Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 01/11/14


AREA FORECAST DISCUSSION
NWS SACRAMENTO CA
935 AM PST Thu Jan 9 2014 .Synopsis... A weak warm front may bring a few light showers to far northern Shasta County through this afternoon. Dry conditions are expected elsewhere with milder temperatures. Building high pressure will bring clearing skies with daytime highs back to several degrees above normal through Friday. Another frontal system will bring a threat of light precipitation to most of the forecast area on Saturday with daytime highs dropping to near normal. Rebuilding high pressure will bring a return of drier conditions and warming temperatures on Sunday, with daytime highs around 10 degrees above normal through next week. && .Discussion... A weak upper level shortwave and surface front brushed through the far northern part of the state overnight through this morning. This has generally brought just a few hundredths of an inch of rain inland to the northern and Coastal mountains, though locations on the coast saw up to an inch. Redding saw a hundredth of an inch, with a spotter in Burney reporting 0.03 in. Chester had 0.04 in of rain, with a brief period of freezing rain. Radar shows few returns currently, mainly north of Shasta County. Short term meso WRF and HRRR models show shower potential trending down and have lowered pops accordingly. Will keep just a slight chance of a few showers will continue through the afternoon hours over the far northern portion of Shasta County before the upper trough exits completely. Patchy fog and mist have developed this morning through portions of the Valley, along with some patches of low stratus clouds. The clouds should clear by late morning with linger have diminishing by late afternoon. Plan to increase highs today a couple of degrees with a somewhat warmer start and afternoon sunshine. Have decided to go a little lower than some of the guidance, though, due to the possibility of clouds lingering a bit longer than expected. Forecast update will be out shortly. Another Pacific storm system is forecast to move onshore on Saturday bringing clouds and cooler temperatures and a threat of light precipitation to most of the forecast area. Models have been fairly consistent on this feature for the last several runs. The latest 12z GFS even digs this system a little farther south than the 06z run with increased rain and snow amounts. EK .Extended Discussion (Monday through Thursday) The extended models are all in agreement that a strong ridging pattern starting on Monday will bring another period of above normal temperatures and dry weather. Locally breezy winds are likely to develop late Sunday into Monday night with breezy periods again on Tuesday. Expect enhanced northerly flow in the valley, generally along the western half of the Sacramento Valley. In addition, Northeast to East winds will be enhanced along the Western Sierra Slopes. For Wednesday into the weekend, the upper level ridge axis will move overhead which will bring lighter winds to our region. JBB && .Aviation... Areas of MVFR/IFR cigs/vsbys mainly in the Northern San Joaquin Valley and isolated in the Sac Valley thru 20z as weak wx system exits the region. Conditions expected to improve to VFR during the afternoon. Strong ridge prevails over the region tonite and FRI with VFR flight after possible morning local MVFR/IFR conditions in stratus and fog in the interior valley. Light Nly wind flow at the surface. && .STO Watches/Warnings/Advisories... None. && $$
AREA FORECAST DISCUSSION
NWS ALBANY NY
611 PM EST FRI JAN 10 2014 .SYNOPSIS... HIGH PRESSURE WILL CONTINUE TO SHIFT EASTWARD AND OFFSHORE OVERNIGHT...AS A STRENGTHENING STORM SYSTEM MOVES ACROSS THE WESTERN GREAT LAKES AND SOUTHEAST CANADA LATE TONIGHT INTO SATURDAY. MILDER AIR WILL BE USHERED INTO THE REGION AS THE SYSTEM AND ITS ASSOCIATED FRONTAL SYSTEM APPROACHES. SOME FREEZING RAIN IS POSSIBLE LATE TONIGHT INTO EARLY SATURDAY MORNING...THEN RAIN IS EXPECTED INTO SATURDAY NIGHT...WITH SOME LOCALLY HEAVY RAIN POSSIBLE DURING THE AFTERNOON AND EVENING HOURS. IMPROVING CONDITIONS...ALONG WITH ABOVE NORMAL TEMPERATURES ARE EXPECTED FOR SUNDAY. && .NEAR TERM /UNTIL 6 AM SATURDAY MORNING/... FREEZING RAIN ADVISORIES ISSUED FOR THE OVERNIGHT HOURS... FLOOD WATCH REMAIN IN EFFECT FOR SAT AFTN THROUGH SUN AFTN... NOT MUCH TO ADD TO WHAT THE PREVIOUS DISCUSSION PROVIDES...AS VERY LIGHT PRECIPITATION INCHES NORTH TOWARD THE MID HUDSON VALLEY AND NW CT. TEMPERATURES AROUND FREEZING TO JUST BELOW FREEZING IN MOST PLACES...SO FREEZING RAIN ADVISORY WILL CONTINUE AS THE PRECIPITATION MOVES IN. JUST SOME MINOR CHANGES TO THE FORECAST THROUGH THIS EVENING BASED ON CURRENT OBSERVATIONS AND TRENDS. PREVIOUS DISCUSSION BELOW... SOME BREAKS IN THE CLOUDS CONTINUE ACROSS PORTIONS OF THE GREATER CAPITAL REGION...WITH MOSTLY CLOUDY SKIES ELSEWHERE. TEMPS HAVE RISEN INTO THE LOWER 30S FOR MOST AREAS SOUTH AND EAST OF THE CAPITAL REGION...WITH MAINLY UPPER 20S TO LOWER 30S TO THE NORTH AND WEST. THE AFOREMENTIONED PARTIAL CLEARING APPEARS TO HAVE BEEN LARGELY DUE TO SOME SUBSIDENCE IN THE WAKE OF THE SHORTWAVE...WHICH PASSED EAST ACROSS THE REGION EARLIER TODAY...AND ALSO DUE TO SOME DOWNSLOPING OFF THE CATSKILLS DUE TO A STRENGTHENING SOUTHWEST FLOW AROUND 4000-6000 FT AGL. LOOKING TO OUR SOUTH...PRECIPITATION CONTINUES TO DEVELOP ACROSS PORTIONS OF THE MID ATLANTIC STATES...WHERE LOW/MID LEVEL ISENTROPIC LIFT AND THETA-E ADVECTION INCREASES. SHORT-TERM MODELS...SUCH AS THE RAP13 AND HRRR SUGGEST THAT THIS AREA OF FORCING TRANSLATES NORTH NORTHEAST INTO SOUTHERN PORTIONS OF THE REGION BETWEEN 10 PM AND MIDNIGHT...AND GENERALLY BETWEEN MIDNIGHT AND 4 AM FURTHER N AND W. THERMAL PROFILES SUGGEST HYDROMETEORS SHOULD BE PRIMARILY LIQUID...ALTHOUGH SOME SLEET COULD BE MIXED IN ACROSS NORTHERN AREAS INITIALLY. SFC TEMPS...WHICH ARE CURRENTLY JUST BARELY ABOVE FREEZING...ARE EXPECTED TO FALL AT LEAST A FEW DEGREES THIS EVENING...BEFORE LEVELING OFF...AND EVENTUALLY RISING AFTER MIDNIGHT. HOWEVER...IT APPEARS THAT SOME LIGHT PRECIPITATION WILL DEVELOP