA...WITH AROUND 2 INCHES EXPECTED ALONG THE BLUE RIDGE. MAY SEE LOCALIZED MINOR FLOODING ISSUES DEVELOP WHERE BANDS OF HEAVY RAIN PASS REPEATEDLY OVER THE SAME LOCATIONS. RAINFALL MAY ALSO PUSH SOME RIVERS TO BANKFULL OR MINOR FLOOD LATER IN THE WEEK. FOR THE FIRST FEW HOURS AFTER FRONTAL PASSAGE...TEMPERATURES WILL PLUMMET AT A RATE OF 6 TO 9 DEGREES PER HOUR. EXPECT TEMPERATURES TO APPROACH FREEZING FROM SOUTHEAST WEST VIRGINIA THROUGH THE NORTH CAROLINA MOUNTAINS BY EARLY EVENING...ALLOWING RAIN SHOWERS TO CHANGE OVER TO SNOW. WHILE WARM GROUND TEMPERATURES WILL CAUSE SNOW TO MELT ON CONTACT ACROSS MANY AREAS...MAY SEE UP TO A HALF INCH OF SNOW ACCUMULATE ALONG OUR MORE PROMINENT WEST FACING SLOPES BEFORE SNOW SHOWERS END OFF SHORTLY AFTER MIDNIGHT WEDNESDAY. NEXT WE GET TO DEAL WITH SUB FREEZING TEMPERATURES AREAWIDE BY SUNRISE WEDNESDAY. EXPECT OVERNIGHT LOWS TO RANGE FROM THE MID 20S ACROSS SOUTHEAST WEST VIRGINIA TO THE LOW 30S ACROSS THE SOUTHSIDE. PRECAUTIONS SHOULD BE TAKEN TO PROTECT ANY PLANTS THAT MAY BE KILLED BY FREEZING TEMPERATURES. HIGH PRESSURE WILL PASS FROM THE GREAT LAKES TO NEW ENGLAND ON WEDNESDAY...AND WILL BUILD SOUTHWARD ALONG THE EASTERN FACE OF THE APPALACHIANS. THE NORTHEASTERLY WIND FLOW AROUND THE HIGH WILL KEEP COOL CONDITIONS IN PLACE HEADING INTO THE SECOND HALF OF THE WORKWEEK...WITH FREEZING TEMPERATURES LIKELY AGAIN WEDNESDAY NIGHT. A GRADUAL WARM UP WILL TAKE PLACE THURSDAY AS WINDS ALOFT BEGIN TO SHIFT SOUTHWESTERLY AGAIN. && .LONG TERM /FRIDAY THROUGH SUNDAY/... AS OF 200 PM EDT SATURDAY... EXPECT HIGH PRESSURE TO REMAIN IN CONTROL OF THE WEATHER PATTERN FOR FRIDAY. A COLD FRONT WILL APPROACH FROM THE WEST FRIDAY NIGHT INTO SATURDAY. GENERALLY FOLLOWED WPCGUIDE FOR POPS. STILL LOOKS LIKE THE BEST CHANCE FOR WIDESPREAD RAIN WILL OCCUR ON FRIDAY NIGHT INTO SATURDAY. LEANED TOWARDS THE ECENS MEAN WITH HANDLING THE SOUTHERN STREAM SYSTEM AND ITS MOISTURE. TEMPERATURES MODERATE TOWARD NEXT WEEKEND CLOSER TO NORMAL. && .AVIATION /12Z MONDAY THROUGH FRIDAY/... AS OF 130 AM EDT MONDAY... MVFR CEILINGS HAD FILLED IN OVER THE SOUTHERN APPALACHIANS THIS MORNING. EXPECTING KDAN AND KROA TO GO IN AND OUT OF MVFR CLOUDS THROUGH 15Z/11AM. MODELS BRING THE SHORT WAVE OVER THE TENNESSEE VALLEY ACROSS THE REGION MAINLY BETWEEN 15Z/11AM AND 21Z/5PM. WITH ALL THE CLOUD COVER DURING THE DAY...THERE WILL BE ONLY A LIMITED THREAT OF ANY THUNDER. MODERATE CONFIDENCE THAT VISIBILITIES WILL REMAIN VFR AND NOT LOWER AS THESE SHOWERS MOVE THROUGH. THE STRONG COLD FRONT WILL ARRIVE IN THE MOUNTAINS AFTER 05Z/1AM TUESDAY. THIS RAIN WILL RESULT IN WIDESPREAD IFR TO MVFR CEILINGS AND VISIBILITIES. THE RAIN MAY BE HEAVY AT TIMES. LOOKS WET THRU TUESDAY NIGHT. STRONG GUSTY NW WINDS ARE LIKELY BEHIND THE FRONT TUESDAY AFTERNOON AND NIGHT. DRIER AIR WORKS IN BEHIND THE SYSTEM FOR WEDNESDAY ALTHOUGH RESIDUAL MOISTURE AND COLD AIR ALOFT MAY ACT TO KEEP MVFR CIGS OVER THE MOUNTAINS ON TUESDAY NIGHT. VFR THEN EXPECTED THURSDAY WITH HIGH PRESSURE RIDGING IN FROM OFF NEW ENGLAND BETWEEN THE EXITING FRONT OFFSHORE AND THE NEXT COLD FRONT TO THE NW. NEXT COLD FRONT APPROACHES FROM THE WEST FRIDAY BUT APPEARS SLOW ENOUGH TO MAINTAIN VFR DURING THE DAY FOR NOW. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...AMS NEAR TERM...AMS SHORT TERM...NF LONG TERM...KK AVIATION...AMS/JH
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
455 AM EDT MON APR 14 2014 .SYNOPSIS... LOW PRESSURE WAS OVER ILLINOIS WITH A COLD FRONT TRAILING FROM THE LOW INTO TEXAS. THIS FRONT WILL MOVE EAST TODAY AND TONIGHT AND WILL CROSS THE MID ATLANTIC REGION ON TUESDAY. BEHIND THE FRONT HIGH PRESSURE WILL BUILD IN FOR WEDNESDAY THROUGH FRIDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 415 AM EDT MONDAY... WATER VAPOR LOOP SHOWED A WELL DEFINED SHORT WAVE CROSSING THROUGH THE TENNESSE VALLEY. THICK CLOUD COVER WAS ALREADY SPREADING INTO THE COUNTY WARNING AREA FROM THE WEST. SHORT RANGE MODELS INCLUDING THE LATEST RUC/WRF AND HRRR BRING THE PRECIPITATION ASSOCIATED WITH THIS WAVE INTO THE WESTERN COUNTY WARNING AREA BETWEEN 15Z/11AM AND 18Z/2PM. WITH ALL THE CLOUD COVER DO NOT EXPECT MUCH INSTABILITY. BUFKIT OFF THE NAM AND GFS SHOWED LOW CAPE VALUES TODAY. HELD PROBABILITY OF THUNDER TO SLIGHT CHANCE. DO EXPECT ISOLATED TO SCATTERED SHOWERS AHEAD OF THE TENNESSEE VALLEY SHORT WAVE...WITH THE BETTER AREAL COVERAGE IN THE MOUNTAINS THROUGH NOON. HIGH TODAY WILL STILL BE ABOVE NORMAL BUT ONLY A SMALL RISE FROM THE CURRENT MILD TEMPERATURES. MUCH BETTER SYNOPTIC SCALE LIFT AFTER 00Z/8PM THIS EVENING. AS THE COLD FRONT APPROACHES LATE TONIGHT...SURFACE AND LOW LEVEL WINDS BACK...ADDING THE SOUTHEAST UPSLOPE COMPONENT TO THE STRONG FORCING. LARGEST PRECIPITATION AMOUNTS WILL BE AFTER MIDNIGHT. FRONT DOES NOT REACH THE FAR WESTERN PART OF THE FORECAST AREA BEFORE 12Z/8AM. STAYED CLOSER TO THE WARMER GUIDANCE FOR OVERNIGHT LOWS. THE LOW LEVEL JET INCREASES OVERNIGHT. HIGHER ELEVATIONS MAY HAVE GUSTS OF 25 TO 30 MPH. && .SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/... AS OF 400 AM EDT MONDAY... A STRONG COLD FRONT WILL MAKE ITS WAY ACROSS THE FORECAST AREA BEGINNING TUESDAY MORNING...AND THEREFORE WILL HAVE SEVERAL THINGS TO KEEP AN EYE. MODELS CONTINUE TO INDICATE A SOUTHWESTERLY 55KT LOW LEVEL JET DEVELOPING AHEAD OF THE FRONT. INSTABILITY AHEAD OF THE FRONT WILL BE MARGINAL...RESULTING IN MAINLY HEAVY SHOWER ACTIVITY WITH ONLY ISOLATED THUNDER AS THE FRONT PASSES. HOWEVER...WITH THE JET BLOWING JUST OFF THE SURFACE OVER THE MOUNTAINS...WOULD NOT BE SURPRISED TO SEE SOME OF THE MORE INTENSE SHOWER ACTIVITY DRAW THE STRONGER WINDS DOWN TO THE GROUND LEVEL. HIGH PRESSURE WILL BUILD IN QUICKLY AFTER THE COLD FRONT PASSES... RESULTING IN A ROUGHLY 10MB PRESSURE GRADIENT ACROSS THE FORECAST AREA FROM MID AFTERNOON THROUGH ALMOST MIDNIGHT. EXPECT STRONG NORTHWEST WINDS WITH 40 TO 50 MPH GUSTS ACROSS THE MOUNTAINS...WITH THE STRONGEST GUSTS FOUND ALONG THE BLUE RIDGE PARKWAY SOUTH OF ROANOKE. THESE GUSTS...WHEN COMBINED WITH PROLONGED RAINFALL...WILL LIKELY BE ENOUGH TO BRING DOWN A FEW TREES...AND RESULT IN LOCALIZED POWER OUTAGES. RAINFALL WILL BE WIDESPREAD AND HEAVY AT TIMES...WITH A STORM TOTAL AMOUNT OF OVER AN INCH FOR THE ENTIRE FORECAST AREA...WITH AROUND 2 INCHES EXPECTED ALONG THE BLUE RIDGE. MAY SEE LOCALIZED MINOR FLOODING ISSUES DEVELOP WHERE BANDS OF HEAVY RAIN PASS REPEATEDLY OVER THE SAME LOCATIONS. RAINFALL MAY ALSO PUSH SOME RIVERS TO BANKFULL OR MINOR FLOOD LATER IN THE WEEK. FOR THE FIRST FEW HOURS AFTER FRONTAL PASSAGE...TEMPERATURES WILL PLUMMET AT A RATE OF 6 TO 9 DEGREES PER HOUR. EXPECT TEMPERATURES TO APPROACH FREEZING FROM SOUTHEAST WEST VIRGINIA THROUGH THE NORTH CAROLINA MOUNTAINS BY EARLY EVENING...ALLOWING RAIN SHOWERS TO CHANGE OVER TO SNOW. WHILE WARM GROUND TEMPERATURES WILL CAUSE SNOW TO MELT ON CONTACT ACROSS MANY AREAS...MAY SEE UP TO A HALF INCH OF SNOW ACCUMULATE ALONG OUR MORE PROMINENT WEST FACING SLOPES BEFORE SNOW SHOWERS END OFF SHORTLY AFTER MIDNIGHT WEDNESDAY. NEXT WE GET TO DEAL WITH SUB FREEZING TEMPERATURES AREAWIDE BY SUNRISE WEDNESDAY. EXPECT OVERNIGHT LOWS TO RANGE FROM THE MID 20S ACROSS SOUTHEAST WEST VIRGINIA TO THE LOW 30S ACROSS THE SOUTHSIDE. PRECAUTIONS SHOULD BE TAKEN TO PROTECT ANY PLANTS THAT MAY BE KILLED BY FREEZING TEMPERATURES. HIGH PRESSURE WILL PASS FROM THE GREAT LAKES TO NEW ENGLAND ON WEDNESDAY...AND WILL BUILD SOUTHWARD ALONG THE EASTERN FACE OF THE APPALACHIANS. THE NORTHEASTERLY WIND FLOW AROUND THE HIGH WILL KEEP COOL CONDITIONS IN PLACE HEADING INTO THE SECOND HALF OF THE WORKWEEK...WITH FREEZING TEMPERATURES LIKELY AGAIN WEDNESDAY NIGHT. A GRADUAL WARM UP WILL TAKE PLACE THURSDAY AS WINDS ALOFT BEGIN TO SHIFT SOUTHWESTERLY AGAIN. && .LONG TERM /FRIDAY THROUGH SUNDAY/... AS OF 200 PM EDT SATURDAY... EXPECT HIGH PRESSURE TO REMAIN IN CONTROL OF THE WEATHER PATTERN FOR FRIDAY. A COLD FRONT WILL APPROACH FROM THE WEST FRIDAY NIGHT INTO SATURDAY. GENERALLY FOLLOWED WPCGUIDE FOR POPS. STILL LOOKS LIKE THE BEST CHANCE FOR WIDESPREAD RAIN WILL OCCUR ON FRIDAY NIGHT INTO SATURDAY. LEANED TOWARDS THE ECENS MEAN WITH HANDLING THE SOUTHERN STREAM SYSTEM AND ITS MOISTURE. TEMPERATURES MODERATE TOWARD NEXT WEEKEND CLOSER TO NORMAL. && .AVIATION /08Z MONDAY THROUGH FRIDAY/... AS OF 130 AM EDT MONDAY... CEILINGS WILL GRADUALLY LOWER THIS MORNING. MVFR CLOUDS WILL FORM ALONG THE BLUE RIDGE AND IN THE FOOTHILLS BEFORE 12Z. THERE IS A LOW POSSIBILITY THAT CEILINGS WILL EVEN DROP TO IFR AT KBCB BEFORE 12Z. MODELS BRING THE SHORT WAVE ENTERING THE TENNESSEE VALLEY ACROSS THE REGION MAINLY BETWEEN 15Z/11AM AND 21Z/5PM. WITH ALL THE CLOUD COVER DURING THE DAY...THERE WILL BE ONLY A LIMITED THREAT OF ANY THUNDER. MODERATE CONFIDENCE THAT VISIBILITIES WILL REMAIN VFR AND NOT LOWER AS THE SHOWERS MOVE THROUGH. THE STRONG COLD FRONT WILL ARRIVE IN THE MOUNTAINS BY 12Z/8AM TUESDAY. WILL HOLD OFF ADDING ANOTHER PERIOD OF RAINFALL IN UNTIL AFTER THE END OF THE 06Z TAFS. LOOKS WET TUESDAY THRU TUESDAY NIGHT. STRONG GUSTY NW WINDS ARE LIKELY BEHIND THE FRONT TUESDAY AFTERNOON AND NIGHT. DRIER AIR WORKS IN BEHIND THE SYSTEM FOR WEDNESDAY ALTHOUGH RESIDUAL MOISTURE AND COLD AIR ALOFT MAY ACT TO KEEP MVFR CIGS OVER THE MOUNTAINS ON TUESDAY NIGHT. VFR THEN EXPECTED THURSDAY WITH HIGH PRESSURE RIDGING IN FROM OFF NEW ENGLAND BETWEEN THE EXITING FRONT OFFSHORE AND THE NEXT COLD FRONT TO THE NW. NEXT COLD FRONT APPROACHES FROM THE WEST FRIDAY BUT APPEARS SLOW ENOUGH TO MAINTAIN VFR DURING THE DAY FOR NOW. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...AMS NEAR TERM...AMS SHORT TERM...NF LONG TERM...KK AVIATION...AMS/JH
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1220 PM CDT MON APR 14 2014 .SHORT TERM...(TODAY THROUGH WEDNESDAY) ISSUED AT 345 AM CDT MON APR 14 2014 MAIN FORECAST CONCERN IS WITH THE PRECIPITATION CHANCES TODAY AND THEN TUESDAY NIGHT INTO WEDNESDAY. SURFACE ANALYSIS SHOWS AN AREA OF LOW PRESSURE OVER NORTHERN ILLINOIS. LOCAL AND REGIONAL RADARS SHOWING THE DEFORMATION BAND OF PRECIPITATION ON THE NORTHWEST SIDE OF THE LOW EXTENDS FROM SOUTHERN IOWA ACROSS THE AREA INTO EASTERN LAKE SUPERIOR. COLDER AIR HAS FILTERED IN AND CHANGED MOST OF THE PRECIPITATION OVER TO SOME LIGHT SNOW. THE PRECIPITATION IS MOVING TO THE NORTHEAST AND THE 14.05Z HRRR SEEMS TO HAVE A GOOD HANDLE ON THE CURRENT SITUATION. IT INDICATES THAT BY 12Z THE BACK EDGE OF THE PRECIPITATION COMING OUT OF SOUTHERN IOWA WILL HAVE SHIFTED INTO SOUTHERN WISCONSIN WITH THE WESTERN EDGE INTO THE WESTERN AND CENTRAL PARTS OF WISCONSIN. WILL ADJUST THE MORNING SNOW CHANCES BASED ON RADAR TRENDS...BUT EXPECT THAT THE MAJORITY OF THE ACTIVITY SHOULD BE EAST OF THE FORECAST AREA BY 12Z AND THEN WHAT IT IS LEFT WILL QUICKLY DISSIPATE BY THE MID MORNING HOURS. HIGH PRESSURE WILL THEN BUILD IN OVER THE UPPER MIDWEST AND LINGER INTO TUESDAY BEFORE DEPARTING TO THE NORTHEAST. THE HIGH WILL HELP TO KEEP TEMPERATURES BELOW NORMAL WITH HIGHS TODAY ONLY IN THE 30S FOR THE ENTIRE AREA AND THEN IN THE 30S AND 40S FOR TUESDAY. THE NEXT CHANCE FOR SOME PRECIPITATION WILL START TO COME IN TUESDAY NIGHT AND CONTINUE INTO WEDNESDAY. THIS WILL BE IN RESPONSE TO A SHORT WAVE TROUGH THAT WILL CROSS THE NORTHERN ROCKIES TUESDAY NIGHT AND MOVE OUT OVER THE UPPER MIDWEST WEDNESDAY. THE BEST PV ADVECTION IN THE 500-300 MB LAYER IS EXPECTED TO REMAIN NORTHWEST OF THE AREA THROUGH WEDNESDAY...BUT THE WAVE SHOULD STILL BE ABLE TO PRODUCE AT LEAST SOME WEAK PV ADVECTION OVER THE NORTHWEST SECTIONS OF THE FORECAST AREA. LOW PRESSURE AT THE SURFACE IS EXPECTED TO MOVE EAST ACROSS SOUTH DAKOTA DURING THE DAY WEDNESDAY WITH A WARM FRONT EXTENDING EAST INTO WISCONSIN. WEAK FRONTOGENESIS IN THE 1000-700 MB LAYER IS EXPECTED TO DEVELOP ALONG AND NORTH OF THE WARM FRONT ACROSS MINNESOTA AND WISCONSIN. THE WARM AIR ADVECTION AHEAD OF THE SHORT WAVE TROUGH AND SURFACE LOW IS EXPECTED TO PRODUCE 5 TO 8 UBAR/S OF UP GLIDE ON THE 290K ISENTROPIC SURFACE. WITH THE FORCING FROM THE SHORT WAVE TROUGH AND THE LOW LEVEL FRONTOGENESIS AND ISENTROPIC UP GLIDE...EXPECT TO SEE PRECIPITATION BEGIN TO DEVELOP ALONG AND NORTH OF THE WARM FRONT LATE TUESDAY NIGHT AND CONTINUE INTO WEDNESDAY. WILL START OUT WITH SOME SMALL CHANCES ALONG AND NORTH OF INTERSTATE 94 LATE TUESDAY NIGHT AND THEN SPREAD THE CHANCES SOUTH TO ABOUT THE IOWA/MINNESOTA BORDER WEDNESDAY WHILE INCREASING TO 50 PERCENT ACROSS THE FAR NORTH. BUFKIT SOUNDINGS INDICATE THAT ICE WILL BE PRESENT IN THE CLOUDS AND THERE SHOULD NOT BE A WARM LAYER TO DEAL WITH...SO THE PRECIPITATION TYPE SHOULD BE CONTROLLED BY THE BOUNDARY LAYER TEMPERATURES. WILL START WITH ALL SNOW TUESDAY NIGHT GOING TO RAIN WEDNESDAY AS READINGS WARM INTO THE 40S AND 50S. .LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY) ISSUED AT 345 AM CDT MON APR 14 2014 SLOW AND COMPLICATED UPPER AIR PATTERN WILL KEEP THE PRECIPITATION CHANCES IN THE FORECAST THROUGH THE WEEKEND. ONCE THE FIRST SHORT WAVE TROUGH MOVES PAST THE REGION WEDNESDAY NIGHT...ALL THE MODELS SHOW A CUT OFF LOW FORMING OVER SOUTHERN SASKATCHEWAN FROM A STRONG NORTHERN STREAM SHORT WAVE TROUGH COMING DOWN FROM THE NORTHERN CANADA. THIS IS EXPECTED TO KEEP THE MEAN LONG WAVE TROUGH ALONG AND EAST OF THE ROCKIES WITH SEVERAL SHORT WAVE TROUGHS COMING THROUGH THIS LONG WAVE TROUGH. THE CLOSED LOW SHOULD THEN OPEN UP AND START TO MOVE EAST WITH THE LONG WAVE TROUGH PASSING OVER FOR THE WEEKEND. WITHIN THIS EXTENDED PERIOD OF PRECIPITATION CHANCES...THE BEST CHANCES LOOK TO OCCUR THURSDAY NIGHT INTO FRIDAY WHEN A STRONG SHORT WAVE TROUGH IS SHOWN BY THE MODELS TO MOVE ACROSS THE REGION. TEMPERATURES STILL LOOK TO BE COOL ENOUGH FOR SNOW OR A RAIN/SNOW MIX AT NIGHT GOING TO RAIN DURING THE DAY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1220 PM CDT MON APR 14 2014 LOWER CLOUDS FLIRTING WITH THE MVFR/VFR THRESH-HOLD HAVE BEEN SLOWLY CLEARING THE TAF SITES THRU THE MORNING. ONCE THESE ARE SOUTHEAST OF THE TAF SITES BY 19-20Z...GOOD VFR CONDITIONS EXPECTED THRU TONIGHT/ TUE MORNING AS COLD/DRY CANADIAN HIGH PRESSURE DRIFTS EAST ACROSS THE UPPER MIDWEST. THE BRISK NORTH TO NORTHWEST WINDS WILL PERSIST THRU MID AFTERNOON...THEN DIMINISH RATHER QUICKLY BY OR AFTER 23Z AS THE SFC RIDGE AXIS APPROACHES/MOVES ACROSS THE AREA AND THE MIXED DEPTH DECREASES AROUND SUNSET. && .HYDROLOGY... ISSUED AT 345 AM CDT MON APR 14 2014 PARTS OF SOUTHWEST WISCONSIN RECEIVED BETWEEN 2 AND 4 INCHES OF RAIN OVER THE WEEKEND. THIS HAS RESULTED IN SATURATED SOILS AND RUNOFF INTO AREAS STREAMS. THIS HAS RESULTED IN MAINLY IN BANK RISES BUT THE LATEST FORECASTS INDICATE SOME MINOR FLOODING IS POSSIBLE ALONG THE KICKAPOO IN THE VICINITY OF READSTOWN. SOME FLOODING LATER THIS WEEK IS POSSIBLE ALONG THE MISSISSIPPI RIVER AS RUNOFF FROM THE SNOWMELT UPSTREAM AND THE RECENT RAINS MOVES DOWNSTREAM. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...04 LONG TERM...04 AVIATION...DAS HYDROLOGY...04
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
644 AM CDT MON APR 14 2014 .SHORT TERM...(TODAY THROUGH WEDNESDAY) ISSUED AT 345 AM CDT MON APR 14 2014 MAIN FORECAST CONCERN IS WITH THE PRECIPITATION CHANCES TODAY AND THEN TUESDAY NIGHT INTO WEDNESDAY. SURFACE ANALYSIS SHOWS AN AREA OF LOW PRESSURE OVER NORTHERN ILLINOIS. LOCAL AND REGIONAL RADARS SHOWING THE DEFORMATION BAND OF PRECIPITATION ON THE NORTHWEST SIDE OF THE LOW EXTENDS FROM SOUTHERN IOWA ACROSS THE AREA INTO EASTERN LAKE SUPERIOR. COLDER AIR HAS FILTERED IN AND CHANGED MOST OF THE PRECIPITATION OVER TO SOME LIGHT SNOW. THE PRECIPITATION IS MOVING TO THE NORTHEAST AND THE 14.05Z HRRR SEEMS TO HAVE A GOOD HANDLE ON THE CURRENT SITUATION. IT INDICATES THAT BY 12Z THE BACK EDGE OF THE PRECIPITATION COMING OUT OF SOUTHERN IOWA WILL HAVE SHIFTED INTO SOUTHERN WISCONSIN WITH THE WESTERN EDGE INTO THE WESTERN AND CENTRAL PARTS OF WISCONSIN. WILL ADJUST THE MORNING SNOW CHANCES BASED ON RADAR TRENDS...BUT EXPECT THAT THE MAJORITY OF THE ACTIVITY SHOULD BE EAST OF THE FORECAST AREA BY 12Z AND THEN WHAT IT IS LEFT WILL QUICKLY DISSIPATE BY THE MID MORNING HOURS. HIGH PRESSURE WILL THEN BUILD IN OVER THE UPPER MIDWEST AND LINGER INTO TUESDAY BEFORE DEPARTING TO THE NORTHEAST. THE HIGH WILL HELP TO KEEP TEMPERATURES BELOW NORMAL WITH HIGHS TODAY ONLY IN THE 30S FOR THE ENTIRE AREA AND THEN IN THE 30S AND 40S FOR TUESDAY. THE NEXT CHANCE FOR SOME PRECIPITATION WILL START TO COME IN TUESDAY NIGHT AND CONTINUE INTO WEDNESDAY. THIS WILL BE IN RESPONSE TO A SHORT WAVE TROUGH THAT WILL CROSS THE NORTHERN ROCKIES TUESDAY NIGHT AND MOVE OUT OVER THE UPPER MIDWEST WEDNESDAY. THE BEST PV ADVECTION IN THE 500-300 MB LAYER IS EXPECTED TO REMAIN NORTHWEST OF THE AREA THROUGH WEDNESDAY...BUT THE WAVE SHOULD STILL BE ABLE TO PRODUCE AT LEAST SOME WEAK PV ADVECTION OVER THE NORTHWEST SECTIONS OF THE FORECAST AREA. LOW PRESSURE AT THE SURFACE IS EXPECTED TO MOVE EAST ACROSS SOUTH DAKOTA DURING THE DAY WEDNESDAY WITH A WARM FRONT EXTENDING EAST INTO WISCONSIN. WEAK FRONTOGENESIS IN THE 1000-700 MB LAYER IS EXPECTED TO DEVELOP ALONG AND NORTH OF THE WARM FRONT ACROSS MINNESOTA AND WISCONSIN. THE WARM AIR ADVECTION AHEAD OF THE SHORT WAVE TROUGH AND SURFACE LOW IS EXPECTED TO PRODUCE 5 TO 8 UBAR/S OF UP GLIDE ON THE 290K ISENTROPIC SURFACE. WITH THE FORCING FROM THE SHORT WAVE TROUGH AND THE LOW LEVEL FRONTOGENESIS AND ISENTROPIC UP GLIDE...EXPECT TO SEE PRECIPITATION BEGIN TO DEVELOP ALONG AND NORTH OF THE WARM FRONT LATE TUESDAY NIGHT AND CONTINUE INTO WEDNESDAY. WILL START OUT WITH SOME SMALL CHANCES ALONG AND NORTH OF INTERSTATE 94 LATE TUESDAY NIGHT AND THEN SPREAD THE CHANCES SOUTH TO ABOUT THE IOWA/MINNESOTA BORDER WEDNESDAY WHILE INCREASING TO 50 PERCENT ACROSS THE FAR NORTH. BUFKIT SOUNDINGS INDICATE THAT ICE WILL BE PRESENT IN THE CLOUDS AND THERE SHOULD NOT BE A WARM LAYER TO DEAL WITH...SO THE PRECIPITATION TYPE SHOULD BE CONTROLLED BY THE BOUNDARY LAYER TEMPERATURES. WILL START WITH ALL SNOW TUESDAY NIGHT GOING TO RAIN WEDNESDAY AS READINGS WARM INTO THE 40S AND 50S. .LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY) ISSUED AT 345 AM CDT MON APR 14 2014 SLOW AND COMPLICATED UPPER AIR PATTERN WILL KEEP THE PRECIPITATION CHANCES IN THE FORECAST THROUGH THE WEEKEND. ONCE THE FIRST SHORT WAVE TROUGH MOVES PAST THE REGION WEDNESDAY NIGHT...ALL THE MODELS SHOW A CUT OFF LOW FORMING OVER SOUTHERN SASKATCHEWAN FROM A STRONG NORTHERN STREAM SHORT WAVE TROUGH COMING DOWN FROM THE NORTHERN CANADA. THIS IS EXPECTED TO KEEP THE MEAN LONG WAVE TROUGH ALONG AND EAST OF THE ROCKIES WITH SEVERAL SHORT WAVE TROUGHS COMING THROUGH THIS LONG WAVE TROUGH. THE CLOSED LOW SHOULD THEN OPEN UP AND START TO MOVE EAST WITH THE LONG WAVE TROUGH PASSING OVER FOR THE WEEKEND. WITHIN THIS EXTENDED PERIOD OF PRECIPITATION CHANCES...THE BEST CHANCES LOOK TO OCCUR THURSDAY NIGHT INTO FRIDAY WHEN A STRONG SHORT WAVE TROUGH IS SHOWN BY THE MODELS TO MOVE ACROSS THE REGION. TEMPERATURES STILL LOOK TO BE COOL ENOUGH FOR SNOW OR A RAIN/SNOW MIX AT NIGHT GOING TO RAIN DURING THE DAY. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 644 AM CDT MON APR 14 2014 NOW THAT THE SNOW HAS EXITED EAST OF THE AREA...MAIN CONCERN TURNS TO WINDS AND CLOUD COVER. LOOKING FOR MVFR CLOUDS TO SCATTER KRST BY 13Z AND KLSE BY 15Z...LEAVING A VFR CIG OF MID- CLOUD/ALTOCUMULUS. STEEPENING LAPSE RATES THIS AFTERNOON EXPECTED TO PRODUCE CUMULUS WITH VFR BASES IN THE 4-5KFT RANGE. LOOK FOR THIS TO SCATTER OUT AFTER SUNSET WITH LOSS OF SURFACE HEATING. OTHERWISE...A TIGHT PRESSURE GRADIENT WILL EXIST ACROSS THE AREA TODAY BETWEEN LOW PRESSURE OVER THE GREAT LAKES AND HIGH PRESSURE BUILDING IN FROM THE NORTHERN PLAINS. AS A RESULT...PLAN ON NORTH/NORTHWEST WINDS IN THE 15-25KT RANGE SUSTAINED WITH GUSTS AROUND 30KT. THIS WINDS WILL SUBSIDE RAPIDLY THIS EVENING AFTER SUNSET WITH LOSS OF DEEPER MIXING AND AS HIGH PRESSURE BUILDING OVERHEAD. && .HYDROLOGY... ISSUED AT 345 AM CDT MON APR 14 2014 PARTS OF SOUTHWEST WISCONSIN RECEIVED BETWEEN 2 AND 4 INCHES OF RAIN OVER THE WEEKEND. THIS HAS RESULTED IN SATURATED SOILS AND RUNOFF INTO AREAS STREAMS. THIS HAS RESULTED IN MAINLY IN BANK RISES BUT THE LATEST FORECASTS INDICATE SOME MINOR FLOODING IS POSSIBLE ALONG THE KICKAPOO IN THE VICINITY OF READSTOWN. SOME FLOODING LATER THIS WEEK IS POSSIBLE ALONG THE MISSISSIPPI RIVER AS RUNOFF FROM THE SNOWMELT UPSTREAM AND THE RECENT RAINS MOVES DOWNSTREAM. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...04 LONG TERM...04 AVIATION...DAS HYDROLOGY...04
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
345 AM CDT MON APR 14 2014 .SHORT TERM...(TODAY THROUGH WEDNESDAY) ISSUED AT 345 AM CDT MON APR 14 2014 MAIN FORECAST CONCERN IS WITH THE PRECIPITATION CHANCES TODAY AND THEN TUESDAY NIGHT INTO WEDNESDAY. SURFACE ANALYSIS SHOWS AN AREA OF LOW PRESSURE OVER NORTHERN ILLINOIS. LOCAL AND REGIONAL RADARS SHOWING THE DEFORMATION BAND OF PRECIPITATION ON THE NORTHWEST SIDE OF THE LOW EXTENDS FROM SOUTHERN IOWA ACROSS THE AREA INTO EASTERN LAKE SUPERIOR. COLDER AIR HAS FILTERED IN AND CHANGED MOST OF THE PRECIPITATION OVER TO SOME LIGHT SNOW. THE PRECIPITATION IS MOVING TO THE NORTHEAST AND THE 14.05Z HRRR SEEMS TO HAVE A GOOD HANDLE ON THE CURRENT SITUATION. IT INDICATES THAT BY 12Z THE BACK EDGE OF THE PRECIPITATION COMING OUT OF SOUTHERN IOWA WILL HAVE SHIFTED INTO SOUTHERN WISCONSIN WITH THE WESTERN EDGE INTO THE WESTERN AND CENTRAL PARTS OF WISCONSIN. WILL ADJUST THE MORNING SNOW CHANCES BASED ON RADAR TRENDS...BUT EXPECT THAT THE MAJORITY OF THE ACTIVITY SHOULD BE EAST OF THE FORECAST AREA BY 12Z AND THEN WHAT IT IS LEFT WILL QUICKLY DISSIPATE BY THE MID MORNING HOURS. HIGH PRESSURE WILL THEN BUILD IN OVER THE UPPER MIDWEST AND LINGER INTO TUESDAY BEFORE DEPARTING TO THE NORTHEAST. THE HIGH WILL HELP TO KEEP TEMPERATURES BELOW NORMAL WITH HIGHS TODAY ONLY IN THE 30S FOR THE ENTIRE AREA AND THEN IN THE 30S AND 40S FOR TUESDAY. THE NEXT CHANCE FOR SOME PRECIPITATION WILL START TO COME IN TUESDAY NIGHT AND CONTINUE INTO WEDNESDAY. THIS WILL BE IN RESPONSE TO A SHORT WAVE TROUGH THAT WILL CROSS THE NORTHERN ROCKIES TUESDAY NIGHT AND MOVE OUT OVER THE UPPER MIDWEST WEDNESDAY. THE BEST PV ADVECTION IN THE 500-300 MB LAYER IS EXPECTED TO REMAIN NORTHWEST OF THE AREA THROUGH WEDNESDAY...BUT THE WAVE SHOULD STILL BE ABLE TO PRODUCE AT LEAST SOME WEAK PV ADVECTION OVER THE NORTHWEST SECTIONS OF THE FORECAST AREA. LOW PRESSURE AT THE SURFACE IS EXPECTED TO MOVE EAST ACROSS SOUTH DAKOTA DURING THE DAY WEDNESDAY WITH A WARM FRONT EXTENDING EAST INTO WISCONSIN. WEAK FRONTOGENESIS IN THE 1000-700 MB LAYER IS EXPECTED TO DEVELOP ALONG AND NORTH OF THE WARM FRONT ACROSS MINNESOTA AND WISCONSIN. THE WARM AIR ADVECTION AHEAD OF THE SHORT WAVE TROUGH AND SURFACE LOW IS EXPECTED TO PRODUCE 5 TO 8 UBAR/S OF UP GLIDE ON THE 290K ISENTROPIC SURFACE. WITH THE FORCING FROM THE SHORT WAVE TROUGH AND THE LOW LEVEL FRONTOGENESIS AND ISENTROPIC UP GLIDE...EXPECT TO SEE PRECIPITATION BEGIN TO DEVELOP ALONG AND NORTH OF THE WARM FRONT LATE TUESDAY NIGHT AND CONTINUE INTO WEDNESDAY. WILL START OUT WITH SOME SMALL CHANCES ALONG AND NORTH OF INTERSTATE 94 LATE TUESDAY NIGHT AND THEN SPREAD THE CHANCES SOUTH TO ABOUT THE IOWA/MINNESOTA BORDER WEDNESDAY WHILE INCREASING TO 50 PERCENT ACROSS THE FAR NORTH. BUFKIT SOUNDINGS INDICATE THAT ICE WILL BE PRESENT IN THE CLOUDS AND THERE SHOULD NOT BE A WARM LAYER TO DEAL WITH...SO THE PRECIPITATION TYPE SHOULD BE CONTROLLED BY THE BOUNDARY LAYER TEMPERATURES. WILL START WITH ALL SNOW TUESDAY NIGHT GOING TO RAIN WEDNESDAY AS READINGS WARM INTO THE 40S AND 50S. .LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY) ISSUED AT 345 AM CDT MON APR 14 2014 SLOW AND COMPLICATED UPPER AIR PATTERN WILL KEEP THE PRECIPITATION CHANCES IN THE FORECAST THROUGH THE WEEKEND. ONCE THE FIRST SHORT WAVE TROUGH MOVES PAST THE REGION WEDNESDAY NIGHT...ALL THE MODELS SHOW A CUT OFF LOW FORMING OVER SOUTHERN SASKATCHEWAN FROM A STRONG NORTHERN STREAM SHORT WAVE TROUGH COMING DOWN FROM THE NORTHERN CANADA. THIS IS EXPECTED TO KEEP THE MEAN LONG WAVE TROUGH ALONG AND EAST OF THE ROCKIES WITH SEVERAL SHORT WAVE TROUGHS COMING THROUGH THIS LONG WAVE TROUGH. THE CLOSED LOW SHOULD THEN OPEN UP AND START TO MOVE EAST WITH THE LONG WAVE TROUGH PASSING OVER FOR THE WEEKEND. WITHIN THIS EXTENDED PERIOD OF PRECIPITATION CHANCES...THE BEST CHANCES LOOK TO OCCUR THURSDAY NIGHT INTO FRIDAY WHEN A STRONG SHORT WAVE TROUGH IS SHOWN BY THE MODELS TO MOVE ACROSS THE REGION. TEMPERATURES STILL LOOK TO BE COOL ENOUGH FOR SNOW OR A RAIN/SNOW MIX AT NIGHT GOING TO RAIN DURING THE DAY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1140 PM CDT SUN APR 13 2014 AS SHORT WAVE CONTINUES TO PUSH EAST TONIGHT...PRECIPITATION HAS BEEN WAINING. COLUMN HAS BEEN COOLING AS WELL ALLOWING RAIN TO CHANGE OVER TO SNOW FROM WEST TO EAST. BUT OVERALL CONDITIONS HAVE BEEN IMPROVING WITH LESS LIFR AND MORE MVFR BEING OBSERVED AROUND THE AREA. OVER THE NEXT FEW HOURS...EXPECT RAIN AND SNOW TO END. BEFORE THEN COULD SEE A DEFORMATION ZONE DEVELOP AND BRING ONE MORE ROUND OF SNOW TO KRST BEFORE ENDING. MVFR CEILINGS EXPECTED TOWARDS DAYBREAK AND THEN AS SYSTEM EXITS...COULD SEE VFR FOR MUCH OF THE DAY. A BIT UNSURE ON WHAT CLOUDS WILL DO MONDAY AFTERNOON AS UPPER TROUGH SETTLES IN. COULD SEE SOME LOW CLOUD DEVELOPMENT GIVEN MID APRIL SUN BUT AM BANKING THAT MID LEVEL CLOUDS AROUND WILL BE ABOUT IT. STIFF NORTHWEST WINDS SHOULD ALSO SUBSIDE AS WEATHER SYSTEM EXITS BY MONDAY EVENING. && .HYDROLOGY... ISSUED AT 345 AM CDT MON APR 14 2014 PARTS OF SOUTHWEST WISCONSIN RECEIVED BETWEEN 2 AND 4 INCHES OF RAIN OVER THE WEEKEND. THIS HAS RESULTED IN SATURATED SOILS AND RUNOFF INTO AREAS STREAMS. THIS HAS RESULTED IN MAINLY IN BANK RISES BUT THE LATEST FORECASTS INDICATE SOME MINOR FLOODING IS POSSIBLE ALONG THE KICKAPOO IN THE VICINITY OF READSTOWN. SOME FLOODING LATER THIS WEEK IS POSSIBLE ALONG THE MISSISSIPPI RIVER AS RUNOFF FROM THE SNOWMELT UPSTREAM AND THE RECENT RAINS MOVES DOWNSTREAM. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...04 LONG TERM...04 AVIATION...SHEA HYDROLOGY...04