BEFORE SFC TEMPS RISE ABOVE FREEZING. IN ADDITION...EVEN IF SFC TEMPS ARE AROUND OR A BIT ABOVE FREEZING...THE GROUND REMAINS VERY COLD FROM THE RECENT COLD SPELL...SO UNTREATED SURFACES MAY ACCRETE A LIGHT GLAZE OF ICE...EVEN WITH TEMPS SLIGHTLY ABOVE FREEZING. THEREFORE...A FREEZING RAIN ADVISORY HAS BEEN ISSUED AREAWIDE...ALTHOUGH THE ENDING TIMES OF THE ADVISORY ARE EARLIER ACROSS SOUTHERN AREAS...AND LATER...MID MORNING...FOR NORTHERN AREAS...WHERE SUBFREEZING SFC TEMPS MAY LINGER IN SHELTERED VALLEY AREAS. TOTAL ICE ACCRETION IS NOT EXPECTED TO BE MUCH...GENERALLY UNDER ONE TENTH OF AN INCH...BUT MAY STILL HAVE HIGH IMPACTS ON TRAVEL DUE TO THE FROZEN GROUND. && .SHORT TERM /6 AM SATURDAY MORNING THROUGH MONDAY NIGHT/... SATURDAY...AS MENTIONED...SOME NORTHERN AREAS...PARTICULARLY ACROSS PORTIONS OF THE LAKE GEORGE REGION...AND SOUTHWEST ADIRONDACKS...AND POSSIBLY SOUTHEAST VT MAY REMAIN NEAR THE FREEZING MARK THROUGH 9 AM EST SAT AM...WHERE POCKETS OF FREEZING RAIN MAY LINGER. OTHERWISE...EXPECT PERIODS OF RAIN OR DRIZZLE THROUGH MUCH OF THE DAY. AREAS OF FOG...SOME LOCALLY QUITE DENSE...WILL ALSO LIKELY OCCUR AS THE INCREASINGLY MILD AND MOIST AIR DRIFTS ACROSS THE VERY COLD GROUND. IT ALSO MAY BECOME QUITE BREEZY/WINDY ACROSS HIGHER ELEVATIONS OF THE SOUTHERN GREEN MTNS/BERKSHIRES AND TACONICS...WHERE SOUTH TO SOUTHEAST WINDS MAY GUST UP TO 35-45 MPH AT TIMES. IN VALLEY AREAS...NOT EXPECTING AS MUCH WIND DUE TO A RATHER STRONG LOW LEVEL INVERSION...BUT SHOULD THE LOW LEVEL INVERSION BE WEAKER THAN CURRENTLY FORECAST...SOME STRONGER WINDS COULD MIX WITHIN NORTH/SOUTH ORIENTED VALLEYS. THEN...AS THE COLD FRONT APPROACHES FROM THE WEST LATER IN THE DAY...A BAND OF MODERATE TO LOCALLY HEAVY RAINFALL IS EXPECTED TO DEVELOP AND MOVE FROM W TO E. THIS BAND OF RAIN COULD EVOLVE INTO A NARROW COLD FRONTAL RAINBAND...AND PRODUCE LOCALLY VERY HEAVY RAINFALL...AND STRONG WIND GUSTS...AND RADAR TRENDS WILL HAVE TO BE MONITORED. SAT NT...THE AFOREMENTIONED FRONTAL RAINBAND SHOULD CONTINUE MOVING EAST ACROSS THE REGION IN THE EVENING. BEHIND IT...A BRIEF PERIOD OF LINGERING SHOWERS OR RAIN IS POSSIBLE...BEFORE THE RAIN ENDS FROM W TO E IN MOST AREAS BY MIDNIGHT. HOWEVER...SOME SHOWERS OF RAIN...AND EVENTUALLY SNOW SHOULD DEVELOP ACROSS PORTIONS OF THE SOUTHERN ADIRONDACKS LATER AT NIGHT WITH MINOR ACCUMS. WEST WINDS WILL ALSO INCREASE LATER AT NIGHT...ESP WITHIN THE MOHAWK RIVER VALLEY/CAPITAL REGION/BERKSHIRES. SUNDAY...A BRISK WEST WIND SHOULD CONTINUE THROUGH EARLY AFTERNOON...WITH SOME GUSTS OF 30-40 MPH POSSIBLE...ESP DOWN THE MOHAWK VALLEY AND INTO THE CAPITAL REGION AND BERKSHIRES. HOWEVER...DESPITE GUSTY WINDS...TEMPS WILL ACTUALLY BE ABOVE NORMAL GIVEN THE PACIFIC ORIGINS OF THE INCOMING AIRMASS. SOME SHOWERS OF RAIN/SNOW WILL BE POSSIBLE ACROSS NORTHERN AREAS...ESP EARLY...ALONG WITH PARTLY TO MOSTLY CLOUDY SKIES. HOWEVER...SKIES SHOULD CLEAR FROM SOUTH TO NORTH IN THE AFTERNOON. EXPECT TEMPS TO REACH THE LOWER/MID 40S IN VALLEYS...AND MID 30S TO AROUND 40 ACROSS HIGHER ELEVATIONS. SUN NT-MON...GENERALLY FAIR...WITH ABOVE NORMAL TEMPS. EXPECT MINS TO FALL INTO THE 20S...AND MON MAXES REACHING THE LOWER/MID 40S IN MOST AREAS. SOME CLOUDS WILL INCREASE LATE MONDAY IN ADVANCE OF THE NEXT SYSTEM. && .LONG TERM /TUESDAY THROUGH FRIDAY/... THE LONG TERM PERIOD WILL BE CHARACTERIZED BY SLIGHTLY ABOVE NORMAL TEMPERATURES AND QUICK MOVING STORM SYSTEMS BRINGING CHANCES FOR RAIN/SNOW SHOWERS. AT THE START OF THE LONG TERM PERIOD...A LARGE AMPLITUDE UPPER-LEVEL PATTERN WILL BE IN PLACE ACROSS MUCH OF THE CONUS...WITH A LONGWAVE TROUGH ACROSS THE CENTRAL CONUS AND MEAN RIDGING/SOUTHWEST FLOW ACROSS THE EASTERN THIRD OF THE NATION. AT THE SURFACE...AN AREA OF LOW PRESSURE WILL BE TAKING SHAPE ACROSS THE LOWER MISSISSIPPI RIVER VALLEY. THERE CONTINUES TO BE SIGNIFICANT UNCERTAINTY REGARDING THE EVOLUTION OF THIS SYSTEM...PARTICULARLY IN THE EVOLUTION OF A PAIR OF DISTURBANCES ASSOCIATED WITH THE NORTHERN AND SOUTHERN STREAMS. THE 12Z GFS...GGEM AND MOST GEFS MEMBERS CONTINUE TO FAVOR A MORE PROGRESSIVE SOLUTION...WITH THE NORTHERN STREAM DOMINATING AND ALLOWING A PROGRESSIVE TROUGH AND WEAK SURFACE LOW TO MOVE THROUGH THE REGION TUESDAY WITH CHANCES FOR RAIN/SNOW SHOWERS. MEANWHILE...THE 12Z ECMWF CONTINUES TO BE SLOWER FAVORING A SOUTHERN STREAM DOMINATED SURFACE LOW THAT QUICKLY RACES UP THE EASTERN SEABOARD AND THEN PHASES WITH THE NORTHERN STREAM...ALLOWING FOR A RATHER DEEP AND DYNAMIC SYSTEM TO PRODUCE WIDESPREAD PRECIPITATION ACROSS THE REGION. GIVEN LONG RANGE GUIDANCE DIFFICULTY IN HANDLING LARGE AMPLITUDE PATTERNS IN THE EXTENDED...HAVE GONE WITH CHANCE POPS FOR TUESDAY...SIDING CLOSE TO WPC GUIDANCE WHICH FAVORS A LOW PRESSURE SYSTEM TRACKING ACROSS THE REGION WITH RAIN/SNOW SHOWERS MONDAY NIGHT TRANSITIONING TO PRIMARILY RAIN DURING THE DAY TUESDAY. THIS SYSTEM QUICKLY EXITS TUESDAY NIGHT...LEAVING SCATTERED SNOW SHOWERS AND A BROAD UPPER-LEVEL TROUGH IN ITS WAKE. A SERIES OF DISTURBANCES WILL MOVE THROUGH THIS TROUGH LEADING TO ADDITIONAL CHANCES FOR RAIN/SNOW SHOWERS WEDNESDAY BEFORE TRANSITIONING TO ALL SNOW FOR WEDNESDAY NIGHT. BOTH THE 12Z GFS AND ECMWF HINT AT THE POTENTIAL FOR COASTAL LOW DEVELOPMENT WEDNESDAY NIGHT INTO THURSDAY...WHICH COULD ENHANCE SNOWFALL POTENTIAL ESPECIALLY EAST OF THE CAPITAL DISTRICT. WILL CONTINUE TO GO WITH CHANCE POPS THROUGHOUT THIS TIMEFRAME AS MODEL UNCERTAINTY REMAINS HIGH. WEAK HIGH PRESSURE WILL BUILD ACROSS THE REGION FOR THURSDAY...BRINGING DRY WEATHER AND CLEARING SKIES TO MUCH OF THE REGION BEFORE ANOTHER UPPER-LEVEL DISTURBANCE DIVING OUT OF THE GREAT LAKES REGION APPROACHES THE REGION TO END THE WORK WEEK. MODEL GUIDANCE CONTINUES TO INDICATE THAT THIS SYSTEM WILL HAVE LITTLE MOISTURE TO WORK WITH...HOWEVER IT WILL BRING A REINFORCING SHOT OF COLD AIR TO THE REGION FOR THE WEEKEND. HIGHS WILL INITIALLY RANGE FROM THE UPPER 30S TO UPPER 40S TUESDAY...BEFORE COOLING SLIGHTLY TO BETWEEN THE UPPER 20S AND MID 30S FOR THE REMAINDER OF THE WORK WEEK. LOWS WILL INITIALLY BE IN THE LOW TO MID 30S ACROSS THE REGION MONDAY AND TUESDAY NIGHT...BEFORE COOLING AND SETTLING INTO THE UPPER TEENS TO MID 20S FOR THE REMAINDER OF THE WORK WEEK. && .AVIATION /00Z SATURDAY THROUGH WEDNESDAY/... A WEAK WARM FRONT WILL BRING THE CHANCE OF PRECIPITATION TO ALL THE TAF SITES TONIGHT. TEMPERATURES WILL SUPPORT A WINTRY MIX ESPECIALLY AT KPSF/KALB/KGFL FROM 03Z TO 09Z SATURDAY AT KALB/KPSF EXTENDING TO AS LATE AS 12Z-15Z SATURDAY AT KPSF AND KGFL. PRECIPITATION TYPE WILL CHANGE TO ALL RAIN BETWEEN 09Z-15Z SATURDAY AT ALL TAF SITES. THE MAIN COLD FRONT TO OUR WEST WILL NOT BE MOVING INTO THE REGION UNTO AFTER THE END OF THE TAF FORECAST PERIOD AFTER 00Z SUNDAY. VFR/MVFR CONDITIONS WILL TREND TOWARD BORDERLINE IFR CONDITIONS TONIGHT AND HOLD NEAR IFR THROUGH THE DAY TOMORROW WITH THE PRECIPITATION IN THE REGION. WINDS WILL BE SOUTH-SOUTHEASTERLY BETWEEN 5-10 KTS TONIGHT. AT TIMES ALONG AND AHEAD OF THE FRONTAL PASSAGE...KGFL...KPOU...AND KPSF MAY EXPERIENCE SOME LLWS ESPECIALLY TOWARD THE END OF THE TAF PERIOD. OUTLOOK... SAT NT: HIGH OPERATIONAL IMPACT.BREEZY DEFINITE SHRA...RA...FG. SUN: MODERATE OPERATIONAL IMPACT. WINDY WITH GUSTS TO 34.0 SLIGHT CHANCE OF SHRA. SUN NT-MON: NO OPERATIONAL IMPACT. NO SIG WX. MON NT-WED: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...SHSN. && .HYDROLOGY... A FLOOD WATCH REMAINS IN EFFECT FOR SATURDAY AFTERNOON THROUGH SUNDAY...WITH THE PRIMARY THREAT ICE JAM FLOODING. A POWERFUL STORM SYSTEM WILL MOVE ACROSS THE REGION SATURDAY WITH VERY MILD AIR BEING USHERED IN AS THE SYSTEM APPROACHES WITH TEMPERATURES RISING INTO THE UPPER 40S TO LOWER 50S. THIS WILL LEAD TO SOME SNOW MELT. SOME MIXED WINTRY PRECIPITATION IS EXPECTED LATE TONIGHT INTO EARLY SATURDAY MORNING...THEN RAIN IS EXPECTED INTO SATURDAY NIGHT. THE RAIN MAY BE HEAVY AT TIMES DURING THE AFTERNOON AND EVENING HOURS. RAINFALL AMOUNTS OF ONE HALF OF AN INCH TO AN INCH ARE EXPECTED FROM THE CAPITAL DISTRICT NORTH AND WEST WITH 1 TO 2 INCHES TO THE SOUTH AND EAST. THE RAIN WILL FALL ON FROZEN GROUND WHICH WILL QUICKLY BECOME RUNOFF AND MAY CAUSE SOME STREET AND OR POOR DRAINAGE FLOODING OF LOW LYING AREAS. THE WARM TEMPERATURES...COMBINED WITH THE RAINFALL MAY CAUSE ICE MOVEMENT AND BREAK UP FOR ICE JAM FLOODING ON SOME RIVERS AND STREAMS. THE THREAT FOR ICE JAM FLOODING WILL BE GREATEST LATE SATURDAY AFTERNOON INTO SUNDAY. IT APPEARS THAT THE GREATEST POTENTIAL FOR FLOODING AT THIS TIME WILL INCLUDE...BUT NOT BE LIMITED TO...THE HOOSIC RIVER AT WILLIAMSTOWN AND EAGLE BRIDGE...AND THE WALLOOMSAC RIVER AT BENNINGTON. DESPITE THE PASSAGE OF THE SYSTEM...ABOVE NORMAL TEMPERATURES ARE EXPECTED TO PERSIST THROUGH EARLY NEXT WEEK. NIGHTTIME TEMPERATURES WILL FALL TO AROUND FREEZING OR BELOW. OUR NEXT BEST CHANCES FOR WIDESPREAD PRECIPITATION WILL TUESDAY. 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...FLOOD WATCH FROM SATURDAY AFTERNOON THROUGH SUNDAY AFTERNOON FOR CTZ001-013. FREEZING RAIN ADVISORY FROM 10 PM THIS EVENING TO 4 AM EST SATURDAY FOR CTZ001-013. NY...FLOOD WATCH FROM SATURDAY AFTERNOON THROUGH SUNDAY AFTERNOON FOR NYZ032-033-038>043-047>054-058>061-063>066-082>084. FREEZING RAIN ADVISORY FROM 10 PM THIS EVENING TO 4 AM EST SATURDAY FOR NYZ063>066. FREEZING RAIN ADVISORY FROM MIDNIGHT TONIGHT TO 6 AM EST SATURDAY FOR NYZ047>054-058>061. FREEZING RAIN ADVISORY FROM MIDNIGHT TONIGHT TO 9 AM EST SATURDAY FOR NYZ032-033-038>043-082>084. MA...FLOOD WATCH FROM SATURDAY AFTERNOON THROUGH SUNDAY AFTERNOON FOR MAZ001-025. FREEZING RAIN ADVISORY FROM MIDNIGHT TONIGHT TO 6 AM EST SATURDAY FOR MAZ001-025. VT...FLOOD WATCH FROM SATURDAY AFTERNOON THROUGH SUNDAY AFTERNOON FOR VTZ013>015. FREEZING RAIN ADVISORY FROM MIDNIGHT TONIGHT TO 9 AM EST SATURDAY FOR VTZ013>015. && $$ SYNOPSIS...IAA/KL NEAR TERM...KL/NAS SHORT TERM...KL LONG TERM...IRL AVIATION...NAS HYDROLOGY...IAA/KL/WASULA
AREA FORECAST DISCUSSION
NWS TAUNTON MA
1255 AM EST THU JAN 9 2014 .SYNOPSIS... ARCTIC AIRMASS MOVING OUT AS WARMER AIR ASSOCIATED WITH A HIGH PRESSURE MOVES UP FROM THE SOUTH. A WARMING TEMPERATURE TREND IS ANTICIPATED LATE THIS WEEK. LOCALLY HEAVY RAINFALL AND STRONG WINDS EXPECTED LATE SATURDAY AND SATURDAY NIGHT. MAINLY DRY AND CONTINUED MILD WEATHER EXPECTED EARLY NEXT WEEK. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... 1 AM UPDATE... BKN-OVC MID LVL CLOUDS HAVE DEVELOPED IN ADVANCE OF A SHORTWAVE NOW MOVING INTO THE HUDSON VALLEY THIS MORNING. THE WEAK ECHOS ON UPSTREAM RADARS HAVE BEEN DISSIPATING AS THEY APPROACH THE BOX CWA BORDER BUT STILL FEEL THERE MAY BE A FEW VERY LIGHT FLURRIES POSSIBLE. IN EXTREME W MA/CT THROUGH THE EARLY MORNING HOURS AS THE WAVE APPROACHES. HOWEVER...AM NOTING DECENT SUBSIDENCE DIRECTLY BEHIND THIS FEATURE SO RAPID CLEARING IS EXPECTED THROUGH THE DAYLIGHT HOURS. HAVE ADJUSTED SKIES/POPS/TEMPS/DWPTS WITH THIS UPDATE TO ACCOUNT FOR THIS THINKING. PREVIOUS DISCUSSION... NORTHERN STREAM IMPULSE WILL INVOKE BROAD SCALE ASCENT OF MID- LEVEL MOISTURE /CONTINENTAL IN NATURE/ RESULTING IN SCATTERED TO BROKEN CLOUD DECKS OVERNIGHT /IN ADDITION TO OCEAN-EFFECT CLOUDS ACROSS THE WATERS/. HRRR IS HINTING AT POSSIBLE FLURRIES BUT IT APPEARS THE BETTER ASCENT AND MOISTURE CONVERGENCE WILL REMAIN SOUTH WITH MUCH OF THE REGION UNDER THE INFLUENCE OF STRONG DEEP- LAYER SUBSIDENCE. WILL KEEP WITH A DRY FORECAST...BUT HAVE TO MONITOR CONDITIONS OVERNIGHT FOR THE POSSIBILITY OF FLURRIES...ESPECIALLY ACROSS NORTHERN CONNECTICUT. IN ITS WAKE...HIGH PRES WILL BUILD N FROM THE SE CONUS. CONSIDERING W WINDS /BREEZY ALONG THE SHORES AND ADJACENT WATERS/ AND EXPECTED PARTY TO MOSTLY CLOUDY CONDITIONS...ANTICIPATING A SLIGHTLY WARMER CONDITIONS COMPARED TO LAST NIGHT WITH LOWS AROUND THE UPPER SINGLE DIGITS TO LOW TEENS. && .SHORT TERM /6 AM THIS MORNING THROUGH 6 PM FRIDAY/... THURSDAY... HIGH PRES BUILDING ACROSS THE NE CONUS. WINDS BECOMING LIGHT AND VARIABLE /ALBEIT STILL A LITTLE BRISK OVER THE WATERS AND ADJACENT SHORES/. ABUNDANT SUNSHINE AND CLEAR CONDITIONS WILL RESULT IN HIGHS AROUND THE MID- TO UPPER-20S. THURSDAY NIGHT... HIGH PRES SLIDES E ALLOWING WINDS TO TURN S/SWLY. A WEAK DISTURBANCE APPROACHES OUT OF THE OHIO RIVER VALLEY ALONG AND AHEAD OF WHICH ISENTROPIC ASCENT OF A WARMER-MOIST AIRMASS WILL LEAD TO INCREASING CLOUDS ACROSS THE REGION. THERE IS A SLIGHT CHANCE FOR LIGHT SNOW TOWARDS FRIDAY MORNING. CONSIDERING THE BLANKET OF CLOUDS AND S WINDS...LOWS WILL RANGE AROUND THE LOW- TO MID-TEENS /WARMER ALONG THE SHORES/. && .LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/... HIGHLIGHTS... * GRADUALLY WARMING TOWARDS THIS WEEKEND * LOCALLY HEAVY RAIN AND STRONG WINDS LIKELY LATE SATURDAY INTO EARLY SUNDAY * MAINLY DRY AND MILD EARLY NEXT WEEK OVERVIEW... A PATTERN SHIFT IS STILL EXPECTED DURING THE EXTENDED PERIOD AS POLAR VORTEX RETREATS NORTHWARD. THE LACK OF ANY HIGH LATITUDE BLOCKING WILL BRING A PROGRESSIVE PATTERN AND CONSIDERABLY MILDER CONDITIONS TO OUR REGION. A MID-LEVEL RIDGE BUILDS OVER THE WESTERN ATLANTIC THIS WEEKEND...WHICH WILL BRING A PERIOD OF UNSEASONABLY MILD CONDITIONS. 