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1140 PM CDT SUN APR 13 2014 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 343 PM CDT SUN APR 13 2014 BUSY PERIOD TONIGHT INTO TOMORROW MORNING AS A LOW PRESSURE SYSTEM TRACKS THROUGH NORTHERN ILLINOIS. HEAVY RAIN...SNOW...AND STRONG WINDS ARE ALL CONCERNS TONIGHT INTO TOMORROW MORNING. CURRENTLY...THE LEAD MID LEVEL TROUGH IS PROPAGATING TO THE NORTH ACROSS THE MID-MISSISSIPPI RIVER VALLEY WITH SOME LOW LEVEL CONVERGENCE OCCURRING ALONG A SOUTHWEST TO NORTHEAST ORIENTED WARM FRONT THAT RUNS FROM SOUTHEAST IOWA THROUGH SOUTHERN WISCONSIN. MODERATE TO HEAVY RAIN HAS ALREADY MOVED INTO NORTHEAST IOWA AND SOUTHWEST WISCONSIN AND WILL CONTINUE TO TRACK TO THE NORTHEAST INTO THIS EVENING AS THE SURFACE LOW MOVES UP IN THE REGION. MOST OF THE 0-3KM MUCAPE THAT THE 13.19Z RAP SHOWS STAYS IN NORTHERN ILLINOIS AND DOES NOT REACH THE REGION. SO...THINKING THAT THERE SHOULD NOT BE MUCH LIGHTNING WITH THIS RAIN INTO THE EVENING HOURS. WITH 1 TO 2 INCHES OF RAIN STILL FORECAST FOR THE SAME AREAS THAT WERE HIT BY 1 TO 3 INCHES OF RAIN YESTERDAY...HAVE KEPT THE FLOOD WATCH GOING FOR NORTHEAST IOWA AND SOUTHWEST WISCONSIN. TO THE WEST SIDE OF THE SYSTEM WE GO WHERE THE CONCERN IS ON WHEN THE THERMAL PROFILE WILL COOL ENOUGH TO CHANGE THE PRECIPITATION OVER TO ALL SNOW ALONG WITH HOW WINDY IT WILL BE. IN REGARD TO THE SNOW...WITH LOW TO MID LEVEL COLD AIR ADVECTION KICKING IN THIS EVENING AS THE LOW DEEPENS...THE PRECIPITATION TYPE WILL BE DEPENDENT UPON WHAT THE SURFACE TEMPERATURES ARE. LOOKING OUT WEST RIGHT NOW...MOST OBSERVATIONS THAT ARE REPORTING SNOW ARE IN THE 30F TO 35F RANGE THOUGH SOME OF THESE TEMPERATURE DROPS APPEAR TO BE DUE TO EVAPORATIVE COOLING THANKS TO THE PRECIPITATION FALLING THROUGH THE COLUMN. BASED ON THE 13.19Z RAP & 13.12Z NAM/GFS SOUNDINGS...IT LOOKS LIKE THE CHANGE OVER SHOULD OCCUR TO ALL SNOW THIS EVENING BETWEEN 8-10PM IN NORTH CENTRAL IOWA AND SOUTHEAST MINNESOTA. THIS CHANGE OVER WILL THEN GRADUALLY PUSH EASTWARD INTO WESTERN WISCONSIN OVERNIGHT. SNOW TOTALS ARE PROBLEMATIC AS A RESULT SINCE A LOT HINGES ON HOW FAST THE CHANGE OVER OCCURS...IS THERE STRONG FORCING STILL THERE AS THE COLD AIR ARRIVES...AND ALSO IF THERE EVEN IS ICE THERE AS A LOT OF THE SOUNDINGS SHOW A DRY LAYER BETWEEN -8C TO -20C. MOST OF THE 13.12Z COBB DATA FROM THE NAM/GFS IS SHOWING ABOUT 1 TO 2 INCHES OCCURRING OVERNIGHT THOUGH A LOT OF THE SREF DATA IS MUCH HIGHER THAN THAT. GIVEN THE NUMBER OF NEGATIVES WORKING AGAINST THIS...TRENDED TOWARD THESE LOWER TOTALS WHICH STILL ARE A BIT HIGHER THAN WHAT PREVIOUSLY WAS BEING FORECAST BY GUIDANCE. THE MAIN SNOW SHOULD FALL BETWEEN 7PM-1AM IN NORTHEAST IOWA/SOUTHEAST MINNESOTA AND THEN BETWEEN 1AM-7AM IN WESTERN WISCONSIN/FAR NORTHEAST IOWA. WINDS WILL CONTINUALLY INCREASE THROUGH TONIGHT AS THE PRESSURE GRADIENT TIGHTENS UP WITH THE LOW. THE STRONGEST LOW LEVEL WINDS HAVE ALREADY DEVELOPED ACROSS WESTERN IOWA WHERE 30 TO 40KT WINDS ARE FAIRLY WIDESPREAD IN THE AREA WHERE SNOW IS FALLING. CONCERNED THAT THESE CONDITIONS WILL TRANSLATE EASTWARD INTO NORTHEAST IOWA AND SOUTHEAST MINNESOTA THIS EVENING. THE STRONGEST WINDS LOOK LIKE THEY WILL MAINLY BE IN NORTHEAST IOWA WITH BUFKIT SOUNDINGS SHOWING SOME 35 TO 40KT WINDS MIXING DOWN AS THE SNOW IS COMING DOWN. DISCUSSED THE IDEA OF DOING A WINTER WEATHER OR WIND ADVISORY WITH MPX/DMX...BUT DECIDED THAT THE WIND GUSTS MAY NOT HIT ADVISORY CRITERIA AND SNOW AMOUNTS MAY NOT BE HIGH ENOUGH TO CAUSE A LARGE IMPACT. CONDITIONS WILL HAVE TO BE MONITORED CLOSELY THIS EVENING FOR A POSSIBLE QUICK UPGRADE WITH THE 9PM TO 3AM TIME FRAME THE MAIN PERIOD OF CONCERN. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 343 PM CDT SUN APR 13 2014 THE MAIN STORIES THROUGH THIS WEEK ARE WITH THE POTENTIAL ACCUMULATING SNOW ON TUESDAY NIGHT/WEDNESDAY AND ANOTHER SYSTEM LATER IN THE WEEK. MORE FOCUS WENT INTO THE TUESDAY NIGHT/WEDNESDAY SYSTEM SINCE THERE IS QUITE A BIT OF UNCERTAINTY WITH THE LATE WEEK SYSTEM. THE 13.12Z NAM/GFS DEVELOPS A BAND OF SNOW ACROSS NORTHERN WISCONSIN LATE TUESDAY NIGHT WHILE THE 13.12Z ECMWF KEEPS US DRY. SOME ACCUMULATING SNOW IS LIKELY IN THE NAM/GFS SCENARIOS THOUGH ENOUGH UNCERTAINTY IS THERE THANKS TO THE ECMWF. IT LOOKS LIKE WE GET WARM SECTORED ON WEDNESDAY AS THE SYSTEM STALLS OUT WITH THE PRECIPITATION SETTING UP FROM UPPER MICHIGAN DOWN THROUGH CENTRAL IOWA ON THURSDAY. THE 13.12Z GFS THEN SPINS UP A POTENT SYSTEM FOR FRIDAY THAT TRACKS THROUGH WISCONSIN WHILE EH ECMWF HARDLY HAS A LOW DEVELOPING. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1140 PM CDT SUN APR 13 2014 AS SHORT WAVE CONTINUES TO PUSH EAST TONIGHT...PRECIPITATION HAS BEEN WAINING. COLUMN HAS BEEN COOLING AS WELL ALLOWING RAIN TO CHANGE OVER TO SNOW FROM WEST TO EAST. BUT OVERALL CONDITIONS HAVE BEEN IMPROVING WITH LESS LIFR AND MORE MVFR BEING OBSERVED AROUND THE AREA. OVER THE NEXT FEW HOURS...EXPECT RAIN AND SNOW TO END. BEFORE THEN COULD SEE A DEFORMATION ZONE DEVELOP AND BRING ONE MORE ROUND OF SNOW TO KRST BEFORE ENDING. MVFR CEILINGS EXPECTED TOWARDS DAYBREAK AND THEN AS SYSTEM EXITS...COULD SEE VFR FOR MUCH OF THE DAY. A BIT UNSURE ON WHAT CLOUDS WILL DO MONDAY AFTERNOON AS UPPER TROUGH SETTLES IN. COULD SEE SOME LOW CLOUD DEVELOPMENT GIVEN MID APRIL SUN BUT AM BANKING THAT MID LEVEL CLOUDS AROUND WILL BE ABOUT IT. STIFF NORTHWEST WINDS SHOULD ALSO SUBSIDE AS WEATHER SYSTEM EXITS BY MONDAY EVENING. && .HYDROLOGY... ISSUED AT 343 PM CDT SUN APR 13 2014 WITH MODERATE TO AT TIMES HEAVY RAIN FALLING INTO TONIGHT...WILL KEEP THE FLOOD WATCH GOING FOR NORTHEAST IOWA AND SOUTHWEST WISCONSIN. WITH 1 TO 3 INCHES OF RAIN FALLING LAST NIGHT ACROSS THIS AREA AND ANOTHER 1 TO 2 INCHES POSSIBLE...SAW NO NEED TO DROP IT. THERE DOES NOT APPEAR TO BE MUCH INSTABILITY THAT MAKES IT UP IN THE REGION THIS AFTERNOON INTO TONIGHT...SO MOST OF THE RAIN SHOULD NOT FALL AT A GREAT ENOUGH OF A RATE TO PROMPT FLASH FLOODING. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...FLOOD WATCH UNTIL 1 AM CDT MONDAY FOR WIZ043-044-053>055-061. MN...NONE. IA...FLOOD WATCH UNTIL 1 AM CDT MONDAY FOR IAZ030. && $$ SHORT TERM...HALBACH LONG TERM...HALBACH AVIATION...SHEA HYDROLOGY...HALBACH
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1137 PM MDT SUN APR 13 2014 .UPDATE... ISSUED AT 1133 PM MDT SUN APR 13 2014 WENT AHEAD AND LET THE WINTER HIGHLIGHTS EXPIRE AT 11 PM THIS EVENING. LATEST RADAR SHOWING ONLY LIGHT RETURNS WITH THE AERIAL COVERAGE SHRINKING FAIRLY QUICKLY. UPDATES HAVE BEEN SENT. UPDATE ISSUED AT 538 PM MDT SUN APR 13 2014 WENT AHEAD AND EXTENDED WINTER HEADLINES FOR THE I-80 CORRIDOR THROUGH 11 PM THIS EVENING. HAVE ANOTHER BAND OF SNOW MOVING NORTHEAST OUT OF COLORADO ON IR IMAGERY. MAY NOT LAST THROUGH 11 PM...BUT IT DOES LOOK LIKE ACCUMULATING SNOW WILL CONTINUE AT LEAST THROUGH MID EVENING BEFORE EASING SOME. SOME MODEL GUIDANCE SUGGESTING THAT SNOW COULD LAST LONGER. WILL RE-EVALUATE IN A COUPLE HOURS. DID GO AHEAD AND EXPIRE OUR NORTHERN WINTER HEADLINES AS RADAR MOSAIC SHOWING SNOW COVERAGE DECREASING. UPDATES HAVE BEEN SENT. && .SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT) ISSUED AT 240 PM MDT SUN APR 13 2014 SATELLITE PIX SHOW WELL-DEFINED CIRCULATION SPINNING THRU UTAH WITH A JET STREAK BEGINNING TO ROUND ITS BASE. THE RELATIVE LULL THIS MORNING ACROSS MUCH OF THE AREA WAS A RESULT OF A BREAK BETWEEN A DEPARTING SHORTWAVE MOVING INTO THE CENTRAL PLAINS AND THE NEXT ONE OVR UTAH. AT 20Z...THE NEXT LINE OF ENHANCED CLOUD- TOPS WERE JUST BEGINNING TO ENTER SRN ALBANY AND LARAMIE COUNTIES...WITH SIMILAR TRENDS NOTICED ON KCYS 88D RETURNS. SO WILL SEE SNOW RATES PICK UP AGAIN ESPECIALLY ACROSS EXTREME SE WYOMING THRU AT LEAST SUNSET. AS WAS FEARED...THE HIGH APRIL SUN- ANGLE HAS RESULTED IN SUBSTANTIAL MELTING ON AREA ROADWAYS... WHICH HAS LESSENED IMPACT SOME. HOWEVER A FEW ROAD CLOSURES HAVE OCCURRED ALONG PORTIONS OF INTERSTATE 80. AN ADDITIONAL 1 TO 3 INCHES OF ACCUMULATION CAN BE EXPECTED THRU EARLY THIS EVENING. SO WILL KEEP THE HIGHLIGHT PACKAGE UNCHANGED FOR NOW AND CONTINUE TO RE-EVALUATE TRENDS THRU THE REST OF THE AFTERNOON. LATEST MODELS CONTINUE TO LINGER SNOW INTO THIS EVENING... HOWEVER RATES SHOULD BE MUCH LESS AS BEST LIFT SHIFTS SOUTH OUT OF THE CWFA. ANY LINGERING LIGHT SNOW WILL GRADUALLY END THIS EVENING...WITH DRYING CONDITIONS THEN OVERNIGHT. OTHERWISE...OVERNIGHT LOWS WILL FALL INTO THE TEENS ACROSS SOUTHEAST WYOMING...WITH LOW 20S OVR THE PANHANDLE. HEIGHTS BUILD RAPIDLY BEHIND THE DEPARTING SHORTWAVE ON MONDAY...YIELDING DRY AND MOSTLY SUNNY CONDITIONS. NORTHWEST WINDS WILL BE BREEZY ESPECIALLY OVER THE EASTERN PLAINS WHERE GUSTS OF 25 TO 30 MPH ARE EXPECTED. TEMPERATURES WILL REBOUND SOME ON MONDAY TOO...ALTHOUGH WILL BE TEMPERED BY TODAYS SNOW. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 240 PM MDT SUN APR 13 2014 TUESDAY...QUICK WARMUP ON TAP AS OUR FLOW ALOFT BECOMES ZONAL...WEST TO EAST...AHEAD OF THE PROGRESSIVE LOW AMPLITUDE SHORTWAVE TROUGH ALOFT OVER MONTANA...AIDING THE DEVELOPMENT OF SURFACE LOW PRESSURE OVER WESTERN SOUTH DAKOTA...AND PRODUCING DOWNSLOPE KATABATIC WARMING ACROSS OUR COUNTIES WITH MAXIMUM TEMPERATURES OVER OUR COUNTIES IN THE 50S WEST OF INTERSTATE 25...AND UPPER 50S TO MID 60S ELSEWHERE. WEDNESDAY...ANOTHER RELATIVELY STRONG CANADIAN ORIGIN COLD FRONTAL PASSAGE OCCURS EARLY IN THE DAY...WITH TEMPERATURES LIKELY STEADY OR SLOWLY FALLING DURING THE DAY. THIS SHORTWAVE TROUGH WILL NOT HAVE AS MUCH MOISTURE AS OUR CURRENT SUNDAY STORM...AND LESS MESOSCALE AND DYNAMIC LIFT...THUS 30 TO 60 PERCENT POPS AT LOWER ELEVATIONS WITH 80 TO 100 PERCENT POPS DUE TO FAVORABLE OROGRAPHICS OVER THE NORTHERN LARAMIE...SNOWY AND SIERRA MADRE RANGES. THURSDAY...DRYING OUT PERIOD IN THE WAKE OF THE SHORTWAVE TROUGH ALOFT WITH A FEW LEFTOVER SHOWERS OVER THE MOUNTAINS. CONTINUED RELATIVELY COOL WITH SURFACE HIGH PRESSURE KEEPING THE COLD AIR REINFORCED OVER THE CENTRAL PLAINS STATES. FRIDAY...SPRINGTIME IN THE ROCKIES CONTINUES WITH A MILD SPRING DAY TO END OUR TRADITIONAL WORKWEEK...AS TRANSITORY RIDGING ALOFT MOVES OVER THE ROCKIES...INDUCING STRENGTHENING SURFACE LEE TROUGHING AND DOWNSLOPE WARMING AIDING HIGH TEMPERATURES SOARING INTO THE 50S... AND PERHAPS EVEN WARMER IF THE WARMER ECMWF CAN BE BELIEVED...AS IT SHOWS 1000-500 MB THICKNESSES NEAR 5640 METERS WITH 700 MB TEMPERATURES NEAR 7 CELSIUS. SATURDAY...ANOTHER MILD DAY UNDER NORTHWEST FLOW ALOFT AND RELATIVELY HIGH THICKNESSES AND 700 MB TEMPERATURES. SUNDAY...EASTER SUNDAY LOOKS MILD AND DRY WITH NORTHWEST FLOW ALOFT AND A RIDGE ALOFT OVERHEAD...AND EASTER SUNRISE SERVICES SHOULD BE PLEASANT FOR OUTDOOR ACTIVITIES WITH MINIMAL CLOUD COVER AND RELATIVELY MILD TEMPERATURES ABOVE FREEZING TO START THE DAY. .AVIATION...MOUNTAINS OBSCURED. WIDESPREAD IFR AND MVFR THROUGH THIS AFTERNOON IN SNOW AND LOW CLOUDS...THEN AREAS OF FOG AND LOW CLOUDS OVERNIGHT PRODUCING IFR AND MVFR...WITH VFR DEVELOPING LATE TONIGHT AND MONDAY MORNING FROM NORTH TO SOUTH. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY EVENING) ISSUED AT 1133 PM MDT SUN APR 13 2014 ONLY TROUBLE AIRFIELD AT THIS TIME LOOKS TO BE LARAMIE WITH IFR VISIBILITIES IN SNOW. THE LATEST HRRR FORECAST HAS IFR CONDITIONS HANGING IN AROUND KLAR FOR A FEW MORE HOURS BEFORE DISSIPATING AFTER 10Z OR SO. VFR CONDITIONS ALL AIRPORTS AFTER SUNRISE MONDAY. && .FIRE WEATHER... ISSUED AT 240 PM MDT SUN APR 13 2014 NO FIRE WEATHER CONCERNS THROUGH EARLY NEXT WEEK AS FRESH MOISTURE AND SNOW COVER FROM TODAYS SNOWSTORM LINGERS. SNOW-COVER WILL ALSO KEEP TEMPERATURES COOLER THROUGH EARLY IN THE WEEK...WHICH WILL KEEP HUMIDITIES UP. THE NEXT CHANCE OF PRECIPITATION RETURNS TO THE DISTRICTS ON WEDNESDAY. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...NONE. NE...NONE. && $$ UPDATE...CLAYCOMB SHORT TERM...HAHN LONG TERM...RUBIN AVIATION...CLAYCOMB FIRE WEATHER...HAHN
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
418 AM CDT WED APR 16 2014 .SYNOPSIS... ISSUED AT 406 AM CDT WED APR 16 2014 HIGH PRESSURE RIDGE HAS MOVED INTO THE OHIO VLY WHILE A 998 MB SFC CYCLONE WAS LOCATED SOUTH OF PIERRE SD AT 07Z. SOUTHEAST WINDS ARE STRENGTHENING OVER THE AREA IN TIGHTENING PRESSURE GRADIENT RESULTING IN STEADY TO RISING TEMPS. PATTERN ALOFT FEATURES FAST SEMI-ZONAL FLOW OVER REGION AHEAD OF SHORTWAVE TRAVERSING NORTHERN ROCKIES. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 406 AM CDT WED APR 16 2014 CRITICAL FIRE WEATHER AND WIND ADVISORY CONCERNS DOMINATE THE FCST. SFC CYCLONE OVER SD WILL MOVE EAST INTO WI BY EARLY THURSDAY AM. TRAILING COLD FRONT WILL MOVE INTO CWA LATER THIS EVENING AND MOVE EAST AND SHOULD BE NEAR OR JUST EAST OF MISSISSIPPI RIVER BY 12Z THURSDAY. WARM SECTOR OF SYSTEM IS MOISTURE STARVED AND THUS MOST OF PCPN THAT OCCURS DURING PERIOD WILL BE RIGHT AHEAD AND NORTH OF SFC CYCLONE TRACK. WILL THOUGH HAVE SMALL CHCS FOR LIGHT RAIN WITH FRONT TONIGHT MAINLY NORTHEAST IA BEING IN CLOSER PROXIMITY TO PV ANOMALY AND VORTICITY ADVECTION. VERY STRONG LOW LEVEL JET WITH 850 MB WINDS OF 50-60 KTS TO FOCUS MAINLY WEST OF CWA THIS AM THEN SHIFT INTO AREAS WEST OF MISSISSIPPI RIVER THIS AFTN BUT WEAKENING TO NEAR 40 KTS. NONETHELESS...TIGHTENING PRESSURE GRADIENT AND DEEP MIXING TAPPING STRONGER WINDS ALOFT SHOULD GENERATE SUSTAINED SOUTHEAST TO SOUTH WINDS AT 20-25 KTS WITH GUSTS AROUND 35 KTS... CLOSE TO WIND ADVISORY CRITERIA WHICH WILL NEED TO BE MONITORED IN CASE AN ADVISORY BECOMES NEEDED...BUT ENOUGH UNCERTAINTY WITH CLOUDS AND POTENTIAL IMPACTS ON MIXING AND NOTED WEAKENING TRENDS ON WINDS ALOFT FROM LATEST RUC AND NAM TO HOLD OFF ON ISSUING ATTM. STRONG WINDS WILL AID IN ELEVATED FIRE DANGER TODAY...WITH MAIN CHALLENGE BEING LOW LEVEL MOISTURE AND MODELS HANDLING WHICH WILL LOOM LARGE AS TO WHETHER RED FLAG WARNING CRITERIA IS ACHIEVED IN SOME AREAS. DEEP MIXING TO AT OR ABOVE 800 MB IF REALIZED FROM NAM/RUC SOUNDINGS WOULD YIELD SUBSTANTIAL DROP IN DEWPTS INTO THE TEENS TO LOWER 20S ALL BUT FAR WESTERN CWA THIS AFTN. AND THESE LOW DEWPTS CERTAINTLY SHOW UP IN LOOKING BACK AT UPSTREAM OBS IN SIMILAR REGIME YSTDY. UNCERTAINTY WITH HOW MUCH RECENT HEAVY RAINS AND CONTINUED GREENING UP TO IMPACT OR OFFSET DRYING ATTENDANT TO DEEP MIXING. THIS IS DISCUSSED FURTHER IN FIRE WEATHER SECTION BELOW. HIGHS TODAY WITH MIXING AND PROGGED LOW LEVEL THICKNESS AND VERIFICATION FROM YSTDY ALONG WITH BOUTS OF MID/HIGH CLOUDINESS SUPPORT LOWERING MAXES FEW DEGS ESPECIALLY NORTHEAST 1/3-1/2. OVERALL... VERIFICATION SUPPORTS HIGHS RANGING FROM 50-55F NORTHEAST TO LOWER 60S SOUTHWEST. TEMPS MILD MOST OF TONIGHT HELD UP BY BREEZY SOUTH/SOUTHWEST WINDS WITH TEMPS FALLING LATE WITH FRONTAL PASSAGE WITH MID 30S WEST/NORTHWEST TO LOWER 40S EAST/SOUTHEAST. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 406 AM CDT WED APR 16 2014 FORECAST FOCUS IN THE EXTENDED IS ON CONTINUED BELOW NORMAL TEMPERATURES THROUGH THE REST OF THE WORK WEEK WITH SMALL PCPN CHANCES ACROSS THE SOUTHEAST THURSDAY NIGHT/FRIDAY MORNING. TEMPERATURES TO RETURN TO NORMAL THIS WEEKEND AND POSSIBLY ABOVE NORMAL EARLY NEXT WEEK. THURSDAY...WEAK COLD FRONT TO BE JUST EAST OF CWA IN THE MORNING WITH PARENT LOW LIFTING NORTHEAST INTO THE GREAT LAKES. LINGERING CLOUDS...WEST WINDS...AND MIXING TO AROUND 900MB WILL KEEP TEMPERATURES WELL BELOW NORMAL WITH AFTERNOON READINGS IN THE UPPER 40S NORTH TO MIDDLE 50S SOUTH. ONE CONCERN IS CLOUD TRENDS AND IF CLOUDS CLEAR OUT...THAN FORECAST MAX TEMPS MAY BE A FEW DEGREES TOO COLD. THURSDAY NIGHT-FRIDAY...SHORTWAVE TO TRACK OVER THE SOUTHERN PLAINS LIFTING NORTHEAST NEAR THE CWA AROUND MIDNIGHT. LOW LEVEL CONVERGENCE AND MOISTURE TRANSPORT INCREASES ACROSS THE FAR SOUTHEAST WITH LIGHT RAIN SHOWERS BREAKING OUT MAINLY SOUTH AND EAST OF A LINE FROM KIRKSVILLE MISSOURI TO PRINCETON ILLINOIS. MOISTURE AVAILABILITY IS VERY LIMITED SO QPF AMOUNTS WILL BE A FEW HUNDREDTHS OF AN INCH. ONE THING OF NOTE IS THE LATEST NAM SOLUTION HAS A NON-EVENT FOR THIS PERIOD WHICH WAS MUCH DIFFERENT THAN ITS PREVIOUS RUN. ANOTHER VERY INTERESTING THING IS THAT THE NEW 00Z NAM/GFS BOTH HAVE A SHORTWAVE COMING DOWN FROM CANADA IMPACTING THE CWA WITH CLOUDS AND PCPN CHANCES FRIDAY. THE NON-AMERICAN SOLUTIONS (ECMWF/GEM/UKMET) ALL SAY OTHERWISE AND HAVE DRY FORECASTS. SIDED WITH THE NON-AMERICAN SOLUTIONS GIVEN THAT THE NAM/GFS HAVE BEEN NOTORIOUSLY TOO MOIST IN THE LOW LEVELS THIS SPRING. HIGH TEMPERATURES FRIDAY TO BE A LITTLE WARMER THAN THURSDAY BUT STILL BELOW NORMAL. THIS WEEKEND...MODELS CONTINUE TO SHOW A STORM SYSTEM TRACKING ACROSS SOUTHERN CANADA WITH A COLD FRONT MOVING ACROSS THE MIDWEST. AHEAD OF THIS FRONT...TEMPERATURES WILL WARM NICELY WITH 85H TEMPS PROGGED TO BE IN THE +6 TO 10C RANGE BY 00Z SUNDAY. HIGHS OVER THE WEEKEND TO BE IN UPPER 50S/LOW 60S SATURDAY AND IN THE 60S AREA WIDE ON SUNDAY. FORCING AND LOW LEVEL MOISTURE INCREASES SUNDAY AHEAD OF COLD FRONT WITH LIGHT TO POSSIBLY MODERATE RAIN FALLING SOMETIME DURING THE DAY. MODEL CONSENSUS HAS CHANCE POPS AT THIS TIME FOR SUNDAY. EARLY NEXT WEEK...WARM AND DRY CONDITIONS WILL BE FOUND AS HIGH PRESSURE DRIFTS ACROSS THE MIDWEST. TEMPERATURES TO AVERAGE ABOVE NORMAL WITH HIGHS WELL INTO THE 60S AND LOWER 70S. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 1137 PM CDT TUE APR 15 2014 STRONG SOUTH WINDS WILL DEVELOP BY WEDNESDAY MORNING AS LOW PRESSURE MOVES FROM SOUTH DAKOTA INTO NORTH CENTRAL IOWA BY LATE WEDNESDAY AFTERNOON. SOUTH WINDS AT 20 TO 25 KTS GUSTING TO AROUND 30KTS ARE EXPECTED 12Z-15Z WITH SPEEDS INCREASING TO AROUND 25KTS WITH GUSTS AROUND 35KTS BY 17Z AND CONTINUING THROUGH THE AFTERNOON. THERE REMAINS A CONCERN ABOUT THE POTENTIAL FOR LOW LEVEL WIND SHEAR LATE TONIGHT AS SOUTH WINDS AROUND 2KFT INCREASE TO 40 TO 50KTS. SINCE THE INCREASE IN SPEED WITH HEIGHT WILL BE GRADUAL AND WINDS WILL BE UNIDIRECTIONAL THROUGH THIS LAYER...THE THREAT FOR SIGNIFICANT SHEAR STILL LOOKS MARGINAL. WEDNESDAY EVENING THE LOW WILL LIFT NORTHEAST INTO WISCONSIN...DRAGGING A COLD FRONT THROUGH CENTRAL IOWA. A FEW SHOWERS JUST AHEAD OF THE FRONT MAY MAKE IT INTO THE KCID VICINITY JUST BEFORE 06Z. WINDS WILL ALSO BE DECREASING AHEAD OF THE FRONT...BUT SHOULD REMAIN GUSTY. && .FIRE WEATHER... ISSUED AT 406 AM CDT WED APR 16 2014 SOUTHEAST TO SOUTH WINDS WILL INCREASE TO NEAR ADVISORY CRITERIA AT TIMES LATE THIS MORNING THROUGH AFTERNOON WITH SUSTAINED SPEEDS AT 20-30 MPH AND GUSTS TO NEAR 40 MPH. MAIN QUESTION/CONCERN IS WITH SURFACE DEW POINTS AND SUBSEQUENT RELATIVE HUMIDITY VALUES. MODEL GUIDANCE SUPPORTIVE OF DEW POINTS IN THE 20S TO LOWER 30S WHICH COMBINED WITH TEMPS IN THE 50S TO LOWER 60S WOULD YIELD RELATIVE HUMIDITY VALUES MAINLY IN THE 30S. HOWEVER...DEEP MIXING AIDED BY SOUTHEAST FETCH OFF DEPARTING HIGH PRESSURE RIDGE WOULD SUPPORT SUBSTANTIALLY LOWER DEW POINTS AND RELATIVE HUMIDITY VALUES IN THE TEENS AND 20S. ALSO ADDING TO THE UNCERTAINTY IS DEGREE OF IMPACTS IF ANY OF RECENT HEAVY RAINS AND CONTINUED GREENING UP. IF THE LOWER VALUES OCCUR THEN IT WOULD LEAD TO VERY HIGH TO EXTREME GRASSLAND FIRE DANGER INDEX VALUES AND LIKELY NECESSITATE RED FLAG WARNING PORTIONS OF AREA. ENOUGH UNCERTAINTY PRECLUDES ISSUANCE OF RED FLAG WARNING AT THIS TIME... BUT WILL NEED TO MONITOR DEW POINT AND RELATIVE HUMIDITY LEVELS CAREFULLY FOR POTENTIAL OF NEEDING HEADLINE. FIRE DANGER ELEVATED TO POSSIBLY HIGH OVER DRY GRASSES AND CURED VEGETATION. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ SYNOPSIS...05 SHORT TERM...05 LONG TERM...GROSS AVIATION...DLF FIRE WEATHER...05
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
525 AM EDT WED APR 16 2014 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 531 PM EDT TUE APR 15 2014 BIGGEST FORECAST CONCERNS FOR SHORT TERM FOCUS ON WINTER STORM HEADLINES STARTING WEDNESDAY AND CONTINUING INTO THURSDAY. WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH FROM HUDSON BAY THROUGH THE CENTRAL GREAT LAKES INTO THE GULF COAST STATES. INSTABILITY ASSOC WITH THIS TROUGH HAS SUPPORTED SOME DIURNAL -SHSN ACROSS INLAND AREAS THIS AFTERNOON. THE SHORTWAVE MOVING IN OFF THE PAC NW WILL BE THE FEATURE OF INTEREST IN THE SHORT TERM AS IT DEVELOPS A DEEPENING STORM SYSTEM OVER THE NRN PLAINS LATE TONIGHT AND BRINGS IT TOWARD THE WRN GREAT LAKES LATE WED INTO WED NIGHT. TONIGHT...ANY LEFTOVER DIURNAL SHSN OVER S CNTRL UPPER MI WILL DIMINISH EARLY THIS EVENING AS PARTLY CLOUDY SKIES AND LIGHT WINDS ALLOW TEMPS TO FALL INTO THE LOW SINGLE DIGITS OVER TYPICAL COLD SPOTS FAR EAST TO 15 TO 20F RANGE FOR DOWNSLOPING AREAS ALONG LAKE SUPERIOR FAR WEST AND AREAS CLOSE TO BAY OF GREEN BAY. TEMPS MAY CLIMB LATE AS CLOUDS INCREASE AHEAD OF THE APPROACHING LOW PRESSURE SYSTEM. WAA LIGHT SNOW WITH INCREASING 280K-290K ISENTROPIC LIFT IS EXPECTED TO REMAIN MAINLY WEST OF UPPER MI BUT MAY SLIDE INTO THE FAR WEST LATE. WEDNESDAY...MODELS GENERALLY IN AGREEMENT SHOWING SHORTWAVE OF INTEREST AND ASSOC DEEPENING SFC LOW OVER SE SOUTH DAKOTA AROUND 12Z THEN DIFFER ON HOW QUICKLY THEY LIFT THIS LOW ENE TOWARD THE UPPER GREAT LAKES. MOST OF 12Z MODELS GENERALLY TRENDING SLIGHTLY SLOWER AND FARTHER SE THAN 06Z RUNS WITH TRACK OF SFC LOW. MODELS INDICATE WARM AIR ADVECTION AND ISENTROPIC ASCENT ALONG AND AHEAD OF THE LOW AND INVERTED SFC TROUGH SHOULD SUPPORT EXPANDING SNOW SHIELD FM CNTRL MINNESOTA INTO NORTHWEST WI LATE TONIGHT THROUGH DAYBREAK ON WEDNESDAY. THIS SNOW SHIELD WILL THEN SPREAD INTO WEST AND CENTRAL UPPER MI DURING THE DAY ON WEDNESDAY. AS SFC TROUGH EDGES CLOSER TO UPR MICHIGAN WED AFTN ISENTROPIC ASCENT BECOMES MAXIMIZED ON 285-290K SFCS ACROSS UPR MICHIGAN FROM 15Z INTO WED EVENING. GFS REMAINS QUICKEST OF 12Z MODELS WHILE THE ECMWF IS THE SLOWEST. THE NAM AND REGIONAL GEM FALL SOMEWHERE BTWN THESE SOLNS. H7 MIXING RATIOS IN 2.5-3 G/KG RANGE SUGGESTS 12 HOUR SNOW AMOUNTS 4-6 INCHES OVER MAINLY THE WEST HALF COUNTIES. IT/S POSSIBLE ACTUAL SNOW AMOUNTS ON WED COULD BE HELD DOWN SOME AS SNOW ARRIVES DURING THE DAYTIME WHEN INSOLATION COULD LIMIT ACCUMS ESPECIALLY ON HIGHER TRAFFIC/TRAVELLED ROADS. CROSS SECTIONS SUGGEST POSSIBILITY OF HEAVIER BANDED SNOWFALL OVER WESTERN COUNTIES WITH NEG EPV ABOVE FAIRLY STRONG 7H FGEN FORCING SO THIS COULD ADD A FEW INCHES TO THE 4-6 INCH TOTALS RENDERED SOLELY FM ISENTROPIC ASCENT. WITH ALL ABOVE FACTORS TAKEN INTO CONSIDERATION...HAVE DECIDED TO UPGRADE WATCHES OVER THE WEST HALF COUNTIES TO WARNINGS FROM MQT-DICKINSON WESTWARD. GENERALLY STARTED WARNINGS ON WED FM 14Z SOUTH TO 16Z NORTH. ALSO MOVED THE AXIS OF HEAVIER PCPN/SNOWFALL SLIGHTLY FARTHER EASTWARD BASED ON 12Z MODEL TRENDS WITH SNOWFALL AMOUNTS ON WED RANGING FM 3 TO 5 INCHES OVER THE NW CWA TO 4-7 INCHES OVER THE FAR SW CWA ALONG THE WI BDR. WENT WITH ADVISORIES FOR MNM...DELTA AND ALGER COUNTIES WHERE 2-4 INCH AMOUNTS WILL BE MORE COMMON ON WED WITH MUCH OF THE SNOW FALLING IN THE AFTERNOON HRS. FARTHER EAST OVER SCHOOLCRAFT AND LUCE COUNTIES...LOW-LVL DRY AIRMASS INITIALLY IN PLACE FROM LINGERING SFC RDG AXIS WILL TAKE A BIT LONGER TO MOISTEN FM ISENTROPIC ASCENT SO ONLY EXPECT GENERALLY 1-2 INCHES OF SNOW THERE AND WILL HOLD OFF ON ANY HEADLINE THERE FOR NOW. IF TONIGHT/S MODEL RUNS CONTINUE TO TREND EASTWARD MAY NEED TO CONSIDER POSSIBILITY OF ADDING MNM AND POSSIBLY DELTA INTO WARNING. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 514 AM EDT WED APR 16 2014 THURSDAY...WITH THE SLOWER MODEL TREND...THE SHORTWAVE OVER NRN WI AND ASSOCIATED 700-500 QVECTOR CONV AND 290K-295 ISENTROPIC LIFT WILL CONTINUE TO SUPPORT MODERATE SNOW IN THE MORNING...WITH ADDITIONAL ACCUMULATIONS IN THE 1 TO 3 INCH RANGE...GREATEST OVER THE NW HALF. THE STRONGER DYNAMICS AND PCPN WILL QUICKLY LIFT TO THE NORTHEAST BY AFTERNOON WITH LITTLE ADDITIONAL SNOW. THERE MAY ALSO BE A MIX OF LIGHT RAIN OVER THE SOUTH AND EAST PORTIONS OF THE CWA. THURSDAY NIGHT...MOIST LOW LEVEL CYCLONIC FLOW BEHIND THE DEPARTING LOW WILL RESULT IN MOSTLY CLOUDY SKIES AND SHOULD KEEP MIN TEMPS IN THE LOW TO MID 20S. FRIDAY...IF CLOUDS DO CLEAR OUT IN SOME AREAS THU NIGHT...EXPECT BKN DIURNAL CU DEVELOPMENT FRI UNDER THE MID LEVEL TROF AND ASSOCIATED THERMAL TROF WITH 850/700 MB TEMPS AROUND -10C/-15C. ALTHOUGH THE STEEP LOW LEVEL LAPSE RATES COULD SUPPORT SOME FLURRIES...NO ACCUMULATION IS EXPECTED. FRI HIGHS WILL BE IN THE 30S NORTH WITH A COLD WIND OFF THE ICE TO THE 40S S. WITH CLOUDS CLEARING OUT FRI NIGHT...IT WILL BE A COLD NIGHT WITH HIGH PRES STILL OVER THE AREA. FAVORED THE LOWER SIDE OF GUIDANCE WITH SOME TEENS OVER THE W WHERE WINDS WILL BE LIGHTEST. COULD BE CONSIDERABLY COLDER ACROSS ALL OF THE INTERIOR IF SKIES CLEAR EARLY AND STAY THAT WAY FOR A GOOD PART OF THE NIGHT. SAT INTO SUN...A SHORTWAVE TROUGH OVER THE PAC NW THU WILL REACH NRN ONTARIO SAT NIGHT INTO SUN. THE GEM AND ECMWF REMAINED MORE PROGRESSIVE AND STRONGER WITH THE NRN PORTION OF THE SHRTWV...DRAGGING THE FRONTAL SYSTEM THROUGH UPPER MI FASTER THAN THE GFS. LOW LEVEL TEMPS WILL BE WARM ENOUGH FOR MAINLY RAIN. EXPECT THE GREATEST RAIN CHANCE SAT NIGHT WITH SOME CLEARING POSSIBLE SUN AS DRIER AIR MOVES IN FROM THE WEST. TEMPERATURES SHOULD CLIMB BACK INTO THE LOWER TO MID 40S BY SUN AFTERNOON. MON/TUE...THE MODELS SUGGEST THAT THE PATTERN WILL AMPLIFY AS A TROUGH DIGS INTO THE WEST COAST. AS A RESULT THE NRN LAKES WILL BE ON THE EDGE OF THE WARMER AIR AS A RIDGE BUILDS OVER THE PLAINS. TEMPS SHOULD CLIMB BACK TO NEAR NORMAL WITH HIGHS IN THE UPPER 40S AND LOWER 50S WITH MIN READINGS IN THE LOWER 30S. SOME LIGHT RAIN MAY BE POSSIBLE WITH ANY WEAK SHRTWVS EMBEDDED IN THE WNW FLOW THROUGH THE REGION. HOWEVER...ANY AMOUNTS WOULD BE VERY LIGHT. SO...ONLY SLIGHT CHANCE POPS SEEM ON TRACK. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 133 AM EDT WED APR 16 2014 LIGHT WINDS WILL PERSIST THROUGH THE NIGHT AS HIGH PRESSURE MOVES THROUGH THE REGION. THEN AN APPROACHING STORM SYSTEM WILL BRING INCREASING CLOUDS AND SNOW TO THE AREA. KIWD WILL SEE THE IMPACTS FIRST...WITH IFR VSBYS DEVELOPING THERE BY MIDDAY IN LIGHT TO MODERATE SNOW. THE SNOW WILL THEN SPREAD TO KCMX AND KSAW THROUGH THE REMAINDER OF THE DAY. CIGS TO LOWER DURING THE DAY WITH IFR CONDITIONS DEVELOPING AS THE SYSTEM CLOSES IN ON THE AREA AND PERSISTING THROUGH THE END OF THE FORECAST. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 524 AM EDT WED APR 16 2014 AN APPROACHING LOW PRESSURE SYSTEM FROM THE PLAINS WILL RESULT IN INCREASING EAST TO NORTHEAST WINDS TODAY WITH GALES FOR FAR WRN LAKE SUPERIOR THIS AFTERNOON INTO THU MORNING MORNING AS WINDS ARE ENHANCED DUE TO CHANNELING AND TERRAIN EFFECTS. WINDS SHIFT TO THE NORTH-NORTHWEST TO 25 KTS BY THURSDAY AFTERNOON AS THE LOW WEAKENS WHILE MOVING OVER ERN LK SUPERIOR. EXPECT WINDS STAY BLO 20 KTS FOR THE REST OF THE FORECAST PERIOD. && .HYDROLOGY... ISSUED AT 531 PM EDT TUE APR 15 2014 RECENT COLDER WEATHER AND CONTINUATION OF COLDER WEATHER FOR THE NEXT FEW DAYS WILL RESULT IN SLOW RUNOFF OF MELTING SNOW. THUS... RIVER LEVELS SHOULD NOT SHOW ANY SIGNIFICANT FLUCTUATIONS. HOWEVER...ICE JAMS COULD BE AN ISSUE AS THEY HAVE BEEN IN SOME AREAS. HOWEVER...DIMINISHED RUNOFF SHOULD REDUCE THE POTENTIAL FOR ADDITIONAL ICE JAMS. WIDESPREAD PRECIPITATION IS IN THE FORECAST FOR WEDNESDAY THROUGH THURSDAY MORNING WITH THE POTENTIAL FOR 0.50 TO 1.25 INCHES OF LIQUID EQUIVALENT PRECIPITATION...GREATEST OVER THE W HALF OF UPPER MICHIGAN. THIS PRECIP ADDED TO EXISTING SNOWPACK WITH WATER EQUIVALENT OF 4-9 INCHES WILL RESULT IN ANOTHER PERIOD OF SNOWMELT RUNOFF/RIVER RISES AND POSSIBLE ICE JAMS ONCE WARMER TEMPERATURES ARRIVE NEXT WEEK. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... WINTER WEATHER ADVISORY FROM 2 PM THIS AFTERNOON TO NOON EDT THURSDAY FOR MIZ006-013. WINTER STORM WARNING FROM NOON TODAY TO 11 AM EDT THURSDAY FOR MIZ004-084. WINTER STORM WARNING FROM NOON TODAY TO NOON EDT THURSDAY FOR MIZ005. WINTER STORM WARNING FROM 11 AM EDT /10 AM CDT/ THIS MORNING TO 11 AM EDT /10 AM CDT/ THURSDAY FOR MIZ002-009>011. WINTER STORM WARNING FROM 2 PM THIS AFTERNOON TO NOON EDT THURSDAY FOR MIZ001-003. WINTER WEATHER ADVISORY FROM 9 AM THIS MORNING TO 10 AM CDT THURSDAY FOR MIZ012. LAKE SUPERIOR... GALE WARNING FROM 6 PM EDT /5 PM CDT/ THIS EVENING TO 6 AM EDT /5 AM CDT/ THURSDAY FOR LSZ162. LAKE MICHIGAN... NONE. && $$ SHORT TERM...VOSS LONG TERM...JLB AVIATION...RJT MARINE...JLB HYDROLOGY...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