08/12Z MODEL SUITE CONTINUES TO BE MORE ROBUST WITH AN APPROACHING MID-LEVEL TROUGH AND FRONTAL SYSTEM...SUGGESTING THE MILD WEATHER WILL BE ACCOMPANIED BY A PERIOD OF HEAVY RAIN AND STRONG WINDS ESPECIALLY SATURDAY NIGHT. ECMWF IS SLIGHTLY MORE AMPLIFIED THAN GFS AND HOLDS ON TO THE RAIN THROUGH MUCH OF SUNDAY. WE CONTINUE TOP FAVOR THE MORE PROGRESSIVE SOLUTION PROVIDED BY THE MODEL CONSENSUS WITH GRADUALLY IMPROVING CONDITIONS DURING SUNDAY. WEST COAST RIDGE AND MIDWEST TROUGH SETS UP EARLY NEXT WEEK WITH SOUTHWEST TO WEST FLOW ACROSS NEW ENGLAND...WHICH WILL MAINTAIN RELATIVELY MILD CONDITIONS. FRIDAY...STRONG HIGH PRESSURE ACROSS NEW ENGLAND MOVES OFFSHORE. MODELS ARE STILL FAIRLY AGGRESSIVE IN MOISTENING THE ATMOSPHERE AS A FAST MOVING SHORTWAVE MOVES JUST SOUTH OF NEW ENGLAND. SOME LIGHT QPF IS GENERATED FRI MORNING WHICH MAY MEAN SOME LIGHT SNOW OR FLURRIES FOR OUR REGION. WE HAVE JUST SLIGHT CHANCE POPS FOR NOW. FRIDAY NIGHT INTO SUNDAY...MAINLY DRY FRIDAY NIGHT AS AREA OF MOISTURE MOVES OFFSHORE BUT WILL HAVE TO WATCH POTENTIAL FOR A PERIOD OF LIGHT FREEZING RAIN ACROSS THE INTERIOR TOWARD DAYBREAK SATURDAY AND SATURDAY MORNING AS WARM AIR ADVECTION INCREASES AND DEEPENING MOISTURE RETURNS FROM THE WEST. PRECIPITATION WOULD BE LIGHT...BUT ANY FREEZING RAIN WOULD RESULT IN HAZARDOUS TRAVEL. RAINFALL CHANCES INCREASE LATE SATURDAY AND ESPECIALLY SATURDAY NIGHT AS A COLD FRONT APPROACHES FROM THE WEST. ENSEMBLES AND OPERATIONAL MODELS CONTINUE TO ADVERTISE AND ANOMALOUSLY STRONG SOUTHERLY JET...WHICH WILL BRING A DEEP MOISTURE PLUME OVER OUR REGION SATURDAY NIGHT INTO SUNDAY. HAVE GONE HIGHER THAN MOS GUIDANCE FOR TEMPERATURES SATURDAY AND SATURDAY NIGHT. SHOULD TEMPERATURES BE WARMER THAN CURRENT FORECAST...THE THREAT FOR STRONG WINDS WOULD BE ENHANCED. SHOWERS WILL LINGER INTO SUNDAY MORNING AS A COLD FRONT MOVES THROUGH WITH IMPROVING CONDITIONS POSSIBLE SUNDAY AFTERNOON...BUT TIMING OF FRONTAL PASSAGE AND IMPROVEMENT IS UNCERTAIN. MONDAY... LOOKS MOSTLY DRY AND A BIT COOLER...BUT TEMPERATURES REMAINING ABOVE NORMAL. TUESDAY AND WEDNESDAY...ANOTHER COLD FRONT CROSSING THE REGION SOMETIME IN THIS TIME FRAME COULD BRING MORE SHOWERS TO SOUTHERN NEW ENGLAND. TEMPERATURES WOULD FAVOR RAIN FOR MOST LOCATIONS... WITH A RAIN/SNOW MIX POSSIBLE ACROSS THE INTERIOR. && .AVIATION /05Z THURSDAY THROUGH MONDAY/... FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT TERM /THROUGH FRIDAY/... HIGH CONFIDENCE THROUGH TONIGHT...LOWER CONFIDENCE REGARDING LIGHT SNOW FRIDAY. THROUGH TONIGHT... VFR. GRADUAL CLEARING THROUGH THE DAY TODAY...WITH BUILDING CLOUDS OVERNIGHT TONIGHT. WINDS GENERALLY LIGHT OUT OF THE W-NW. FRIDAY... LIGHT SNOW SHOWERS POSSIBLE DURING THE MORNING HOURS FRIDAY MOVING FROM W TO E INTO MID AFTERNOON. LIGHT ACCUMS POSSIBLE ON SOME RUNWAYS. VFR EXPECTED OUTSIDE OF THESE -SHSN WITH MAINLY MVFR CIGS AND POSSIBLE BRIEF IFR VSBYS DURING THEM. KBOS TAF...HIGH CONFIDENCE IN TAF. KBDL TAF...HIGH CONFIDENCE IN TAF. OUTLOOK...FRIDAY THROUGH MONDAY... FRIDAY...MODERATE CONFIDENCE. A PERIOD OF MVFR CONDITIONS POSSIBLE LATE THU NIGHT INTO FRI MORNING IN SNOW. SATURDAY INTO SATURDAY NIGHT...MODERATE CONFIDENCE. AREAS OF MVFR IN THE MORNING WITH SCATTERED INTERIOR FZRA POSSIBLE. LOWERING TO IFR LATE SATURDAY AND ESPECIALLY SATURDAY NIGHT AS WIDESPREAD RAIN...WITH LOCALLY HEAVY RAINFALL...MOVES INTO THE REGION. STRONG SOUTHERLY WINDS POSSIBLE SATURDAY NIGHT. SUNDAY...LOW CONFIDENCE ON TIMING. MVFR/IFR IN SHOWERS DURING THE MORNING...IMPROVING TO VFR IN THE AFTERNOON. MONDAY...MODERATE CONFIDENCE VFR. && .MARINE... FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. NEAR TERM /THROUGH THURSDAY NIGHT/...HIGH CONFIDENCE. SMALL CRAFTS FOR THE OUTER WATERS...MAINLY FOR SEAS BUT ALSO THE POSSIBILITY OF WESTERLY WIND GUSTS UP TO 25 KTS OVERNIGHT. OCEAN- EFFECT CLOUDS GRADUALLY DISSIPATING. HIGH PRES BUILDS OVER THE WATERS THURSDAY INTO THURSDAY NIGHT ALLOWING WINDS AND SEAS TO CALM. BREEZY WEST WINDS AROUND 10 TO 15 KTS DURING THE DAY MAINLY OVER THE EASTERN WATERS WITH LIGHTER FLOW TO THE SOUTH...VEERING MORE SOUTHERLY OVERNIGHT INTO FRIDAY MORNING. OUTLOOK...FRIDAY THROUGH MONDAY...HIGH CONFIDENCE. SOUTHERLY WINDS INCREASING SATURDAY AFTERNOON WITH GALE FORCE GUSTS POSSIBLE SATURDAY NIGHT AND RAPIDLY BUILDING SEAS TO 10-15 FT OVER OPEN WATERS. WINDS SHIFTING TO WEST DURING SUNDAY WITH SMALL CRAFT ADVISORY GUSTS LIKELY. VSBYS REDUCED IN SHOWERS AND FOG LATE SATURDAY INTO SUNDAY. SMALL CRAFT ADVISORY CONDITIONS LIKELY TO CONTINUE INTO MONDAY...ESPECIALLY ACROSS THE OUTER COASTAL WATERS DUE TO LINGERING ROUGH SEAS. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...NONE. MA...NONE. NH...NONE. RI...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR ANZ250- 254>256. && $$ SYNOPSIS...BELK/SIPPRELL NEAR TERM...DOODY/SIPPRELL SHORT TERM...SIPPRELL LONG TERM...BELK AVIATION...BELK/DOODY MARINE...BELK/SIPPRELL