515 AM EDT WED APR 16 2014 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 531 PM EDT TUE APR 15 2014 BIGGEST FORECAST CONCERNS FOR SHORT TERM FOCUS ON WINTER STORM HEADLINES STARTING WEDNESDAY AND CONTINUING INTO THURSDAY. WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH FROM HUDSON BAY THROUGH THE CENTRAL GREAT LAKES INTO THE GULF COAST STATES. INSTABILITY ASSOC WITH THIS TROUGH HAS SUPPORTED SOME DIURNAL -SHSN ACROSS INLAND AREAS THIS AFTERNOON. THE SHORTWAVE MOVING IN OFF THE PAC NW WILL BE THE FEATURE OF INTEREST IN THE SHORT TERM AS IT DEVELOPS A DEEPENING STORM SYSTEM OVER THE NRN PLAINS LATE TONIGHT AND BRINGS IT TOWARD THE WRN GREAT LAKES LATE WED INTO WED NIGHT. TONIGHT...ANY LEFTOVER DIURNAL SHSN OVER S CNTRL UPPER MI WILL DIMINISH EARLY THIS EVENING AS PARTLY CLOUDY SKIES AND LIGHT WINDS ALLOW TEMPS TO FALL INTO THE LOW SINGLE DIGITS OVER TYPICAL COLD SPOTS FAR EAST TO 15 TO 20F RANGE FOR DOWNSLOPING AREAS ALONG LAKE SUPERIOR FAR WEST AND AREAS CLOSE TO BAY OF GREEN BAY. TEMPS MAY CLIMB LATE AS CLOUDS INCREASE AHEAD OF THE APPROACHING LOW PRESSURE SYSTEM. WAA LIGHT SNOW WITH INCREASING 280K-290K ISENTROPIC LIFT IS EXPECTED TO REMAIN MAINLY WEST OF UPPER MI BUT MAY SLIDE INTO THE FAR WEST LATE. WEDNESDAY...MODELS GENERALLY IN AGREEMENT SHOWING SHORTWAVE OF INTEREST AND ASSOC DEEPENING SFC LOW OVER SE SOUTH DAKOTA AROUND 12Z THEN DIFFER ON HOW QUICKLY THEY LIFT THIS LOW ENE TOWARD THE UPPER GREAT LAKES. MOST OF 12Z MODELS GENERALLY TRENDING SLIGHTLY SLOWER AND FARTHER SE THAN 06Z RUNS WITH TRACK OF SFC LOW. MODELS INDICATE WARM AIR ADVECTION AND ISENTROPIC ASCENT ALONG AND AHEAD OF THE LOW AND INVERTED SFC TROUGH SHOULD SUPPORT EXPANDING SNOW SHIELD FM CNTRL MINNESOTA INTO NORTHWEST WI LATE TONIGHT THROUGH DAYBREAK ON WEDNESDAY. THIS SNOW SHIELD WILL THEN SPREAD INTO WEST AND CENTRAL UPPER MI DURING THE DAY ON WEDNESDAY. AS SFC TROUGH EDGES CLOSER TO UPR MICHIGAN WED AFTN ISENTROPIC ASCENT BECOMES MAXIMIZED ON 285-290K SFCS ACROSS UPR MICHIGAN FROM 15Z INTO WED EVENING. GFS REMAINS QUICKEST OF 12Z MODELS WHILE THE ECMWF IS THE SLOWEST. THE NAM AND REGIONAL GEM FALL SOMEWHERE BTWN THESE SOLNS. H7 MIXING RATIOS IN 2.5-3 G/KG RANGE SUGGESTS 12 HOUR SNOW AMOUNTS 4-6 INCHES OVER MAINLY THE WEST HALF COUNTIES. IT/S POSSIBLE ACTUAL SNOW AMOUNTS ON WED COULD BE HELD DOWN SOME AS SNOW ARRIVES DURING THE DAYTIME WHEN INSOLATION COULD LIMIT ACCUMS ESPECIALLY ON HIGHER TRAFFIC/TRAVELLED ROADS. CROSS SECTIONS SUGGEST POSSIBILITY OF HEAVIER BANDED SNOWFALL OVER WESTERN COUNTIES WITH NEG EPV ABOVE FAIRLY STRONG 7H FGEN FORCING SO THIS COULD ADD A FEW INCHES TO THE 4-6 INCH TOTALS RENDERED SOLELY FM ISENTROPIC ASCENT. WITH ALL ABOVE FACTORS TAKEN INTO CONSIDERATION...HAVE DECIDED TO UPGRADE WATCHES OVER THE WEST HALF COUNTIES TO WARNINGS FROM MQT-DICKINSON WESTWARD. GENERALLY STARTED WARNINGS ON WED FM 14Z SOUTH TO 16Z NORTH. ALSO MOVED THE AXIS OF HEAVIER PCPN/SNOWFALL SLIGHTLY FARTHER EASTWARD BASED ON 12Z MODEL TRENDS WITH SNOWFALL AMOUNTS ON WED RANGING FM 3 TO 5 INCHES OVER THE NW CWA TO 4-7 INCHES OVER THE FAR SW CWA ALONG THE WI BDR. WENT WITH ADVISORIES FOR MNM...DELTA AND ALGER COUNTIES WHERE 2-4 INCH AMOUNTS WILL BE MORE COMMON ON WED WITH MUCH OF THE SNOW FALLING IN THE AFTERNOON HRS. FARTHER EAST OVER SCHOOLCRAFT AND LUCE COUNTIES...LOW-LVL DRY AIRMASS INITIALLY IN PLACE FROM LINGERING SFC RDG AXIS WILL TAKE A BIT LONGER TO MOISTEN FM ISENTROPIC ASCENT SO ONLY EXPECT GENERALLY 1-2 INCHES OF SNOW THERE AND WILL HOLD OFF ON ANY HEADLINE THERE FOR NOW. IF TONIGHT/S MODEL RUNS CONTINUE TO TREND EASTWARD MAY NEED TO CONSIDER POSSIBILITY OF ADDING MNM AND POSSIBLY DELTA INTO WARNING. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 514 AM EDT WED APR 16 2014 THURSDAY...WITH THE SLOWER MODEL TREND...THE SHORTWAVE OVER NRN WI AND ASSOCIATED 700-500 QVECTOR CONV AND 290K-295 ISENTROPIC LIFT WILL CONTINUE TO SUPPORT MODERATE SNOW IN THE MORNING...WITH ADDITIONAL ACCUMULATIONS IN THE 1 TO 3 INCH RANGE...GREATEST OVER THE NW HALF. THE STRONGER DYNAMICS AND PCPN WILL QUICKLY LIFT TO THE NORTHEAST BY AFTERNOON WITH LITTLE ADDITIONAL SNOW. THERE MAY ALSO BE A MIX OF LIGHT RAIN OVER THE SOUTH AND EAST PORTIONS OF THE CWA. THURSDAY NIGHT...MOIST LOW LEVEL CYCLONIC FLOW BEHIND THE DEPARTING LOW WILL RESULT IN MOSTLY CLOUDY SKIES AND SHOULD KEEP MIN TEMPS IN THE LOW TO MID 20S. FRIDAY...IF CLOUDS DO CLEAR OUT IN SOME AREAS THU NIGHT...EXPECT BKN DIURNAL CU DEVELOPMENT FRI UNDER THE MID LEVEL TROF AND ASSOCIATED THERMAL TROF WITH 850/700 MB TEMPS AROUND -10C/-15C. ALTHOUGH THE STEEP LOW LEVEL LAPSE RATES COULD SUPPORT SOME FLURRIES...NO ACCUMULATION IS EXPECTED. FRI HIGHS WILL BE IN THE 30S NORTH WITH A COLD WIND OFF THE ICE TO THE 40S S. WITH CLOUDS CLEARING OUT FRI NIGHT...IT WILL BE A COLD NIGHT WITH HIGH PRES STILL OVER THE AREA. FAVORED THE LOWER SIDE OF GUIDANCE WITH SOME TEENS OVER THE W WHERE WINDS WILL BE LIGHTEST. COULD BE CONSIDERABLY COLDER ACROSS ALL OF THE INTERIOR IF SKIES CLEAR EARLY AND STAY THAT WAY FOR A GOOD PART OF THE NIGHT. SAT INTO SUN...A SHORTWAVE TROUGH OVER THE PAC NW THU WILL REACH NRN ONTARIO SAT NIGHT INTO SUN. THE GEM AND ECMWF REMAINED MORE PROGRESSIVE AND STRONGER WITH THE NRN PORTION OF THE SHRTWV...DRAGGING THE FRONTAL SYSTEM THROUGH UPPER MI FASTER THAN THE GFS. LOW LEVEL TEMPS WILL BE WARM ENOUGH FOR MAINLY RAIN. EXPECT THE GREATEST RAIN CHANCE SAT NIGHT WITH SOME CLEARING POSSIBLE SUN AS DRIER AIR MOVES IN FROM THE WEST. TEMPERATURES SHOULD CLIMB BACK INTO THE LOWER TO MID 40S BY SUN AFTERNOON. MON/TUE...THE MODELS SUGGEST THAT THE PATTERN WILL AMPLIFY AS A TROUGH DIGS INTO THE WEST COAST. AS A RESULT THE NRN LAKES WILL BE ON THE EDGE OF THE WARMER AIR AS A RIDGE BUILDS OVER THE PLAINS. TEMPS SHOULD CLIMB BACK TO NEAR NORMAL WITH HIGHS IN THE UPPER 40S AND LOWER 50S WITH MIN READINGS IN THE LOWER 30S. SOME LIGHT RAIN MAY BE POSSIBLE WITH ANY WEAK SHRTWVS EMBEDDED IN THE WNW FLOW THROUGH THE REGION. HOWEVER...ANY AMOUNTS WOULD BE VERY LIGHT. SO...ONLY SLIGHT CHANCE POPS SEEM ON TRACK. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 133 AM EDT WED APR 16 2014 LIGHT WINDS WILL PERSIST THROUGH THE NIGHT AS HIGH PRESSURE MOVES THROUGH THE REGION. THEN AN APPROACHING STORM SYSTEM WILL BRING INCREASING CLOUDS AND SNOW TO THE AREA. KIWD WILL SEE THE IMPACTS FIRST...WITH IFR VSBYS DEVELOPING THERE BY MIDDAY IN LIGHT TO MODERATE SNOW. THE SNOW WILL THEN SPREAD TO KCMX AND KSAW THROUGH THE REMAINDER OF THE DAY. CIGS TO LOWER DURING THE DAY WITH IFR CONDITIONS DEVELOPING AS THE SYSTEM CLOSES IN ON THE AREA AND PERSISTING THROUGH THE END OF THE FORECAST. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 531 PM EDT TUE APR 15 2014 WINDS LESS THAN 20 KTS THROUGH TONIGHT WITH SFC HIGH PRES RIDGE OVER THE AREA. APPROACHING LOW PRESSURE SYSTEM FM THE PLAINS WILL RESULT IN INCREASING EAST TO NORTHEAST WINDS ON WEDNESDAY. WENT WITH A GALE WARNING FOR FAR WRN LAKE SUPERIOR WEDNESDAY AFTN INTO THU MORNING AS WINDS ARE ENHANCED DUE TO CHANNELING AND TERRAIN EFFECTS. WINDS SHIFT TO THE NORTH-NORTHWEST TO 25 KTS BY THURSDAY AFTERNOON AS THE LOW WEAKENS WHILE MOVING OVER ERN LK SUPERIOR. EXPECT WINDS STAY BLO 20 KTS FOR THE REST OF THE FORECAST PERIOD. && .HYDROLOGY... ISSUED AT 531 PM EDT TUE APR 15 2014 RECENT COLDER WEATHER AND CONTINUATION OF COLDER WEATHER FOR THE NEXT FEW DAYS WILL RESULT IN SLOW RUNOFF OF MELTING SNOW. THUS... RIVER LEVELS SHOULD NOT SHOW ANY SIGNIFICANT FLUCTUATIONS. HOWEVER...ICE JAMS COULD BE AN ISSUE AS THEY HAVE BEEN IN SOME AREAS. HOWEVER...DIMINISHED RUNOFF SHOULD REDUCE THE POTENTIAL FOR ADDITIONAL ICE JAMS. WIDESPREAD PRECIPITATION IS IN THE FORECAST FOR WEDNESDAY THROUGH THURSDAY MORNING WITH THE POTENTIAL FOR 0.50 TO 1.25 INCHES OF LIQUID EQUIVALENT PRECIPITATION...GREATEST OVER THE W HALF OF UPPER MICHIGAN. THIS PRECIP ADDED TO EXISTING SNOWPACK WITH WATER EQUIVALENT OF 4-9 INCHES WILL RESULT IN ANOTHER PERIOD OF SNOWMELT RUNOFF/RIVER RISES AND POSSIBLE ICE JAMS ONCE WARMER TEMPERATURES ARRIVE NEXT WEEK. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... WINTER WEATHER ADVISORY FROM 2 PM THIS AFTERNOON TO NOON EDT THURSDAY FOR MIZ006-013. WINTER STORM WARNING FROM NOON TODAY TO 11 AM EDT THURSDAY FOR MIZ004-084. WINTER STORM WARNING FROM NOON TODAY TO NOON EDT THURSDAY FOR MIZ005. WINTER STORM WARNING FROM 11 AM EDT /10 AM CDT/ THIS MORNING TO 11 AM EDT /10 AM CDT/ THURSDAY FOR MIZ002-009>011. WINTER STORM WARNING FROM 2 PM THIS AFTERNOON TO NOON EDT THURSDAY FOR MIZ001-003. WINTER WEATHER ADVISORY FROM 9 AM THIS MORNING TO 10 AM CDT THURSDAY FOR MIZ012. LAKE SUPERIOR... GALE WARNING FROM 6 PM EDT /5 PM CDT/ THIS EVENING TO 6 AM EDT /5 AM CDT/ THURSDAY FOR LSZ162. LAKE MICHIGAN... NONE. && $$ SHORT TERM...VOSS LONG TERM...JLB AVIATION...RJT MARINE...VOSS HYDROLOGY...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
134 AM EDT WED APR 16 2014 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 531 PM EDT TUE APR 15 2014 BIGGEST FORECAST CONCERNS FOR SHORT TERM FOCUS ON WINTER STORM HEADLINES STARTING WEDNESDAY AND CONTINUING INTO THURSDAY. WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH FROM HUDSON BAY THROUGH THE CENTRAL GREAT LAKES INTO THE GULF COAST STATES. INSTABILITY ASSOC WITH THIS TROUGH HAS SUPPORTED SOME DIURNAL -SHSN ACROSS INLAND AREAS THIS AFTERNOON. THE SHORTWAVE MOVING IN OFF THE PAC NW WILL BE THE FEATURE OF INTEREST IN THE SHORT TERM AS IT DEVELOPS A DEEPENING STORM SYSTEM OVER THE NRN PLAINS LATE TONIGHT AND BRINGS IT TOWARD THE WRN GREAT LAKES LATE WED INTO WED NIGHT. TONIGHT...ANY LEFTOVER DIURNAL SHSN OVER S CNTRL UPPER MI WILL DIMINISH EARLY THIS EVENING AS PARTLY CLOUDY SKIES AND LIGHT WINDS ALLOW TEMPS TO FALL INTO THE LOW SINGLE DIGITS OVER TYPICAL COLD SPOTS FAR EAST TO 15 TO 20F RANGE FOR DOWNSLOPING AREAS ALONG LAKE SUPERIOR FAR WEST AND AREAS CLOSE TO BAY OF GREEN BAY. TEMPS MAY CLIMB LATE AS CLOUDS INCREASE AHEAD OF THE APPROACHING LOW PRESSURE SYSTEM. WAA LIGHT SNOW WITH INCREASING 280K-290K ISENTROPIC LIFT IS EXPECTED TO REMAIN MAINLY WEST OF UPPER MI BUT MAY SLIDE INTO THE FAR WEST LATE. WEDNESDAY...MODELS GENERALLY IN AGREEMENT SHOWING SHORTWAVE OF INTEREST AND ASSOC DEEPENING SFC LOW OVER SE SOUTH DAKOTA AROUND 12Z THEN DIFFER ON HOW QUICKLY THEY LIFT THIS LOW ENE TOWARD THE UPPER GREAT LAKES. MOST OF 12Z MODELS GENERALLY TRENDING SLIGHTLY SLOWER AND FARTHER SE THAN 06Z RUNS WITH TRACK OF SFC LOW. MODELS INDICATE WARM AIR ADVECTION AND ISENTROPIC ASCENT ALONG AND AHEAD OF THE LOW AND INVERTED SFC TROUGH SHOULD SUPPORT EXPANDING SNOW SHIELD FM CNTRL MINNESOTA INTO NORTHWEST WI LATE TONIGHT THROUGH DAYBREAK ON WEDNESDAY. THIS SNOW SHIELD WILL THEN SPREAD INTO WEST AND CENTRAL UPPER MI DURING THE DAY ON WEDNESDAY. AS SFC TROUGH EDGES CLOSER TO UPR MICHIGAN WED AFTN ISENTROPIC ASCENT BECOMES MAXIMIZED ON 285-290K SFCS ACROSS UPR MICHIGAN FROM 15Z INTO WED EVENING. GFS REMAINS QUICKEST OF 12Z MODELS WHILE THE ECMWF IS THE SLOWEST. THE NAM AND REGIONAL GEM FALL SOMEWHERE BTWN THESE SOLNS. H7 MIXING RATIOS IN 2.5-3 G/KG RANGE SUGGESTS 12 HOUR SNOW AMOUNTS 4-6 INCHES OVER MAINLY THE WEST HALF COUNTIES. IT/S POSSIBLE ACTUAL SNOW AMOUNTS ON WED COULD BE HELD DOWN SOME AS SNOW ARRIVES DURING THE DAYTIME WHEN INSOLATION COULD LIMIT ACCUMS ESPECIALLY ON HIGHER TRAFFIC/TRAVELLED ROADS. CROSS SECTIONS SUGGEST POSSIBILITY OF HEAVIER BANDED SNOWFALL OVER WESTERN COUNTIES WITH NEG EPV ABOVE FAIRLY STRONG 7H FGEN FORCING SO THIS COULD ADD A FEW INCHES TO THE 4-6 INCH TOTALS RENDERED SOLELY FM ISENTROPIC ASCENT. WITH ALL ABOVE FACTORS TAKEN INTO CONSIDERATION...HAVE DECIDED TO UPGRADE WATCHES OVER THE WEST HALF COUNTIES TO WARNINGS FROM MQT-DICKINSON WESTWARD. GENERALLY STARTED WARNINGS ON WED FM 14Z SOUTH TO 16Z NORTH. ALSO MOVED THE AXIS OF HEAVIER PCPN/SNOWFALL SLIGHTLY FARTHER EASTWARD BASED ON 12Z MODEL TRENDS WITH SNOWFALL AMOUNTS ON WED RANGING FM 3 TO 5 INCHES OVER THE NW CWA TO 4-7 INCHES OVER THE FAR SW CWA ALONG THE WI BDR. WENT WITH ADVISORIES FOR MNM...DELTA AND ALGER COUNTIES WHERE 2-4 INCH AMOUNTS WILL BE MORE COMMON ON WED WITH MUCH OF THE SNOW FALLING IN THE AFTERNOON HRS. FARTHER EAST OVER SCHOOLCRAFT AND LUCE COUNTIES...LOW-LVL DRY AIRMASS INITIALLY IN PLACE FROM LINGERING SFC RDG AXIS WILL TAKE A BIT LONGER TO MOISTEN FM ISENTROPIC ASCENT SO ONLY EXPECT GENERALLY 1-2 INCHES OF SNOW THERE AND WILL HOLD OFF ON ANY HEADLINE THERE FOR NOW. IF TONIGHT/S MODEL RUNS CONTINUE TO TREND EASTWARD MAY NEED TO CONSIDER POSSIBILITY OF ADDING MNM AND POSSIBLY DELTA INTO WARNING. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 531 PM EDT TUE APR 15 2014 LONG TERM PORTION OF THE FCST WILL BEGIN COLD/WINTRY AS SHORTWAVE TAKES ADVANTAGE OF LINGERING TIGHT THERMAL GRADIENT OVER THE AREA BTWN DEPARTING UNUSUALLY COLD AIR MASS FOR MID APR AND WARMTH SPREADING OUT ACROSS THE CNTRL/SRN PLAINS. TEMPS WILL THEN SLOWLY MODERATE AS DEEP TROF AND ASSOCIATED LATE SEASON ARCTIC AIR LIFT TO GREENLAND...AND PACIFIC AIR MAKES INCREASING INROADS ACROSS THE CONUS AND SRN CANADA. HEADING DOWN THE ROAD...IT LOOKS LIKE TEMPS NEXT WEEK WILL GENERALLY FLUCTUATE AROUND NORMAL...BUT NOT SIGNIFICANTLY ABOVE OR BLO NORMAL DURING THE TEMP SWINGS. THERE ARE SOME INDICATIONS FROM GEM ENSEMBLES AND GFS RUNS THAT THE PATTERN MAY BE FAIRLY ACTIVE OVER THE NEXT COUPLE OF WEEKS WHICH WILL MEAN RAINFALL FOR MOST IF NOT ALL PCPN EVENTS. HOPEFULLY...SIGNIFICANT RAINFALL WILL BE AVOIDED AS THE SNOWMELT SEASON RESUMES. BEGINNING WED NIGHT...A HVY/WET SNOW EVENT WILL BE UNDERWAY AS SHORTWAVE APPROACHES FROM THE UPPER MISSISSIPPI VALLEY. WITH 12Z MODEL RUNS...MODELS THAT HAD MAX QPF AXIS ON THE NW SIDE OF THE MODEL SPREAD HAVE SHIFTED SLIGHTLY S AND E. RESULT IS IMPROVING MODEL AGREEMENT NOW ON WHERE AXIS OF HEAVIEST PCPN WILL SET UP. IT APPEARS MAX QPF AXIS SHOULD RUN ROUGHLY FROM JUST N OF THE TWIN CITIES TO THE HURON MTNS. THE NAM IS DISPLACED A LITTLE TO THE NW OF THIS AXIS WHILE THE GEM REGIONAL/HEMISPHERIC ARE DISPLACED A LITTLE TO THE SE. ALTHOUGH SFC LOW ASSOCIATED WITH SHORTWAVE WILL BE WEAKENING AS IT TRACKS FROM THE NRN/CNTRL PLAINS TO THE UPPER LAKES...BEST COMBINATION OF FORCING/MOISTURE WILL COME TOGETHER FROM ERN MN E AND NE NTO UPPER MI BEFORE SYSTEM BEGINS TO FALL APART. AT THE UPPER LEVELS...RIGHT ENTRANCE OF UPPER JET STREAK RUNNING FROM NRN LAKE SUPERIOR/NRN ONTARIO EASTWARD WILL PROVIDE HEALTHY UPPER DIVERGENCE. THERE ARE EVEN SOME HINTS OF BRIEF UPPER JET COUPLING WITH LEFT EXIT OF JET SHIFTING ACROSS THE UPPER MIDWEST THAT IS SUPPORTING THE SHORTWAVE. AT THE LOWER LEVELS...STRONG ISENTROPIC ASCENT IS NOTED WITH MIXING RATIOS OF 3 TO 4G/KG AVBL AROUND 700-750MB. IN ADDITION...THERE IS STRONG FRONTOGENESIS WITH NEGATIVE EPV/CONVECTIVE INSTABILITY NOTED OVERTOP THE FGEN. FINALLY...STEEP MIDLEVEL LAPSE RATES ARE NOTED ADVECTING INTO THE SRN SIDE OF THE PCPN AREA. ALL THIS POINTS TO THE LIKELIHOOD FOR HEAVIER BANDING OF SNOW WITHIN THE OVERALL MDT/HVY PCPN AREA OR EVEN CONVECTIVE SNOW AT TIMES...CERTAINLY NOT ATYPICAL FOR SPRINGTIME HVY SNOW EVENTS. ULTIMATE PLACEMENT OF HEAVIEST SNOW WILL HINGE ON WHERE THESE HEAVIER SNOWBANDS OR CONVECTIVE ELEMENTS SET UP. AS IT STANDS NOW...LOCATIONS W OF KIMT/KMQT LINE SHOULD HAVE NO PROBLEM REACHING WARNING CRITERIA WITH STORM TOTAL AMOUNTS AROUND 1 FOOT...PROBABLY IN MANY LOCATIONS. ADVY ISSUED FOR NEXT TIER OF COUNTIES E MAY IN FACT NEED TO BE UPGRADED TO WARNINGS GIVEN MODEL TRENDS. FINALLY... EVEN THE FAR E COUNTIES OF SCHOOLCRAFT AND LUCE MAY NEED TO BE ADDED TO AN ADVY IF THE E TREND HOLDS UP IN NEXT SET OF MODEL RUNS. PCPN WINDS DOWN QUICKLY THU AND WILL LIKELY END. SFC HIGH PRES THEN BUILDS INTO THE UPPER LAKES THU NIGHT THRU FRI NIGHT TO PROVIDE A PERIOD OF QUIET WEATHER. NAM IN PARTICULAR SUGGESTS LOW CLOUDS MAY LINGER THU NIGHT...AND THAT MAY BE THE CASE WITH SHALLOW COLD AIR MASS OVER EXPANDING OPEN WATER ON LAKE SUPERIOR. IF CLOUDS DO CLEAR OUT IN SOME AREAS THU NIGHT...EXPECT BKN DIURNAL CU DEVELOPMENT FRI UNDER MID LEVEL TROF AND ASSOCIATED THERMAL TROF. NOT OUT OF THE QUESTION THAT A FEW FLURRIES COULD EVEN DEVELOP. FRI HIGHS WILL BE IN THE 30S N WITH A CHILLY WIND OFF THE ICE TO THE 40S S. WITH CLOUDS CLEARING OUT FRI NIGHT...IT WILL BE A COLD NIGHT WITH HIGH PRES STILL OVER THE AREA. FAVORED THE LOWER SIDE OF GUIDANCE WITH SOME TEENS OVER THE W WHERE WINDS WILL BE LIGHTEST. COULD BE CONSIDERABLY COLDER ACROSS ALL OF THE INTERIOR IF SKIES CLEAR EARLY AND STAY THAT WAY FOR A GOOD PART OF THE NIGHT. MODELS THEN DIVERGE WITH PROGRESSION OF NEXT SHORTWAVE FEATURE MOVING OFF THE PACIFIC IN LOWER AMPLITUDE FLOW...THOUGH AGREEMENT IS IMPROVING WITH TODAYS 12Z MODEL RUNS. GEM IS STRONGER WITH WAVE AND IS HEAVIER WITH THE QPF THAN THE GFS/ECWMF. HOWEVER...BOTH THE GFS AND ECMWF ARE TRENDING TOWARD A WETTER SYSTEM NOW. SOME -RA POSSIBLY MIXED WITH A LITTLE SNOW OVER HIGHER TERRAIN WILL PROBABLY REACH THE W SAT AFTN...THEN SPREAD E SAT NIGHT/SUN. WITH WETTER TRENDS NOTED...WILL TRENDING POPS UP TO CHC. MON/TUE...ECMWF HAS BEEN CONSISTENT SHOWING TROF DEVELOPMENT INTO THE W COAST WITH DOWNSTREAM RIDGE BUILDING INTO THE ROCKIES/WRN PLAINS WHILE TROF SETTLES INTO THE ERN CONUS. THE GFS IS CONSIDERABLY MORE PRONOUNCED WITH EASTWARD EXTENT OF RIDGE/HIGHER HEIGHTS INTO THE GREAT LAKES...BUT THE 12Z GFS IS NOW SHOWING SIGNS OF HEADING IN THE DIRECTION OF THE ECMWF. WILL LEAN TOWARD THE MORE CONSISTENT ECMWF WHICH TYPICALLY VERIFIES BETTER. RESULT IS A COOLER THAN GFS SCENARIO...BUT STILL CLOSE TO NORMAL FOR TEMPS. IF ANY MINOR WAVES TRACK SE ACROSS THE AREA INTO THE ERN TROF...THERE MAY BE SOME SCT LIGHT -SHRA AT TIMES. AT THIS POINT...NOTHING SUGGESTS THE NEED FOR AN EXPLICIT MENTION OF PCPN MON OR TUE. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 133 AM EDT WED APR 16 2014 LIGHT WINDS WILL PERSIST THROUGH THE NIGHT AS HIGH PRESSURE MOVES THROUGH THE REGION. THEN AN APPROACHING STORM SYSTEM WILL BRING INCREASING CLOUDS AND SNOW TO THE AREA. KIWD WILL SEE THE IMPACTS FIRST...WITH IFR VSBYS DEVELOPING THERE BY MIDDAY IN LIGHT TO MODERATE SNOW. THE SNOW WILL THEN SPREAD TO KCMX AND KSAW THROUGH THE REMAINDER OF THE DAY. CIGS TO LOWER DURING THE DAY WITH IFR CONDITIONS DEVELOPING AS THE SYSTEM CLOSES IN ON THE AREA AND PERSISTING THROUGH THE END OF THE FORECAST. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 531 PM EDT TUE APR 15 2014 WINDS LESS THAN 20 KTS THROUGH TONIGHT WITH SFC HIGH PRES RIDGE OVER THE AREA. APPROACHING LOW PRESSURE SYSTEM FM THE PLAINS WILL RESULT IN INCREASING EAST TO NORTHEAST WINDS ON WEDNESDAY. WENT WITH A GALE WARNING FOR FAR WRN LAKE SUPERIOR WEDNESDAY AFTN INTO THU MORNING AS WINDS ARE ENHANCED DUE TO CHANNELING AND TERRAIN EFFECTS. WINDS SHIFT TO THE NORTH-NORTHWEST TO 25 KTS BY THURSDAY AFTERNOON AS THE LOW WEAKENS WHILE MOVING OVER ERN LK SUPERIOR. EXPECT WINDS STAY BLO 20 KTS FOR THE REST OF THE FORECAST PERIOD. && .HYDROLOGY... ISSUED AT 531 PM EDT TUE APR 15 2014 RECENT COLDER WEATHER AND CONTINUATION OF COLDER WEATHER FOR THE NEXT FEW DAYS WILL RESULT IN SLOW RUNOFF OF MELTING SNOW. THUS... RIVER LEVELS SHOULD NOT SHOW ANY SIGNIFICANT FLUCTUATIONS. HOWEVER...ICE JAMS COULD BE AN ISSUE AS THEY HAVE BEEN IN SOME AREAS. HOWEVER...DIMINISHED RUNOFF SHOULD REDUCE THE POTENTIAL FOR ADDITIONAL ICE JAMS. WIDESPREAD PRECIPITATION IS IN THE FORECAST FOR WEDNESDAY THROUGH THURSDAY MORNING WITH THE POTENTIAL FOR 0.50 TO 1.25 INCHES OF LIQUID EQUIVALENT PRECIPITATION...GREATEST OVER THE W HALF OF UPPER MICHIGAN. THIS PRECIP ADDED TO EXISTING SNOWPACK WITH WATER EQUIVALENT OF 4-9 INCHES WILL RESULT IN ANOTHER PERIOD OF SNOWMELT RUNOFF/RIVER RISES AND POSSIBLE ICE JAMS ONCE WARMER TEMPERATURES ARRIVE NEXT WEEK. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... WINTER WEATHER ADVISORY FROM NOON TODAY TO NOON EDT THURSDAY FOR MIZ006-013. WINTER STORM WARNING FROM NOON TODAY TO 11 AM EDT THURSDAY FOR MIZ004-084. WINTER STORM WARNING FROM NOON TODAY TO NOON EDT THURSDAY FOR MIZ005. WINTER STORM WARNING FROM 11 AM EDT /10 AM CDT/ THIS MORNING TO 11 AM EDT /10 AM CDT/ THURSDAY FOR MIZ002-009>011. WINTER STORM WARNING FROM 2 PM THIS AFTERNOON TO NOON EDT THURSDAY FOR MIZ001-003. WINTER WEATHER ADVISORY FROM 9 AM THIS MORNING TO 10 AM CDT THURSDAY FOR MIZ012. LAKE SUPERIOR... GALE WARNING FROM 2 PM EDT /1 PM CDT/ THIS AFTERNOON TO 11 AM EDT /10 AM CDT/ THURSDAY FOR LSZ162. LAKE MICHIGAN... NONE. && $$ SHORT TERM...VOSS LONG TERM...ROLFSON AVIATION...RJT MARINE...VOSS HYDROLOGY...ROLFSON
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
331 AM CDT WED APR 16 2014 .SHORT TERM...(TODAY THROUGH THURSDAY) ISSUED AT 331 AM CDT WED APR 16 2014 SNOW CHANCES TODAY WILL BE THE PRIMARY FORECAST HEADACHE FOR THE PERIOD. SNOW HAS STARTED TO DEVELOP ALONG A MID LEVEL FRONTOGENESIS BAND FROM NORTH CENTRAL ND DOWN TOWARDS FARGO AND FERGUS FALLS. THINK THE RAP SEEMS TO HAVE A DECENT HANDLE ON THE BAND...AND THINK THIS WILL STICK AROUND AND DROP AN INCH OR TWO BEFORE DIMINISHING AS THE SFC LOW WRAPS UP AND FRONTOGENESIS STRENGTHENS FURTHER SOUTH. FOR LATER TODAY... THE SHORTWAVE CURRENTLY MOVING INTO THE WESTERN PLAINS WILL QUICKLY PROGRESS EASTWARD INTO SOUTHERN MN. SFC LOW PRESSURE WILL MOVE FROM SOUTHERN SD TO THE IA/MN BORDER...WITH OUR SOUTHERN COUNTIES ON THE NORTHERN EDGE OF THE DEFORMATION BAND. THE GEM KEEPS MOST OF THE SNOW FURTHER TO THE SOUTH...BUT THE OTHER DETERMINISTIC MODELS STILL BRING SOME 3 TO 6 INCH AMOUNTS TO OUR SOUTHEASTERN COUNTIES. WILL CONTINUE TO KEEP THE STATUS QUO AND KEEP HIGH POPS AND THE ADVISORY GOING FOR OUR SOUTHEASTERN COUNTIES. MAIN CHANGE FOR TODAY WAS TO ADD IN A BRIEF PATCHY BLOWING SNOW MENTION FOR WHEN PRECIP IS FALLING IN OUR SOUTHEAST...AS NORTHEASTERLY WINDS WILL BE QUITE STRONG TODAY AT TIMES. THE SNOW WILL RAPIDLY TAPER OFF THIS EVENING AS THE MAIN SHORTWAVE TAKES OFF INTO WI AND HIGH PRESSURE BUILDS DOWN INTO THE NORTHERN PLAINS. SKIES WILL BEGIN TO CLEAR OUT ALTHOUGH THE WINDS WILL STAY UP AND KEEP US FROM COMPLETELY BOTTOMING OUT...WITH LOWS STAYING IN THE TEENS TO LOW 20S. SFC HIGH PRESSURE WILL CONTINUE INTO THURSDAY WITH DECREASING WINDS AND MOSTLY SUNNY SKIES. THE AIR MASS WILL STILL BE PRETTY COLD HOWEVER...SO KEPT TEMPS IN THE 30S TO AROUND 40 DEGREES. .LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY) ISSUED AT 331 AM CDT WED APR 16 2014 THURSDAY NIGHT THROUGH FRIDAY NIGHT...NORTHWESTERLY FLOW ALOFT BEGINS TO SHIFT AS A RIDGE BRIEFLY BUILDS IN AHEAD OF THE NEXT SHORTWAVE MOVING INTO SASK. A TROUGH OF LOW PRESSURE DEVELOPING OVER THE NORTHERN ROCKIES WILL BEGIN TO SHIFT WINDS BACK TO THE SOUTHEAST. MODELS HAVE A WEAK REINFORCING SHORTWAVE MOVING BY THURSDAY NIGHT BUT THINK THAT ANYTHING IT PRODUCES WILL STAY TO OUR SOUTH AND WEST. FRIDAY WILL BE A BIT WARMER THAN EARLIER IN THE WEEK BUT STILL BELOW AVERAGE WITH HIGHS IN THE 40S. MODELS DIVERGE ON BRINGING THE NEXT ROUND OF PRECIP THROUGH IN THE WARM AIR ADVECTION AHEAD OF THE NEXT SHORTWAVE. THE ECMWF AND PARTICULARLY THE GEM HAVE PRECIP MOVING QUICKLY EASTWARD FRIDAY NIGHT...WHILE THE GFS AND NAM ARE MUCH SLOWER. WILL GO WITH A BIT OF A BLEND...BUT GIVEN THE WAY SATURATION HAS TAKEN ITS TIME...LEANED A BIT TOWARDS THE SLOWER SOLUTION. JUST KEPT SOME SLIGHT POPS IN THE EAST WITH NEAR 40 PERCENT IN THE WEST FOR NOW. SATURDAY THROUGH TUESDAY NIGHT...00 UTC GFS/ECMWF ARE IN FAIR AGREEMENT. ON SATURDAY...A NEGATIVELY TILTED SHORT-WAVE WILL ROTATE THROUGH THE NORTHERN PLAINS BRINGING WARM AIR ADVECTION-INDUCED PRECIP ACROSS THE FORECAST AREA. FLOW ALOFT THEREAFTER THROUGH TUESDAY BECOMES MORE ZONAL WITH A SLIGHT PROPENSITY FOR SHORT-WAVE RIDGING. SUNDAY/MONDAY LOOK DRY...BUT PRECIP CHANCES WILL INCREASE AGAIN LATE TUESDAY INTO WEDNESDAY AS A DEEP TROUGH TAKES SHAPE ACROSS THE GREAT BASIN TURNING THE FLOW ACROSS THE NATION/S MID-SECTION TO THE SOUTHWEST. WITH THE EXCEPTION OF A RAIN/SNOW MIX AT NIGHT... MAJORITY OF PRECIP SHOULD FALL AS RAIN THROUGH THE PERIOD. AFTER ONE MORE RELATIVELY COOLER DAY ON SATURDAY (HIGHS FROM THE MID 40S TO NEAR 50 DEGREES)...MID-LEVEL THERMAL RIDGE PUSHES EAST ALLOWING TEMPERATURES TO CLIMB INTO THE 50S AND 60S SUNDAY INTO EARLY NEXT WEEK. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 1151 PM CDT TUE APR 15 2014 EAST WINDS WILL INCREASE AS SFC LOW MOVES INTO ERN SD BY 12Z WED AND EAST TO NORTHEAST WINDS WILL 15 TO 30 KTS DURING THE DAY WEDNESDAY. IT APPEARS BEST SHOT OF ANY MVFR CIGS/VSBYS REMAIN IN FARGO LATE TONIGHT THROUGH DAYBREAK TIL ABOUT LATE MORNING. OTHERWISE KEPT VFR CIGS BUT COULD BE ISOLD MVFR CIGS AT TIMES DVL BASIN INTO GFK-BJI AREAS. UNCERTAIN ON TIMING AND LOW CONFIDENCE LEADS TO ME TO KEEP IT MOSTLY LOW END VFR THRU WED AFTN BEFORE CLEARING MOVES SOUTH. && .HYDROLOGY... ISSUED AT 331 AM CDT WED APR 16 2014 THE COLD NIGHTS...COOL DAYTIME HIGHS AND DIMINISHING SNOW PACK ARE PUTTING A DAMPER ON ANY ADDITIONAL RUNOFF. ISSUED LAST FORECASTS FOR SABIN...DILWORTH AND GRAFTON. THE REMAINING POINTS WITH HYDROLOGIC STATEMENTS OR FLOOD STATEMENTS ARE AT OR NORTH OF GRAND FORKS. ONLY SITES STILL RISING ARE DRAYTON AND PEMBINA ON THE RED RIVER. THE SNAKE RIVER AT ALVARADO HAS POKED ABOVE MODERATE FLOOD STAGE BY A TENTH OF A FOOT OVER THE PAST 4 TO 5 HOURS...BUT HAS BEGUN TO STABILIZE AND FULLY EXPECT IT TO BEGIN FALLING SOON GIVEN UPSTREAM FLOW NEAR WARREN. STILL ANTICIPATE THE COOLER WEATHER LASTING INTO THURSDAY WITH SOME MODERATION BY LATE WEEK INTO THE WEEKEND. TODAY/S STORM SYSTEM WILL MAINLY AFFECT PORTIONS OF WEST CENTRAL MINNESOTA WITH LITTLE OR NO PRECIPITATION OVER THE NORTHERN RED RIVER VALLEY. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...WINTER WEATHER ADVISORY UNTIL 6 PM CDT THIS EVENING FOR MNZ030>032-040. && $$ SHORT TERM...JR LONG TERM...ROGERS AVIATION...RIDDLE HYDROLOGY...ROGERS