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1207 AM EST THU JAN 9 2014 .SYNOPSIS... HIGH PRESSURE WILL CONTINUE TO BUILD IN FROM THE WEST THROUGH THURSDAY. AS HIGH PRESSURE MOVES SLOWLY OFFSHORE THEREAFTER...LOW PRESSURE OVER THE SOUTH CENTRAL U.S. WILL INTENSIFY AS IT MOVES NORTHEAST OF THE GREAT LAKES SATURDAY NIGHT. HIGH PRESSURE WILL FOLLOW SUNDAY. ANOTHER LOW IS FORECAST TO MOVE NORTHEAST TOWARD THE AREA TUESDAY. && .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/... BASED ON LATEST RADAR TRENDS...HRRR AND RUC13 HAVE ADDED IN A SLIGHT CHANCE OF FLURRIES OVER W ORANGE COUNTY EARLY THIS MORNING WITH THE ARRIVAL OF A 500-700 HPA TROUGH. TEMPERATURES THEREFORE ARE REMAINING NEARLY STEADY AT THE MOMENT TONIGHT BUT EXPECTING A FEW MORE DEGREES IN TEMPERATURE DROP WHEN THE CLOUDS DECREASE LATE. THEREFORE LOWS REMAIN NEARLY THE SAME AS FORECAST BEFORE...MOSTLY IN THE TEENS MOST LOCATIONS AND LOWER 20S FOR NYC. SINGLE DIGIT LOWS ARE FORECAST FOR PARTS OF THE INTERIOR NORTH AND WEST OF NYC. && .SHORT TERM /6 AM THURSDAY MORNING THROUGH THURSDAY NIGHT/... HIGH PRESSURE MOVES DIRECTLY OVER THE REGION DURING THE DAY THURSDAY WITH WINDS BECOMING NEARLY CALM. SKIES WILL BECOME MOSTLY SUNNY. USED A BLEND OF MODEL GUIDANCE FOR TEMPERATURES ON THURSDAY WITH HIGHS REACHING THE UPPER 20S AND LOWER 30S. HIGHS IN THE NYC METRO AREA AND ALONG THE COAST COULD CLIMB JUST ABOVE THE FREEZING MARK. THE HIGH MOVES OFFSHORE LATE THURSDAY AFTERNOON AND EVENING ALLOWING ANOTHER WEAK SHORTWAVE TO APPROACH FROM THE WEST. EXPECT CLOUDS TO INCREASE THURSDAY EVENING AND OVERNIGHT. SOME LIGHT SNOW MAY DEVELOP VERY LATE THURSDAY NIGHT...ESPECIALLY WEST OF NEW YORK CITY. ANY SNOW THAT DOES DEVELOP WILL BE VERY LIGHT AND LITTLE TO NO ACCUMULATION IS EXPECTED. ONCE AGAIN A MODEL BLEND WAS USED FOR THURSDAY NIGHT LOW TEMPERATURES. EXPECT LOWS IN THE TEENS AND 20S. && .LONG TERM /FRIDAY THROUGH WEDNESDAY/... SATURDAY THROUGH SUNDAY...PREPARE FOR A POTENTIAL HIGH IMPACT HYDROLOGIC EVENT. AN OUTLOOK WILL BE ISSUED COVERING THE POTENTIAL FOR ICE JAM FLOODING ALONG LOCAL AREA RIVERS CAUSED BY HEAVY RAIN AND TEMPERATURES RISING SHARPLY THROUGH THE 50S STARTING SATURDAY AFTERNOON AND EXTENDING THROUGH SUNDAY. IN ADDITION...A WIND SWEPT HEAVY RAIN MAY CAUSE WIDESPREAD URBAN FLOODING AS A FROZEN SURFACE GROUND LAYER THAWS RESULTING IN SIGNIFICANT RUNOFF. THE STRONGEST WINDS ARE FORECAST EAST OF NEW YORK CITY ACROSS LONG ISLAND AND CT WHERE GUSTS OF 40-50 MPH ARE POSSIBLE. ALTHOUGH THERE IS A CHANCE FOR LIGHT SNOW WITH THE APPROACH OF A WEAK UPPER LVL SHORT WAVE AND WEAK LOW LVL WARM AIR ADVECTION ON FRIDAY...THE MAIN FOCUS WILL BE FOR THIS WEEKEND. THE COMBINATION OF A STRONG LARGE HIGH PRESSURE SYSTEM SLOWLY RETREATING OFFSHORE AND AN INTENSIFYING LOW PRES SYSTEM MOVING NORTHEAST ACROSS THE GREAT LAKES WILL RESULT IN RAPID LOW LVL MOISTURE CONVERGENCE AHEAD OF ITS DEVELOPING TRAILING COLD FRONT...AIDED BY THE DEVELOPMENT OF A STRONG LOW LVL SE WIND JET...CAUSING THE DEVELOPMENT OF HEAVY RAIN...STRONG WINDS AND MUCH ABOVE NORMAL TEMPERATURES SATURDAY THROUGH SATURDAY NIGHT. THE POTENTIAL FOR ICE JAM FLOODING ALONG LOCAL AREA RIVERS WILL INCREASE FROM SATURDAY AFTERNOON THROUGH THE DAY SUNDAY. OUR FIRST SPRING FLOOD POTENTIAL OUTLOOK WILL BE ISSUED ON FRIDAY...CONTAINING ADDITIONAL DETAILS. OTHERWISE...STRONG GUSTY WEST WINDS WILL DEVELOP IN ITS WAKE AS HIGH PRESSURE MOVES EAST TOWARD THE AREA ON SUNDAY. FORECAST MODELS ARE SHOWING THE POTENTIAL FOR ANOTHER SIGNIFICANT SYSTEM BY LATE TUESDAY. && .AVIATION /06Z THURSDAY THROUGH MONDAY/... VFR WITH HIGH PRESSURE BUILDING IN. WEST WINDS UNDER 10KT OVERNIGHT. WINDS SHIFT NW ROUGHLY 12-14Z THURSDAY MORNING...STILL UNDER 10KT. BCMG LIGHT AND VRB LATE DAY. OUTLOOK FOR 06Z FRIDAY THROUGH MONDAY... .THURS NIGHT...VFR. .FRI...CHC MVFR IN SCT AM -SHSN AND SCT PM MIX PCPN. .SAT...MVFR LOWERING TO IFR. RAIN. CHC S GUSTS 40KT+ ALONG WITH LIKELY LLWS IN AFTN/EVE HOURS. .SUNDAY...MVFR OR LOWER PSBL IN RAIN EARLY...BCMG VFR. WSW GUSTS 30-40KT. .MONDAY...VFR. WSW GUSTS AROUND 25 KT. && .MARINE... MINOR CHANGES THIS UPDATE TO REFELCT THE LATEST TRENDS IN OBSERVATIONS AND GUIDANCE. FORECAST APPEARS ON TRACK. STRENGTHENING HIGH PRESSURE TO THE WEST IS KEEPING A STRONGER PRESSURE GRADIENT BETWEEN IT AND LOW PRESSURE IN EASTERN CANADA. THEREFORE...GUSTY WINDS REMAIN ACROSS THE WATERS TONIGHT. HOWEVER...GUSTS ARE ONLY EXPECTED TO BE UP TO AROUND 20 KT WITH SEAS REMAINING BELOW 5 FT. WINDS AND SEAS SUBSIDE SIGNIFICANTLY ON THURSDAY WITH HIGH PRESSURE MOVING OVER THE WATERS. THE HIGH MOVES OFFSHORE THURSDAY NIGHT...BUT CONDITIONS WILL REMAIN BELOW SCA LEVELS. PREPARE FOR STRONG WINDS...HIGH SEAS...HEAVY RAIN AND HIGH SURF SATURDAY THROUGH SUNDAY. THE COMBINATION OF A STRONG LARGE HIGH PRESSURE SYSTEM SLOWLY RETREATING OFFSHORE AND AN INTENSIFYING LOW PRES SYSTEM MOVING NORTHEAST ACROSS THE GREAT LAKES WILL RESULT IN SOUTHEAST WINDS INCREASING TO SMALL CRAFT ADVISORY CRITERIA AREA WIDE ON SATURDAY FOLLOWED BY POTENTIAL GALES SATURDAY NIGHT. SEAS BUILDING TO 10 TO 15 FT SATURDAY NIGHT WILL CAUSE HIGH SURF AND BEACH EROSION ACROSS ATLANTIC FACING SHORES LATE SATURDAY THROUGH EARLY SUNDAY. ONCE THE TRAILING COLD FRONT SWEEPS EST OF THE AREA...WINDS WILL SHIFT TO THE WEST AT SMALL CRAFT ADVISORY LEVELS SUNDAY AFTERNOON. WEATHER CONDITIONS WILL GRADUALLY IMPROVE SUNDAY NIGHT INTO MONDAY. && .HYDROLOGY... NO SIGNIFICANT PRECIPITATION IS EXPECTED THROUGH THURSDAY NIGHT. THE NEXT CHANCE FOR A WIDESPREAD HEAVY RAIN OF 1 TO 2 INCHES WILL MAINLY BE FROM SATURDAY AFTERNOON THROUGH SATURDAY NIGHT. BECAUSE CONDITIONS WILL BECOME FAVORABLE FOR ICE JAM FLOODING...A HAZARDOUS WEATHER OUTLOOK WILL BE ISSUED WITH THIS FORECAST UPDATE. && .EQUIPMENT... THE NEW YORK CITY NOAA ALL HAZARDS WEATHER RADIO STATION KWO35 IS OUT OF SERVICE. DUE TO INTERFERENCE ISSUES WITH THE U.S. COAST GUARD EMERGENCY BROADCAST CHANNEL...THE NEW YORK CITY NOAA ALL HAZARDS WEATHER RADIO STATION KWO35 IS OUT OF SERVICE. DURING THE TIME...THE TRANSMITTER MAY BE RETURNED TO SERVICE INTERMITTENTLY FOR USE OF THE NOAA ALL HAZARDS WEATHER RADIO DURING POTENTIALLY DANGEROUS WEATHER SITUATIONS...FOR ROUTINE WEEKLY TEST OF THE WARNING SYSTEM...AND TO DETERMINE IF THE INTERFERENCE ISSUE HAS BEEN RESOLVED. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. NJ...NONE. MARINE...NONE. && $$ SYNOPSIS...BC/GC NEAR TERM...MALOIT/JM/BC SHORT TERM...BC LONG TERM...GC AVIATION...JC MARINE...MALOIT/JM/BC/GC HYDROLOGY...BC/GC EQUIPMENT...