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
1238 AM EDT WED APR 16 2014 .SYNOPSIS... HIGH PRESSURE WILL BUILD OVER THE FORECAST AREA TONIGHT. THIS SYSTEM WILL REMAIN OVER THE REGION THROUGH THURSDAY. A COLD FRONT WILL MOVE ACROSS THE AREA FRIDAY EVENING. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... THE DIURNAL SHSN HAVE MOSTLY DISSIPATED LEAVING MOSTLY JUST LAKE EFFECT SHSN. STILL NOT GETTING AN HRRR MODEL RUNS BUT LATEST RUC STILL HAS LAST OF MEASURABLE SHSN ENDING BY 05Z. BASED ON THE RUC AND LATEST RADAR AND SAT PIX...LOOKS LIKE ONGOING FORECAST REMAINS IN LINE SO NO CHANGES OF SIGNIFICANCE FOR LATE EVENING UPDATE. FROM HERE ON OUT ANY ADDITIONAL ACCUMULATION SHOULD JUST A HALF AN INCH OR LESS HERE AND THERE WHERE SNOW SHOWERS PERSIST. && .SHORT TERM /6 AM THIS MORNING THROUGH FRIDAY NIGHT/... HIGH PRESSURE WILL REMAIN IN CONTROL OF THE WEATHER PATTERN FOR THE MID TO LATER PART OF THE WEEK. A RETURN FLOW ON THE BACK SIDE OF THE HIGH WILL ALLOW TEMPERATURES TO START A REBOUND ON WEDNESDAY AND CLIMB BACK TO NEAR NORMALS ON THURSDAY. THE GFS AND NAM SHOW AN APPROACHING COLD FRONT ON FRIDAY. THE NAM IS A LITTLE QUICKER AND A LITTLE MORE AGGRESSIVE WITH THE MOISTURE WITH THE SYSTEM THAN THE GFS. I WILL WORK SCATTERED PRECIPITATION ACROSS THE AREA WITH MORNING SHOWERS IN NW OHIO AND THEN AFTERNOON SHOWERS IN NE OH AND NW PA. 850MB TEMPERATURES DROP BELOW -2C FRIDAY NIGHT. WE MAY HAVE TO WATCH PRECIPITATION TYPE AS WELL. RIGHT NOW I WILL NOT INCLUDE ANY MIXED PRECIPITATION FRIDAY NIGHT. && .LONG TERM /SATURDAY THROUGH TUESDAY/... THE EXTENDED FORECAST BEGINS WITH A SHARP LONGWAVE RIDGE MOVING INTO THE GREAT LAKES REGION. ALL OF SATURDAY AND MOST OF SUNDAY WILL BE DRY. A FAST MOVING SHORTWAVE TROUGH ON THE HEELS OF SATURDAY`S RIDGE WILL ELEVATE POPS ACROSS THE TOLEDO METRO AREA AS EARLY AS SUNDAY AFTERNOON...BUT CHANCE FOR MEASURABLE PRECIP WILL BE LOW AS THE TROUGH FLATTENS OUT. MONDAY AND THE FIRST PART OF TUESDAY LOOK LIKE THE BETTER DAY FOR RAIN AS A SLOW MOVING DISTURBANCE DEVELOPS OVER THE DEEP SOUTH AND DRAWS UP GULF MOISTURE TOWARDS THE OHIO VALLEY. THE GOOD NEWS IS THE LAST OF THE COLD WEATHER APPEARS TO BE BEHIND US WITH HIGH TEMPERATURES FORECAST TO BE NEARLY NORMAL. && .AVIATION /00Z WEDNESDAY THROUGH SUNDAY/... HIGH PRESSURE OVER THE AREA WILL MOVE TO NEW ENGLAND THIS AFTERNOON. AIRMASS IS COOL ENOUGH TO GET LAKE EFFECT CLOUDS IN NORTHWEST FLOW BUT MOST OF THIS WILL BE GONE BY MORNING AS FLOW WEAKENS AND AIRMASS DRIER FURTHER. WILL HOLD ONTO MVFR CIGS AT KYNG FOR A FEW MORE HOURS BUT THEN LIFT TO VFR. .OUTLOOK...NON VFR MAY DEVELOP FRIDAY AND PERSIST INTO SATURDAY. && .MARINE... THE SMALL CRAFT ADVISORY IS STILL ON TRACK TO EXPIRE LATER TONIGHT AS THE WIND ACROSS THE LAKE DIMINISHES IN RESPONSE TO A HIGH PRESSURE CENTER THAT WILL MOVE ACROSS NORTHERN OHIO LATER TONIGHT. IN THE WAKE OF THE HIGH THE WIND WILL SHIFT FROM THE SOUTH...THEN GENERALLY THE SOUTHWEST AS THE NEXT SYSTEM EVOLVES OVER THE UPPER MIDWEST FOR PASSAGE OVER LAKE ERIE EARLY SATURDAY. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 3 AM EDT EARLY THIS MORNING FOR LEZ142>149. && $$ SYNOPSIS...GARNET NEAR TERM...GARNET SHORT TERM...GARNET LONG TERM...MAYERS AVIATION...TK MARINE...MAYERS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
411 AM CDT WED APR 16 2014 .SHORT TERM...(TODAY THROUGH TONIGHT) ISSUED AT 411 AM CDT WED APR 16 2014 MAIN CONCERN DEALING WITH STRONG LOW PRESSURE AND ITS IMPACT ON THE AREA...INCLUDING ACCUMULATING SNOW ACROSS NORTHERN WI AND GUSTY WINDS ELSEWHERE. SURFACE MAP EARLY THIS MORNING HAS AN AREA OF DEEPENING LOW PRESSURE OVER SOUTHERN SD WITH A WARM FRONT EXTENDING EASTWARD THROUGH CENTRAL IA. BROAD SCALE ISENTROPIC LIFT AND STRENGTHENING MID-LEVEL FRONTOGENESIS ACROSS CENTRAL MN INTO NORTHWEST WI STARTING TO FOCUS SOME -SN ACROSS THAT AREA. ELSEWHERE ACROSS THE AREA...SKIES WERE CLOUDY WITH TEMPERATURES RANGING FROM THE UPPER 20S TO LOWER 30S. MODELS COMING INTO BETTER AGREEMENT NOW WITH HANDLING OF PRECIPITATION ACROSS THE AREA TODAY THROUGH TONIGHT. LOOKING LIKE MODELS ARE TRENDING A FARTHER NORTH PUSH WITH PRECIPITATION ACROSS NORTHERN WI...IN THE FORM OF SNOW THIS MORNING...AND RAIN MIXING WITH SNOW BY THIS AFTERNOON. HAVE CONFINED HIGHER POPS A BIT FARTHER NORTH FOR TODAY...BUT A FEW MODELS INCLUDING THE RAP AND LATEST SREF SHOWING THE POSSIBILITY OF PRECIPITATION TOTALLY PUSHING NORTH OUT OF OUR AREA THIS AFTERNOON. 16.00Z DETERMINISTIC NAM/GFS/EC ALL SHOWING PRECIPITATION HANGING MAINLY ALONG AND NORTH OF THE I-94 CORRIDOR WITH ACCUMULATING SNOW THROUGH THIS MORNING MAINLY NORTH OF HIGHWAY 29 IN NORTHERN CLARK COUNTY. CURRENT THINKING WITH RADAR TREND AND THE 00Z MODELS IN MIND IS FOR SNOW THIS MORNING ACROSS CLARK/TAYLOR WITH 1-3 INCHES THROUGH LATE MORNING MAINLY NORTH OF HIGHWAY 29. WITH THIS IN MIND...WILL HANG ONTO THE WINTER WEATHER ADVISORY FOR NOW ACROSS CLARK AND TAYLOR...BUT STARTING TO HAVE MY DOUBTS WHETHER CARRYING IT PAST 18Z GIVEN WHAT THE RAP/SREF MODELS ARE SAYING. THIS IS OBVIOUSLY A QUICKLY CHANGING SITUATION AND WILL HAVE TO BE MONITORED CLOSELY BY THE DAY SHIFT TODAY. OTHER CONCERN FOR TODAY WILL BE INCREASING/GUSTY SOUTH WINDS MAINLY ALONG AND SOUTH OF THE I-90 CORRIDOR TODAY AHEAD OF THE DEEP LOW PRESSURE SYSTEM MOVING EAST ALONG THE IA/MN BORDER THIS AFTERNOON. WILL SEE SUSTAINED WINDS OF 20-30 MPH WITH SOME GUST AROUND 40 MPH. RIGHT NOW...WINDS LOOK BORDERLINE FOR A WIND ADVISORY...BUT WILL LET THE DAYSHIFT MONITOR THIS AS WELL. OTHERWISE...TEMPERATURES ACROSS THE AREA WILL VARY FROM AROUND 40 ACROSS NORTH CENTRAL WI...TO THE 50S ALONG/SOUTH OF I-90. FOR TONIGHT...THE LOW PRESSURE AREA WILL LIFT NORTHEAST INTO NORTHERN WI WITH DEFORMATION RAIN/SNOW...CHANGING TO ALL SNOW LOOKING LIKELY ACROSS EASTERN MN INTO NORTHERN WI. LOOKS LIKE THE SOUTHERN PERIPHERY OF OF THE DEFORMATION SNOW CLIPS CLARK AND TAYLOR WITH ACCUMULATING SNOW AGAIN TONIGHT...WITH AMOUNTS OF 1-2 INCHES. MEANWHILE...THERE ARE A FEW WRF MODELS SHOWING A BAND OF SHOWERS FORMING ALONG THE COLD FRONT OF THE LOW SWINGING ACROSS SOUTHERN PARTS OF THE AREA DURING THIS EVENING. PUSHED POPS INTO LIKELY CATEGORY BASED ON THIS SIGNAL. APPEARS PRECIPITATION MIXES AND CHANGES TO ALL SNOW THROUGH THE NIGHT ACROSS THE REST OF THE AREA WITH THE BULK OF THE PRECIPITATION LIFTING NORTHEAST OF I-94 BY MORNING. THEREFORE...LITTLE IF ANY SNOW ACCUMULATION EXPECTED SOUTHWEST OF I-94 THROUGH THE NIGHT. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 411 AM CDT WED APR 16 2014 THERE MAY BE SOME LINGERING LIGHT SNOW WITH MINIMAL ACCUMULATION THURSDAY MORNING NORTHEATS OF I-94. REST OF TEH DAY WILL BE MOSTLY CLOUDY...AND COOL WITH HIGHS ONLY MAKING IT INTO THE 40 TO 50 DEGREE RANGE. A COLD NIGHT THEN SETS UP THURSDAY NIGHT AS HIGH PRESSURE NOSES INTO THE AREA WITH LOWS DROPPING OFF INTO THE 20S. A MID-LEVEL SHORTWAVE TROUGH/PV-ADVECTION ROTATES THROUGH SOUTHERN MN/IA ON FRIDAY. THIS GIVES PORTIONS OF NORTHEAST IA/SOUTHEAST MN A SLIGHT CHANCE OF EARLY MORNING LIGHT SNOW AND DAYTIME RAIN. OTHERWISE...PLAN ON HIGHS IN THE AGAIN IN THE 40S TO A FEW LOWER 50S ACROSS FAR NORTHEAST IA/SOUTHWEST WI. A CHANCE OF RAIN ENTERS THE PICTURE FOR SATURDAY AFTERNOON THROUGH SUNDAY NIGHT AS A MID-LEVEL TROUGH AND WEAK SURFACE COLD FRONT PUSH SLOWLY EAST ACROSS THE AREA. LOOK FOR HIGHS SATURDAY AND SUNDAY IN THE 50S. THERE MAY BE A FEW LINGERING SHOWER ACROSS CENTRAL WI ON MONDAY BUT THE REST OF THE AREA WILL SEE MOSTLY SUNNY SKIES AS MID/UPPER LEVEL RIDGE BUILDS INTOTHE AREA. THIS WARMS HIGHS INTO THE UPPER 50S TO THE LOWER 60S. LOOK FOR THIS RIDGE TO PERSIST INTO TUESDAY FOR MOSTLY SUNNY CONDITIONS AND HIGHS TOPPING OFF AGAIN IN THE UPPER 50S TO LOWER 60S...OR RIGHT AROUND NORMAL LEVELS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 1213 AM CDT WED APR 16 2014 A 6 TO 10K DECK OF CLOUDS WILL LINGER ACROSS THE AREA THROUGH WEDNESDAY...AND THEN CEILINGS WILL BECOME MVFR AFTER 18.03Z AS WRAP AROUND LOW LEVEL MOISTURE MOVES INTO THE AREA ON THE BACKSIDE OF THE LOW. SOUTHEAST SUSTAINED WINDS WILL BE IN THE 15 TO 30 KNOT RANGE WITH 30 TO 35 KNOT GUSTS AT BOTH TAF SITES FROM 17.14Z THROUGH 18.02Z. THIS IS ASSOCIATED WITH THE TIGHTENING PRESSURE GRADIENT IN THE WARM SECTOR OF THE LOW PRESSURE SYSTEM THAT WILL BE MOVING FROM SOUTH CENTRAL MINNESOTA INTO NORTHEAST WISCONSIN. && .HYDROLOGY... ISSUED AT 411 AM CDT WED APR 16 2014 RIVERS REMAIN AT ELEVATED LEVELS FROM HEAVIER RAINFALL THIS PAST WEEKEND. FLOOD WARNINGS REMAIN IN EFFECT FOR THE SOUTHERN REACHES OF THE KICKAPOO RIVER AT GAYS MILLS AND STEUBEN. A FLOOD WARNING IS ALSO IN EFFECT FOR THE MISSISSIPPI AT WABASHA AND MCGREGOR. SEE WWW.WEATHER.GOV/AHPS2/INDEX.PHP?WFO=ARX FOR LATEST RIVER LEVELS AND FORECASTS. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...WINTER WEATHER ADVISORY FROM 7 AM THIS MORNING TO 7 AM CDT THURSDAY FOR WIZ017-029. MN...NONE. IA...NONE. && $$ SHORT TERM...DAS LONG TERM...DAS AVIATION...BOYNE HYDROLOGY...DAS
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
830 AM PDT WED APR 16 2014 .SYNOPSIS...DRY CONDITIONS WILL CONTINUE THROUGH THE WEEKEND. PATCHY FOG AND CLOUDS NEAR THE COAST WILL BECOME MORE EXTENSIVE THURSDAY NIGHT AND FRIDAY AS A WEAK WEATHER SYSTEM MOVES ONSHORE. A STRONGER LOW PRESSURE SYSTEM WILL ARRIVE LATE MONDAY AND TUESDAY BRINGING A THREAT FOR SHOWERS...COLDER TEMPERATURES...AND GUSTY WINDS. && .DISCUSSION...AS OF 8:30 AM PDT WEDNESDAY...MINOR FORECAST UPDATE THIS MORNING WITH CLOUDS MOSTLY CONFINED AROUND MONTEREY BAY AND THROUGH THE SALINAS VALLEY. THE REASON? NORTHERLY SURFACE GRADIENT RAMPED UP TO OVER 7 MB OVERNIGHT HELPING TO PUSH THE STRATUS DECK TO THE SOUTH. MOSTLY SUNNY CONDITIONS ARE FORECAST FOR ALL AREA BY LATER THIS MORNING WITH WARM CONDITIONS INLAND -- UPPER 70S TO AROUND 90. AT THE COAST AN WEAK ONSHORE FLOW WILL CONTINUE WHICH WILL KEEP IT CLOSER TO THE 60S AND LOWER 70S. ONE EXCEPTION WILL BE FOR PARTS OF SANTA CRUZ WHERE THE NORTHERLY FLOW WILL DOWNSLOPE AND HELP TO PUSH HIGHS 75-80. QUIET WEATHER WILL CONTINUE THROUGH THE REST OF THE WEEK INTO MONDAY BEFORE A BIG CHANGE HITS US ON TUESDAY. GOOD MODEL AGREEMENT THAT A COLD SYSTEM WILL DROP DOWN TO OUR AREA HELPING TO DROP 700 MB TEMPS TO THE -9 TO -11C RANGE. MOISTURE AVAILABILITY IS THE ONE BIG QUESTION MARK, ALTHOUGH SOME SHOWERS SHOULD BE GENERATED. IF THE MODELS VERIFY SNOW LEVELS WILL DROP TO UNDER 4000 FEET AND INSTABILITY WILL GREATLY INCREASE LEADING TO SOME THUNDERSTORMS AS WELL. WINDS WILL ALSO BECOME GUSTY FROM THE NORTH. UNLESS THERE IS A HUGE CHANGE IN THE MODELS, TEMPS WILL BE LOWERED FOR TUESDAY INTO WEDNESDAY ESPECIALLY FOR THE HILLS. STILL NEARLY A WEEK OUT, BUT IT`S VERY INTERESTING FOR A LATE APRIL SYSTEM! .PREVIOUS DISCUSSION...TONIGHTS VIIRS SATELLITE IMAGERY AROUND 230 AM SHOWED PATCHY LOW CLOUDS NEAR MONTEREY BAY AND SALINAS VALLEY. LATEST GOES FOG PRODUCT IMAGERY INDICATING STRATUS HAS BECOME A LITTLE MORE WIDESPREAD IN THE SALINAS VALLEY...NEAR HALF MOON BAY...AND MONTEREY BAY THE LAST COUPLE HOURS. BREEZY NORTHWEST WINDS OVER THE OPEN WATERS HAVE KEPT THE BOUNDARY LAYER WELL MIXED AND CONFINED STRATUS TO CONVERGENCE AND UPSLOPE AREAS NEAR THE COAST FAVORED BY NW WINDS. SHORT WAVE RIDGE WILL PROGRESS EASTWARD ACROSS THE STATE TODAY...KEEPING THE MARINE LAYER UNDER 1500 FEET. SURFACE PRESSURE GRADIENTS WILL REMAIN STRONG FROM THE NORTHWEST TO SOUTHEAST WITH SFO-ACV OVER 6 MB TODAY AND WINDS WILL REMAIN AT LEAST BREEZY OVER THE OPEN WATERS. HRRR MODEL SURFACE RH FIELD INDICATES LIMITED STRATUS AGAIN TODAY. AS THE RIDGE SHIFTS EASTWARD THE FLOW WILL BECOME MORE ONSHORE THURSDAY WITH A BETTER ESTABLISHED MARINE LAYER...SO EXPECT EXTENSIVE STRATUS TO RETURN TO COASTAL AREAS BY THURSDAY MORNING. A WEAK TROF IN ZONAL FLOW WILL APPROACH THE COAST THURSDAY NIGHT DEEPENING THE MARINE LAYER AND INCREASING ONSHORE FLOW. THIS TROF SPLITS OVER THE AREA FRIDAY...AND THE LACK OF UPPER LEVEL LIFT SHOULD KEEP CONDITIONS DRY. COOLER AIR ALOFT WITH 850 MB TEMPERATURES DROPPING TO 10 DEG C SHOULD DISRUPT THE MARINE LAYER FRIDAY BUT SPREAD COOLER AIR INLAND WITH CONTINUED ONSHORE FLOW. AFTER A BRIEF BREAK SATURDAY UNDER WEAK HIGH PRESSURE AND MOSTLY CLEAR SKIES...ANOTHER MINOR SYSTEM WILL BRUSH BY TO THE NORTH OF OUR AREA SUNDAY WITH MORE COASTAL CLOUDS. A STRONGER TROF WILL DROP OVER CALIFORNIA LATE MONDAY AND TUESDAY BRINGING A THREAT FOR SHOWERS AND MUCH COOLER CONDITIONS WITH GUSTY WINDS. FORECAST MODELS ARE CONSISTENTLY ADVERTISING THIS STRONGER SYSTEM...AND EVEN THOUGH THE SYSTEM LACKS A SIGNIFICANT MOISTURE TAP...COLD AIR ALOFT WILL BE PLENTIFUL AND SHOWERS ARE CERTAINLY POSSIBLE ESPECIALLY OVER THE MOUNTAINS. && .AVIATION...AS OF 4:30 AM PDT WEDNESDAY...SATELLITE IMAGERY SHOWS PATCHY LOW CLOUDS IN MRY BAY AND IN THE SALINAS VALLEY AND ALONG THE SAN MATEO COAST THIS MORNING. STRONG N-S PRESSURE GRADIENT INDICATES DRY NORTHERLY FLOW THAT WILL KEEP CLOUDS OUT OF THE SFO BAY AREA TODAY. VICINITY OF KSFO...VFR. WEST AFTERNOON WINDS TO 20 KT AFTER 20Z. KSFO BRIDGE APPROACH...SIMILAR TO KSFO. MONTEREY BAY AREA TERMINALS...MVFR CIGS THROUGH 17-18Z. && .MTR WATCHES/WARNINGS/ADVISORIES... .TDAY...SCA...PIGEON PT TO PT PINOS 0-10 NM GLW...PT ARENA TO PT REYES 10-60 NM GLW...PT REYES TO PIGEON PT 10-60 NM SCA...PT ARENA TO PT REYES 0-10 NM SCA...PT REYES TO PIGEON PT 0-10 NM SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM SCA...PT PINOS TO PT PIEDRAS BLANCAS 10-60 NM GLW...PIGEON PT TO PT PINOS 10-60 NM SCA...MONTEREY BAY FROM 1 PM && $$ PUBLIC FORECAST: BELL/KBB AVIATION: W PI VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO FOLLOW US ON FACEBOOK, TWITTER, AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.SANFRANCISCOBAYAREA.GOV WWW.TWITTER.COM/NWSBAYAREA WWW.YOUTUBE.COM/NWSBAYAREA
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
434 AM PDT WED APR 16 2014 .SYNOPSIS...DRY CONDITIONS WILL CONTINUE THROUGH THE WEEKEND. PATCHY FOG AND CLOUDS NEAR THE COAST WILL BECOME MORE EXTENSIVE THURSDAY NIGHT AND FRIDAY AS A WEAK WEATHER SYSTEM MOVES ONSHORE. A STRONGER LOW PRESSURE SYSTEM WILL ARRIVE LATE MONDAY AND TUESDAY BRINGING A THREAT FOR SHOWERS...COOLER TEMPERATURES...AND GUSTY WINDS. && .DISCUSSION...AS OF 03:53 AM PDT WEDNESDAY...TONIGHTS VIIRS SATELLITE IMAGERY AROUND 230 AM SHOWED PATCHY LOW CLOUDS NEAR MONTEREY BAY AND SALINAS VALLEY. LATEST GOES FOG PRODUCT IMAGERY INDICATING STRATUS HAS BECOME A LITTLE MORE WIDESPREAD IN THE SALINAS VALLEY...NEAR HALF MOON BAY...AND MONTEREY BAY THE LAST COUPLE HOURS. BREEZY NORTHWEST WINDS OVER THE OPEN WATERS HAVE KEPT THE BOUNDARY LAYER WELL MIXED AND CONFINED STRATUS TO CONVERGENCE AND UPSLOPE AREAS NEAR THE COAST FAVORED BY NW WINDS. SHORT WAVE RIDGE WILL PROGRESS EASTWARD ACROSS THE STATE TODAY...KEEPING THE MARINE LAYER UNDER 1500 FEET. SURFACE PRESSURE GRADIENTS WILL REMAIN STRONG FROM THE NORTHWEST TO SOUTHEAST WITH SFO-ACV OVER 6 MB TODAY AND WINDS WILL REMAIN AT LEAST BREEZY OVER THE OPEN WATERS. HRRR MODEL SURFACE RH FIELD INDICATES LIMITED STRATUS AGAIN TODAY. AS THE RIDGE SHIFTS EASTWARD THE FLOW WILL BECOME MORE ONSHORE THURSDAY WITH A BETTER ESTABLISHED MARINE LAYER...SO EXPECT EXTENSIVE STRATUS TO RETURN TO COASTAL AREAS BY THURSDAY MORNING. A WEAK TROF IN ZONAL FLOW WILL APPROACH THE COAST THURSDAY NIGHT DEEPENING THE MARINE LAYER AND INCREASING ONSHORE FLOW. THIS TROF SPLITS OVER THE AREA FRIDAY...AND THE LACK OF UPPER LEVEL LIFT SHOULD KEEP CONDITIONS DRY. COOLER AIR ALOFT WITH 850 MB TEMPERATURES DROPPING TO 10 DEG C SHOULD DISRUPT THE MARINE LAYER FRIDAY BUT SPREAD COOLER AIR INLAND WITH CONTINUED ONSHORE FLOW. AFTER A BRIEF BREAK SATURDAY UNDER WEAK HIGH PRESSURE AND MOSTLY CLEAR SKIES...ANOTHER MINOR SYSTEM WILL BRUSH BY TO THE NORTH OF OUR AREA SUNDAY WITH MORE COASTAL CLOUDS. A STRONGER TROF WILL DROP OVER CALIFORNIA LATE MONDAY AND TUESDAY BRINGING A THREAT FOR SHOWERS AND MUCH COOLER CONDITIONS WITH GUSTY WINDS. FORECAST MODELS ARE CONSISTENTLY ADVERTISING THIS STRONGER SYSTEM...AND EVEN THOUGH THE SYSTEM LACKS A SIGNIFICANT MOISTURE TAP...COLD AIR ALOFT WILL BE PLENTIFUL AND SHOWERS ARE CERTAINLY POSSIBLE ESPECIALLY OVER THE MOUNTAINS. && .AVIATION...AS OF 4:30 AM PDT WEDNESDAY...SATELLITE IMAGERY SHOWS PATCHY LOW CLOUDS IN MRY BAY AND IN THE SALINAS VALLEY AND ALONG THE SAN MATEO COAST THIS MORNING. STRONG N-S PRESSURE GRADIENT INDICATES DRY NORTHERLY FLOW THAT WILL KEEP CLOUDS OUT OF THE SFO BAY AREA TODAY. VICINITY OF KSFO...VFR. WEST AFTERNOON WINDS TO 20 KT AFTER 20Z. KSFO BRIDGE APPROACH...SIMILAR TO KSFO. MONTEREY BAY AREA TERMINALS...MVFR CIGS THROUGH 17-18Z. && .MTR WATCHES/WARNINGS/ADVISORIES... .TDAY...SCA...PIGEON PT TO PT PINOS 0-10 NM SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM GLW...PT ARENA TO PT REYES 10-60 NM GLW...PT REYES TO PIGEON PT 10-60 NM SCA...PIGEON PT TO PT PINOS 10-60 NM SCA...PT PINOS TO PT PIEDRAS BLANCAS 10-60 NM SCA...PT ARENA TO PT REYES 0-10 NM SCA...PT REYES TO PIGEON PT 0-10 NM SCA...MONTEREY BAY FROM 1 PM && $$ PUBLIC FORECAST: KBB AVIATION: W PI VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO FOLLOW US ON FACEBOOK, TWITTER, AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.SANFRANCISCOBAYAREA.GOV WWW.TWITTER.COM/NWSBAYAREA WWW.YOUTUBE.COM/NWSBAYAREA
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
429 AM PDT WED APR 16 2014 .SYNOPSIS...DRY CONDITIONS WILL CONTINUE THROUGH THE WEEKEND. PATCHY FOG AND CLOUDS NEAR THE COAST WILL BECOME MORE EXTENSIVE THURSDAY NIGHT AND FRIDAY AS A WEAK WEATHER SYSTEM MOVES ONSHORE. A STRONGER LOW PRESSURE SYSTEM WILL ARRIVE LATE MONDAY AND TUESDAY BRINGING A THREAT FOR SHOWERS...COOLER TEMPERATURES...AND GUSTY WINDS. && .DISCUSSION...AS OF 03:53 AM PDT WEDNESDAY...TONIGHTS VIIRS SATELLITE IMAGERY AROUND 230 AM SHOWED PATCHY LOW CLOUDS NEAR MONTEREY BAY AND SALINAS VALLEY. LATEST GOES FOG PRODUCT IMAGERY INDICATING STRATUS HAS BECOME A LITTLE MORE WIDESPREAD IN THE SALINAS VALLEY...NEAR HALF MOON BAY...AND MONTEREY BAY THE LAST COUPLE HOURS. BREEZY NORTHWEST WINDS OVER THE OPEN WATERS HAVE KEPT THE BOUNDARY LAYER WELL MIXED AND CONFINED STRATUS TO CONVERGENCE AND UPSLOPE AREAS NEAR THE COAST FAVORED BY NW WINDS. SHORT WAVE RIDGE WILL PROGRESS EASTWARD ACROSS THE STATE TODAY...KEEPING THE MARINE LAYER UNDER 1500 FEET. SURFACE PRESSURE GRADIENTS WILL REMAIN STRONG FROM THE NORTHWEST TO SOUTHEAST WITH SFO-ACV OVER 6 MB TODAY AND WINDS WILL REMAIN AT LEAST BREEZY OVER THE OPEN WATERS. HRRR MODEL SURFACE RH FIELD INDICATES LIMITED STRATUS AGAIN TODAY. AS THE RIDGE SHIFTS EASTWARD THE FLOW WILL BECOME MORE ONSHORE THURSDAY WITH A BETTER ESTABLISHED MARINE LAYER...SO EXPECT EXTENSIVE STRATUS TO RETURN TO COASTAL AREAS BY THURSDAY MORNING. A WEAK TROF IN ZONAL FLOW WILL APPROACH THE COAST THURSDAY NIGHT DEEPENING THE MARINE LAYER AND INCREASING ONSHORE FLOW. THIS TROF SPLITS OVER THE AREA FRIDAY...AND THE LACK OF UPPER LEVEL LIFT SHOULD KEEP CONDITIONS DRY. COOLER AIR ALOFT WITH 850 MB TEMPERATURES DROPPING TO 10 DEG C SHOULD DISRUPT THE MARINE LAYER FRIDAY BUT SPREAD COOLER AIR INLAND WITH CONTINUED ONSHORE FLOW. AFTER A BRIEF BREAK SATURDAY UNDER WEAK HIGH PRESSURE AND MOSTLY CLEAR SKIES...ANOTHER MINOR SYSTEM WILL BRUSH BY TO THE NORTH OF OUR AREA SUNDAY WITH MORE COASTAL CLOUDS. A STRONGER TROF WILL DROP OVER CALIFORNIA LATE MONDAY AND TUESDAY BRINGING A THREAT FOR SHOWERS AND MUCH COOLER CONDITIONS WITH GUSTY WINDS. FORECAST MODELS ARE CONSISTENTLY ADVERTISING THIS STRONGER SYSTEM...AND EVEN THOUGH THE SYSTEM LACKS A SIGNIFICANT MOISTURE TAP...COLD AIR ALOFT WILL BE PLENTIFUL AND SHOWERS ARE CERTAINLY POSSIBLE ESPECIALLY OVER THE MOUNTAINS. && .AVIATION...AS OF 10:50 PM PDT TUESDAY...SATELLITE IMAGERY SHOWS MOSTLY CLEAR SKIES OVER THE AREA EXCEPT FOR PATCHY STRATUS NEAR THE MONTEREY BAY. THE NORTH TO SOUTH SURFACE PRESSURE GRADIENT HAS RAMPED UP TO WELL OVER 6 MB FROM ACV TO SFO...THUS EXPECT LESS IN THE WAY OF STRATUS IMPACTS ACROSS THE BAY AREA TAF LOCATIONS TONIGHT. THERE COULD BE SOME CIGS OVER SAN JOSE AND OAKLAND LATE...AND STRATUS WILL IMPACT THE MONTEREY AND SALINAS TERMINALS OVERNIGHT. VICINITY OF KSFO...VFR IS EXPECTED TO PERSIST THROUGH THE FORECAST PERIOD WITH MVFR CONDITIONS DEVELOPING LATE TO THE EAST OF THE TERMINAL AND APPROACH. KSFO BRIDGE APPROACH...SIMILAR TO KSFO. MONTEREY BAY AREA TERMINALS...MVFR CIGS BECOMING LOCALLY IFR LATE. CLEARING EXPECTED BY 18Z WEDNESDAY WITH INCREASING NORTHWEST WINDS. && .MTR WATCHES/WARNINGS/ADVISORIES... .TDAY...SCA...PIGEON PT TO PT PINOS 0-10 NM SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM GLW...PT ARENA TO PT REYES 10-60 NM GLW...PT REYES TO PIGEON PT 10-60 NM SCA...PIGEON PT TO PT PINOS 10-60 NM SCA...PT PINOS TO PT PIEDRAS BLANCAS 10-60 NM SCA...PT ARENA TO PT REYES 0-10 NM SCA...PT REYES TO PIGEON PT 0-10 NM SCA...MONTEREY BAY FROM 1 PM && $$ PUBLIC FORECAST: KBB AVIATION: SIMS VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO FOLLOW US ON FACEBOOK, TWITTER, AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.SANFRANCISCOBAYAREA.GOV WWW.TWITTER.COM/NWSBAYAREA WWW.YOUTUBE.COM/NWSBAYAREA
AREA FORECAST DISCUSSION
NWS MIAMI FL