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
952 PM EST FRI JAN 10 2014 .DISCUSSION... CURRENT-TONIGHT...THE WARM FRONTAL BOUNDARY IS WELL NORTH OF EAST CENTRAL FLORIDA THIS EVENING. AN APPROACHING COLD FRONTAL BOUNDARY WILL BE JUST WEST OF THE FLORIDA PANHANDLE BY EARLY SAT MORNING. THE WIND FLOW NEAR THE SURFACE WILL BE LIGHT AND OF A SOUTHERLY COMPONENT. THIS WILL KEEP OVERNIGHT MINS WELL ABOVE NORMAL IN THE MID TO UPPER 60S. THERE HAS BEEN SOME SEA FOG LATE THIS AFTERNOON AND EARLY EVENING LOWERING VISIBILITIES ALONG THE IMMEDIATE VOLUSIA COAST. THUS FAR THIS HAS BEEN HANDLED BY BLOG/NOWCAST/SPECIAL WEATHER STATEMENT AND MARINE WEATHER STATEMENT. WILL CONTINUE TO MONITOR AND HOLD OFF ON ANY DENSE FOG ADVISORY...BUT WITH 925 MB SOUTHERLY WINDS INCREASING TO 20-25 KTS OVERHEAD OVERNIGHT CANNOT IMAGINE THIS WILL BE A CONTINUING PROBLEM. WILL KEEP PATCHY FOG MENTION IN THE ZONES FOR LATE OVERNIGHT AND EARLY SAT MORNING AS WE DO HAVE ABUNDANT LOW LEVEL MOISTURE...BUT WITH THE WINDS JUST OFF THE SURFACE INCREASING BELIEVE THIS WILL BE MORE OF A STRATUS EVENT WITH LOW GRAY CLOUDS LATER TONIGHT...BURNING OFF INTO THE MID MORNING HOURS SAT MORNING. ALL CONVECTION OVER LAND IS DISSIPATING THIS EVENING. WILL DO A ZONES UPDATE SHORTLY TO CLEAN UP FIRST PERIOD WORDING. ...PREVIOUS DISCUSSION FOR SAT-SAT NIGHT BELOW... SAT...FRONTAL BOUNDARY IS PROGGED TO BE ENTERING THE WESTERN PANHANDLE EARLY AND PUSHING THROUGH THE BIG BEND REGION TOWARDS EARLY EVENING. THOUGH LOW LEVEL WINDS WILL BE INCREASING AS THE FRONT APPROACHES...THEY WILL BE VEERING TO THE SOUTHWEST...DECREASING CONVERGENCE. THE GFS ALSO SHOWS THAT THIS SOUTHWEST FLOW WILL TAP DRIER AIR THAT RESIDES OVER THE NORTHWEST CARIBBEAN. THE RESULT FROM THE MODEL IS VERY LOW PRECIP AMOUNTS. BASED ON QUITE HIGH DEW POINTS THOUGH...WILL RETAIN CHANCE POPS WITH VALUES AT 50 PERCENT IN THE NORTH AND 30 IN THE SOUTH. HAVE TRIMMED THUNDER CHANCES BACK TO NORTHERN SECTIONS...JUST AHEAD OF THE FRONT. THE WARM SOUTHWEST FLOW WILL BOOST MAX TEMPS INTO THE 80S. LATEST MOS HAS LOWER 80S NORTH AND MID 80S SOUTH. IF THE MORNING STRATUS BREAKS UP FAST ENOUGH AND PRE FRONTAL PRECIP HOLDS OFF LONG ENOUGH...A FEW SPOTS COULD APPROACH THEIR RECORD HIGHS. SAT NIGHT...A 130KT H30-H20 JET STREAK DIGGING ACRS THE NW CONUS WILL COMBINE WITH A 110KT JET LIFTING OUT OF THE RIO GRANDE VALLEY TO SHUNT THE NEXT SHORT WAVE FRONTAL TROF THROUGH CENTRAL FL. WHILE THE COMBO OF THESE TO UPR LVL FEATURES WILL PROVIDE SUFFICIENT ENERGY TO DRIVE THE FRONTAL BOUNDARY INTO S FL BY DAYBREAK...A STRONG MID LVL ANTICYCLONE OVER THE BAHAMA BANK/NW CARIB WILL DEFLECT THE MAJORITY OF THE SYSTEM ENERGY TO THE N. FURTHERMORE...MODEL SOUNDINGS ARE INDICATING A SIGNIFICANT AMOUNT OF DRY AIR THRU THE H85-H60 LYR WITH DEWPOINT DEPRESSIONS ON THE ORDER OF 10C IMMEDIATELY PRECEDING THE FROPA. THE FCST SOLUTION IS NOT UNREASONABLE...GIVEN THE FACT THAT THE LATEST RUC ANALYSIS SHOWS H85-H70 MEAN RH VALUES AS LOW AS 40PCT. FURTHERMORE...THE LIFTING NATURE OF THE LEADING JET STREAK TYPICALLY IS NOT CONDUCIVE TO SIGNIFICANT OUTBREAKS OF STRONG/SVR WX. FINALLY...DEEP LYR LAPSE RATES ACRS THE GOMEX/SW ATLC ARE RATHER WEAK...GENERALLY AOB 6C/KM. WILL KEEP POPS IN THE 30-40PCT RANGE... SHIFTING FOCUS FOR TSRA ACTIVITY FROM THE NRN CWA BTWN 00Z-06Z...AND THE SRN CWA TO 06Z-12Z TO COINCIDE WITH THE FROPA. TIMING OF THE FROPA WILL RESULT IN A FAIRLY WIDE MIN TEMP SPREAD. AREAS ALONG AND N OF I-4 WILL SEE MINS DROP INTO THE M/U50S DUE TO THEIR LONGER DURATION POST FRONTAL COOL AIR ADVECTION...WHILE AREAS ALONG THE TREASURE COAST WILL HOLD IN THE M/U60S AS THE CRUX OF THE COLD AIR WILL NOT HAVE MADE IT THAT FAR SOUTH BY DAYBREAK. && .AVIATION...CURRENTLY...CONSIDERABLE CLOUDINESS WITH SOME OCCASIONAL PARTLY CLOUDY SKIES IN SPOTS AND MAINLY VFR CONDS EVERYWHERE THIS EVENING. S/SSW WINDS ARE FORECAST TO INCREASE IN THE BOUNDARY LAYER TO 20-25 KTS TONIGHT AND ALREADY SEEING SIGNS OF INCREASING WINDS ON THE KXMR 915 MHZ PROFILER. WHILE THERE COULD BE SOME PATCHY FOG LATE OVERNIGHT INTO EARLY SAT MORNING...STILL FEEL THIS WILL BE MORE OF A STRATUS EVENT WITH LOW CLOUDS (IFR/LIFR) DEVELOPING OVER MUCH OF THE AREA LATER TONIGHT...EVENTUALLY BURNING OFF THROUGH MID TO LATE MORNING. && .MARINE...OVERNIGHT...THE PRESSURE GRADIENT REMAINS FORECAST TO STRENGTHEN ONCE AGAIN TONIGHT BEHIND THE LATEST SURFACE TROUGH NORTH OF THE AREA AND IN ADVANCE OF AN APPROACHING COLD FRONT TO THE WEST. S/SSE WINDS ARE FORECAST TO INCREASE AWAY FROM THE COAST 15-20 KTS AFTER MIDNIGHT AND TOWARD DAYBREAK. NEAR SHORE THE WINDS WILL INCREASE TO 10-15 KTS. WILL CONTINUE CURRENT SCA FOR SEAS OFFSHORE THRU 4AM WITH CAUTIONARY STATEMENTS CONTINUING NEAR SHORE. SEAS 4-6 NEAR SHORE AND 6-8 FT OFFSHORE. SAT-SAT NIGHT...PREVIOUS...SOUTH WINDS STARTING OUT THE DAY WILL SHIFT TO THE SOUTHWEST IN THE AFTERNOON. MARINE MOS INDICATES SPEEDS REACHING 20 KNOTS TOWARDS EVENING AT 41009. SINCE THIS IS A WARM ADVECTION PATTERN (OVER COOL CONTINENTAL SHELF WATERS) AND THERE WILL BE LIMITED FETCH WHEN THE SPEEDS INCREASE LATE...WILL HOLD OFF ON AN ADVISORY WITH THIS PACKAGE...BUT EXPECT ONE MAY BE NEEDED OFFSHORE SAT NIGHT. POOR BOATING CONDITIONS AS A COLD FRONT PUSHES RAPIDLY ACRS THE LCL ATLC. MODERATE TO FRESH SW BREEZE AT SUNSET WILL VEER STEADILY TO THE W BY AROUND MIDNIGHT...THEN TO THE NW BY DAYBREAK. OFFSHORE COMPONENT WILL LIMIT SEA HEIGHTS TO 3-5FT NEARSHORE AND 4-6FT OFFSHORE...UP TO 7FT OVER THE GULF STREAM N OF SEBASTIAN INLET. && .CLIMATE... RECORD HIGHS FOR SATURDAY... DAB 84 SET IN 1991 MCO 86 SET IN 1972 MLB 87 SET IN 1975 VRB 84 SET IN 1972 && .MLB WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. && $$ SEDLOCK/CRISTALDI
AREA FORECAST DISCUSSION...UPDATED
NWS PEACHTREE CITY GA