957 AM EDT WED APR 16 2014 .UPDATE... THE COLD FRONT THAT MOVED ACROSS SOUTH FLORIDA LAST EVENING HAS NOW STALLED ACROSS THE FLORIDA STRAITS AND WILL MOVE LITTLE THROUGH THIS AFTERNOON. DUE TO THE PROXIMITY OF THE FRONT AND HIGH PRESSURE BUILDING TO THE NORTH, THE WIND WILL GRADUALLY SHIFT TO THE NORTHEAST THIS AFTERNOON AND ALLOW FOR A FEW SHOWERS TO POSSIBLY DEVELOP OVER THE ATLANTIC THIS AFTERNOON AND MOVE ONSHORE. MOST OF THE ACTIVITY IS EXPECTED ACROSS THE SOUTHERN PORTIONS. THE 12Z MFL SOUNDING ALSO SHOWS THE AVAILABLE MOISTURE FOR THE FLOW TO ENCOUNTER AND AID IN THE SHOWER DEVELOPMENT. ONLY MARGINAL INSTABILITY EXISTS BUT AS TEMPERATURES WARM INTO THE LOWER 80S THIS AFTERNOON ACROSS INLAND BROWARD/MIAMI-DADE COUNTIES AND MAINLAND MONROE COUNTY THE LOW LEVEL INSTABILITY WILL INCREASE SLIGHTLY. THIS COULD LEAD TO DEVELOPMENT OF ADDITIONAL SHOWERS IN THOSE AREAS WITH THE HRRR INDICATING THIS AND EVEN A VERY SLIGHT CHANCE FOR LIGHTNING. CURRENT THINKING IS THE PROBABILITY OF LIGHTNING IS TOO LOW BUT MAY NEED TO INCLUDE THE SLIGHT CHANCE IF PATTERNS APPEAR TO BE CHANGING AS THE AFTERNOON PROGRESSES. KOB && .PREV DISCUSSION... /ISSUED 813 AM EDT WED APR 16 2014/ SHORT TERM (TODAY THROUGH FRIDAY NIGHT)... A STATIONARY FRONT OVER THE KEYS WILL START TO MOVE BACK NORTH AS A WARM FRONT TONIGHT AND THROUGH SOUTH FLORIDA ON THURSDAY. THIS WILL ALLOW FOR SURFACE WINDS TO BE NORTH TO NORTHEAST TODAY OVER SOUTH FLORIDA BEFORE SWINGING TO AN EASTERLY DIRECTION TONIGHT AND TO A EAST SOUTHEAST DIRECTION ON THURSDAY. AT THE SAME TIME...THE MID TO UPPER LEVEL WINDS WILL BECOME MORE SOUTHWEST OVER SOUTH FLORIDA TONIGHT INTO THURSDAY. THESE WINDS WILL ALLOW FOR AN OVERRUNNING SET UP OVER THE SOUTHERN PORTION OF SOUTH FLORIDA THIS AFTERNOON INTO THIS EVENING BEFORE SPREADING NORTHWARD INTO THE REST OF SOUTH FLORIDA TONIGHT INTO THURSDAY. SO WILL KEEP THE POPS IN A SLIGHT CHANCE OVER MOST OF SOUTH FLORIDA TODAY...EXCEPT A CHANCE OVER THE SOUTHERN AREAS OF SOUTH FLORIDA. THE POPS WILL THEN BE RAISED TO CHANCE CATEGORY OVER ALL OF SOUTH FLORIDA TONIGHT INTO THURSDAY. THERE COULD EVEN BE A FEW ELEVATED THUNDERSTORMS OVER THE SOUTHERN AREAS LATE TONIGHT BEFORE EXPANDING INTO ALL OF SOUTH FLORIDA ON THURSDAY AS THE 500 MB TEMP COOLS DOWN TO -12C OVER SOUTH FLORIDA. SO WILL CONTINUE TO CARRY A SLIGHT CHANCE OF THUNDERSTORMS OVER THE SOUTHERN AREAS LATE TONIGHT...AND ALL OF SOUTH FLORIDA ON THURSDAY. THE WARM FRONT WILL CONTINUE TO MOVE NORTHWARD THURSDAY NIGHT INTO FRIDAY INTO CENTRAL FLORIDA...AS LOW PRESSURE DEVELOPS OVER THE NORTHERN GULF OF MEXICO. THIS WILL ALLOW FOR MORE OF A SOUTHERLY WIND FLOW OVER SOUTH FLORIDA ON FRIDAY BRINGING IN DEEPER MOISTURE TO THE AREA. SO WILL INCREASE THE POPS A LITTLE BIT FOR FRIDAY WITH LIKELY POPS OVER THE LAKE OKEECHBOEE REGION AND PALM BEACH COUNTY AREA WITH CHANCE POPS OVER THE REST OF SOUTH FLORIDA. THUNDERSTORMS WILL ALSO BE POSSIBLE OVER SOUTH FLORIDA ON FRIDAY...DUE TO A SHORT WAVE MOVING TOWARDS THE AREA FROM THE WEST. THE LOW PRESSURE SYSTEM WILL MOVE EAST ACROSS NORTHERN FLORIDA FRIDAY NIGHT PUSHING THE FRONT BACK SOUTHWARD AS A COLD FRONT THROUGH SOUTH FLORIDA. AT THE SAME TIME...THE SHORT WAVE WILL BE MOVING THROUGH SOUTH FLORIDA FRIDAY NIGHT ALONG WITH THE 500 MB TEMPS REMAINING COOL IN THE -10 TO -12C RANGE. SO WILL CONTINUE THE CHANCE POPS OVER SOUTH FLORIDA FRIDAY NIGHT ALONG WITH SOME THUNDERSTORMS. LONG TERM (SATURDAY THROUGH TUESDAY)... THE LOW WILL CONTINUE TO MOVE EAST THROUGH THE WESTERN ATLANTIC WATERS THIS WEEKEND. THIS WILL CONTINUE TO PUSH THE COLD FRONT SOUTHWARD INTO THE FLORIDA STRAITS THIS WEEKEND AND ALLOW FOR HIGH PRESSURE TO BUILD INTO THE AREA FROM THE CENTRAL UNITED STATES. SO THE THERE COULD BE A FEW SHOWERS OVER SOUTH FLORIDA SATURDAY MORNING BEFORE DRYING OUT SATURDAY AFTERNOON INTO SUNDAY. THE HIGH WILL THEN MOVE SLOWLY EAST INTO THE WESTERN ATLANTIC WATERS EARLY NEXT WEEK ALLOWING FOR THE DRY WEATHER TO REMAIN IN PLACE FOR EARLY NEXT WEEK OVER SOUTH FLORIDA. AVIATION... MVFR STRATUS IMPACTING ALL BUT MIAMI-DADE TERMINALS AT 12Z...AND LOW CIGS WILL LIKELY IMPACT ALL TERMINALS THROUGH AT LEAST 16Z. THEREAFTER...LOOK FOR DIURNAL MIXING TO SCOUR SOME CLOUDS AWAY. SCATTERED SHOWERS SHOULD GENERALLY HOLD OFF UNTIL EVENING...WHEN VCSH IS FORECAST. UNTIL THEN...ONLY ISOLATED SHOWERS ANTICIPATED. MODELS TRENDING TOWARD AN EXTENDED PERIOD OF MVFR CIGS TONIGHT...FOR NOW KEPT CLOUDS ABOVE 3KFT. MARINE... THE WIND DIRECTION OVER THE SOUTH FLORIDA LOCAL WATERS WILL BE NORTHERLY TODAY BEFORE SWINGING TO A EASTERLY DIRECTION TONIGHT INTO THURSDAY...BEFORE CONTINUING TO SWING TO A SOUTHERLY DIRECTION ON FRIDAY. THE WIND SPEEDS OVER THE SOUTH FLORIDA LOCAL WATERS WILL BE 15 KNOTS OR LESS TODAY INTO FRIDAY. THERE COULD BE SOME SMALL NORTHEAST SWELLS OVER THE PALM BEACH WATERS LATE TONIGHT INTO THURSDAY BEFORE SUBSIDING BY THURSDAY NIGHT. SO THE SEAS IN THE PALM BEACH WATERS SHOULD BUILD TO 7 FEET LATE TONIGHT INTO THURSDAY...BEFORE SUBSIDING BELOW 7 FEET THURSDAY NIGHT INTO FRIDAY. REST OF THE ATLANTIC SEAS WILL REMAIN BELOW 7 FEET ALONG WITH THE GULF SEAS. CLIMATE... YESTERDAY...APRIL 15...MIAMI TIED A DAILY HIGH MINIMUM OF 76F...LAST REACHED IN 1999. && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 80 72 83 72 / 20 30 50 40 FORT LAUDERDALE 81 75 84 75 / 30 40 50 30 MIAMI 82 74 85 74 / 40 50 50 30 NAPLES 83 68 87 68 / 20 30 50 40 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$
AREA FORECAST DISCUSSION...CORRECTED
NWS LINCOLN IL
1024 AM CDT WED APR 16 2014 .DISCUSSION... ISSUED 1021 AM CDT WED APR 16 2014 LOW PRESSURE IN SOUTH DAKOTA WILL MOVE EAST INTO IOWA AND THEN NORTHEAST TOWARD LAKE HURON. AS IT PROGRESSES, A WARM FRONT WILL LIFT ACROSS IL, PUTTING OUR FORECAST AREA IN THE WARM SECTOR BY THIS EVENING. DURING THE DAY, SOUTHERLY WINDS WILL INCREASE AS THE PRESSURE GRADIENT TIGHTENS BETWEEN DEPARTING HIGH PRESSURE AND THE SD LOW. 12Z RAP FORECAST SOUNDINGS SHOW MIXING HEIGHTS UP TO 825-850 MB. THAT SHOULD ALLOW MOMENTUM TRANSFER OF WIND SPEEDS AROUND 25 MPH WITH SOME GUSTS TO 35 MPH. WE EXPECT TO REMAIN BELOW WIND ADVISORY CRITERIA OF 30-39 MPH SUSTAINED WINDS FOR AN HOUR OR MORE. PEAK WINDS APPEAR TO BE IN THE NOON TO 3 PM TIME FRAME. MIXING OF DRY AIR FROM THE MID LEVELS WILL HELP THE SURFACE TEMPS CLIMB ABOUT 10 TO 15 DEG WARMER THAN YESTERDAY. LIGHTLY FILTERED SUNSHINE WILL ALSO HELP BOOST HIGH TEMPS, WITH READINGS IN THE MID TO UPPER 50S BY 3-4 PM. WE SHOULD REMAIN DRY UNTIL THE COLD FRONT PUSHES ACROSS IL SOMETIME LATE THURSDAY/THURSDAY NIGHT. STILL, LIMITED MOISTURE WILL KEEP RAIN CHANCES AND AMOUNTS ON THE LOW SIDE. OUR CURRENT FORECAST GRIDS LOOK ON TRACK OVER THE NEXT 12-24 HOURS, ESPECIALLY TEMPS, DEWPOINTS, WINDS AND SKY. NO FORMAL UPDATE WILL BE NEEDED THIS MORNING. SHIMON && .AVIATION... ISSUED 556 AM CDT WED APR 16 2014 LITTLE CHANGE NEEDED TO PREVIOUS TAF SET. WIND WILL BE THE MAIN CONCERN THROUGH THIS AFTERNOON. SOUTHERLY WIND GUSTS AROUND 30 KNOTS ARE EXPECTED TO DEVELOP NEAR ALL TAF SITES BY LATE MORNING, AND CONTINUE THROUGH THE AFTERNOON. MAY SEE SOME EVEN HIGHER AT KPIA. WE WILL LOSE THE GUSTS WITH SUNSET, BUT SUSTAINED WINDS WILL STILL AVERAGE AROUND 15 KNOTS MUCH OF THE NIGHT. LATE IN THE PERIOD, WINDS WILL START TO SHIFT MORE TO THE SOUTHWEST, AHEAD OF A COLD FRONT WHICH WILL MOVE THROUGH THE AREA LATER ON THURSDAY. GEELHART && .PREV DISCUSSION... ISSUED 249 AM CDT WED APR 16 2014 SHORT TERM...TODAY THROUGH FRIDAY WINDS WILL INCREASE MARKEDLY ACROSS CENTRAL ILLINOIS TODAY AS GRADIENT TIGHTENS BETWEEN DEPARTING HIGH PRESSURE SYSTEM AND LOW TRACKING FROM THE DAKOTAS INTO SOUTHERN MINNESOTA. MODELS ARE NOT QUITE AS STRONG WITH THE WINDS AS THEY WERE IN PREVIOUS RUNS, SO AM NOT CONCERNED ABOUT REACHING WIND ADVISORY CRITERIA. BUFKIT MOMENTUM TRANSFER AT KPIA SHOWS 33KT WINDS AT THE TOP OF THE MIXED LAYER THIS AFTERNOON, AS OPPOSED TO 43KT ON THE PRIOR RUN JUST 24 HOURS AGO. DESPITE THIS DECREASE IN MOMENTUM, THINK S/SE WINDS WILL GUST TO BETWEEN 30 AND 35MPH ACROSS THE WESTERN HALF OF THE KILX CWA, WITH GUSTS TO AROUND 25MPH FURTHER EAST NEAR THE INDIANA BORDER. THIS STRONG SOUTHERLY FLOW WILL HELP BRING MUCH WARMER AIR INTO THE REGION. EXTENT OF WARMING WILL BE MITIGATED SOMEWHAT BY AN EASTERLY COMPONENT TO THE WIND AND MIXING HEIGHTS LOWERING TO LESS THAN 5000FT. RESULTING AFTERNOON HIGHS WILL RANGE FROM THE MIDDLE 50S EAST TO AROUND 60 FAR WEST. AS SOUTHERN MINNESOTA LOW LIFTS TOWARD LAKE SUPERIOR, IT WILL DRAG A WEAK COLD FRONT INTO THE ILLINOIS RIVER VALLEY BY DAWN THURSDAY. THIS BOUNDARY WILL BECOME STATIONARY ALONG THE I-55 CORRIDOR DURING THE DAY THURSDAY, CREATING LITTLE IN THE WAY OF SENSIBLE WEATHER. A MID-LEVEL SHORT-WAVE WILL APPROACH FROM THE SOUTHWEST LATE IN THE DAY AND WILL EVENTUALLY INTERACT WITH THE FRONT TO PERHAPS PRODUCE A FEW LIGHT SHOWERS. CURRENT SURFACE ANALYSIS SHOWS A VERY DRY AIR MASS HAS SETTLED ACROSS THE EASTERN HALF OF THE CONUS ALL THE WAY TO THE GULF OF MEXICO. IN FACT, BUOYS IN THE NORTHERN GULF ARE CURRENTLY SHOWING DEW POINTS AS LOW AS THE MIDDLE TO UPPER 30S. WITH SO MUCH DRY AIR TO THE SOUTH, DO NOT THINK FRONT WILL HAVE ENOUGH MOISTURE TO WORK WITH IN ORDER TO PRODUCE PRECIP ACROSS THE AREA ON THURSDAY. GFS IS THE ONLY MODEL THAT IS HOLDING ON TO QPF ACROSS THE ILLINOIS RIVER VALLEY THURSDAY AFTERNOON, BUT THINK THIS IS OVERDONE. WILL THEREFORE GO WITH A DRY FORECAST ACROSS THE BOARD. THERE ARE EVEN SOME INDICATIONS THAT DRY CONDITIONS WILL CONTINUE THURSDAY NIGHT INTO FRIDAY AS THE UPPER WAVE ARRIVES. AT THIS POINT, WILL LEAVE CHANCE POPS FOR SHOWERS IN THE FORECAST THURSDAY NIGHT INTO FRIDAY MORNING AS SYNOPTIC LIFT ASSOCIATED WITH THE WAVE WILL LIKELY BE ENOUGH TO SQUEEZE A FEW LIGHT SHOWERS OUT OF THE DRY AIR MASS. ONCE THE WAVE PASSES, DRY WEATHER WILL RETURN FRIDAY AFTERNOON AND NIGHT. LONG TERM...SATURDAY THROUGH TUESDAY AFTER A WARM/DRY DAY ON SATURDAY, ATTENTION TURNS TO NEXT APPROACHING SYSTEM FOR EARLY NEXT WEEK. MODELS HAVE BEEN TRENDING SLOWER WITH ITS APPROACH, WITH MOST 00Z APR 16 GUIDANCE SUGGESTING EASTER SUNDAY MAY REMAIN LARGELY DRY. GFS IS THE MOST AGGRESSIVE MODEL IN DRIVING PRECIP EASTWARD INTO THE AREA, BUT EVEN IT HAS BACKED OFF AND KEEPS RAIN AT BAY UNTIL SUNDAY AFTERNOON AT THE EARLIEST. GEM FOCUSES BEST RAIN CHANCES SUNDAY NIGHT INTO MONDAY, WHILE ECMWF IS EVEN SLOWER AND ADVERTISES MAINLY A MONDAY RAIN EVENT. AS A RESULT OF THE DISTINCT SLOWING TREND, HAVE TRIMMED POPS ACCORDINGLY. WILL KEEP SATURDAY NIGHT AND SUNDAY MORNING DRY, THEN WILL BRING CHANCE POPS INTO THE PICTURE ACROSS THE WESTERN CWA SUNDAY AFTERNOON. WILL HIGHLIGHT THE SUNDAY NIGHT/MONDAY TIME FRAME WITH THE HIGHEST POPS, FOLLOWED BY A RETURN TO DRY WEATHER ON TUESDAY. ASIDE FROM THE EARLY WEEK RAIN CHANCES, THE EXTENDED FORECAST WILL FEATURE WARMER WEATHER, WITH MODEL GUIDANCE SUGGESTING TEMPS REACHING THE 70S BY TUESDAY. BARNES && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
649 AM CDT WED APR 16 2014 .SYNOPSIS... ISSUED AT 406 AM CDT WED APR 16 2014 HIGH PRESSURE RIDGE HAS MOVED INTO THE OHIO VLY WHILE A 998 MB SFC CYCLONE WAS LOCATED SOUTH OF PIERRE SD AT 07Z. SOUTHEAST WINDS ARE STRENGTHENING OVER THE AREA IN TIGHTENING PRESSURE GRADIENT RESULTING IN STEADY TO RISING TEMPS. PATTERN ALOFT FEATURES FAST SEMI-ZONAL FLOW OVER REGION AHEAD OF SHORTWAVE TRAVERSING NORTHERN ROCKIES. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 406 AM CDT WED APR 16 2014 CRITICAL FIRE WEATHER AND WIND ADVISORY CONCERNS DOMINATE THE FCST. SFC CYCLONE OVER SD WILL MOVE EAST INTO WI BY EARLY THURSDAY AM. TRAILING COLD FRONT WILL MOVE INTO CWA LATER THIS EVENING AND MOVE EAST AND SHOULD BE NEAR OR JUST EAST OF MISSISSIPPI RIVER BY 12Z THURSDAY. WARM SECTOR OF SYSTEM IS MOISTURE STARVED AND THUS MOST OF PCPN THAT OCCURS DURING PERIOD WILL BE RIGHT AHEAD AND NORTH OF SFC CYCLONE TRACK. WILL THOUGH HAVE SMALL CHCS FOR LIGHT RAIN WITH FRONT TONIGHT MAINLY NORTHEAST IA BEING IN CLOSER PROXIMITY TO PV ANOMALY AND VORTICITY ADVECTION. VERY STRONG LOW LEVEL JET WITH 850 MB WINDS OF 50-60 KTS TO FOCUS MAINLY WEST OF CWA THIS AM THEN SHIFT INTO AREAS WEST OF MISSISSIPPI RIVER THIS AFTN BUT WEAKENING TO NEAR 40 KTS. NONETHELESS...TIGHTENING PRESSURE GRADIENT AND DEEP MIXING TAPPING STRONGER WINDS ALOFT SHOULD GENERATE SUSTAINED SOUTHEAST TO SOUTH WINDS AT 20-25 KTS WITH GUSTS AROUND 35 KTS... CLOSE TO WIND ADVISORY CRITERIA WHICH WILL NEED TO BE MONITORED IN CASE AN ADVISORY BECOMES NEEDED...BUT ENOUGH UNCERTAINTY WITH CLOUDS AND POTENTIAL IMPACTS ON MIXING AND NOTED WEAKENING TRENDS ON WINDS ALOFT FROM LATEST RUC AND NAM TO HOLD OFF ON ISSUING ATTM. STRONG WINDS WILL AID IN ELEVATED FIRE DANGER TODAY...WITH MAIN CHALLENGE BEING LOW LEVEL MOISTURE AND MODELS HANDLING WHICH WILL LOOM LARGE AS TO WHETHER RED FLAG WARNING CRITERIA IS ACHIEVED IN SOME AREAS. DEEP MIXING TO AT OR ABOVE 800 MB IF REALIZED FROM NAM/RUC SOUNDINGS WOULD YIELD SUBSTANTIAL DROP IN DEWPTS INTO THE TEENS TO LOWER 20S ALL BUT FAR WESTERN CWA THIS AFTN. AND THESE LOW DEWPTS CERTAINTLY SHOW UP IN LOOKING BACK AT UPSTREAM OBS IN SIMILAR REGIME YSTDY. UNCERTAINTY WITH HOW MUCH RECENT HEAVY RAINS AND CONTINUED GREENING UP TO IMPACT OR OFFSET DRYING ATTENDANT TO DEEP MIXING. THIS IS DISCUSSED FURTHER IN FIRE WEATHER SECTION BELOW. HIGHS TODAY WITH MIXING AND PROGGED LOW LEVEL THICKNESS AND VERIFICATION FROM YSTDY ALONG WITH BOUTS OF MID/HIGH CLOUDINESS SUPPORT LOWERING MAXES FEW DEGS ESPECIALLY NORTHEAST 1/3-1/2. OVERALL... VERIFICATION SUPPORTS HIGHS RANGING FROM 50-55F NORTHEAST TO LOWER 60S SOUTHWEST. TEMPS MILD MOST OF TONIGHT HELD UP BY BREEZY SOUTH/SOUTHWEST WINDS WITH TEMPS FALLING LATE WITH FRONTAL PASSAGE WITH MID 30S WEST/NORTHWEST TO LOWER 40S EAST/SOUTHEAST. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 406 AM CDT WED APR 16 2014 FORECAST FOCUS IN THE EXTENDED IS ON CONTINUED BELOW NORMAL TEMPERATURES THROUGH THE REST OF THE WORK WEEK WITH SMALL PCPN CHANCES ACROSS THE SOUTHEAST THURSDAY NIGHT/FRIDAY MORNING. TEMPERATURES TO RETURN TO NORMAL THIS WEEKEND AND POSSIBLY ABOVE NORMAL EARLY NEXT WEEK. THURSDAY...WEAK COLD FRONT TO BE JUST EAST OF CWA IN THE MORNING WITH PARENT LOW LIFTING NORTHEAST INTO THE GREAT LAKES. LINGERING CLOUDS...WEST WINDS...AND MIXING TO AROUND 900MB WILL KEEP TEMPERATURES WELL BELOW NORMAL WITH AFTERNOON READINGS IN THE UPPER 40S NORTH TO MIDDLE 50S SOUTH. ONE CONCERN IS CLOUD TRENDS AND IF CLOUDS CLEAR OUT...THAN FORECAST MAX TEMPS MAY BE A FEW DEGREES TOO COLD. THURSDAY NIGHT-FRIDAY...SHORTWAVE TO TRACK OVER THE SOUTHERN PLAINS LIFTING NORTHEAST NEAR THE CWA AROUND MIDNIGHT. LOW LEVEL CONVERGENCE AND MOISTURE TRANSPORT INCREASES ACROSS THE FAR SOUTHEAST WITH LIGHT RAIN SHOWERS BREAKING OUT MAINLY SOUTH AND EAST OF A LINE FROM KIRKSVILLE MISSOURI TO PRINCETON ILLINOIS. MOISTURE AVAILABILITY IS VERY LIMITED SO QPF AMOUNTS WILL BE A FEW HUNDREDTHS OF AN INCH. ONE THING OF NOTE IS THE LATEST NAM SOLUTION HAS A NON-EVENT FOR THIS PERIOD WHICH WAS MUCH DIFFERENT THAN ITS PREVIOUS RUN. ANOTHER VERY INTERESTING THING IS THAT THE NEW 00Z NAM/GFS BOTH HAVE A SHORTWAVE COMING DOWN FROM CANADA IMPACTING THE CWA WITH CLOUDS AND PCPN CHANCES FRIDAY. THE NON-AMERICAN SOLUTIONS (ECMWF/GEM/UKMET) ALL SAY OTHERWISE AND HAVE DRY FORECASTS. SIDED WITH THE NON-AMERICAN SOLUTIONS GIVEN THAT THE NAM/GFS HAVE BEEN NOTORIOUSLY TOO MOIST IN THE LOW LEVELS THIS SPRING. HIGH TEMPERATURES FRIDAY TO BE A LITTLE WARMER THAN THURSDAY BUT STILL BELOW NORMAL. THIS WEEKEND...MODELS CONTINUE TO SHOW A STORM SYSTEM TRACKING ACROSS SOUTHERN CANADA WITH A COLD FRONT MOVING ACROSS THE MIDWEST. AHEAD OF THIS FRONT...TEMPERATURES WILL WARM NICELY WITH 85H TEMPS PROGGED TO BE IN THE +6 TO 10C RANGE BY 00Z SUNDAY. HIGHS OVER THE WEEKEND TO BE IN UPPER 50S/LOW 60S SATURDAY AND IN THE 60S AREA WIDE ON SUNDAY. FORCING AND LOW LEVEL MOISTURE INCREASES SUNDAY AHEAD OF COLD FRONT WITH LIGHT TO POSSIBLY MODERATE RAIN FALLING SOMETIME DURING THE DAY. MODEL CONSENSUS HAS CHANCE POPS AT THIS TIME FOR SUNDAY. EARLY NEXT WEEK...WARM AND DRY CONDITIONS WILL BE FOUND AS HIGH PRESSURE DRIFTS ACROSS THE MIDWEST. TEMPERATURES TO AVERAGE ABOVE NORMAL WITH HIGHS WELL INTO THE 60S AND LOWER 70S. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING) ISSUED AT 639 AM CDT WED APR 16 2014 STRONG SOUTH WINDS WILL DEVELOP THIS MORNING THROUGH AFTERNOON AS LOW PRESSURE MOVES FROM SOUTH DAKOTA TO NORTH CENTRAL IOWA BY LATE AFTERNOON. SOUTH WINDS AT 15 TO 25 KTS GUSTING TO AROUND 30KTS ARE EXPECTED 14Z-17Z WITH SPEEDS INCREASING TO AROUND 25KTS WITH GUSTS AROUND 35KTS BY 17Z AND CONTINUING THROUGH THE AFTERNOON. CONTINUE TO MONITOR FOR LLWS POTENTIAL UNTIL WINDS INCREASE MID MORNING...BUT SIGNIFICANT SHEAR LOOKS MARGINAL PER NEAR UNIDIRECTIONAL WINDS AND GRADUAL INCREASE IN SPEED WITH HEIGHT. TONIGHT...THE LOW WILL DRAG A COLD FRONT INTO THE TERMINALS LATE EVENING AND OVERNIGHT. A FEW LIGHT SHOWERS OR SPRINKLES WILL BE POSSIBLE MAINLY OVER NORTHEAST IA. WINDS WILL ALSO BE DECREASING AHEAD OF THE FRONT...BUT SHOULD REMAIN GUSTY THROUGH EVENING BEFORE VEERING FROM SOUTHERLY TO WESTERLY WITH THE FRONTAL PASSAGE. && .FIRE WEATHER... ISSUED AT 406 AM CDT WED APR 16 2014 SOUTHEAST TO SOUTH WINDS WILL INCREASE TO NEAR ADVISORY CRITERIA AT TIMES LATE THIS MORNING THROUGH AFTERNOON WITH SUSTAINED SPEEDS AT 20-30 MPH AND GUSTS TO NEAR 40 MPH. MAIN QUESTION/CONCERN IS WITH SURFACE DEW POINTS AND SUBSEQUENT RELATIVE HUMIDITY VALUES. MODEL GUIDANCE SUPPORTIVE OF DEW POINTS IN THE 20S TO LOWER 30S WHICH COMBINED WITH TEMPS IN THE 50S TO LOWER 60S WOULD YIELD RELATIVE HUMIDITY VALUES MAINLY IN THE 30S. HOWEVER...DEEP MIXING AIDED BY SOUTHEAST FETCH OFF DEPARTING HIGH PRESSURE RIDGE WOULD SUPPORT SUBSTANTIALLY LOWER DEW POINTS AND RELATIVE HUMIDITY VALUES IN THE TEENS AND 20S. ALSO ADDING TO THE UNCERTAINTY IS DEGREE OF IMPACTS IF ANY OF RECENT HEAVY RAINS AND CONTINUED GREENING UP. IF THE LOWER VALUES OCCUR THEN IT WOULD LEAD TO VERY HIGH TO EXTREME GRASSLAND FIRE DANGER INDEX VALUES AND LIKELY NECESSITATE RED FLAG WARNING PORTIONS OF AREA. ENOUGH UNCERTAINTY PRECLUDES ISSUANCE OF RED FLAG WARNING AT THIS TIME... BUT WILL NEED TO MONITOR DEW POINT AND RELATIVE HUMIDITY LEVELS CAREFULLY FOR POTENTIAL OF NEEDING HEADLINE. FIRE DANGER ELEVATED TO POSSIBLY HIGH OVER DRY GRASSES AND CURED VEGETATION. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ SYNOPSIS...05 SHORT TERM...05 LONG TERM...GROSS AVIATION...05 FIRE WEATHER...05
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1006 AM CDT WED APR 16 2014 .UPDATE... ISSUED AT 1000 AM CDT WED APR 16 2014 THE FORECAST IS IN GOOD SHAPE...WITH A BAND OF SNOW IN THE FAR SOUTHEAST. THERE IS VERY STRONG MID LEVEL FGEN JUST SOUTHEAST OF THE FORECAST AREA...SO THE HEAVIEST BAND SHOULD BE IN THIS AREA. THE FAR SOUTHEAST SHOULD GET A BAND OF 2-5 INCHES THOUGH...MAINLY CONFINED TO GRANT/SOUTHEAST OTTERTAIL AND SOUTHERN WADENA COUNTIES. SO THE CURRENT WINTER WX ADVISORY HERE IS IN GOOD SHAPE. && .SHORT TERM...(TODAY THROUGH THURSDAY) ISSUED AT 331 AM CDT WED APR 16 2014 SNOW CHANCES TODAY WILL BE THE PRIMARY FORECAST HEADACHE FOR THE PERIOD. SNOW HAS STARTED TO DEVELOP ALONG A MID LEVEL FRONTOGENESIS BAND FROM NORTH CENTRAL ND DOWN TOWARDS FARGO AND FERGUS FALLS. THINK THE RAP SEEMS TO HAVE A DECENT HANDLE ON THE BAND...AND THINK THIS WILL STICK AROUND AND DROP AN INCH OR TWO BEFORE DIMINISHING AS THE SFC LOW WRAPS UP AND FRONTOGENESIS STRENGTHENS FURTHER SOUTH. FOR LATER TODAY... THE SHORTWAVE CURRENTLY MOVING INTO THE WESTERN PLAINS WILL QUICKLY PROGRESS EASTWARD INTO SOUTHERN MN. SFC LOW PRESSURE WILL MOVE FROM SOUTHERN SD TO THE IA/MN BORDER...WITH OUR SOUTHERN COUNTIES ON THE NORTHERN EDGE OF THE DEFORMATION BAND. THE GEM KEEPS MOST OF THE SNOW FURTHER TO THE SOUTH...BUT THE OTHER DETERMINISTIC MODELS STILL BRING SOME 3 TO 6 INCH AMOUNTS TO OUR SOUTHEASTERN COUNTIES. WILL CONTINUE TO KEEP THE STATUS QUO AND KEEP HIGH POPS AND THE ADVISORY GOING FOR OUR SOUTHEASTERN COUNTIES. MAIN CHANGE FOR TODAY WAS TO ADD IN A BRIEF PATCHY BLOWING SNOW MENTION FOR WHEN PRECIP IS FALLING IN OUR SOUTHEAST...AS NORTHEASTERLY WINDS WILL BE QUITE STRONG TODAY AT TIMES. THE SNOW WILL RAPIDLY TAPER OFF THIS EVENING AS THE MAIN SHORTWAVE TAKES OFF INTO WI AND HIGH PRESSURE BUILDS DOWN INTO THE NORTHERN PLAINS. SKIES WILL BEGIN TO CLEAR OUT ALTHOUGH THE WINDS WILL STAY UP AND KEEP US FROM COMPLETELY BOTTOMING OUT...WITH LOWS STAYING IN THE TEENS TO LOW 20S. SFC HIGH PRESSURE WILL CONTINUE INTO THURSDAY WITH DECREASING WINDS AND MOSTLY SUNNY SKIES. THE AIR MASS WILL STILL BE PRETTY COLD HOWEVER...SO KEPT TEMPS IN THE 30S TO AROUND 40 DEGREES. .LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY) ISSUED AT 331 AM CDT WED APR 16 2014 THURSDAY NIGHT THROUGH FRIDAY NIGHT...NORTHWESTERLY FLOW ALOFT BEGINS TO SHIFT AS A RIDGE BRIEFLY BUILDS IN AHEAD OF THE NEXT SHORTWAVE MOVING INTO SASK. A TROUGH OF LOW PRESSURE DEVELOPING OVER THE NORTHERN ROCKIES WILL BEGIN TO SHIFT WINDS BACK TO THE SOUTHEAST. MODELS HAVE A WEAK REINFORCING SHORTWAVE MOVING BY THURSDAY NIGHT BUT THINK THAT ANYTHING IT PRODUCES WILL STAY TO OUR SOUTH AND WEST. FRIDAY WILL BE A BIT WARMER THAN EARLIER IN THE WEEK BUT STILL BELOW AVERAGE WITH HIGHS IN THE 40S. MODELS DIVERGE ON BRINGING THE NEXT ROUND OF PRECIP THROUGH IN THE WARM AIR ADVECTION AHEAD OF THE NEXT SHORTWAVE. THE ECMWF AND PARTICULARLY THE GEM HAVE PRECIP MOVING QUICKLY EASTWARD FRIDAY NIGHT...WHILE THE GFS AND NAM ARE MUCH SLOWER. WILL GO WITH A BIT OF A BLEND...BUT GIVEN THE WAY SATURATION HAS TAKEN ITS TIME...LEANED A BIT TOWARDS THE SLOWER SOLUTION. JUST KEPT SOME SLIGHT POPS IN THE EAST WITH NEAR 40 PERCENT IN THE WEST FOR NOW. SATURDAY THROUGH TUESDAY NIGHT...00 UTC GFS/ECMWF ARE IN FAIR AGREEMENT. ON SATURDAY...A NEGATIVELY TILTED SHORT-WAVE WILL ROTATE THROUGH THE NORTHERN PLAINS BRINGING WARM AIR ADVECTION-INDUCED PRECIP ACROSS THE FORECAST AREA. FLOW ALOFT THEREAFTER THROUGH TUESDAY BECOMES MORE ZONAL WITH A SLIGHT PROPENSITY FOR SHORT-WAVE RIDGING. SUNDAY/MONDAY LOOK DRY...BUT PRECIP CHANCES WILL INCREASE AGAIN LATE TUESDAY INTO WEDNESDAY AS A DEEP TROUGH TAKES SHAPE ACROSS THE GREAT BASIN TURNING THE FLOW ACROSS THE NATION/S MID-SECTION TO THE SOUTHWEST. WITH THE EXCEPTION OF A RAIN/SNOW MIX AT NIGHT... MAJORITY OF PRECIP SHOULD FALL AS RAIN THROUGH THE PERIOD. AFTER ONE MORE RELATIVELY COOLER DAY ON SATURDAY (HIGHS FROM THE MID 40S TO NEAR 50 DEGREES)...MID-LEVEL THERMAL RIDGE PUSHES EAST ALLOWING TEMPERATURES TO CLIMB INTO THE 50S AND 60S SUNDAY INTO EARLY NEXT WEEK. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING) ISSUED AT 700 AM CDT WED APR 16 2014 KFAR VIS HAS BEEN BOUNCING BETWEEN 1 AND 2 MILES VIS WITH THE SNOW THAT HAS BEEN MOVING THROUGH THE AREA. THAT SHOULD DECREASE WITH VIS GOING BACK TO MVFR LEVELS AS SNOW DISSIPATES. KEPT SNOW MENTION OUT OF THE NORTHERN TAF SITES AND KEPT THEM VFR THROUGHOUT THE PERIOD. KDVL...KFAR AND KBJI WILL BE MVFR OR EVEN LOWER AT TIMES WITH SNOW BANDS. NORTHEAST WINDS WILL INCREASE INTO THE 15 TO 25 KT RANGE WITH GUSTS ABOVE 25 KTS AT TIMES. WINDS WILL DECREASE AND CIGS WILL COME UP BY THIS EVENING AS THE LOW PRESSURE SYSTEM PULLS AWAY FROM THE AREA. && .HYDROLOGY... ISSUED AT 331 AM CDT WED APR 16 2014 THE COLD NIGHTS...COOL DAYTIME HIGHS AND DIMINISHING SNOW PACK ARE PUTTING A DAMPER ON ANY ADDITIONAL RUNOFF. ISSUED LAST FORECASTS FOR SABIN...DILWORTH AND GRAFTON. THE REMAINING POINTS WITH HYDROLOGIC STATEMENTS OR FLOOD STATEMENTS ARE AT OR NORTH OF GRAND FORKS. ONLY SITES STILL RISING ARE DRAYTON AND PEMBINA ON THE RED RIVER. THE SNAKE RIVER AT ALVARADO HAS POKED ABOVE MODERATE FLOOD STAGE BY A TENTH OF A FOOT OVER THE PAST 4 TO 5 HOURS...BUT HAS BEGUN TO STABILIZE AND FULLY EXPECT IT TO BEGIN FALLING SOON GIVEN UPSTREAM FLOW NEAR WARREN. STILL ANTICIPATE THE COOLER WEATHER LASTING INTO THURSDAY WITH SOME MODERATION BY LATE WEEK INTO THE WEEKEND. TODAY/S STORM SYSTEM WILL MAINLY AFFECT PORTIONS OF WEST CENTRAL MINNESOTA WITH LITTLE OR NO PRECIPITATION OVER THE NORTHERN RED RIVER VALLEY. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...WINTER WEATHER ADVISORY UNTIL 6 PM CDT THIS EVENING FOR MNZ030>032-040. && $$ UPDATE...DK SHORT TERM...JR LONG TERM...ROGERS AVIATION...JR HYDROLOGY...ROGERS
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
700 AM CDT WED APR 16 2014 .UPDATE... ISSUED AT 700 AM CDT WED APR 16 2014 TWEAKED POPS AS THE BAND THAT DROPPED ABOUT AN INCH IN FARGO BEGINS TO DECREASE IN INTENSITY AND SHOULD CONTINUE TO DISSIPATE THROUGH MID MORNING. THE BAND BROUGHT 2-3 INCHES IN PARTS OF WADENA AND OTTERTAIL COUNTIES. WILL HAVE TO WATCH THE SOUTHERN DEFORMATION BAND CLOSELY. STILL THINK THE HEAVIEST SNOW WILL BE SOUTH OF OUR COUNTIES...BUT IF THERE IS A SLIGHT SHIFT NORTH THERE COULD BE MORE THAN SIX INCHES IN OUR FAR SOUTHEASTERN COUNTIES GIVEN THE SNOW THAT HAS ALREADY FALLEN. WILL MONITOR CLOSELY. && .SHORT TERM...(TODAY THROUGH THURSDAY) ISSUED AT 331 AM CDT WED APR 16 2014 SNOW CHANCES TODAY WILL BE THE PRIMARY FORECAST HEADACHE FOR THE PERIOD. SNOW HAS STARTED TO DEVELOP ALONG A MID LEVEL FRONTOGENESIS BAND FROM NORTH CENTRAL ND DOWN TOWARDS FARGO AND FERGUS FALLS. THINK THE RAP SEEMS TO HAVE A DECENT HANDLE ON THE BAND...AND THINK THIS WILL STICK AROUND AND DROP AN INCH OR TWO BEFORE DIMINISHING AS THE SFC LOW WRAPS UP AND FRONTOGENESIS STRENGTHENS FURTHER SOUTH. FOR LATER TODAY... THE SHORTWAVE CURRENTLY MOVING INTO THE WESTERN PLAINS WILL QUICKLY PROGRESS EASTWARD INTO SOUTHERN MN. SFC LOW PRESSURE WILL MOVE FROM SOUTHERN SD TO THE IA/MN BORDER...WITH OUR SOUTHERN COUNTIES ON THE NORTHERN EDGE OF THE DEFORMATION BAND. THE GEM KEEPS MOST OF THE SNOW FURTHER TO THE SOUTH...BUT THE OTHER DETERMINISTIC MODELS STILL BRING SOME 3 TO 6 INCH AMOUNTS TO OUR SOUTHEASTERN COUNTIES. WILL CONTINUE TO KEEP THE STATUS QUO AND KEEP HIGH POPS AND THE ADVISORY GOING FOR OUR SOUTHEASTERN COUNTIES. MAIN CHANGE FOR TODAY WAS TO ADD IN A BRIEF PATCHY BLOWING SNOW MENTION FOR WHEN PRECIP IS FALLING IN OUR SOUTHEAST...AS NORTHEASTERLY WINDS WILL BE QUITE STRONG TODAY AT TIMES. THE SNOW WILL RAPIDLY TAPER OFF THIS EVENING AS THE MAIN SHORTWAVE TAKES OFF INTO WI AND HIGH PRESSURE BUILDS DOWN INTO THE NORTHERN PLAINS. SKIES WILL BEGIN TO CLEAR OUT ALTHOUGH THE WINDS WILL STAY UP AND KEEP US FROM COMPLETELY BOTTOMING OUT...WITH LOWS STAYING IN THE TEENS TO LOW 20S. SFC HIGH PRESSURE WILL CONTINUE INTO THURSDAY WITH DECREASING WINDS AND MOSTLY SUNNY SKIES. THE AIR MASS WILL STILL BE PRETTY COLD HOWEVER...SO KEPT TEMPS IN THE 30S TO AROUND 40 DEGREES. .LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY) ISSUED AT 331 AM CDT WED APR 16 2014 THURSDAY NIGHT THROUGH FRIDAY NIGHT...NORTHWESTERLY FLOW ALOFT BEGINS TO SHIFT AS A RIDGE BRIEFLY BUILDS IN AHEAD OF THE NEXT SHORTWAVE MOVING INTO SASK. A TROUGH OF LOW PRESSURE DEVELOPING OVER THE NORTHERN ROCKIES WILL BEGIN TO SHIFT WINDS BACK TO THE SOUTHEAST. MODELS HAVE A WEAK REINFORCING SHORTWAVE MOVING BY THURSDAY NIGHT BUT THINK THAT ANYTHING IT PRODUCES WILL STAY TO OUR SOUTH AND WEST. FRIDAY WILL BE A BIT WARMER THAN EARLIER IN THE WEEK BUT STILL BELOW AVERAGE WITH HIGHS IN THE 40S. MODELS DIVERGE ON BRINGING THE NEXT ROUND OF PRECIP THROUGH IN THE WARM AIR ADVECTION AHEAD OF THE NEXT SHORTWAVE. THE ECMWF AND PARTICULARLY THE GEM HAVE PRECIP MOVING QUICKLY EASTWARD FRIDAY NIGHT...WHILE THE GFS AND NAM ARE MUCH SLOWER. WILL GO WITH A BIT OF A BLEND...BUT GIVEN THE WAY SATURATION HAS TAKEN ITS TIME...LEANED A BIT TOWARDS THE SLOWER SOLUTION. JUST KEPT SOME SLIGHT POPS IN THE EAST WITH NEAR 40 PERCENT IN THE WEST FOR NOW. SATURDAY THROUGH TUESDAY NIGHT...00 UTC GFS/ECMWF ARE IN FAIR AGREEMENT. ON SATURDAY...A NEGATIVELY TILTED SHORT-WAVE WILL ROTATE THROUGH THE NORTHERN PLAINS BRINGING WARM AIR ADVECTION-INDUCED PRECIP ACROSS THE FORECAST AREA. FLOW ALOFT THEREAFTER THROUGH TUESDAY BECOMES MORE ZONAL WITH A SLIGHT PROPENSITY FOR SHORT-WAVE RIDGING. SUNDAY/MONDAY LOOK DRY...BUT PRECIP CHANCES WILL INCREASE AGAIN LATE TUESDAY INTO WEDNESDAY AS A DEEP TROUGH TAKES SHAPE ACROSS THE GREAT BASIN TURNING THE FLOW ACROSS THE NATION/S MID-SECTION TO THE SOUTHWEST. WITH THE EXCEPTION OF A RAIN/SNOW MIX AT NIGHT... MAJORITY OF PRECIP SHOULD FALL AS RAIN THROUGH THE PERIOD. AFTER ONE MORE RELATIVELY COOLER DAY ON SATURDAY (HIGHS FROM THE MID 40S TO NEAR 50 DEGREES)...MID-LEVEL THERMAL RIDGE PUSHES EAST ALLOWING TEMPERATURES TO CLIMB INTO THE 50S AND 60S SUNDAY INTO EARLY NEXT WEEK. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING) ISSUED AT 700 AM CDT WED APR 16 2014 KFAR VIS HAS BEEN BOUNCING BETWEEN 1 AND 2 MILES VIS WITH THE SNOW THAT HAS BEEN MOVING THROUGH THE AREA. THAT SHOULD DECREASE WITH VIS GOING BACK TO MVFR LEVELS AS SNOW DISSIPATES. KEPT SNOW MENTION OUT OF THE NORTHERN TAF SITES AND KEPT THEM VFR THROUGHOUT THE PERIOD. KDVL...KFAR AND KBJI WILL BE MVFR OR EVEN LOWER AT TIMES WITH SNOW BANDS. NORTHEAST WINDS WILL INCREASE INTO THE 15 TO 25 KT RANGE WITH GUSTS ABOVE 25 KTS AT TIMES. WINDS WILL DECREASE AND CIGS WILL COME UP BY THIS EVENING AS THE LOW PRESSURE SYSTEM PULLS AWAY FROM THE AREA. && .HYDROLOGY... ISSUED AT 331 AM CDT WED APR 16 2014 THE COLD NIGHTS...COOL DAYTIME HIGHS AND DIMINISHING SNOW PACK ARE PUTTING A DAMPER ON ANY ADDITIONAL RUNOFF. ISSUED LAST FORECASTS FOR SABIN...DILWORTH AND GRAFTON. THE REMAINING POINTS WITH HYDROLOGIC STATEMENTS OR FLOOD STATEMENTS ARE AT OR NORTH OF GRAND FORKS. ONLY SITES STILL RISING ARE DRAYTON AND PEMBINA ON THE RED RIVER. THE SNAKE RIVER AT ALVARADO HAS POKED ABOVE MODERATE FLOOD STAGE BY A TENTH OF A FOOT OVER THE PAST 4 TO 5 HOURS...BUT HAS BEGUN TO STABILIZE AND FULLY EXPECT IT TO BEGIN FALLING SOON GIVEN UPSTREAM FLOW NEAR WARREN. STILL ANTICIPATE THE COOLER WEATHER LASTING INTO THURSDAY WITH SOME MODERATION BY LATE WEEK INTO THE WEEKEND. TODAY/S STORM SYSTEM WILL MAINLY AFFECT PORTIONS OF WEST CENTRAL MINNESOTA WITH LITTLE OR NO PRECIPITATION OVER THE NORTHERN RED RIVER VALLEY. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...WINTER WEATHER ADVISORY UNTIL 6 PM CDT THIS EVENING FOR MNZ030>032-040. && $$ UPDATE...JR SHORT TERM...JR LONG TERM...ROGERS AVIATION...JR HYDROLOGY...ROGERS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
621 AM CDT WED APR 16 2014 .SHORT TERM...(TODAY THROUGH TONIGHT) ISSUED AT 411 AM CDT WED APR 16 2014 MAIN CONCERN DEALING WITH STRONG LOW PRESSURE AND ITS IMPACT ON THE AREA...INCLUDING ACCUMULATING SNOW ACROSS NORTHERN WI AND GUSTY WINDS ELSEWHERE. SURFACE MAP EARLY THIS MORNING HAS AN AREA OF DEEPENING LOW PRESSURE OVER SOUTHERN SD WITH A WARM FRONT EXTENDING EASTWARD THROUGH CENTRAL IA. BROAD SCALE ISENTROPIC LIFT AND STRENGTHENING MID-LEVEL FRONTOGENESIS ACROSS CENTRAL MN INTO NORTHWEST WI STARTING TO FOCUS SOME -SN ACROSS THAT AREA. ELSEWHERE ACROSS THE AREA...SKIES WERE CLOUDY WITH TEMPERATURES RANGING FROM THE UPPER 20S TO LOWER 30S. MODELS COMING INTO BETTER AGREEMENT NOW WITH HANDLING OF PRECIPITATION ACROSS THE AREA TODAY THROUGH TONIGHT. LOOKING LIKE MODELS ARE TRENDING A FARTHER NORTH PUSH WITH PRECIPITATION ACROSS NORTHERN WI...IN THE FORM OF SNOW THIS MORNING...AND RAIN MIXING WITH SNOW BY THIS AFTERNOON. HAVE CONFINED HIGHER POPS A BIT FARTHER NORTH FOR TODAY...BUT A FEW MODELS INCLUDING THE RAP AND LATEST SREF SHOWING THE POSSIBILITY OF PRECIPITATION TOTALLY PUSHING NORTH OUT OF OUR AREA THIS AFTERNOON. 16.00Z DETERMINISTIC NAM/GFS/EC ALL SHOWING PRECIPITATION HANGING MAINLY ALONG AND NORTH OF THE I-94 CORRIDOR WITH ACCUMULATING SNOW THROUGH THIS MORNING MAINLY NORTH OF HIGHWAY 29 IN NORTHERN CLARK COUNTY. CURRENT THINKING WITH RADAR TREND AND THE 00Z MODELS IN MIND IS FOR SNOW THIS MORNING ACROSS CLARK/TAYLOR WITH 1-3 INCHES THROUGH LATE MORNING MAINLY NORTH OF HIGHWAY 29. WITH THIS IN MIND...WILL HANG ONTO THE WINTER WEATHER ADVISORY FOR NOW ACROSS CLARK AND TAYLOR...BUT STARTING TO HAVE MY DOUBTS WHETHER CARRYING IT PAST 18Z GIVEN WHAT THE RAP/SREF MODELS ARE SAYING. THIS IS OBVIOUSLY A QUICKLY CHANGING SITUATION AND WILL HAVE TO BE MONITORED CLOSELY BY THE DAY SHIFT TODAY. OTHER CONCERN FOR TODAY WILL BE INCREASING/GUSTY SOUTH WINDS MAINLY ALONG AND SOUTH OF THE I-90 CORRIDOR TODAY AHEAD OF THE DEEP LOW PRESSURE SYSTEM MOVING EAST ALONG THE IA/MN BORDER THIS AFTERNOON. WILL SEE SUSTAINED WINDS OF 20-30 MPH WITH SOME GUST AROUND 40 MPH. RIGHT NOW...WINDS LOOK BORDERLINE FOR A WIND ADVISORY...BUT WILL LET THE DAYSHIFT MONITOR THIS AS WELL. OTHERWISE...TEMPERATURES ACROSS THE AREA WILL VARY FROM AROUND 40 ACROSS NORTH CENTRAL WI...TO THE 50S ALONG/SOUTH OF I-90. FOR TONIGHT...THE LOW PRESSURE AREA WILL LIFT NORTHEAST INTO NORTHERN WI WITH DEFORMATION RAIN/SNOW...CHANGING TO ALL SNOW LOOKING LIKELY ACROSS EASTERN MN INTO NORTHERN WI. LOOKS LIKE THE SOUTHERN PERIPHERY OF OF THE DEFORMATION SNOW CLIPS CLARK AND TAYLOR WITH ACCUMULATING SNOW AGAIN TONIGHT...WITH AMOUNTS OF 1-2 INCHES. MEANWHILE...THERE ARE A FEW WRF MODELS SHOWING A BAND OF SHOWERS FORMING ALONG THE COLD FRONT OF THE LOW SWINGING ACROSS SOUTHERN PARTS OF THE AREA DURING THIS EVENING. PUSHED POPS INTO LIKELY CATEGORY BASED ON THIS SIGNAL. APPEARS PRECIPITATION MIXES AND CHANGES TO ALL SNOW THROUGH THE NIGHT ACROSS THE REST OF THE AREA WITH THE BULK OF THE PRECIPITATION LIFTING NORTHEAST OF I-94 BY MORNING. THEREFORE...LITTLE IF ANY SNOW ACCUMULATION EXPECTED SOUTHWEST OF I-94 THROUGH THE NIGHT. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 411 AM CDT WED APR 16 2014 THERE MAY BE SOME LINGERING LIGHT SNOW WITH MINIMAL ACCUMULATION THURSDAY MORNING NORTHEAST OF I-94. REST OF THE DAY WILL BE MOSTLY CLOUDY...AND COOL WITH HIGHS ONLY MAKING IT INTO THE 40 TO 50 DEGREE RANGE. A COLD NIGHT THEN SETS UP THURSDAY NIGHT AS HIGH PRESSURE NOSES INTO THE AREA WITH LOWS DROPPING OFF INTO THE 20S. A MID-LEVEL SHORTWAVE TROUGH/PV-ADVECTION ROTATES THROUGH SOUTHERN MN/IA ON FRIDAY. THIS GIVES PORTIONS OF NORTHEAST IA/SOUTHEAST MN A SLIGHT CHANCE OF EARLY MORNING LIGHT SNOW AND DAYTIME RAIN. OTHERWISE...PLAN ON HIGHS IN THE AGAIN IN THE 40S TO A FEW LOWER 50S ACROSS FAR NORTHEAST IA/SOUTHWEST WI. A CHANCE OF RAIN ENTERS THE PICTURE FOR SATURDAY AFTERNOON THROUGH SUNDAY NIGHT AS A MID-LEVEL TROUGH AND WEAK SURFACE COLD FRONT PUSH SLOWLY EAST ACROSS THE AREA. LOOK FOR HIGHS SATURDAY AND SUNDAY IN THE 50S. THERE MAY BE A FEW LINGERING SHOWER ACROSS CENTRAL WI ON MONDAY BUT THE REST OF THE AREA WILL SEE MOSTLY SUNNY SKIES AS MID/UPPER LEVEL RIDGE BUILDS INTO THE AREA. THIS WARMS HIGHS INTO THE UPPER 50S TO THE LOWER 60S. LOOK FOR THIS RIDGE TO PERSIST INTO TUESDAY FOR MOSTLY SUNNY CONDITIONS AND HIGHS TOPPING OFF AGAIN IN THE UPPER 50S TO LOWER 60S...OR RIGHT AROUND NORMAL LEVELS. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING) ISSUED AT 621 AM CDT WED APR 16 2014 WITH THE AREA OF LOW PRESSURE OVER SOUTH DAKOTA...THE WINDS AT KLSE HAVE YET TO RESPOND TO THE TIGHTENING GRADIENT AND ARE STILL AROUND 10 KNOTS. THIS SUGGESTS THERE IS THE POSSIBILITY OF SOME LOW LEVEL WIND SHEAR FOR A FEW HOURS THIS MORNING. CONFIDENCE IS NOT HIGH IN THIS AS THE 16.06Z NAM AND 16.09Z RAP WINDS ALOFT APPEAR TO BE STRONG COMPARED TO THE LOCAL VWP WINDS...BUT WILL INCLUDE IT AS OTHER RADAR VWP WINDS ARE SHOWING THE STRONGER WINDS. THIS SHOULD END BY MID MORNING AS THE SURFACE WINDS INCREASE AND WITH THE WINDS ALOFT FORECAST TO DECREASE AS THE LOW LEVEL JET WEAKENS. ONCE THE DEEPER MIXING DEVELOPS THIS MORNING...EXPECT TO SEE GUSTS AT BOTH SITES OUT OF THE SOUTHEAST WITH KRST AROUND 30 KNOTS. THESE WINDS SHOULD SETTLE DOWN SOME TOWARD EVENING AS THE MIXING DECREASES. AS THE LOW MOVES INTO NORTHWEST WISCONSIN...SOME LIGHT RAIN WILL BE POSSIBLE LATE THIS AFTERNOON INTO THE EVENING WITH NO VISIBILITY RESTRICTIONS EXPECTED. AS THE COLD FRONT APPROACHES...THE CEILINGS SHOULD COME DOWN TO MVFR AND THERE IS THE POSSIBILITY THAT THERE COULD BE A PERIOD OF SOME MVFR VISIBILITIES AT KRST IN THE RAIN...BUT CONFIDENCE NOT HIGH IN THIS. THE COLD FRONT SHOULD GO THROUGH OVERNIGHT SWINGING THE WINDS AROUND TO THE NORTHWEST WITH THE CEILINGS REMAINING MVFR. && .HYDROLOGY... ISSUED AT 411 AM CDT WED APR 16 2014 RIVERS REMAIN AT ELEVATED LEVELS FROM HEAVIER RAINFALL THIS PAST WEEKEND. FLOOD WARNINGS REMAIN IN EFFECT FOR THE SOUTHERN REACHES OF THE KICKAPOO RIVER AT GAYS MILLS AND STEUBEN. A FLOOD WARNING IS ALSO IN EFFECT FOR THE MISSISSIPPI AT WABASHA AND MCGREGOR. SEE WWW.WEATHER.GOV/AHPS2/INDEX.PHP?WFO=ARX FOR LATEST RIVER LEVELS AND FORECASTS. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...WINTER WEATHER ADVISORY UNTIL 7 AM CDT THURSDAY FOR WIZ017-029. MN...NONE. IA...NONE. && $$ SHORT TERM...DAS LONG TERM...DAS AVIATION...04 HYDROLOGY...DAS
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
1059 AM PDT WED APR 16 2014 .SYNOPSIS...DRY CONDITIONS WILL CONTINUE THROUGH THE WEEKEND. PATCHY FOG AND CLOUDS NEAR THE COAST WILL BECOME MORE EXTENSIVE THURSDAY NIGHT AND FRIDAY AS A WEAK WEATHER SYSTEM MOVES ONSHORE. A STRONGER LOW PRESSURE SYSTEM WILL ARRIVE LATE MONDAY AND TUESDAY BRINGING A THREAT FOR SHOWERS...COLDER TEMPERATURES...AND GUSTY WINDS. && .DISCUSSION...AS OF 8:30 AM PDT WEDNESDAY...MINOR FORECAST UPDATE THIS MORNING WITH CLOUDS MOSTLY CONFINED AROUND MONTEREY BAY AND THROUGH THE SALINAS VALLEY. THE REASON? NORTHERLY SURFACE GRADIENT RAMPED UP TO OVER 7 MB OVERNIGHT HELPING TO PUSH THE STRATUS DECK TO THE SOUTH. MOSTLY SUNNY CONDITIONS ARE FORECAST FOR ALL AREA BY LATER THIS MORNING WITH WARM CONDITIONS INLAND -- UPPER 70S TO AROUND 90. AT THE COAST AN WEAK ONSHORE FLOW WILL CONTINUE WHICH WILL KEEP IT CLOSER TO THE 60S AND LOWER 70S. ONE EXCEPTION WILL BE FOR PARTS OF SANTA CRUZ WHERE THE NORTHERLY FLOW WILL DOWNSLOPE AND HELP TO PUSH HIGHS 75-80. QUIET WEATHER WILL CONTINUE THROUGH THE REST OF THE WEEK INTO MONDAY BEFORE A BIG CHANGE HITS US ON TUESDAY. GOOD MODEL AGREEMENT THAT A COLD SYSTEM WILL DROP DOWN TO OUR AREA HELPING TO DROP 700 MB TEMPS TO THE -9 TO -11C RANGE. MOISTURE AVAILABILITY IS THE ONE BIG QUESTION MARK, ALTHOUGH SOME SHOWERS SHOULD BE GENERATED. IF THE MODELS VERIFY SNOW LEVELS WILL DROP TO UNDER 4000 FEET AND INSTABILITY WILL GREATLY INCREASE LEADING TO SOME THUNDERSTORMS AS WELL. WINDS WILL ALSO BECOME GUSTY FROM THE NORTH. UNLESS THERE IS A HUGE CHANGE IN THE MODELS, TEMPS WILL BE LOWERED FOR TUESDAY INTO WEDNESDAY ESPECIALLY FOR THE HILLS. STILL NEARLY A WEEK OUT, BUT IT`S VERY INTERESTING FOR A LATE APRIL SYSTEM! .PREVIOUS DISCUSSION...TONIGHTS VIIRS SATELLITE IMAGERY AROUND 230 AM SHOWED PATCHY LOW CLOUDS NEAR MONTEREY BAY AND SALINAS VALLEY. LATEST GOES FOG PRODUCT IMAGERY INDICATING STRATUS HAS BECOME A LITTLE MORE WIDESPREAD IN THE SALINAS VALLEY...NEAR HALF MOON BAY...AND MONTEREY BAY THE LAST COUPLE HOURS. BREEZY NORTHWEST WINDS OVER THE OPEN WATERS HAVE KEPT THE BOUNDARY LAYER WELL MIXED AND CONFINED STRATUS TO CONVERGENCE AND UPSLOPE AREAS NEAR THE COAST FAVORED BY NW WINDS. SHORT WAVE RIDGE WILL PROGRESS EASTWARD ACROSS THE STATE TODAY...KEEPING THE MARINE LAYER UNDER 1500 FEET. SURFACE PRESSURE GRADIENTS WILL REMAIN STRONG FROM THE NORTHWEST TO SOUTHEAST WITH SFO-ACV OVER 6 MB TODAY AND WINDS WILL REMAIN AT LEAST BREEZY OVER THE OPEN WATERS. HRRR MODEL SURFACE RH FIELD INDICATES LIMITED STRATUS AGAIN TODAY. AS THE RIDGE SHIFTS EASTWARD THE FLOW WILL BECOME MORE ONSHORE THURSDAY WITH A BETTER ESTABLISHED MARINE LAYER...SO EXPECT EXTENSIVE STRATUS TO RETURN TO COASTAL AREAS BY THURSDAY MORNING. A WEAK TROF IN ZONAL FLOW WILL APPROACH THE COAST THURSDAY NIGHT DEEPENING THE MARINE LAYER AND INCREASING ONSHORE FLOW. THIS TROF SPLITS OVER THE AREA FRIDAY...AND THE LACK OF UPPER LEVEL LIFT SHOULD KEEP CONDITIONS DRY. COOLER AIR ALOFT WITH 850 MB TEMPERATURES DROPPING TO 10 DEG C SHOULD DISRUPT THE MARINE LAYER FRIDAY BUT SPREAD COOLER AIR INLAND WITH CONTINUED ONSHORE FLOW. AFTER A BRIEF BREAK SATURDAY UNDER WEAK HIGH PRESSURE AND MOSTLY CLEAR SKIES...ANOTHER MINOR SYSTEM WILL BRUSH BY TO THE NORTH OF OUR AREA SUNDAY WITH MORE COASTAL CLOUDS. A STRONGER TROF WILL DROP OVER CALIFORNIA LATE MONDAY AND TUESDAY BRINGING A THREAT FOR SHOWERS AND MUCH COOLER CONDITIONS WITH GUSTY WINDS. FORECAST MODELS ARE CONSISTENTLY ADVERTISING THIS STRONGER SYSTEM...AND EVEN THOUGH THE SYSTEM LACKS A SIGNIFICANT MOISTURE TAP...COLD AIR ALOFT WILL BE PLENTIFUL AND SHOWERS ARE CERTAINLY POSSIBLE ESPECIALLY OVER THE MOUNTAINS. && .AVIATION...AS OF 11:00 AM PDT WEDNESDAY...A STRONG NORTH TO SOUTH SURFACE PRESSURE GRADIENT HAS HELPED TO CLEAR OUT THE STRATUS CLOUDS THIS MORNING AND HAS ALSO HELPED TO DRY THE ATMOSPHERE OUT WITH DEW POINTS RUNNING ABOUT 2 DEGREES COOLER AND TEMPERATURES 5 DEGREES WARMER OVER YESTERDAY. THE CURRENT VISIBLE SATELLITE IMAGE IS SHOWING CLEAR SKIES AROUND THE FORECAST AREA INCLUDING OVER THE COASTAL WATERS. THIS DRYING AIRMASS WILL HELP TO SLOW THE RETURN OF STRATUS TO THE FORECAST AREA TONIGHT. VICINITY OF KSFO...VFR. WINDS WILL INCREASE OUT OF THE WEST THIS AFTERNOON WITH THE SEA BREEZE EXPECTED TO REACH 20 KT. KSFO BRIDGE APPROACH...SIMILAR TO KSFO. MONTEREY BAY AREA TERMINALS...VFR THROUGH LATE EVENING. WINDS WILL INCREASE OUT OF THE WEST TO 10 TO 15 KT WITH THE AFTERNOON SEA BREEZE. && .MARINE...AS OF 11:00 AM PDT WEDNESDAY...A STRONG NORTH TO SOUTH SURFACE PRESSURE GRADIENT IS RESULTING IN MODERATE TO STRONG WINDS ALONG THE COAST THIS MORNING. GALE FORCE WINDS ARE EXPECTED ALONG THE NORTHERN OUTER COASTAL WATERS THROUGH THIS EVENING. LOCALLY STRONG WINDS ARE POSSIBLE DOWNWIND OF COASTAL POINTS SUCH AS PT SUR. MODERATE TO STRONG WINDS ARE ANTICIPATED TO PERSIST INTO THE WEEKEND. THE PROLONGED PERIOD OF STEADY WIND WILL RESULT IN LARGE STEEP SEAS EVEN OUTSIDE OF THE AREAS OF STRONGEST WINDS. && .MTR WATCHES/WARNINGS/ADVISORIES... .TDAY...SCA...PIGEON PT TO PT PINOS 0-10 NM GLW...PT ARENA TO PT REYES 10-60 NM GLW...PT REYES TO PIGEON PT 10-60 NM SCA...PT ARENA TO PT REYES 0-10 NM SCA...PT REYES TO PIGEON PT 0-10 NM SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM SCA...PT PINOS TO PT PIEDRAS BLANCAS 10-60 NM GLW...PIGEON PT TO PT PINOS 10-60 NM SCA...MONTEREY BAY FROM 1 PM && $$ PUBLIC FORECAST: BELL/KBB AVIATION: LARRY MARINE: LARRY VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO FOLLOW US ON FACEBOOK, TWITTER, AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.SANFRANCISCOBAYAREA.GOV WWW.TWITTER.COM/NWSBAYAREA WWW.YOUTUBE.COM/NWSBAYAREA
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
350 PM MDT WED APR 16 2014 .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 350 PM MDT WED APR 16 2014 SHORTWAVE TROUGH CURRENTLY MOVING ACROSS COLORADO. MOISTURE AND WEAK ASCENT BEGINNING TO INCREASE AGAIN...THOUGH BEST ASCENT OVER SOUTHWEST COLORADO. SOME SHOWERS ONGOING SOUTH OF THE PALMER DIVIDE...BEGINNING TO CREEP NORTHWARD. AIRMASS SLIGHTLY UNSTABLE WITH CAPES AROUND 100 J/KG ACROSS SOUTHERN MOUNTAINS...SOUTHERN FOOTHILLS AND PARK COUNTY. WINDS HAVE BEGUN TO DECREASE ACROSS THE PLAINS...BECOMING A BIT MORE EASTERLY. TROUGH STILL EXPECTED TO MOVE EAST ACROSS COLORADO TONIGHT. MOISTURE TO CONTINUE TO SPREAD NORTHWARD OVER THE AREA. THOUGH THE MAIN BATCH OF MID LEVEL ASCENT EXPECTED TO SLIDE ACROSS SOUTHERN COLORADO...THERE WILL BE ENOUGH ASCENT OVER THE AREA FOR AT LEAST A SLIGHT CHANCE OF SHOWERS. BEST CHANCE FOR SHOWERS STILL LOOKS TO BE ACROSS THE MOUNTAINS AND FOOTHILLS SOUTH OF INTERSTATE 70 AND ALONG THE PALMER DIVIDE. LATEST MODELS CONTINUE TO GENERATE THE BULK OF THE QPF SOUTH OF THE CFWA. BUT LOW LEVEL EAST SOUTHEAST FLOW WILL HELP WITH LOCAL UPSLOPE ACROSS SOUTH PARK AND SOUTHERN FOOTHILLS. LATEST RAP SHOWS LIGHT QPF IN THIS AREA AND EXTENDING INTO THE CENTRAL MOUNTAINS. WILL KEEP THE HIGHER POPS IN THIS AREA WITH LIGHT ACCUMULATIONS. LOWER POPS FURTHER NORTH WITH WEAK MID LEVEL ASCENT. SYSTEM PULLS AWAY OVERNIGHT WITH FLOW ALOFT BECOMING NORTHWEST. DRIER AND MORE SUBSIDENT AIRMASS SPREADS INTO AREA. THREAT FOR PRECIPITATION TO DECREASE AFTER MIDNIGHT AND SHOULD COME TO AN END TOWARDS MORNING. MAY BE A FEW LINGERING FLURRIES OR LIGHT SNOW ACROSS LINCOLN COUNTY. ON THURSDAY...NORTHWEST FLOW TO PREVAIL OVER THE AREA AS UPPER TROUGH MOVES INTO THE NORTHERN AND CENTRAL PLAINS STATES. UPPER RIDGE TO BUILD ACROSS THE GREAT BASIN...AND WILL SPREAD WARMER AIR INTO THE AREA. MODELS SHOW SOME WRAP AROUND MOISTURE MOVING INTO THE PLAINS DURING THE AFTERNOON. LATEST NAM AND GFS GENERATE SOME LIGHT SHOWERS FAR NORTHEAST CORNER. AIRMASS LOOKS FAIRLY SUBSIDENT...WILL NOT INCLUDE ANY SHOWERS AT THIS POINT. TEMPERATURE AND THICKNESS PROGS SHOW HIGHS WARMING INTO THE LOWER 60S ACROSS THE PLAINS. .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 303 PM MDT WED APR 16 2014 THE MAIN FEATURE FOR THIS FORECAST WILL BE A WEAK...SLOW MOVING UPPER TROUGH MOVING OUT OF THE DESERT SOUTHWEST FROM FRIDAY AFTERNOON THROUGH SUNDAY. AHEAD OF THE TROUGH...A WARM UPPER RIDGE WILL BE OVER THE STATE FRIDAY AFTERNOON WITH WARM TEMPERATURES NA MAINLY DRY CONDITIONS ACROSS THE FORECAST AREA. THERE MAY BE A FEW AFTERNOON SHOWERS OVER THE MOUNTAINS...BUT THE MAIN MOISTURE FROM THE SOUTHWEST U.S. UPPER TROUGH IS NOT EXPECTED TO ARRIVE UNTIL LATER ON SATURDAY. BY SATURDAY AFTERNOON...AS THE BROAD UPPER TROUGH APPROACHES THE STATE...SHOWERS WILL BE MORE WIDESPREAD ON SATURDAY AND SUNDAY AFTERNOONS. THE AIRMASS SHOULD REMAIN WARM ENOUGH THAT CONVECTIVE ACTIVITY WILL CONTAIN SOME THUNDERSTORMS. BOTH DAYS WILL BE FAIRLY SIMILAR AS THE TROUGH SLOWLY PROGRESSES ACROSS THE STATE. AFTERNOON CONVECTION ON SATURDAY AND SUNDAY HAS A FAIR CHANCE OF EXTENDING WELL OUT ONTO THE PLAINS EACH AFTERNOON DUE TO THE BROAD NATURE OF THE UPPER TROUGH. THE FIRST HALF OF NEXT WEEK WILL THEN BE WARMER AND DRIER AS STRONG UPPER RIDGING DEVELOPS OVER THE DESERT SOUTHWEST. ALL MODELS ARE IN PRETTY GOOD AGREEMENT THROUGH NEXT WEEK WITH THE GENERAL TIMING OF THE MOVEMENT OF THE SOUTHWEST U.S. TROUGH AND THEN DEVELOPMENT OF THE STRONG UPPER RIDGING. TEMPERATURES SHOULD BE WELL ABOVE NORMAL FOR THE MONDAY THROUGH WEDNESDAY TIMEFRAME. && .AVIATION...(FOR THE TAFS THROUGH 06Z THURSDAY EVENING) ISSUED AT 350 PM MDT WED APR 16 2014 NORTHEASTERLY WINDS ONGOING ACROSS AREA AIRPORTS...STILL EXPECTED TO WEAKEN THIS EVENING AND SHIFT CLOCKWISE TO THE SOUTHEAST. MOISTURE TO CONTINUE TO INCREASE FROM THE SOUTH...WITH CEILINGS LOWERING TO AROUND 8000 FEET AGL. SLIGHT CHANCE OF SHOWERS THROUGH THIS EVENING THROUGH AROUND 10Z...BETTER CHANCE AT KAPA...WITH PERHAPS CEILINGS AS LOW AS 5000 FEET AGL AT KAPA AND KBJC. VCSH STILL SEEMS REASONABLE AT THIS TIME. WINDS TO BE BECOME SOUTHERLY OVERNIGHT WITH IMPROVING CONDITIONS AS THE SYSTEM MOVES AWAY FROM THE AREA. WINDS TO REMAIN SOUTHERLY THURSDAY...MAY BE A BIT MORE SOUTHEAST AT KDEN AND KAPA DURING THE AFTERNOON. VFR TO CONTINUE. && .BOU WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...D-L LONG TERM...DANKERS AVIATION...D-L
AREA FORECAST DISCUSSION
NWS PUEBLO CO
325 PM MDT WED APR 16 2014 .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 254 PM MDT WED APR 16 2014 ...HEAVY WET SNOW FOR THE SOUTHEASTERN MOUNTAINS TONIGHT... RAPIDLY EVOLVING STORM SYSTEM NOW IS MOVING INTO WRN CO THIS AFTERNOON. ALREADY AM SEEING SOME BANDED PRECIP...IN THE FORM OF SHRA...DEVELOP OVER EL PASO COUNTY. DEWPOINTS STILL PRETTY LOW OVER THE PLAINS...WHICH WILL HELP COOL THINGS OFF THIS EVE AS WET BULB IS REACHED IN HEAVIER PRECIP. EXPECT PRECIP TO EXPAND AND INTENSIFY THROUGH THE AFTERNOON...REACHING ITS PEAK FROM 00Z THROUGH 06Z TONIGHT. A COUPLE OF RECENT TRENDS ARE MAKING FOR A RATHER TRICKY FORECAST FOR THE SHORT TERM. RECENT GUIDANCE IS CONSIDERABLY WARMER THAN IT HAD BEEN A COUPLE DAYS AGO...WITH H7 TEMPS ONLY FALLING TO MINUS 5 OR 6 AS OPPOSED TO THE MINUS 10 OR LOWER FROM EARLIER MODEL RUNS. THIS IS POINTING AT THE SNOW LEVELS GENERALLY STAYING AT OR ABOVE 6000 FEET TONIGHT. BUT DEPENDING ON EVENTUAL STRENGTH AND TIMING...WOULD NOT BE SURPRISED TO SEE SNOW FALLING AT THE LOWER ELEVATIONS. JUST NOT EXPECTING MUCH IF ANY ACCUMULATION BELOW 6K FEET...EXCEPT MAYBE ON GRASSY SURFACES. THE WINTER WX ADVISORY FOR THE SRN I-25 CORRIDOR WILL BE A PARTICULAR CHALLENGE SINCE ELEVATIONS FROM WALSENBURG TO TRINIDAD ARE GENERALLY IN THE 6000- 6500 FOOT RANGE. SO...EVEN A SLIGHT SHIFT IN THE LOW LEVEL TEMPERATURES THIS EVE COULD MAKE THE DIFFERENCE BETWEEN WET PAVEMENT AND A FEW INCHES OF SLUSH. HAVE GENERALLY PLAYED THE MIDDLE ROAD OF MODEL CONSENSUS...WHICH HAS SNOW LEVELS AT OR ABOVE THAT ELEVATION FOR THE EARLY EVE. BUT...HIGHER TRRN TO THE WEST AND CLOSER TO SPANISH PEAKS COULD SEE SIGNIFICANT WET SNOW...MORE THAN SIX INCHES FOR SOME AREAS. OTHER ISSUE IS THE RECENT TREND TOWARDS THE HEAVIEST ACCUMS FALLING OVER THE SRN ZONES...THE WETS AND SRN SANGRES GENERALLY SOUTH OF HIGHWAY 50. THE HRRR AND LOCAL HI-RES WRF...FOR EXAMPLE...KEEP MOST OF THE HEAVY PRECIP SOUTH OF THE PIKES PK REGION. THE NAM AND RUC..LOWER RES...KEEP HEAVY PRECIP OVER THE PIKES PEAK REGION. GIVEN THE POOR PERFORMANCE OF THE HIGHER RES SOLUTIONS SO FAR...AM INCLINED TO KEEP WITH AT LEAST MODERATE ACCUMS FOR PIKES PEAK...ALTHOUGH IT SEEMS REASONABLE THAT SRN AND ERN SIDES WILL GET A BIT MORE THIS EVE. MODELS ARE HITTING THE SRN SANGRES AND HIGHER WETS PRETTY HARD THROUGH 06-08Z TONIGHT. HAVE CONSIDERED UPGRADING FOR THOSE ZONES...BUT SINCE THE LIQUID-SNOW RATIOS WILL BE HIGHER GIVEN THE WARMER LOW-LEVEL THERMAL PROFILE...EXPECT THE MORE SIGNIFICANT ACCUMS TO BE PRETTY HIGH UP AND SPOTTY. SO...ADVISORIES LOOK GOOD FOR NOW BUT WILL HAVE TO FOLLOW THE SHORT TERM TRENDS PRETTY CAREFULLY. WILL SEE THE SYSTEM CLEAR OUT GRADUALLY FROM N TO S AFTER MIDNIGHT. COULD EVEN SEE SOME CLEARING BY SUNRISE ON THURSDAY. BALANCE OF THURSDAY LOOKS PRETTY NICE...WITH TEMPS REBOUNDING TO THE UPPER 50S OVER THE PLAINS BY AFTERNOON...AND INCREASING AMOUNTS OF SUN. ROSE .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 254 PM MDT WED APR 16 2014 NEXT SYSTEM WILL BE MOVING INTO THE REGION OVER THE WEEKEND BRINGING A RETURN OF ACTIVE WEATHER IN THE EXTENDED. CLOSED LOW MOVES IN FROM THE PACIFIC...ACROSS SOUTHERN CA AND INTO THE DESERT SOUTHWEST THROUGH FRIDAY NIGHT. MOISTURE INCREASES...PARTICULARLY ACROSS WESTERN AREAS ON FRIDAY...SO SHOULD SEE ISOLATED TO SCATTERED RAIN AND HIGHER ELEVATION SNOW SHOWERS OVER THE MOUNTAINS WITH SOME ISOLATED EMBEDDED THUNDERSTORMS POSSIBLE DURING THE AFTERNOON. ANY SNOWFALL ACCUMULATIONS LOOKS LIGHT THROUGH THIS PERIOD...AND CONFINED TO THE HIGHER ELEVATIONS. THIS SYSTEM WILL GRADUALLY FILL AS IT MOVES INTO THE FOUR CORNERS REGION ON SATURDAY THEN ACROSS CO THROUGH SUNDAY MORNING AS AN OPEN TROF. PRECIPITATION WILL INCREASE ACROSS THE SOUTHWEST MOUNTAINS FRIDAY NIGHT...THEN SPREAD ACROSS ALL OF THE MOUNTAINS AND ADJACENT PLAINS ON SATURDAY. WITH COOLING ALOFT...LAPSE RATES STEEPEN...AND A COLD FRONT...THOUGH IT IS NOT ALL THAT COOL BEHIND IT...WILL MOVE THROUGH THE SOUTHEAST PLAINS DURING THE AFTERNOON. NAM12 IS THE FARTHEST SOUTH WITH THE FRONT SAT AFTERNOON SHOWING EASTERLY WINDS ACROSS THE PLAINS AND DEW POINTS INCREASING INTO THE 40S TO AROUND 50 NEAR THE EASTERN BORDER BY 00Z. GFS IS A TAD SLOWER...WITH NORTHERLY WINDS DROPPING THROUGH THE I-25 CORRIDOR DURING THE AFTERNOON...AND DEW POINTS IN THE 30S THROUGH THE AFTERNOON. ECMWF IS FAIRLY SIMILAR TO THE GFS...THOUGH A JUST A TAD MOISTER. EITHER WAY...SNOW LEVELS WILL BE ON THE HIGH SIDE AGAIN...PROBABLY AROUND 9.5-10KFT...SO BELOW THIS ELEVATION WILL HAVE TO MONITOR THE BURN SCARS CLOSELY FOR RAINFALL...ESPECIALLY THE WALDO. FOR NOW THOUGH...THINK THAT GFS PROBABLY HAS THE BEST HANDLE...AND ANY LOCALLY HEAVIER PRECIPITATION AMOUNTS WILL BE SPOTTY AS MODEL CAPE VALUES ARE NOT ALL THAT HIGH. ISOLATED THUNDERSTORMS WILL ALSO SPREAD ACROSS THE SOUTHEAST PLAINS SATURDAY AFTERNOON AND EVENING...THOUGH RAINFALL AMOUNTS LOOK FAIRLY LIGHT AT THIS POINT AS HIGHER CAPE REMAINS WELL TO THE EAST. THIS SYSTEM SLOWLY EXITS EASTERN CO ON SUNDAY...SO AFTER PRECIPITATION WINDS DOWN OVERNIGHT...ENOUGH INSTABILITY AND RESIDUAL MOISTURE WILL BE PRESENT FOR ANOTHER ROUND OF ISOLATED THUNDERSTORMS SUNDAY AFTERNOON. THESE LOOK A LITTLE SPOTTIER IN COVERAGE. DRY WEATHER RETURNS FOR EARLY NEXT WEEK...THEN THE FORECAST WILL REVOLVE AROUND TRACK OF THE NEXT UPPER LOW WHICH DROPS INTO THE GREAT BASIN...THEN EVENTUALLY LIFTS OUT TO THE NORTH OF THE FORECAST AREA WED. THIS WILL PUT MOST OF SOUTH CENTRAL AND SOUTHEAST COLORADO UNDER STRONG SOUTHWEST FLOW ALOFT WITH THE POTENTIAL FOR CRITICAL FIRE WEATHER CONDITIONS DEVELOPING ESPECIALLY BY WEDNESDAY. DEPENDING ON THE CONDITIONS OF FUELS...MAY NEED SOME FIRE WEATHER HIGHLIGHTS FOR THIS DAY. OTHERWISE...DRY LINE WILL BE LURKING NEAR THE CO/KS BORDER DURING THE EARLY TO MIDDLE PART OF NEXT WEEK. TRENDS IN THE LATEST OPERATIONAL GFS AND ECWMF...SEEM TO SUGGEST A MORE NORTHERN TRACK AND LESS OF A PERSISTENT MERIDIONAL FLOW EARLY NEXT WEEK...SO THESE LATEST RUNS KEEP THE DRYLINE JUST TO OUR EAST. HOWEVER...THERE ARE STILL SOME RATHER LARGE DIFFERENCES IN THE EXTENDED MODELS FOR WED AS GFS SHOWS MORE ENERGY DROPPING SOUTHWARD INTO THE BASE OF THE TROF ACROSS THE GREAT BASIN WHICH EC DOES NOT HAVE...SO JURY IS STILL OUT. EITHER WAY...SHOULD BE AN ACTIVE PERIOD THROUGH NEXT WEEK. -KT && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 254 PM MDT WED APR 16 2014 EXPECT PRECIP TO EXPAND IN COVERAGE AND INTENSITY THROUGH THIS EVE. KCOS WILL BE ON THE NRN SIDE OF THE HEAVIER BANDS OF PRECIP...BUT THERE IS A GOOD CHANCE IT WILL GO DOWN TO IFR CIGS AND/OR VIS FOR THE 00-06Z TIME FRAME. KPUB WILL FOLLOW SUIT...ABOUT AN HOUR OR SO LATER AS PRECIP SLOWLY SHIFTS TO THE SOUTH. SNOW LEVELS CONTINUE TO LOOK TO BE AROUND 5500-6000 FEET FOR MOST OF THE AREA. KALS COULD SEE SOME SPOTTY PRECIP TONIGHT...BUT THE GREATER IMPACT WILL BE ALONG AND E OF THE SANGRES...WETS...AND PIKES PEAK. CLEARING CONDITIONS THU MORNING COULD LEAD TO SOME BRIEF FG OR BR FOR ANY AREAS THAT SEE PRECIP EARLY ON. ROSE && .PUB WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO 4 AM MDT THURSDAY FOR COZ072>075-079>082-087-088. && $$ SHORT TERM...ROSE LONG TERM...KT AVIATION...ROSE