1238 PM EST THU JAN 9 2014 .PREV DISCUSSION... /ISSUED 1036 AM EST THU JAN 9 2014/ UPDATE... MADE A FEW CHANGES TO THE GRIDS THIS MORNING. HAVE ALREADY SENT AN UPDATE TO REFRESH WORDING AND REMOVE FREEZING DRIZZLE WORDING /WHICH DID NOT END UP MATERIALIZING BUT WITH THE VERY DRY DEWPOINTS IT COULD HAVE BEEN MORE OF A CONCERN IF THE MOISTURE HAD BEEN MORE SIGNIFICANT/. REDUCED POPS FOR THIS MORNING AND MADE SOME ADJUSTMENTS TO OVERNIGHT TO INCREASE THEM A LITTLE AS HRRR IS INDICATING MORE WIDESPREAD PRECIP PUSHING IN. MADE SOME MINOR ADJUSTMENTS TO TEMPS AND DEWPOINTS AS WELL TO ACCOUNT FOR TRENDS...AND LOWERED WIND SPEEDS A TAD AS WELL. UPDATED PRODUCTS WILL BE OUT SHORTLY. TDP PREV DISCUSSION... /ISSUED 632 AM EST THU JAN 9 2014/ PREV DISCUSSION... /ISSUED 412 AM EST THU JAN 9 2014/ SHORT TERM /TODAY THROUGH TONIGHT/... HIGH PRESSURE HAS SHIFTED TO THE EAST THIS MORNING ALONG THE ATLANTIC COAST. IN ADDITION...INSENTROPIC UPGLIDE HAS HELPED INCREASE THE CLOUD COVER ACROSS MUCH OF GA. REGIONAL RADAR HAS BEEN SHOWING SOME LIGHT RETURNS ACROSS THE SE PORTION OF THE FORECAST AREA. THE THICKENED CLOUD COVER HAS HELPED HOLD TEMPS ABOVE FREEZING IN THE SE. REGIONAL RADAR SHOWS SOME LIGHT RETURNS MOVING NORTH FROM THE PANHANDLE. THERE IS AN OB IN COFFEE COUNTY...JUST SOUTH OF THE CWFA...REPORTING DRIZZLE WITH THE RADAR RETURNS. TEMPS IN THE FAR SOUTHEAST ZONES ARE STILL IN THE LOWER 40S BUT DEWPOINTS ARE IN THE UPPER TEENS. DON`T THINK THE EXTREME FAR SOUTHEAST COUNTIES WILL WET BULB DOWN TO FREEZING. HOWEVER..IT STILL REMAINS POSSIBLE THAT PATCHY FREEZING DRIZZLE IS POSSIBLE WHERE TEMPS ARE STILL IN THE LOWER TO MIDDLE 30S AND DEWPOINTS ARE IN THE TEENS TO LOWER 20S. IF FREEZING DRIZZLE DOES DEVELOP...IS IT EXPECTED TO REMAIN SOUTH OF THE METRO AREA THIS MORNING. FOR NOW...WILL CONTINUE WITH THE SPS AS ODDS REMAIN VERY LOW FOR ANY ICE ACCUMULATION AND COVERAGE OF ANY FREEZING DRIZZLE WILL REMAIN LOW. HOWEVER...IF A FEW MORE OBS START REPORTING DRIZZLE IN THE SE...WILL CONSIDER AN ADVISORY. TEMPS ARE EXPECTED TO START RISING TOWARDS DAWN IN THE SE...LIMITING ANY FURTHER POTENTIAL FOR FREEZING DRIZZLE DURING THE MID MORNING HOURS. HOWEVER...ISENTROPIC UPGLIDE WILL CONTINUE THE POTENTIAL FOR LIGHT RAIN MAINLY ACROSS EASTERN SECTIONS OF THE CWFA TODAY AND TONIGHT. HAVE RAISED POPS INTO THE OVERNIGHT HOURS...BUT TEMPS ARE EXPECTED TO REMAIN ABOVE FREEZING...EVEN IN A WEDGE SITUATION. NLISTEMAA LONG TERM /FRIDAY THROUGH WEDNESDAY/... MOISTURE RETURN IN RESPONSE TO A POTENT UPPER LEVEL VORT MAX IS EXPECTED TO BRING SHOWERS TO THE AREA ON FRIDAY. IN HOUSE 4KM WRF SUGGESTS WIDESPREAD SHOWERS ON FRIDAY. MOISTURE RETURN WILL BE FIGHTING THE WEDGE FOR POSITIONING FRIDAY INTO SATURDAY. THE GFS NAM WRF AND ECMWF ALL PRODUCE PRECIPITATION ON FRIDAY FOR OUR AREA. THE SYSTEM ON SATURDAY STILL HAS UNCERTAINTY IN REGARDS TO THE TIMING OF THE FRONT AND THE OVERALL STRUCTURE OF AND POSITIONING OF THE VORT MAX. WPC NOTES THAT THE 00Z GFS AND ECMWF HAVE SPED UP THE TIMING OF THE FRONT AND SYSTEM. ACCORDING TO THESE MODELS...MOST OF THE PRECIP SHOULD FALL FROM 06Z SAT TO 00Z SUN. DECIDED TO GO WITH THE 00Z ECMWF FOR TIMING OF THE SYSTEM. SINCE THE SYSTEM APPEARS TO BE SPEEDING UP OVERALL RAINFALL TOTALS HAVE DECREASED WITH THE SYSTEM. NOW UP TO TWO INCHES OF RAIN SEEMS POSSIBLE. AFTER THIS SYSTEM MOVES THROUGH THE LONG RANGE MODELS DIFFER GREATLY WITH THE NEXT SYSTEM EARLY NEXT WEEK. DECIDED TO INCLUDE A SLIGHT CHANCE POPS ON TUESDAY IN A NOD TO ECMWF. NOW FOR THE MORE PRESSING ISSUE OF THE EXTENDED...THE THREAT OF SEVERE WEATHER ON SATURDAY. SPC DAY 3 OUTLOOK PAINTS A SLIGHT RISK IN EXTREME EAST CENTRAL PORTIONS OF THE CWA. THEY NOTE THAT UNCERTAINTIES WITH MOISTURE RETURN AND THEREFORE INSTABILITY...ONGOING PRECIP AND FROPA TIMING STILL MAKE THE FORECAST UNCERTAIN. MODELS FORECAST 35-50 KT 0-1 KM BULK SHEAR ACROSS THE AREA ON SATURDAY. A QUICK VIEW OF THE MODEL SOUNDINGS DEPICT A 50 TO 60 KT H85 JET ACROSS THE AREA. WHILE SHEAR WILL DEFINITELY BE IN PLACE THE REMAINING QUESTION IS INSTABILITY AS USUAL FOR THIS TIME OF YEAR. MAIN THREATS FROM ANY SEVERE THUNDERSTORM WOULD BE WIND AND POSSIBLY AN ISOLATED TORNADO. THE ECMWF IS SUGGESTIVE OF AN OVERNIGHT HSLC SEVERE WEATHER POSSIBILITY AND THEN THE THREAT MOVING ACROSS THE AREA THROUGH 00Z. AT THIS TIME SEVERE WEATHER STILL LOOKS POSSIBLE...HOWEVER WITH FORECAST UNCERTAINTIES THE THREAT FOR SEVERE WEATHER COULD CHANGE WITH FUTURE FORECASTS. ARG && .AVIATION... 18Z UPDATE... MAINLY MVFR WITH PATCHY VFR THIS AFTERNOON...SHOULD DROP TO MVFR EVERYWHERE BY 00Z TONIGHT AS SCATTERED -RA MOVES IN /HANDLED THIS WITH VCSH/. CIGS DROP THEREAFTER TO IFR AND THEN LIFR BY 10Z AND REMAIN DOWN THROUGH THE REMAINDER OF THE PERIOD. SOME HINTS AT VLIFR CIGS LATE FRIDAY BUT KEPT THEM LIFR FOR NOW. HAVE INTRODUCED MVFR VSBY BUT MAY BE QUITE A BIT LOWER THAN THAT IF CIGS BOTTOM OUT. OFF-AND-ON -RA THROUGH THE DAY FRIDAY BUT AGAIN HANDLED THIS MAINLY WITH VCSH. EAST WINDS 5-10KT THROUGH THE PERIOD /HIGHER AT ATL/. //ATL CONFIDENCE...18Z UPDATE... MEDIUM ON -RA COVERAGE. MEDIUM ON TIMING OF CIG CATEGORY CHANGES. MEDIUM ON VSBYS. HIGH ON WINDS. TDP && .PRELIMINARY POINT TEMPS/POPS... ATHENS 47 36 49 45 / 30 60 50 90 ATLANTA 46 37 49 46 / 30 50 40 100 BLAIRSVILLE 47 35 50 46 / 20 40 50 100 CARTERSVILLE 48 37 49 46 / 30 30 40 100 COLUMBUS 47 40 58 53 / 30 40 30 100 GAINESVILLE 45 36 47 44 / 30 60 50 100 MACON 48 41 59 52 / 30 60 50 70 ROME 49 36 51 47 / 20 20 40 100 PEACHTREE CITY 46 37 50 47 / 30 50 40 100 VIDALIA 53 47 62 56 / 30 50 50 30 && .FFC WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION...UPDATED
NWS PEACHTREE CITY GA