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1058 AM MDT WED APR 16 2014 .UPDATE... ISSUED AT 1057 AM MDT WED APR 16 2014 SURFACE FRONT HAS PUSHED SOUTH ACROSS THE PLAINS WITH WEAK UPPER TROUGH NOW OVER NEBRASKA. WINDS BRIEFLY WENT NORTHEAST WITH THE FRONT PASSAGE...BUT NOW TRENDING MORE NORTHWESTERLY. WINDS A BIT GUSTY ALONG FOOTHILLS AND FAR NORTHEAST PLAINS AS WELL AS ALONG THE HIGHER MOUNTAIN PASSES. MOUNTAIN SNOW HAS DECREASED CONSIDERABLY AS SUBSIDENCE SPREADS INTO THE REGION BEHIND THE TROUGH. WEB CAMS STILL INDICATING A FEW SNOW SHOWERS ALONG THE CONTINENTAL DIVIDE OF SUMMIT AND GRAND COUNTIES. MAY ALSO BE SOME SHOWERS OVER THE PARK AND GORE RANGES OF WESTERN JACKSON COUNTY. AIRMASS COOLER BEHIND THE TROUGH AND SURFACE FRONT. NEXT SYSTEM MOVES INTO SOUTHWEST COLORADO THIS EVENING. MOISTURE AND WEAK LIFT SPREADS INTO MOUNTAINS AND FOOTHILLS DURING THE AFTERNOON. BEST CHANCE FOR ANY SHOWERS THIS AFTERNOON TO BE IN THE HIGH COUNTRY SOUTH OF INTERSTATE 70 AND WILL ADJUST POPS AND WEATHER ACCORDINGLY. WILL ALSO BACK OFF ON THE WEATHER ACROSS THE PLAINS UNTIL AFTER 21Z WHEN MID LEVEL ASCENT BEGINS TO INCREASE. LATEST MODELS SHOWING A BIT OF CAPE THIS AFTERNOON AND EVENING. ENOUGH FOR SHOWERY PRECIPITATION BUT NOT ENOUGH TO MENTION THUNDER. SYSTEM TO MOVE ACROSS SOUTHERN COLORADO THIS EVENING AND OVERNIGHT. BEST CHANCE FOR ANY ACCUMULATING SNOW STILL LOOKS TO BE ACROSS SOUTHERN MOUNTAINS...SOUTHERN FOOTHILLS...PARK COUNTY AND PALMER DIVIDE WITH PERHAPS AN INCH OR TWO OF ACCUMULATION. WILL KEEP THE LOW POPS FOR THE DENVER AREA NORTHWARD TONIGHT AS THERE APPEARS TO BE ENOUGH MID LEVEL ASCENT AND MOISTURE TO GENERATE A FEW SNOW SHOWERS. TEMPERATURES TO BE WARM ENOUGH FOR MAINLY RAIN DURING THE EVENING. NO SNOW ACCUMULATION EXPECTED OVERNIGHT. CURRENT GRIDS FOR THIS EVENING AND OVERNIGHT SEEM REASONABLE AT THIS TIME. && .SHORT TERM...(TODAY THROUGH TONIGHT ) ISSUED AT 333 AM MDT WED APR 16 2014 COLD FRONT ASSOCIATED WITH THE PASSAGE OF AN UPPER LEVEL TROUGH MOVING THROUGH DENVER AT THIS TIME. THE INITIAL TROUGH IS PROGGED TO SHIFT TO THE NORTH AND EAST THIS MORNING...WITH MODERATE QG DESCENT IN THE MID AND UPPER LEVELS AFTER 12Z THIS MORNING. AREAS OF LIGHT SNOW IN THE HIGH COUNTRY WITH RAIN SHOWERS ALONG THE NORTHERN BORDER. MUCH OF THIS WILL DECREASE BY 15Z. GUSTY WINDS WILL PERSIST IN THE NORTHERN FOOTHILLS AND ALONG THE NORTHERN BORDER THIS MORNING. IT WILL BE COOLER TODAY WITH NORTHWESTERLY WINDS THIS MORNING BECOMING MORE NERLY LATE THIS MORNING AND INTO THE AFTN. FOR TONIGHT...THE QPF GENERATED BY MUCH OF THE MDLS IS FORECAST TO BE FURTHER SOUTH. AS A RESULT...HAVE LOWERED THE POPS OVER MUCH OF THE CWFA. BEST CHC OF SNOW TONIGHT WILL BE IN ZONES 36...37 AND 41. DO NOT ANTICIPATED MUCH IN THE WAY OF SNOW ACCUMULATION IN THOSE AREAS TONIGHT...MAYBE AN INCH OR TWO. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 333 AM MDT WED APR 16 2014 BY 12Z THURSDAY...MODELS SHOWING THAT THE SHORT WAVE WILL BE EAST OF COLORADO. WILL CONTINUE THE DOWNWARD TREND IN POPS FOR THURSDAY AND WILL ONLY MENTION A SLIGHT CHANCE FOR THE FAR EASTERN AREAS. AN UPPER LEVEL RIDGE AND WARMER AIR WILL BE QUICKER TO MOVE INTO THE AREA. RAISED HIGH TEMPERATURES FOR THURSDAY WITH MOST LOCATIONS CLIMBING INTO THE 60S. THE UPPER LEVEL RIDGE WILL MOVE ACROSS COLORADO FRIDAY CAUSING TEMPERATURES TO CLIMB INTO THE 70S OVER NORTHEAST COLORADO. A WEAK UPPER LEVEL LOW WILL MOVE FROM THE DESERT SOUTHWEST FRIDAY NIGHT INTO COLORADO ON SATURDAY. AT THE SURFACE...A COLD FRONT WILL PUSH SOUTH ACROSS EASTERN COLORADO. THERE WILL ONLY BE SLIGHT COOLING BEHIND THE FRONT AND MOST LOCATIONS ACROSS NORTHEAST COLORADO SHOULD STAY IN THE 60S. MOISTURE AND INSTABILITY WILL INCREASE WITH THIS SYSTEM. DURING THE AFTERNOON AND EVENING... EXPECT SCATTERED TO ISOLATED SHOWERS AND THUNDERSTORMS TO FORM. THIS SYSTEM WILL SHIFT EAST OF COLORADO SUNDAY. THIS WILL ALLOW TEMPERATURES TO WARM. MAY BE ENOUGH INSTABILITY AND MOISTURE FOR ISOLATED SHOWERS. PLAN ON KEEPING LOW POPS IN THE FORECAST FOR SUNDAY AFTERNOON AND EVENING. A RIDGE WILL MOVE ACROSS COLORADO ON MONDAY. ON TUESDAY...THE RIDGE WILL BE PUSHED EAST OF THE STATE BY A DEEP UPPER LEVEL LOW MOVING INTO THE GREAT BASIN. THIS WILL CAUSE FLOW ALOFT TO TURN SOUTHWEST TO SOUTHERLY AND INCREASE. THIS WILL PUMP WARM AND DRY AIR INTO THE STATE. COULD SEE HIGHS NEAR 80 ON TUESDAY IF ENOUGH WARM AIR IS TRANSPORTED INTO THE AREA. && .AVIATION...(FOR THE TAFS THROUGH 00Z THURSDAY AFTERNOON) ISSUED AT 1057 AM MDT WED APR 16 2014 FRONT HAS PASSED AREA AIRPORTS THIS MORNING...WITH MAINLY NORTHERLY WINDS. LATEST RAP AND HRRR INDICATING WINDS TO REMAIN A BIT MORE NORTHERLY THROUGH 21Z BEFORE BECOMING EASTERLY. WILL FOLLOW THIS TREND FOR THE UPCOMING ISSUANCE. OTHERWISE...CURRENT TAFS SEEM REASONABLE WITH SOUTHEAST WINDS DURING THE EVENING. STILL A SLIGHT CHANCE FOR SHOWERS AFTER 21Z...MAINLY AT KAPA AND KBJC. WILL MAINTAIN THE VCSH. CEILINGS COULD LOWER TO AROUND 5000 FEET AGL FOR A SHORT TIME...MAINLY AT KAPA. IMPROVING CONDITIONS OVERNIGHT AS SYSTEM MOVES AWAY FROM THE AREA. && .BOU WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...D-L SHORT TERM...COOPER LONG TERM...MEIER AVIATION...D-L
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
111 PM CDT WED APR 16 2014 .DISCUSSION... 313 AM CDT WEATHER WITHOUT ANY SIGNIFICANT IMPACTS LOOKS TO BE THE RULE THROUGH THE EARLY PART OF THE WEEKEND WITH MUCH OF THE ATTENTION ON TEMPERATURES AND WIND SPEEDS TODAY AND THEN SMALL CHANCES FOR PRECIPITATION THURSDAY NIGHT AND FRIDAY. TODAY AND TONIGHT... THE UPPER TROUGH RESPONSIBLE FOR THE CHILLY DAY YESTERDAY IS ADVANCING EAST OVER EASTERN CANADA AND NEW ENGLAND AND IS RESPONSIBLE FOR PORTIONS OF AT LEAST 22 STATES UNDER FREEZE WARNINGS THIS MORNING! STRONG MID-LEVEL DRYING IS SEEN ALL THE WAY DOWN TO THE NORTHERN GULF AND AT THE SURFACE THE DRY AIR HAS ADVANCED SOUTHWARD ALL THE WAY INTO THE GULF WITH SEVERAL PLATFORMS/BUOYS REPORTING DEW POINTS IN THE 30S. SO BASICALLY THE GULF IS NOT AVAILABLE FOR THE NEXT SYSTEM PASSING ACROSS THE REGION TONIGHT AND THAT WILL BE A MAIN REASON WE LOOK TO REMAIN PRECIPITATION FREE. THIS SYSTEM IS A FAIRLY WELL-DEFINED LOW AMPLITUDE UPPER WAVE THAT IS MOVING EAST ACROSS SD THIS MORNING AND WILL FOLLOW ITS PARENT JET STREAK/DIVERGENCE ALOFT TO THE EAST NORTHEAST OVER THE UPPER GREAT LAKES TONIGHT WHERE A SNOW STORM IS FORECAST ACROSS NORTHERN WI/U.P. OF MICHIGAN. THE QUICK EASTWARD PROGRESSION OF THE SYSTEM SURFACE LOW BY AFTERNOON WILL TIGHTEN THE PRESSURE GRADIENT ACROSS THE LOCAL AREA. WHILE THERE WILL BE SOME HIGH CLOUDS...MIXING WILL AID THE PRESSURE GRADIENT IN CREATING SUSTAINED SPEEDS AROUND 20 MPH AND GUSTS PLUS 10 MPH OF THAT. SOME 35 MPH GUSTS SHOULD EVEN BE REALIZED IN NORTH CENTRAL IL. TEMPERATURES LOOK TO BOUNCE BACK 15 DEGREES OR EVEN HIGHER THAN YESTERDAY GIVEN WARMING OF THE BOUNDARY LAYER AND LOW-LEVEL ADVECTION. A SLIGHT COMPONENT OFF THE LAKE INTO CITY OF CHICAGO AND NORTHWARD WILL KEEP THESE LAKE ADJACENT AREAS A HANDFUL OF DEGREES COOLER...BUT COMPARED TO 33 DEGREES YESTERDAY...THE FORECAST OF AROUND 50 TODAY FOR THESE LOCATIONS SHOULD BE WELCOME. OUTLYING AREAS LOOK TO REACH THE MID 50S. UPSTREAM DEW POINTS ARE IN THE UPPER TEENS TO MID 20S ACROSS DOWNSTATE IL/IN INTO THE TENNESSEE RIVER VALLEY...SO EXPECTING A FAIRLY DRY AIR MASS TODAY WITH HUMIDITY IN THE 25-35 PERCENT RANGE IN MOST AREAS. AS THE UPPER WAVE PASSES TO THE NORTH TONIGHT THE PACIFIC MOISTURE REMAINS NORTH AS WELL AND THE WARM AIR ADVECTION ASCENT HERE REMAINS WITHIN A LOW PWAT ATMOSPHERE. WOULD NOT BE SURPRISED TO SEE SOME RADAR ECHOES/VIRGA ACROSS FAR NORTHERN IL BUT THAT SHOULD BE ABOUT IT. WITH MORE CLOUD COVER TONIGHT AND SOUTHERLY WINDS OF 10-20 MPH CONTINUING...LOWS LOOK TO ONLY DIP INTO THE LOWER-MID 40S. THURSDAY AND FRIDAY... THE SYSTEM SURFACE FRONT/TROUGH IS EXPECTED TO MOVE INTO THE FORECAST AREA THURSDAY MORNING AND BECOME STATIONARY. THIS DOES NOT LOOK TO BE A VERY PRONOUNCED BAROCLINIC BOUNDARY. HAVE CONSIDERABLY LOWERED CLOUD COVER DURING THURSDAY MORNING AND EARLY AFTERNOON AND WITH THAT BOOSTED TEMPERATURES SOME...WITH 55 TO 60 PROBABLE. A SHEARING UPPER WAVE IS EXPECTED TO MOVE NORTHEAST OVER THE BOUNDARY THURSDAY NIGHT. A LOOK AT THE DPROG/DT...OR TREND...OF SEVERAL MODELS OVER THE PAST FOUR CYCLES SHOW CONSIDERABLY LESS FORCING AND MOISTURE AVAILABILITY FOR PRECIPITATION. HAVE CONTINUED THE FORECAST TREND TO CUT BACK POPS BUT ALSO TO CONFINE THE AREA WHERE CONVERGENCE/FRONTOGENESIS IS DEPICTED NEAR THE BOUNDARY. BY FRIDAY THE ENVELOPE OF GUIDANCE HAS FORCING EAST OF THE AREA...HOWEVER ONE FINAL SEPARATE MID-LEVEL IMPULSE SEEN ON THE NCEP MODELS PASSES OVER THE AREA FRIDAY AFTERNOON. CONTINUE A SMALL CHANCE OF RAIN SHOWERS WITH THIS. THE NORTH TO NORTHEAST FLOW BEHIND THE FRONT ON FRIDAY SHOULD LEAD TO A DECENT TEMPERATURE DIFFERENCE FROM NEAR THE LAKE TO OUTLYING AREAS...WITH MID 40S TO MID 50S PRESENTLY FORECAST ACROSS THAT CROSS SECTION. LOCAL CLIMATOLOGICAL RESEARCH FAVORS SUCH A SPREAD THIS TIME OF YEAR WITH ONSHORE FLOW. THIS WEEKEND INTO EARLY NEXT WEEK... WHILE THE FLOW IS PROGRESSIVE ACROSS THE FAR NORTHERN CONUS/SOUTHERN CANADA IT LOOKS TO BE FAR ENOUGH NORTH TO HAVE LITTLE INFLUENCE ON THE AREA SATURDAY AND POTENTIALLY EVEN SUNDAY...ESPECIALLY IF GOING TOWARD THE EC AND GEM WHICH WE HAVE LEANED OUR FORECAST. THESE MODELS INDICATE THAT A CLOSED UPPER LOW OVER THE SOUTHEAST U.S. DEPICTED BY MODELS LATE IN THE WEEKEND MAY LEAD TO A SLOWING OF THE NEXT SYSTEM TO APPROACH THE AREA FROM THE ROCKIES...MORE SO SUNDAY NIGHT AND MONDAY. TEMPERATURES LOOK TO BE BACK TO NORMAL SUNDAY AND MONDAY. MTF && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 18Z... * STRONG SSE WINDS AND GUSTS POSING POTENTIAL CROSSWIND ISSUES THIS AFTERNOON AND EVENING. * LLWS POSSIBLE OVERNIGHT AS GUSTS DIMINISH. LENNING //DISCUSSION...UPDATED 18Z... A LOW PRESSURE CENTER LIFTING ACROSS IOWA INTO WISCONSIN TODAY AND TONIGHT WILL SUPPORT GUSTY SSE WINDS OVER THE LOCAL TERMINALS TODAY. GUSTS SHOULD DIMINISH OVERNIGHT WITH SFC COOLING AND BETTER LOW LEVEL STABILITY...THOUGH STRONG WINDS ALOFT MAY CREATE MARGINAL LLWS CONDITIONS. WINDS GRADUALLY TURN SOUTHWEST TOWARD MORNING THEN AROUND TO THE WEST LATE TOMORROW AFTER THE LOW CROSSES LAKE SUPERIOR AND A TRAILING COLD FRONT PASSES THROUGH THE AREA. PRECIP CHANCES WITH THIS SYSTEM APPEAR LOW UNTIL LATE TOMORROW. LENNING //ORD AND MDW CONFIDENCE...UPDATED 18Z... * HIGH CONFIDENCE IN ALL ELEMENTS EXCEPT FOR LLWS TONIGHT. LENNING //OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z... THURSDAY NIGHT...CHC RAIN. MVFR PSBL. FRIDAY...SLT CHC RAIN. MVFR PSBL. SATURDAY...VFR. SUNDAY...CHC RAIN. MONDAY...SLT CHC RAIN. TUESDAY...VFR. BMD && .MARINE... 242 AM CDT HIGH PRESSURE WILL CONTINUE TO MOVE AWAY FROM LAKE MICHIGAN TODAY WHILE LOW PRESSURE MOVES EAST ACROSS THE NORTHERN PLAINS ALLOWING A SOUTHERLY GRADIENT TO SET UP ACROSS LAKE MICHIGAN. WINDS WILL STEADILY INCREASE THROUGH THE DAY TOPPING OUT AROUND 30 KT THIS EVENING AND TONIGHT. A SMALL CRAFT ADVISORY REMAINS IN EFFECT FOR THE INDIANA AND ILLINOIS NEARSHORE WATERS TODAY THROUGH TONIGHT. STABLE CONDITIONS WILL PREVENT STRONGER WINDS FROM REACHING THE LAKE SURFACE. THE LOW WILL BEGIN TO FILL THURSDAY AS IT LIFTS ACROSS FAR NORTHERN LAKE MICHIGAN...THEN HIGH PRESSURE WILL BUILD OVER LAKE MICHIGAN LATE IT THE WEEK INTO THE WEEKEND. BMD && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS UNTIL 4 AM THURSDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion National Weather Service Lincoln IL 1219 PM CDT Wed Apr 16 2014 .DISCUSSION... ISSUED 1021 AM CDT WED APR 16 2014 Low pressure in South Dakota will move east into Iowa and then northeast toward Lake Huron. As it progresses, a warm front will lift across IL, putting our forecast area in the warm sector by this evening. During the day, southerly winds will increase as the pressure gradient tightens between departing high pressure and the SD low. 12z RAP forecast soundings show mixing heights up to 825-850 mb. That should allow momentum transfer of wind speeds around 25 mph with some gusts to 35 mph. We expect to remain below wind advisory criteria of 30-39 mph sustained winds for an hour or more. Peak winds appear to be in the Noon to 3 pm time frame. Mixing of dry air from the mid levels will help the surface temps climb about 10 to 15 deg warmer than yesterday. Lightly filtered sunshine will also help boost high temps, with readings in the mid to upper 50s by 3-4 pm. We should remain dry until the cold front pushes across IL sometime late Thursday/Thursday night. Still, limited moisture will keep rain chances and amounts on the low side. Our current forecast grids look on track over the next 12-24 hours, especially temps, dewpoints, winds and sky. No formal update will be needed this morning. Shimon && .AVIATION... ISSUED 1218 PM CDT Wed Apr 16 2014 pressure gradient between 1032 MB high over the eastern Great Lakes and a slowly filling Great Plains low is producing winds gusts around 30 kts at terminals at midday. Gust should diminish slowly this afternoon as high moves further east and the low continues to fill. Winds should diminish even more quickly around 00z. A weak pre-frontal trough associated with the low is expected to move into Illinois Thursday afternoon and produce a wind shift to the northwest. An increase in clouds and the development of CIGs is likely late tonight and Thursday as a series of fast-moving northern stream waves move across the Midwest. low-level moisture is lacking and any CIGs are expected to remain IFR. Barker && .PREV DISCUSSION... ISSUED 249 AM CDT WED APR 16 2014 SHORT TERM...Today through Friday Winds will increase markedly across central Illinois today as gradient tightens between departing high pressure system and low tracking from the Dakotas into southern Minnesota. Models are not quite as strong with the winds as they were in previous runs, so am not concerned about reaching Wind Advisory criteria. BUFKIT momentum transfer at KPIA shows 33kt winds at the top of the mixed layer this afternoon, as opposed to 43kt on the prior run just 24 hours ago. Despite this decrease in momentum, think S/SE winds will gust to between 30 and 35mph across the western half of the KILX CWA, with gusts to around 25mph further east near the Indiana border. This strong southerly flow will help bring much warmer air into the region. Extent of warming will be mitigated somewhat by an easterly component to the wind and mixing heights lowering to less than 5000ft. Resulting afternoon highs will range from the middle 50s east to around 60 far west. As southern Minnesota low lifts toward Lake Superior, it will drag a weak cold front into the Illinois River Valley by dawn Thursday. This boundary will become stationary along the I-55 corridor during the day Thursday, creating little in the way of sensible weather. A mid-level short-wave will approach from the southwest late in the day and will eventually interact with the front to perhaps produce a few light showers. Current surface analysis shows a very dry air mass has settled across the eastern half of the CONUS all the way to the Gulf of Mexico. In fact, buoys in the northern Gulf are currently showing dew points as low as the middle to upper 30s. With so much dry air to the south, do not think front will have enough moisture to work with in order to produce precip across the area on Thursday. GFS is the only model that is holding on to QPF across the Illinois River Valley Thursday afternoon, but think this is overdone. Will therefore go with a dry forecast across the board. There are even some indications that dry conditions will continue Thursday night into Friday as the upper wave arrives. At this point, will leave chance PoPs for showers in the forecast Thursday night into Friday morning as synoptic lift associated with the wave will likely be enough to squeeze a few light showers out of the dry air mass. Once the wave passes, dry weather will return Friday afternoon and night. LONG TERM...Saturday through Tuesday After a warm/dry day on Saturday, attention turns to next approaching system for early next week. Models have been trending slower with its approach, with most 00z Apr 16 guidance suggesting Easter Sunday may remain largely dry. GFS is the most aggressive model in driving precip eastward into the area, but even it has backed off and keeps rain at bay until Sunday afternoon at the earliest. GEM focuses best rain chances Sunday night into Monday, while ECMWF is even slower and advertises mainly a Monday rain event. As a result of the distinct slowing trend, have trimmed PoPs accordingly. Will keep Saturday night and Sunday morning dry, then will bring chance PoPs into the picture across the western CWA Sunday afternoon. Will highlight the Sunday night/Monday time frame with the highest PoPs, followed by a return to dry weather on Tuesday. Aside from the early week rain chances, the extended forecast will feature warmer weather, with model guidance suggesting temps reaching the 70s by Tuesday. Barnes && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1239 PM CDT WED APR 16 2014 .UPDATE... ISSUED AT 1235 PM CDT WED APR 16 2014 CONDITIONS REMAIN MARGINAL FOR A RED FLAG WARNING OR EVEN A WIND ADVISORY AT THIS TIME. NO HEADLINES EXPECTED. SURFACE CYCLONE NEAR SIOUX FALLS SD ALREADY BEGINNING TO FILL/WEAKEN WITH ISALLABARIC ANALYSIS SHOWING THE BEST PRESSURE FALLS IN SW WI. IR SATELLITE LOOPS INDICATE A CLASSIC MATURE COMMA HEAD SHAPE TO THIS MID LATITUDE STORM SYSTEM ACROSS THE UPPER MIDWEST. A STRONG VORT MAX WAS NOTED IN NORTHEAST NEB. ALL OF THE PRECIPITATION IS OCCURRING ON THE COLD SIDE OF THE STORM AND MOSTLY IN THE FORM OF SNOW...FROM CENTRAL MN INTO NORTHERN WI. IN THE WARM SECTOR THE AIRMASS WAS VERY DRY AS A STRONG HIGH PRESSURE RIDGE EXTENDS FROM THE MID ATLANTIC TO THE GULF OF MEXICO. SURFACE DEWPOINTS WERE IN THE 20S AND 30S ALL THE WAY FROM IA TO TX. THERE WAS ALSO A TIGHT PRESSURE GRADIENT WITH WINDS GUSTING TO 30 TO 40 MPH ACROSS MUCH OF THE CWA. AS THE CYCLONE WEAKENS AND MOVES INTO WI THIS EVENING THE WINDS SHOULD BEGIN TO DIMINISH. MESO MODELS INDICATE A BAND OF VERY LIGHT SHOWERS OR SPRINKLES MAY PUSH ACROSS EASTERN IA THIS EVENING AS PVA SWEEPS THROUGH...BUT WEAKENS AS IT TRACKS FARTHER TO THE EAST AS THE DRY LOW LEVELS WIN THE BATTLE. FOR THE MOST PART TEMPERATURES AND DEW POINTS ARE ON TARGET SO ONLY MINOR CHANGES HAVE BEEN MADE TO THE UPDATED FORECAST THIS MORNING. CURRENT TEMPERATURES RANGED FROM THE MID 40S TO THE MID 50S. && .SYNOPSIS... ISSUED AT 406 AM CDT WED APR 16 2014 HIGH PRESSURE RIDGE HAS MOVED INTO THE OHIO VLY WHILE A 998 MB SFC CYCLONE WAS LOCATED SOUTH OF PIERRE SD AT 07Z. SOUTHEAST WINDS ARE STRENGTHENING OVER THE AREA IN TIGHTENING PRESSURE GRADIENT RESULTING IN STEADY TO RISING TEMPS. PATTERN ALOFT FEATURES FAST SEMI-ZONAL FLOW OVER REGION AHEAD OF SHORTWAVE TRAVERSING NORTHERN ROCKIES. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 406 AM CDT WED APR 16 2014 CRITICAL FIRE WEATHER AND WIND ADVISORY CONCERNS DOMINATE THE FCST. SFC CYCLONE OVER SD WILL MOVE EAST INTO WI BY EARLY THURSDAY AM. TRAILING COLD FRONT WILL MOVE INTO CWA LATER THIS EVENING AND MOVE EAST AND SHOULD BE NEAR OR JUST EAST OF MISSISSIPPI RIVER BY 12Z THURSDAY. WARM SECTOR OF SYSTEM IS MOISTURE STARVED AND THUS MOST OF PCPN THAT OCCURS DURING PERIOD WILL BE RIGHT AHEAD AND NORTH OF SFC CYCLONE TRACK. WILL THOUGH HAVE SMALL CHCS FOR LIGHT RAIN WITH FRONT TONIGHT MAINLY NORTHEAST IA BEING IN CLOSER PROXIMITY TO PV ANOMALY AND VORTICITY ADVECTION. VERY STRONG LOW LEVEL JET WITH 850 MB WINDS OF 50-60 KTS TO FOCUS MAINLY WEST OF CWA THIS AM THEN SHIFT INTO AREAS WEST OF MISSISSIPPI RIVER THIS AFTN BUT WEAKENING TO NEAR 40 KTS. NONETHELESS...TIGHTENING PRESSURE GRADIENT AND DEEP MIXING TAPPING STRONGER WINDS ALOFT SHOULD GENERATE SUSTAINED SOUTHEAST TO SOUTH WINDS AT 20-25 KTS WITH GUSTS AROUND 35 KTS... CLOSE TO WIND ADVISORY CRITERIA WHICH WILL NEED TO BE MONITORED IN CASE AN ADVISORY BECOMES NEEDED...BUT ENOUGH UNCERTAINTY WITH CLOUDS AND POTENTIAL IMPACTS ON MIXING AND NOTED WEAKENING TRENDS ON WINDS ALOFT FROM LATEST RUC AND NAM TO HOLD OFF ON ISSUING ATTM. STRONG WINDS WILL AID IN ELEVATED FIRE DANGER TODAY...WITH MAIN CHALLENGE BEING LOW LEVEL MOISTURE AND MODELS HANDLING WHICH WILL LOOM LARGE AS TO WHETHER RED FLAG WARNING CRITERIA IS ACHIEVED IN SOME AREAS. DEEP MIXING TO AT OR ABOVE 800 MB IF REALIZED FROM NAM/RUC SOUNDINGS WOULD YIELD SUBSTANTIAL DROP IN DEWPTS INTO THE TEENS TO LOWER 20S ALL BUT FAR WESTERN CWA THIS AFTN. AND THESE LOW DEWPTS CERTAINTLY SHOW UP IN LOOKING BACK AT UPSTREAM OBS IN SIMILAR REGIME YSTDY. UNCERTAINTY WITH HOW MUCH RECENT HEAVY RAINS AND CONTINUED GREENING UP TO IMPACT OR OFFSET DRYING ATTENDANT TO DEEP MIXING. THIS IS DISCUSSED FURTHER IN FIRE WEATHER SECTION BELOW. HIGHS TODAY WITH MIXING AND PROGGED LOW LEVEL THICKNESS AND VERIFICATION FROM YSTDY ALONG WITH BOUTS OF MID/HIGH CLOUDINESS SUPPORT LOWERING MAXES FEW DEGS ESPECIALLY NORTHEAST 1/3-1/2. OVERALL... VERIFICATION SUPPORTS HIGHS RANGING FROM 50-55F NORTHEAST TO LOWER 60S SOUTHWEST. TEMPS MILD MOST OF TONIGHT HELD UP BY BREEZY SOUTH/SOUTHWEST WINDS WITH TEMPS FALLING LATE WITH FRONTAL PASSAGE WITH MID 30S WEST/NORTHWEST TO LOWER 40S EAST/SOUTHEAST. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 406 AM CDT WED APR 16 2014 FORECAST FOCUS IN THE EXTENDED IS ON CONTINUED BELOW NORMAL TEMPERATURES THROUGH THE REST OF THE WORK WEEK WITH SMALL PCPN CHANCES ACROSS THE SOUTHEAST THURSDAY NIGHT/FRIDAY MORNING. TEMPERATURES TO RETURN TO NORMAL THIS WEEKEND AND POSSIBLY ABOVE NORMAL EARLY NEXT WEEK. THURSDAY...WEAK COLD FRONT TO BE JUST EAST OF CWA IN THE MORNING WITH PARENT LOW LIFTING NORTHEAST INTO THE GREAT LAKES. LINGERING CLOUDS...WEST WINDS...AND MIXING TO AROUND 900MB WILL KEEP TEMPERATURES WELL BELOW NORMAL WITH AFTERNOON READINGS IN THE UPPER 40S NORTH TO MIDDLE 50S SOUTH. ONE CONCERN IS CLOUD TRENDS AND IF CLOUDS CLEAR OUT...THAN FORECAST MAX TEMPS MAY BE A FEW DEGREES TOO COLD. THURSDAY NIGHT-FRIDAY...SHORTWAVE TO TRACK OVER THE SOUTHERN PLAINS LIFTING NORTHEAST NEAR THE CWA AROUND MIDNIGHT. LOW LEVEL CONVERGENCE AND MOISTURE TRANSPORT INCREASES ACROSS THE FAR SOUTHEAST WITH LIGHT RAIN SHOWERS BREAKING OUT MAINLY SOUTH AND EAST OF A LINE FROM KIRKSVILLE MISSOURI TO PRINCETON ILLINOIS. MOISTURE AVAILABILITY IS VERY LIMITED SO QPF AMOUNTS WILL BE A FEW HUNDREDTHS OF AN INCH. ONE THING OF NOTE IS THE LATEST NAM SOLUTION HAS A NON-EVENT FOR THIS PERIOD WHICH WAS MUCH DIFFERENT THAN ITS PREVIOUS RUN. ANOTHER VERY INTERESTING THING IS THAT THE NEW 00Z NAM/GFS BOTH HAVE A SHORTWAVE COMING DOWN FROM CANADA IMPACTING THE CWA WITH CLOUDS AND PCPN CHANCES FRIDAY. THE NON-AMERICAN SOLUTIONS (ECMWF/GEM/UKMET) ALL SAY OTHERWISE AND HAVE DRY FORECASTS. SIDED WITH THE NON-AMERICAN SOLUTIONS GIVEN THAT THE NAM/GFS HAVE BEEN NOTORIOUSLY TOO MOIST IN THE LOW LEVELS THIS SPRING. HIGH TEMPERATURES FRIDAY TO BE A LITTLE WARMER THAN THURSDAY BUT STILL BELOW NORMAL. THIS WEEKEND...MODELS CONTINUE TO SHOW A STORM SYSTEM TRACKING ACROSS SOUTHERN CANADA WITH A COLD FRONT MOVING ACROSS THE MIDWEST. AHEAD OF THIS FRONT...TEMPERATURES WILL WARM NICELY WITH 85H TEMPS PROGGED TO BE IN THE +6 TO 10C RANGE BY 00Z SUNDAY. HIGHS OVER THE WEEKEND TO BE IN UPPER 50S/LOW 60S SATURDAY AND IN THE 60S AREA WIDE ON SUNDAY. FORCING AND LOW LEVEL MOISTURE INCREASES SUNDAY AHEAD OF COLD FRONT WITH LIGHT TO POSSIBLY MODERATE RAIN FALLING SOMETIME DURING THE DAY. MODEL CONSENSUS HAS CHANCE POPS AT THIS TIME FOR SUNDAY. EARLY NEXT WEEK...WARM AND DRY CONDITIONS WILL BE FOUND AS HIGH PRESSURE DRIFTS ACROSS THE MIDWEST. TEMPERATURES TO AVERAGE ABOVE NORMAL WITH HIGHS WELL INTO THE 60S AND LOWER 70S. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 1235 PM CDT WED APR 16 2014 VFR CONDS THROUGH THIS TAF CYCLE. SOUTH WINDS SUSTAINED AT 20 TO 25 KNOTS WITH GUSTS TO 30 TO 35 KNOTS THIS AFTERNOON INTO THIS EVENING BEFORE DIMINISHING AND VEERING TO THE WEST OVERNIGHT. WEST TO NORTHWEST WINDS AROUND 10 KNOTS ON THURSDAY MORNING. && .FIRE WEATHER... ISSUED AT 406 AM CDT WED APR 16 2014 SOUTHEAST TO SOUTH WINDS WILL INCREASE TO NEAR ADVISORY CRITERIA AT TIMES LATE THIS MORNING THROUGH AFTERNOON WITH SUSTAINED SPEEDS AT 20-30 MPH AND GUSTS TO NEAR 40 MPH. MAIN QUESTION/CONCERN IS WITH SURFACE DEW POINTS AND SUBSEQUENT RELATIVE HUMIDITY VALUES. MODEL GUIDANCE SUPPORTIVE OF DEW POINTS IN THE 20S TO LOWER 30S WHICH COMBINED WITH TEMPS IN THE 50S TO LOWER 60S WOULD YIELD RELATIVE HUMIDITY VALUES MAINLY IN THE 30S. HOWEVER...DEEP MIXING AIDED BY SOUTHEAST FETCH OFF DEPARTING HIGH PRESSURE RIDGE WOULD SUPPORT SUBSTANTIALLY LOWER DEW POINTS AND RELATIVE HUMIDITY VALUES IN THE TEENS AND 20S. ALSO ADDING TO THE UNCERTAINTY IS DEGREE OF IMPACTS IF ANY OF RECENT HEAVY RAINS AND CONTINUED GREENING UP. IF THE LOWER VALUES OCCUR THEN IT WOULD LEAD TO VERY HIGH TO EXTREME GRASSLAND FIRE DANGER INDEX VALUES AND LIKELY NECESSITATE RED FLAG WARNING PORTIONS OF AREA. ENOUGH UNCERTAINTY PRECLUDES ISSUANCE OF RED FLAG WARNING AT THIS TIME... BUT WILL NEED TO MONITOR DEW POINT AND RELATIVE HUMIDITY LEVELS CAREFULLY FOR POTENTIAL OF NEEDING HEADLINE. FIRE DANGER ELEVATED TO POSSIBLY HIGH OVER DRY GRASSES AND CURED VEGETATION. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ UPDATE...HAASE SYNOPSIS...05 SHORT TERM...05 LONG TERM...GROSS AVIATION...HAASE FIRE WEATHER...05
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
434 PM EDT WED APR 16 2014 .SYNOPSIS... COOL HIGH PRESSURE SETTLES OVER THE MID ATLANTIC AND NORTHEAST STATES TONIGHT. THE HIGH WILL BECOME CENTERED FROM NEW ENGLAND TO THE CANADIAN MARITIMES THURSDAY AND FRIDAY...MAINTAINING NORTHEAST FLOW AND MUCH COOLER THAN AVERAGE TEMPERATURES ACROSS THE REGION. A COLD FRONT WILL CROSS THE AREA FRIDAY NIGHT WITH HIGH PRESSURE RETURNING FOR SATURDAY. && .NEAR TERM /THROUGH THURSDAY/... HIGH PRESSURE CENTERED OVER NEW YORK THIS EVENING WILL MOVE NORTHEAST AND BECOME CENTERED OVER NORTHERN NEW ENGLAND ON THURSDAY. THE HIGH WILL RIDGE DOWN OVER THE AREA TONIGHT. WINDS WILL BE LIGHT OVER THE INTERIOR SECTIONS OF THE FA TONIGHT. THIS COMBINED WITH THE STILL COLD AIR MASS IN PLACE AND CLEAR SKIES OVERHEAD WILL LEAD TO ANOTHER WIDESPREAD FREEZE EVENT. TEMPERATURES WILL DROP INTO THE UPPER 20S AND LOW 30S. HAVE ISSUED A FREEZE WARNING FOR THIS AREA. FARTHER TO THE EAST...THE WINDS WILL TURN MORE NORTHEAST AND COME OFF THE WATER. THIS WILL HELP KEEP TEMPERATURES UP SOME WITH LOWS IN THE UPPER 30S TO LOW 40S. ALSO THE NAM AND RUC BOTH INDICATE SOME INCREASE IN MOISTURE AROUND 950 MB TONIGHT WITH THE EAST FLOW DEVELOPING THERE. NOT SURE THE EXTENT TO WHICH CLOUDS WILL RETURN BUT WENT AHEAD AND DEVELOPED CLOUDS ACROSS THE SOUTHEASTERN PART OF THE AREA OVERNIGHT. ON THURSDAY THESE CLOUDS SHOULD SLOWLY SPREAD TO THE WEST AND NORTH AS MORE LOW LEVEL MOISTURE IS BROUGHT IN OFF THE ATLANTIC. ANOTHER COLD DAY ON THURSDAY WITH TEMPERATURES IN THE 50S. THE WARMEST TEMPERATURES WILL BE IN WESTERN SECTIONS WHERE THE CLOUDS WILL BE THE LEAST AND FARTHER AWAY FROM THE OCEAN INFLUENCE. && .SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/... MODELS ALL AGREE ON A TROUGH DEVELOPING JUST OFF THE SOUTHEAST COAST THURSDAY NIGHT INTO FRIDAY NIGHT. THIS IS DUE TO SOME SOUTHERN STREAM ENERGY MOVING ALONG ACROSS THE SOUTHERN US. THIS ENERGY IS NOT WELL HANDLED BY ANY OF THE MODELS SO THERE IS PLENTY OF UNCERTAINTY. HAVE LEANED MORE TOWARD THE DRIER NAM BUT WILL BRING SLIGHT CHANCE POPS IN FOR FRIDAY NIGHT OVER THE EASTERN THIRD OF THE AREA WITH CHANCE POPS OVER PARTS OF NORTHEAST NORTH CAROLINA. TEMPERATURES WILL BECOME MILDER THROUGH THE PERIOD. GENERALLY FOLLOWED MOS GUIDANCE WHICH KEEPS MOST MINS IN THE 40S THURSDAY NIGHT AND HIGHS ON FRIDAY BACK INTO THE 60S. BY LATE FRIDAY NIGHT ALL MODELS AGREE ON A WEAK COLD FRONT CROSSING THE AREA WITH ANOTHER HIGH PRESSURE BUILDING IN FROM THE WEST. THIS WILL CLEAR THE SKIES ACROSS THE AREA AS IT PUSHES THE TROUGH FARTHER OFF THE COAST. LOWS FRIDAY NIGHT WILL BE IN THE 40S WITH HIGH TEMPERATURES ON SATURDAY GETTING BACK TO AROUND NORMAL IN THE LOW 70S. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... A LONG AREA OF HIGH PRESSURE MOVING ACROSS SOUTHEAST CANADA WILL EXTEND INTO THE ERN GREAT LAKES AND OH/TN VALLEYS SAT NIGHT. MEANWHILE...A COASTAL LOW OFF THE SOUTHEAST COAST IS NOW EXPECTED TO STAY SHUNTED WELL SOUTH OF THE AREA SAT NIGHT AND THEN TRACK NE WELL OFF THE CAROLINA COAST THROUGH SUN. THE STRETCHED OUT SFC HIGH AND ASSOCIATED MID/UPPER RIDGING WILL PASS OVER THE MID ATLANTIC REGION SUN INTO EARLY MON. THE SFC HIGH THEN SLIDES OFF THE COAST DURING THE DAY AS THE MID/UPPER RIDGING FLATTENS. A RELATIVELY FLAT (WEST TO EAST ORIENTED) FRONTAL BOUNDARY SAGS DOWN INTO THE AREA MON NIGHT INTO TUE...MOVING OFFSHORE BY WED MORNING. WEAK SHORTWAVE ENERGY AND A SUBSEQUENT SFC LOW TRAVELING ALONG THIS BOUNDARY MAY BRING ANOTHER SHOT OF PRECIPITATION TO THE AREA ON MON/TUE. GFS PRECIP-GENERATION AND GENERAL MOVEMENT CONTINUES TO BE AGGRESSIVE/FAST VERSUS THE ECMWF. HAVE THEREFORE TRIED TO SPLIT THE DIFFERENCE WITH THE POP FORECAST...LEANING TWD SLIGHTLY SLOWER TIMING TO THE ONSET OF PRECIP MON NIGHT AND LIMITING OVERALL COVERAGE ON TUE TO NO HIGHER THAN 40 PERCENT. TEMPERATURES ARE EXPECTED TO BE STRAIGHT-FORWARD SAT NIGHT THROUGH SUN NIGHT AS HIGH PRESSURE CROSSES THE REGION. EXPECT LOWS NEAR NORMAL BOTH NIGHTS IN THE 40S (LOWER 50S POSSIBLE IMMEDIATE SE VA/NE NC COASTS). HIGHS SAT/SUN RANGE FROM ROUGHLY 65 DEGREES FAR NE TO 70 DEGREES SW. AS THE FLAT FRONTAL BOUNDARY STARTS TO SAG INTO THE MID ATLANTIC STATES MON THROUGH WED...THE TEMP FORECAST BECOMES TRICKY IN REGARD TO WHERE EXACTLY THE WARM SECTOR DEVELOPS. WITH PRECIP EXPECTED TO MOVE INTO THE AREA AT SOME POINT MON NIGHT...INCREASING CIRRUS DURING THE DAY MON SHOULD KEEP HIGH TEMPS IN THE UPPER 60S WEST OF I-95 WITH WARMER TEMPS IN THE LOWER 70S EAST OF I-95 (MID-UPPER 60S MD/VA EASTERN SHORE). HIGHS TUE SHOULD BE IN THE LOW-MID 70S INLAND AND IN THE UPPER 60S NEAR THE IMMEDIATE CHES BAY AND ATLANTIC COASTS. THE WARMING TREND CONTINUES WITH HIGHS ON WED IN THE MID 70S INLAND TO UPPER 60S AT THE IMMEDIATE COAST. LOW TEMPERATURES AREAWIDE ON MON/TUE/WED NIGHTS SHOULD ALSO BE WARM WITH READINGS IN THE 50S (OR ABOUT 10 DEGREES ABOVE NORMAL). && .AVIATION /20Z WEDNESDAY THROUGH MONDAY/... A MAINLY CLEAR SKY IS EXPECTED THROUGH EARLY THURSDAY MORNING. GUSTY N WINDS BECOME NE THIS AFTERNOON AND SLOWLY DIMINISH TOWARD EVENING. WINDS HAVE TENDED TO BE SLIGHTLY BACKED FROM MOS FORECASTS AND MADE ADJUSTMENTS ACCORDINGLY. NE WINDS MAY BE GUSTY ONCE AGAIN THURSDAY. STRATOCU CLOUDS WHICH COULD GO MVFR DEVELOP OVER SE VA/NE NC TAF SITES THURSDAY MORNING ASSOCIATED WITH ONSHORE FLOW. OUTLOOK...AS HIGH PRESSURE STRENGTHENS OVER NEW ENGLAND AND THE CANADIAN MARITIMES...THE CHANCES FOR MVFR CONDS INCREASE THROUGH FRIDAY NIGHT...ESPECIALLY SE PORTIONS. THERE WILL ALSO BE A CHANCE FOR SHOWERS LATE FRIDAY AND FRIDAY NIGHT. A COLD FRONT MOVES THROUGH EARLY SATURDAY BUT THE TREND TOWARD ONSHORE FLOW WILL CONTINUE INTO EARLY NEXT WEEK. && .MARINE... SCA FLAGS NOW IN EFFECT THROUGH EARLY THU AFTN FOR ERN VA RIVERS AND NRN CHES BAY...AND THROUGH THU EVENING FOR SRN CHES BAY. AS HIGH PRESSURE SLIDES ACROSS NEW ENGLAND TONIGHT INTO FRIDAY... WINDS TURN TO THE NE AND ANOTHER PUSH OF COLD AIR (ALBEIT WEAKER) IS ANTICIPATED TO OCCUR OVERNIGHT INTO EARLY THU AFTN...WHICH WILL INCREASE SPEEDS INTO SCA THRESHOLDS DURING THIS TIME. ALSO...THE PERSISTENT ONSHORE FLOW WILL CAUSE SEAS TO REMAIN AT OR ABOVE 5 FT FOR ALL COASTAL WATERS THROUGH FRI EVENING. PROLONGED SCA FLAGS ARE NOW IN EFFECT FOR THE COASTAL WATERS DURING THIS TIMEFRAME BUT WILL LIKELY BE EXTENDED THROUGH SAT DUE TO SEAS STAYING AT OR ABOVE 5 FT IN PERSISTENT NE/ONSHORE FLOW. THE NEXT BEST CHANCE FOR SCA CONDITIONS APPEARS TO BE SAT NIGHT INTO SUN MORNING AS A WEAK LOW PASSING ACROSS NRN NEW ENGLAND PUSHES A WEAK BACKDOOR TROUGH AND A COOLER AIRMASS ACROSS THE WATERS. WIND DIRECTION REMAINS IN AN ONSHORE DIRECTION AND SEAS COULD BRIEFLY REACH ABOVE 5 FT AGAIN. && .CLIMATE... RECORD LOW MAXIMUM TEMPERATURES TODAY 4/16: RIC...45 (1929) ORF...46 (1935) SBY...45 (1935) ECG...52 (1962 & 1952) RECORD LOWS THU 4/17: RIC...31 (1949) ORF...34 (1875) SBY...26 (2008) && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...FREEZE WARNING FROM 2 AM TO 9 AM EDT THURSDAY FOR MDZ021>023. NC...FREEZE WARNING FROM 2 AM TO 9 AM EDT THURSDAY FOR NCZ012. VA...FREEZE WARNING FROM 2 AM TO 9 AM EDT THURSDAY FOR VAZ048-049- 060>083-085-087>089-092. MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT FRIDAY FOR ANZ633-650-652- 654-656-658. SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO 1 PM EDT THURSDAY FOR ANZ635>637. SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT THURSDAY NIGHT FOR ANZ632-634. SMALL CRAFT ADVISORY UNTIL 1 PM EDT THURSDAY FOR ANZ630-631- 638. && $$ SYNOPSIS...JAB NEAR TERM...JAB SHORT TERM...JAB LONG TERM...BMD AVIATION...LSA MARINE...BMD CLIMATE...AKQ
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
337 PM EDT WED APR 16 2014 .SYNOPSIS... COOL HIGH PRESSURE SETTLES OVER THE MID ATLANTIC AND NORTHEAST STATES TONIGHT. THE HIGH WILL BECOME CENTERED FROM NEW ENGLAND TO THE CANADIAN MARITIMES THURSDAY AND FRIDAY...MAINTAINING NORTHEAST FLOW AND MUCH COOLER THAN AVERAGE TEMPERATURES ACROSS THE REGION. A COLD FRONT WILL CROSS THE AREA FRIDAY NIGHT WITH HIGH PRESSURE RETURNING FOR SATURDAY. && .NEAR TERM /THROUGH THURSDAY/... HIGH PRESSURE CENTERED OVER NEW YORK THIS EVENING WILL MOVE NORTHEAST AND BE CENTERED OVER NORTHERN NEW ENGLAND ON THURSDAY. THE HIGH WILL RIDGE DOWN OVER THE AREA TONIGHT. WINDS WILL BE LIGHT OVER THE INTERIOR SECTIONS TONIGHT. THIS COMBINED WITH THE STILL COLD AIR MASS AND CLEAR SKIES WILL LEAD TO ANOTHER WIDESPREAD FREEZE EVENT. TEMPERATURES WILL DROP INTO THE UPPER 20S AND LOW 30S. HAVE ISSUES A FREEZE WARNING FOR THIS AREA. FARTHER TO THE EAST THE WINDS WILL TURN MORE NORTHEAST AND COME OFF THE WATER. THIS WILL HELP KEEP TEMPERATURES UP SOME WITH LOWS IN THE UPPER 30S TO LOW 40S. ALSO THE NAM AND RUC BOTH INDICATE SOME INCREASE IN MOISTURE AROUND 950 MB TONIGHT WITH THE EAST FLOW DEVELOPING THERE. NOT SURE HOW MUCH CLOUDS WILL RETURN BUT DID DEVELOP CLOUDS ACROSS THE SOUTHEASTERN PART OF THE AREA OVERNIGHT. ON THURSDAY THESE CLOUDS SLOWLY SPREAD TO THE WEST AND NORTH AS MORE LOW LEVEL MOISTURE IS BROUGHT IN OFF THE ATLANTIC. ANOTHER COLL DAY ON THURSDAY WITH TEMPERATURES IN THE 50S. THE WARMEST TEMPERATURES WILL BE IN WESTERN SECTIONS WHERE THE CLOUDS WILL BE THE LEAST AND FARTHER AWAY FROM THE OCEAN INFLUENCE. && .SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/... MODELS ALL AGREE ON TROUGHING DEVELOPING JUST OF THE COAST THURSDAY NIGHT AND INTO FRIDAY NIGHT. THIS IS DUE TO SOME SOUTHERN STREAM ENERGY MOVING ALONG ACROSS THE SOUTHERN US. THIS ENERGY IS NOT WELL HANDLED BY ANY OF THE MODELS SO WILL PLENTY OF UNCERTAINTY. HAVE LEANED MORE TOWARD THE DRIER NAM BUT WILL BRING SLIGHT CHANCE POPS IN FOR FRIDAY NIGHT OVER THE EASTERN THIRD OF THE AREA WITH CHANCE POPS OVER PARTS OF NORTHEAST NORTH CAROLINA. TEMPERATURES WILL BECOME MILDER THROUGH THE PERIOD. GENERALLY FOLLOWED MOS GUIDANCE WHICH KEEPS MOST MINS IN THE 40S THURSDAY NIGHT AND HIGHS ON FRIDAY BACK INTO THE 60S. BY LATE FRIDAY NIGHT ALL MODELS AGREE ON A WEAK COLD FRONT CROSSING THE AREA WITH ANOTHER HIGH PRESSURE BUILDING IN FROM THE WEST. THIS WILL CLEAR THE SKIES ACROSS THE AREA AS IT PUSHES THE TROUGH FARTHER OFF THE COAST. LOWS THURSDAY NIGHT WILL BE IN THE 40S WITH HIGH TEMPERATURES ON SATURDAY GETTING BACK TO AROUND NORMAL IN THE LOW 70S. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... AN AREA OF SFC LOW PRESSURE IS EXPECTED TO DEVELOP ON A STALLED BOUNDARY OFF THE SOUTHEAST COAST FRI NIGHT. THE LOW SHOULD TRACK NE WELL OFF THE CAROLINA COAST ON SAT. THIS FEATURE MAY BRING A FEW RAIN SHOWERS TO FAR SE VA/NE NC DURING THIS TIMEFRAME. MEANWHILE...AN UPPER LEVEL TROUGH OVER THE UPPER MIDWEST WILL SWING INTO THE ERN GREAT LAKES FRI NIGHT AND SKIRT ACROSS NRN VA ON SAT. A WEAK SFC LOW WILL BE ASSOCIATED WITH THIS FEATURE AND MAY BRING A BRIEF ROUND OF SHOWERS TO FAR NRN PORTIONS OF THE FA (INCLUDING THE MD/VA EASTERN SHORE) SAT AFTN/EARLY EVENING BEFORE MOVING OFFSHORE AND DISSIPATING. THE SFC LOW ASSOCIATED WITH THE GREAT LAKES TROUGH IS EXPECTED TO PHASE WITH THE AFOREMENTIONED COASTAL LOW SAT NIGHT...BUT THIS SHOULD OCCUR OVER NEW ENGLAND AND HAVE VERY LITTLE IMPACT TO THE MID ATLANTIC STATES. SFC HIGH PRESSURE BUILDS INTO THE REGION SUN...THEN SLIDES OFFSHORE BY SUN EVENING AS A RELATIVELY FLAT (WEST TO EAST ORIENTED) FRONTAL BOUNDARY SAGS DOWN INTO THE AREA MON NIGHT INTO TUE. WEAK SHORTWAVE ENERGY AND A SUBSEQUENT SFC LOW TRAVELING ALONG THIS BOUNDARY MAY BRING ANOTHER SHOT OF PRECIPITATION TO THE AREA ON MON/TUE. GFS PRECIP-GENERATION AND GENERAL MOVEMENT IS A BIT AGGRESSIVE VERSUS THE ECMWF...THEREFORE TRIED TO SPLIT THE DIFFERENCE WITH THE POP FORECAST AND LIMITED COVERAGE TO NO HIGHER THAN 40 PERCENT. TEMPERATURES ARE EXPECTED TO BE STRAIGHT-FORWARD SAT NIGHT THROUGH SUN NIGHT AS HIGH PRESSURE CROSSES THE REGION. EXPECT LOWS NEAR NORMAL BOTH NIGHTS IN THE 40S (LOWER 50S POSSIBLE IMMEDIATE SE VA/NE NC COASTS). HIGHS SAT/SUN RANGE FROM ROUGHLY 65 DEGREES FAR NE TO 70 DEGREES SW. AS THE FLAT FRONTAL BOUNDARY STARTS TO SAG INTO THE MID ATLANTIC STATES MON THROUGH TUE...THE TEMP FORECAST BECOMES TRICKY IN REGARD TO WHERE EXACTLY THE WARM SECTOR DEVELOPS. WITH PRECIP EXPECTED TO APPROACH THE AREA ON MON...INCREASING CIRRUS SHOULD KEEP HIGH TEMPS IN THE UPPER 60S WEST OF I-95 WITH WARMER TEMPS IN THE LOWER 70S EAST OF I-95 (MID-UPPER 60S MD/VA EASTERN SHORE). HIGHS TUE SHOULD BE IN THE LOWER 70S INLAND AND IN THE UPPER 60S NEAR THE IMMEDIATE CHES BAY AND ATLANTIC COASTS. LOW TEMPERATURES AREAWIDE ON MON/TUE NIGHT SHOULD ALSO BE WARM WITH READINGS IN THE 50S (OR ABOUT 10 DEGREES ABOVE NORMAL). && .AVIATION /19Z WEDNESDAY THROUGH MONDAY/... A MAINLY CLEAR SKY IS EXPECTED THROUGH EARLY THURSDAY MORNING. GUSTY N WINDS BECOME NE THIS AFTERNOON AND SLOWLY DIMINISH TOWARD EVENING. WINDS HAVE TENDED TO BE SLIGHTLY BACKED FROM MOS FORECASTS AND MADE ADJUSTMENTS ACCORDINGLY. NE WINDS MAY BE GUSTY ONCE AGAIN THURSDAY. STRATOCU CLOUDS WHICH COULD GO MVFR DEVELOP OVER SE SECTIONS THURSDAY MORNING ASSOCIATED WITH ONSHORE FLOW. OUTLOOK...AS HIGH PRESSURE STRENGTHENS OVER NEW ENGLAND AND THE CANADIAN MARITIMES...THE CHANCES FOR MVFR CONDS INCREASE THROUGH FRIDAY NIGHT...ESPECIALLY SE PORTIONS. THERE WILL ALSO BE A CHANCE FOR SHOWERS LATE FRIDAY AND FRIDAY NIGHT. A COLD FRONT MOVES THROUGH EARLY SATURDAY BUT THE TREND TOWARD ONSHORE FLOW WILL CONTINUE INTO EARLY NEXT WEEK. && .MARINE... UPDATE...REMAINING GALE WARNINGS HAVE BEEN CONVERTED INTO SCA FLAGS THROUGH AT LEAST EARLY THURSDAY MORNING. AS HIGH PRESSURE SLIDES ACROSS NEW ENGLAND TONIGHT INTO FRIDAY...WINDS TURN TO THE NE AND RESULT IN PERSISTENT SEAS OF 5 FT OR HIGHER. ANOTHER BUT WEAKER PUSH OF COLD AIR IS ANTICIPATED TO OCCUR OVERNIGHT INTO EARLY THURSDAY...WHICH WILL INCREASE WINDS INTO SCA THRESHOLDS DURING THIS TIME. IT IS LIKELY THAT SCA CONDITIONS DUE TO SEAS ABOVE 5 FT WILL CONTINUE BEYOND EARLY THURSDAY MORNING. WILL HAVE A FINAL DECISION MADE REGARDING HEADLINES BY THE AFTN FORECAST PACKAGE (ISSUED BY 4 PM TODAY). PREVIOUS DISCUSSION...HI PRES SLIDES NE ACRS NEW ENGLAND AND INTO THE CANADIAN MARITIMES TNGT INTO FRI...AS A WEAK CSTL TROF DEVELOPS OFF THE SE AND MID ATLC CST. THIS WILL RESULT IN A PROLONGED PERIOD OF NE WINDS AND ELEVATED SEAS THRU THE END OF THE WEEK. && .CLIMATE... RECORD LOW MAXIMUM TEMPERATURES TODAY 4/16: RIC...45 (1929) ORF...46 (1935) SBY...45 (1935) ECG...52 (1962 & 1952) RECORD LOWS THU 4/17: RIC...31 (1949) ORF...34 (1875) SBY...26 (2008) && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...FREEZE WARNING FROM 2 AM TO 9 AM EDT THURSDAY FOR MDZ021>023. NC...FREEZE WARNING FROM 2 AM TO 9 AM EDT THURSDAY FOR NCZ012. VA...FREEZE WARNING FROM 2 AM TO 9 AM EDT THURSDAY FOR VAZ048-049- 060>083-085-087>089-092. MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT FRIDAY FOR ANZ633-650-652- 654-656-658. SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO 1 PM EDT THURSDAY FOR ANZ635>637. SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT THURSDAY NIGHT FOR ANZ632-634. SMALL CRAFT ADVISORY UNTIL 1 PM EDT THURSDAY FOR ANZ630-631- 638. && $$ SYNOPSIS...JAB NEAR TERM...JAB SHORT TERM...JAB LONG TERM...BMD AVIATION...LSA MARINE...BMD/TMG CLIMATE...
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1243 PM CDT WED APR 16 2014 .UPDATE... ISSUED AT 1240 PM CDT WED APR 16 2014 TEMPS ARE WARMING A BIT MORE IN THE NORTHERN VALLEY WITH SUNSHINE...SO WILL INCREASE TEMPS SOME HERE. THE REST OF THE FORECAST IS IN VERY GOOD SHAPE...WITH LITTLE ADDITIONAL CHANGES PLANNED. && .SHORT TERM...(TODAY THROUGH THURSDAY) ISSUED AT 331 AM CDT WED APR 16 2014 SNOW CHANCES TODAY WILL BE THE PRIMARY FORECAST HEADACHE FOR THE PERIOD. SNOW HAS STARTED TO DEVELOP ALONG A MID LEVEL FRONTOGENESIS BAND FROM NORTH CENTRAL ND DOWN TOWARDS FARGO AND FERGUS FALLS. THINK THE RAP SEEMS TO HAVE A DECENT HANDLE ON THE BAND...AND THINK THIS WILL STICK AROUND AND DROP AN INCH OR TWO BEFORE DIMINISHING AS THE SFC LOW WRAPS UP AND FRONTOGENESIS STRENGTHENS FURTHER SOUTH. FOR LATER TODAY... THE SHORTWAVE CURRENTLY MOVING INTO THE WESTERN PLAINS WILL QUICKLY PROGRESS EASTWARD INTO SOUTHERN MN. SFC LOW PRESSURE WILL MOVE FROM SOUTHERN SD TO THE IA/MN BORDER...WITH OUR SOUTHERN COUNTIES ON THE NORTHERN EDGE OF THE DEFORMATION BAND. THE GEM KEEPS MOST OF THE SNOW FURTHER TO THE SOUTH...BUT THE OTHER DETERMINISTIC MODELS STILL BRING SOME 3 TO 6 INCH AMOUNTS TO OUR SOUTHEASTERN COUNTIES. WILL CONTINUE TO KEEP THE STATUS QUO AND KEEP HIGH POPS AND THE ADVISORY GOING FOR OUR SOUTHEASTERN COUNTIES. MAIN CHANGE FOR TODAY WAS TO ADD IN A BRIEF PATCHY BLOWING SNOW MENTION FOR WHEN PRECIP IS FALLING IN OUR SOUTHEAST...AS NORTHEASTERLY WINDS WILL BE QUITE STRONG TODAY AT TIMES. THE SNOW WILL RAPIDLY TAPER OFF THIS EVENING AS THE MAIN SHORTWAVE TAKES OFF INTO WI AND HIGH PRESSURE BUILDS DOWN INTO THE NORTHERN PLAINS. SKIES WILL BEGIN TO CLEAR OUT ALTHOUGH THE WINDS WILL STAY UP AND KEEP US FROM COMPLETELY BOTTOMING OUT...WITH LOWS STAYING IN THE TEENS TO LOW 20S. SFC HIGH PRESSURE WILL CONTINUE INTO THURSDAY WITH DECREASING WINDS AND MOSTLY SUNNY SKIES. THE AIR MASS WILL STILL BE PRETTY COLD HOWEVER...SO KEPT TEMPS IN THE 30S TO AROUND 40 DEGREES. .LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY) ISSUED AT 331 AM CDT WED APR 16 2014 THURSDAY NIGHT THROUGH FRIDAY NIGHT...NORTHWESTERLY FLOW ALOFT BEGINS TO SHIFT AS A RIDGE BRIEFLY BUILDS IN AHEAD OF THE NEXT SHORTWAVE MOVING INTO SASK. A TROUGH OF LOW PRESSURE DEVELOPING OVER THE NORTHERN ROCKIES WILL BEGIN TO SHIFT WINDS BACK TO THE SOUTHEAST. MODELS HAVE A WEAK REINFORCING SHORTWAVE MOVING BY THURSDAY NIGHT BUT THINK THAT ANYTHING IT PRODUCES WILL STAY TO OUR SOUTH AND WEST. FRIDAY WILL BE A BIT WARMER THAN EARLIER IN THE WEEK BUT STILL BELOW AVERAGE WITH HIGHS IN THE 40S. MODELS DIVERGE ON BRINGING THE NEXT ROUND OF PRECIP THROUGH IN THE WARM AIR ADVECTION AHEAD OF THE NEXT SHORTWAVE. THE ECMWF AND PARTICULARLY THE GEM HAVE PRECIP MOVING QUICKLY EASTWARD FRIDAY NIGHT...WHILE THE GFS AND NAM ARE MUCH SLOWER. WILL GO WITH A BIT OF A BLEND...BUT GIVEN THE WAY SATURATION HAS TAKEN ITS TIME...LEANED A BIT TOWARDS THE SLOWER SOLUTION. JUST KEPT SOME SLIGHT POPS IN THE EAST WITH NEAR 40 PERCENT IN THE WEST FOR NOW. SATURDAY THROUGH TUESDAY NIGHT...00 UTC GFS/ECMWF ARE IN FAIR AGREEMENT. ON SATURDAY...A NEGATIVELY TILTED SHORT-WAVE WILL ROTATE THROUGH THE NORTHERN PLAINS BRINGING WARM AIR ADVECTION-INDUCED PRECIP ACROSS THE FORECAST AREA. FLOW ALOFT THEREAFTER THROUGH TUESDAY BECOMES MORE ZONAL WITH A SLIGHT PROPENSITY FOR SHORT-WAVE RIDGING. SUNDAY/MONDAY LOOK DRY...BUT PRECIP CHANCES WILL INCREASE AGAIN LATE TUESDAY INTO WEDNESDAY AS A DEEP TROUGH TAKES SHAPE ACROSS THE GREAT BASIN TURNING THE FLOW ACROSS THE NATION/S MID-SECTION TO THE SOUTHWEST. WITH THE EXCEPTION OF A RAIN/SNOW MIX AT NIGHT... MAJORITY OF PRECIP SHOULD FALL AS RAIN THROUGH THE PERIOD. AFTER ONE MORE RELATIVELY COOLER DAY ON SATURDAY (HIGHS FROM THE MID 40S TO NEAR 50 DEGREES)...MID-LEVEL THERMAL RIDGE PUSHES EAST ALLOWING TEMPERATURES TO CLIMB INTO THE 50S AND 60S SUNDAY INTO EARLY NEXT WEEK. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 1240 PM CDT WED APR 16 2014 VFR THIS AFTN AT ALL TAF SITES WITH THE EXCEPTION OF FAR WHERE CIGS HAVE BEEN SPORADICALLY DOWN INTO MVFR RANGE. OTHERWISE CIGS WILL REMAIN VFR WITH SOME GUIDANCE LOWERING CIGS OVERNIGHT. WITH DRY EASTERLY AIR TURNING TO THE NORTH OVERNIGHT AND NO STRATUS DECK TO THE NORTH TO ADVECT IN...EXPECTING VFR CONDITIONS TO PERSIST. GUSTY ENE WINDS TO DIMINISH WITH SUNDOWN THIS EVENING. && .HYDROLOGY... ISSUED AT 1240 PM CDT WED APR 16 2014 THE COLD NIGHTS...COOL DAYTIME HIGHS AND DIMINISHING SNOW PACK HAVE VIRTUALLY ENDED RUNOFF. WE ARE DOWN TO SIX FORECAST POINTS AT OR ABOVE FLOOD STAGE. THESE INCLUDE THE NORTHERN THIRD OF THE RED RIVER OF THE NORTH AS WELL AS ALVARADO ON THE SNAKE RIVER AND THE HALLOCK ON THE TWO RIVERS. THE ONLY LOCATIONS STILL RISING ARE DRAYTON AND PEMBINA ON THE RED RIVER. COLDER THAN AVERAGE WEATHER WILL PERSIST THROUGH FRIDAY WITH MODERATION IN STORE FOR THE WEEKEND. TODAY`S STORM SYSTEM WILL MAINLY AFFECT PORTIONS OF WEST CENTRAL MINNESOTA WITH UP TO ONE THIRD INCH OF LIQUID EQUIVALENT PRECIPITATION...AND LITTLE OR NO PRECIPITATION OVER THE NORTHERN RED RIVER VALLEY. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...WINTER WEATHER ADVISORY UNTIL 6 PM CDT THIS EVENING FOR MNZ030>032-040. && $$ UPDATE...DK SHORT TERM...JR LONG TERM...ROGERS AVIATION...DK HYDROLOGY...WJB
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1205 PM CDT WED APR 16 2014 .SHORT TERM...(TODAY THROUGH TONIGHT) ISSUED AT 411 AM CDT WED APR 16 2014 MAIN CONCERN DEALING WITH STRONG LOW PRESSURE AND ITS IMPACT ON THE AREA...INCLUDING ACCUMULATING SNOW ACROSS NORTHERN WI AND GUSTY WINDS ELSEWHERE. SURFACE MAP EARLY THIS MORNING HAS AN AREA OF DEEPENING LOW PRESSURE OVER SOUTHERN SD WITH A WARM FRONT EXTENDING EASTWARD THROUGH CENTRAL IA. BROAD SCALE ISENTROPIC LIFT AND STRENGTHENING MID-LEVEL FRONTOGENESIS ACROSS CENTRAL MN INTO NORTHWEST WI STARTING TO FOCUS SOME -SN ACROSS THAT AREA. ELSEWHERE ACROSS THE AREA...SKIES WERE CLOUDY WITH TEMPERATURES RANGING FROM THE UPPER 20S TO LOWER 30S. MODELS COMING INTO BETTER AGREEMENT NOW WITH HANDLING OF PRECIPITATION ACROSS THE AREA TODAY THROUGH TONIGHT. LOOKING LIKE MODELS ARE TRENDING A FARTHER NORTH PUSH WITH PRECIPITATION ACROSS NORTHERN WI...IN THE FORM OF SNOW THIS MORNING...AND RAIN MIXING WITH SNOW BY THIS AFTERNOON. HAVE CONFINED HIGHER POPS A BIT FARTHER NORTH FOR TODAY...BUT A FEW MODELS INCLUDING THE RAP AND LATEST SREF SHOWING THE POSSIBILITY OF PRECIPITATION TOTALLY PUSHING NORTH OUT OF OUR AREA THIS AFTERNOON. 16.00Z DETERMINISTIC NAM/GFS/EC ALL SHOWING PRECIPITATION HANGING MAINLY ALONG AND NORTH OF THE I-94 CORRIDOR WITH ACCUMULATING SNOW THROUGH THIS MORNING MAINLY NORTH OF HIGHWAY 29 IN NORTHERN CLARK COUNTY. CURRENT THINKING WITH RADAR TREND AND THE 00Z MODELS IN MIND IS FOR SNOW THIS MORNING ACROSS CLARK/TAYLOR WITH 1-3 INCHES THROUGH LATE MORNING MAINLY NORTH OF HIGHWAY 29. WITH THIS IN MIND...WILL HANG ONTO THE WINTER WEATHER ADVISORY FOR NOW ACROSS CLARK AND TAYLOR...BUT STARTING TO HAVE MY DOUBTS WHETHER CARRYING IT PAST 18Z GIVEN WHAT THE RAP/SREF MODELS ARE SAYING. THIS IS OBVIOUSLY A QUICKLY CHANGING SITUATION AND WILL HAVE TO BE MONITORED CLOSELY BY THE DAY SHIFT TODAY. OTHER CONCERN FOR TODAY WILL BE INCREASING/GUSTY SOUTH WINDS MAINLY ALONG AND SOUTH OF THE I-90 CORRIDOR TODAY AHEAD OF THE DEEP LOW PRESSURE SYSTEM MOVING EAST ALONG THE IA/MN BORDER THIS AFTERNOON. WILL SEE SUSTAINED WINDS OF 20-30 MPH WITH SOME GUST AROUND 40 MPH. RIGHT NOW...WINDS LOOK BORDERLINE FOR A WIND ADVISORY...BUT WILL LET THE DAYSHIFT MONITOR THIS AS WELL. OTHERWISE...TEMPERATURES ACROSS THE AREA WILL VARY FROM AROUND 40 ACROSS NORTH CENTRAL WI...TO THE 50S ALONG/SOUTH OF I-90. FOR TONIGHT...THE LOW PRESSURE AREA WILL LIFT NORTHEAST INTO NORTHERN WI WITH DEFORMATION RAIN/SNOW...CHANGING TO ALL SNOW LOOKING LIKELY ACROSS EASTERN MN INTO NORTHERN WI. LOOKS LIKE THE SOUTHERN PERIPHERY OF OF THE DEFORMATION SNOW CLIPS CLARK AND TAYLOR WITH ACCUMULATING SNOW AGAIN TONIGHT...WITH AMOUNTS OF 1-2 INCHES. MEANWHILE...THERE ARE A FEW WRF MODELS SHOWING A BAND OF SHOWERS FORMING ALONG THE COLD FRONT OF THE LOW SWINGING ACROSS SOUTHERN PARTS OF THE AREA DURING THIS EVENING. PUSHED POPS INTO LIKELY CATEGORY BASED ON THIS SIGNAL. APPEARS PRECIPITATION MIXES AND CHANGES TO ALL SNOW THROUGH THE NIGHT ACROSS THE REST OF THE AREA WITH THE BULK OF THE PRECIPITATION LIFTING NORTHEAST OF I-94 BY MORNING. THEREFORE...LITTLE IF ANY SNOW ACCUMULATION EXPECTED SOUTHWEST OF I-94 THROUGH THE NIGHT. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 411 AM CDT WED APR 16 2014 THERE MAY BE SOME LINGERING LIGHT SNOW WITH MINIMAL ACCUMULATION THURSDAY MORNING NORTHEAST OF I-94. REST OF THE DAY WILL BE MOSTLY CLOUDY...AND COOL WITH HIGHS ONLY MAKING IT INTO THE 40 TO 50 DEGREE RANGE. A COLD NIGHT THEN SETS UP THURSDAY NIGHT AS HIGH PRESSURE NOSES INTO THE AREA WITH LOWS DROPPING OFF INTO THE 20S. A MID-LEVEL SHORTWAVE TROUGH/PV-ADVECTION ROTATES THROUGH SOUTHERN MN/IA ON FRIDAY. THIS GIVES PORTIONS OF NORTHEAST IA/SOUTHEAST MN A SLIGHT CHANCE OF EARLY MORNING LIGHT SNOW AND DAYTIME RAIN. OTHERWISE...PLAN ON HIGHS IN THE AGAIN IN THE 40S TO A FEW LOWER 50S ACROSS FAR NORTHEAST IA/SOUTHWEST WI. A CHANCE OF RAIN ENTERS THE PICTURE FOR SATURDAY AFTERNOON THROUGH SUNDAY NIGHT AS A MID-LEVEL TROUGH AND WEAK SURFACE COLD FRONT PUSH SLOWLY EAST ACROSS THE AREA. LOOK FOR HIGHS SATURDAY AND SUNDAY IN THE 50S. THERE MAY BE A FEW LINGERING SHOWER ACROSS CENTRAL WI ON MONDAY BUT THE REST OF THE AREA WILL SEE MOSTLY SUNNY SKIES AS MID/UPPER LEVEL RIDGE BUILDS INTO THE AREA. THIS WARMS HIGHS INTO THE UPPER 50S TO THE LOWER 60S. LOOK FOR THIS RIDGE TO PERSIST INTO TUESDAY FOR MOSTLY SUNNY CONDITIONS AND HIGHS TOPPING OFF AGAIN IN THE UPPER 50S TO LOWER 60S...OR RIGHT AROUND NORMAL LEVELS. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 1205 PM CDT WED APR 16 2014 MIXING WILL CONTINUE HIGHER WIND GUSTS THROUGH THE AFTERNOON...STAYING SOUTHEASTERLY BEFORE A COLD FRONT SWEEPS IN OVERNIGHT. WINDS BECOME WESTERLY POST THE FRONT...WITH THE PRESSURE GRADIENT STAYING FAIRLY TIGHT THROUGH THU MORNING. CIGS WILL STAY VFR AHEAD OF THE FRONT...WITH BUFKIT SOUNDINGS AND RH FIELDS POINTING TO A DROP INTO MVFR - POTENTIALLY IFR - AFTER THE FRONT MOVES THROUGH. MOST OF THE PCPN ASSOCIATED WITH THIS SYSTEM WILL FALL TO THE NORTH...WITH SIGNIFICANT SNOW ACCUMULATIONS. THAT SAID...MESO MODELS CONTINUE TO SUGGEST SOME LIGHT PCPN ALONG AND BEHIND THE FRONT...WHICH MATCHES WITH THE LATEST RADAR TRENDS. TEMP PROFILES SUPPORT MOSTLY RAIN AT THIS TIME. SOUNDINGS ARE SUGGESTING A LOSS OF ICE AS THE FRONT WORKS ACROSS WESTERN WI OVERNIGHT...WHICH WOULD RESULT IN DRIZZLE/VERY LIGHT RAIN. FREEZING PCPN WOULD BE A CONCERN IF GROUND TEMPS ARE COLD ENOUGH. CONFIDENCE NOT HIGH ENOUGH THAT THIS WILL OCCUR...SO WILL LEAVE OUT OF THE FORECAST FOR NOW. WITH THE LOW MOVING INTO EASTERN WI BY 18Z THU...EXPECT SOME CLEARING FROM WEST-EAST OF THE CLOUD COVER. GUIDANCE WOULD KEEP BKN/OVC SKIES...BUT SOUNDINGS POINT TO MIXING OUT OF THE LOW CIGS. GOING TO TREND THE FORECAST THIS WAY. && .HYDROLOGY... ISSUED AT 411 AM CDT WED APR 16 2014 RIVERS REMAIN AT ELEVATED LEVELS FROM HEAVIER RAINFALL THIS PAST WEEKEND. FLOOD WARNINGS REMAIN IN EFFECT FOR THE SOUTHERN REACHES OF THE KICKAPOO RIVER AT GAYS MILLS AND STEUBEN. A FLOOD WARNING IS ALSO IN EFFECT FOR THE MISSISSIPPI AT WABASHA AND MCGREGOR. SEE WWW.WEATHER.GOV/AHPS2/INDEX.PHP?WFO=ARX FOR LATEST RIVER LEVELS AND FORECASTS. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...WINTER WEATHER ADVISORY UNTIL 7 AM CDT THURSDAY FOR WIZ017-029. MN...NONE. IA...NONE. && $$ SHORT TERM...DAS LONG TERM....DAS AVIATION.....RIECK HYDROLOGY....DAS