1036 AM EST THU JAN 9 2014 .UPDATE... MADE A FEW CHANGES TO THE GRIDS THIS MORNING. HAVE ALREADY SENT AN UPDATE TO REFRESH WORDING AND REMOVE FREEZING DRIZZLE WORDING /WHICH DID NOT END UP MATERIALIZING BUT WITH THE VERY DRY DEWPOINTS IT COULD HAVE BEEN MORE OF A CONCERN IF THE MOISTURE HAD BEEN MORE SIGNIFICANT/. REDUCED POPS FOR THIS MORNING AND MADE SOME ADJUSTMENTS TO OVERNIGHT TO INCREASE THEM A LITTLE AS HRRR IS INDICATING MORE WIDESPREAD PRECIP PUSHING IN. MADE SOME MINOR ADJUSTMENTS TO TEMPS AND DEWPOINTS AS WELL TO ACCOUNT FOR TRENDS...AND LOWERED WIND SPEEDS A TAD AS WELL. UPDATED PRODUCTS WILL BE OUT SHORTLY. TDP && .PREV DISCUSSION... /ISSUED 632 AM EST THU JAN 9 2014/ PREV DISCUSSION... /ISSUED 412 AM EST THU JAN 9 2014/ SHORT TERM /TODAY THROUGH TONIGHT/... HIGH PRESSURE HAS SHIFTED TO THE EAST THIS MORNING ALONG THE ATLANTIC COAST. IN ADDITION...INSENTROPIC UPGLIDE HAS HELPED INCREASE THE CLOUD COVER ACROSS MUCH OF GA. REGIONAL RADAR HAS BEEN SHOWING SOME LIGHT RETURNS ACROSS THE SE PORTION OF THE FORECAST AREA. THE THICKENED CLOUD COVER HAS HELPED HOLD TEMPS ABOVE FREEZING IN THE SE. REGIONAL RADAR SHOWS SOME LIGHT RETURNS MOVING NORTH FROM THE PANHANDLE. THERE IS AN OB IN COFFEE COUNTY...JUST SOUTH OF THE CWFA...REPORTING DRIZZLE WITH THE RADAR RETURNS. TEMPS IN THE FAR SOUTHEAST ZONES ARE STILL IN THE LOWER 40S BUT DEWPOINTS ARE IN THE UPPER TEENS. DON`T THINK THE EXTREME FAR SOUTHEAST COUNTIES WILL WET BULB DOWN TO FREEZING. HOWEVER..IT STILL REMAINS POSSIBLE THAT PATCHY FREEZING DRIZZLE IS POSSIBLE WHERE TEMPS ARE STILL IN THE LOWER TO MIDDLE 30S AND DEWPOINTS ARE IN THE TEENS TO LOWER 20S. IF FREEZING DRIZZLE DOES DEVELOP...IS IT EXPECTED TO REMAIN SOUTH OF THE METRO AREA THIS MORNING. FOR NOW...WILL CONTINUE WITH THE SPS AS ODDS REMAIN VERY LOW FOR ANY ICE ACCUMULATION AND COVERAGE OF ANY FREEZING DRIZZLE WILL REMAIN LOW. HOWEVER...IF A FEW MORE OBS START REPORTING DRIZZLE IN THE SE...WILL CONSIDER AN ADVISORY. TEMPS ARE EXPECTED TO START RISING TOWARDS DAWN IN THE SE...LIMITING ANY FURTHER POTENTIAL FOR FREEZING DRIZZLE DURING THE MID MORNING HOURS. HOWEVER...ISENTROPIC UPGLIDE WILL CONTINUE THE POTENTIAL FOR LIGHT RAIN MAINLY ACROSS EASTERN SECTIONS OF THE CWFA TODAY AND TONIGHT. HAVE RAISED POPS INTO THE OVERNIGHT HOURS...BUT TEMPS ARE EXPECTED TO REMAIN ABOVE FREEZING...EVEN IN A WEDGE SITUATION. NLISTEMAA LONG TERM /FRIDAY THROUGH WEDNESDAY/... MOISTURE RETURN IN RESPONSE TO A POTENT UPPER LEVEL VORT MAX IS EXPECTED TO BRING SHOWERS TO THE AREA ON FRIDAY. IN HOUSE 4KM WRF SUGGESTS WIDESPREAD SHOWERS ON FRIDAY. MOISTURE RETURN WILL BE FIGHTING THE WEDGE FOR POSITIONING FRIDAY INTO SATURDAY. THE GFS NAM WRF AND ECMWF ALL PRODUCE PRECIPITATION ON FRIDAY FOR OUR AREA. THE SYSTEM ON SATURDAY STILL HAS UNCERTAINTY IN REGARDS TO THE TIMING OF THE FRONT AND THE OVERALL STRUCTURE OF AND POSITIONING OF THE VORT MAX. WPC NOTES THAT THE 00Z GFS AND ECMWF HAVE SPED UP THE TIMING OF THE FRONT AND SYSTEM. ACCORDING TO THESE MODELS...MOST OF THE PRECIP SHOULD FALL FROM 06Z SAT TO 00Z SUN. DECIDED TO GO WITH THE 00Z ECMWF FOR TIMING OF THE SYSTEM. SINCE THE SYSTEM APPEARS TO BE SPEEDING UP OVERALL RAINFALL TOTALS HAVE DECREASED WITH THE SYSTEM. NOW UP TO TWO INCHES OF RAIN SEEMS POSSIBLE. AFTER THIS SYSTEM MOVES THROUGH THE LONG RANGE MODELS DIFFER GREATLY WITH THE NEXT SYSTEM EARLY NEXT WEEK. DECIDED TO INCLUDE A SLIGHT CHANCE POPS ON TUESDAY IN A NOD TO ECMWF. NOW FOR THE MORE PRESSING ISSUE OF THE EXTENDED...THE THREAT OF SEVERE WEATHER ON SATURDAY. SPC DAY 3 OUTLOOK PAINTS A SLIGHT RISK IN EXTREME EAST CENTRAL PORTIONS OF THE CWA. THEY NOTE THAT UNCERTAINTIES WITH MOISTURE RETURN AND THEREFORE INSTABILITY...ONGOING PRECIP AND FROPA TIMING STILL MAKE THE FORECAST UNCERTAIN. MODELS FORECAST 35-50 KT 0-1 KM BULK SHEAR ACROSS THE AREA ON SATURDAY. A QUICK VIEW OF THE MODEL SOUNDINGS DEPICT A 50 TO 60 KT H85 JET ACROSS THE AREA. WHILE SHEAR WILL DEFINITELY BE IN PLACE THE REMAINING QUESTION IS INSTABILITY AS USUAL FOR THIS TIME OF YEAR. MAIN THREATS FROM ANY SEVERE THUNDERSTORM WOULD BE WIND AND POSSIBLY AN ISOLATED TORNADO. THE ECMWF IS SUGGESTIVE OF AN OVERNIGHT HSLC SEVERE WEATHER POSSIBILITY AND THEN THE THREAT MOVING ACROSS THE AREA THROUGH 00Z. AT THIS TIME SEVERE WEATHER STILL LOOKS POSSIBLE...HOWEVER WITH FORECAST UNCERTAINTIES THE THREAT FOR SEVERE WEATHER COULD CHANGE WITH FUTURE FORECASTS. ARG AVIATION... 12Z UPDATE... ATL IS ON THE CUSP OF THE LOWER CLOUDS THIS MORNING. DO THINK ATL WILL GO BKN AROUND 14Z THIS MORNING. CIGS SHOULD REMAIN VFR THROUGH THE REMAINDER OF THE TAF PERIOD. SOME PATCHY LIGHT RAIN IS POSSIBLE OVERNIGHT AND INTO FRIDAY. EAST WINDS AOB 10 KT THROUGH THE PERIOD. //ATL CONFIDENCE...12Z UPDATE... MEDIUM-LOW CONFIDENCE ON WHEN CIGS THROUGH THE EARLY AFTERNOON. HIGH CONFIDENCE REMAINING ELEMENTS. && .PRELIMINARY POINT TEMPS/POPS... ATHENS 47 36 49 45 / 30 50 40 80 ATLANTA 46 37 49 46 / 30 50 30 80 BLAIRSVILLE 47 35 50 46 / 20 50 40 80 CARTERSVILLE 48 37 49 46 / 30 40 30 80 COLUMBUS 47 40 58 53 / 30 50 30 80 GAINESVILLE 45 36 47 44 / 30 50 50 80 MACON 48 41 59 52 / 30 50 30 70 ROME 49 36 51 47 / 20 30 30 80 PEACHTREE CITY 46 37 50 47 / 30 50 30 80 VIDALIA 53 47 62 56 / 30 50 30 50 && .FFC WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
922 PM CST FRI JAN 10 2014 .DISCUSSION... 857 PM CST REGIONAL SATELLITE IMAGERY SHOWS A PRONOUNCED MID LEVEL DRY SLOT PUNCHING IN ACROSS EASTERN IOWA AND FAR NORTHWESTERN ILLINOIS THIS EVENING. THIS FEATURE SHOULD CONTINUE EASTWARD ACROSS NORTHERN ILLINOIS OVERNIGHT...AND THIS WILL MARK AN END TO THE MUCH OF THE RAIN AND A TRANSITION TO DRIZZLE AND FOG ACROSS MUCH OF THE AREA AFTER MIDNIGHT. I WILL CONTINUE THE CURRENT FREEZING RAIN HEADLINE AS IS FOR NOW...DUE TO ALL THE REPORTS OF ICING AND BAD TRAVEL CONDITIONS ON AREA ROADS AND SIDE WALKS. WITH TIME...TEMPERATURES AND DEW POINTS IN THE MID TO UPPER 30S SHOULD SLOWLY WARM THE GROUND ENOUGH TO LIMIT ICING OVERNIGHT...BUT BY THIS TIME MOST OF THE PRECIP SHOULD BE DONE ANYWAYS. THE OTHER CONCERN WE ARE WATCHING OVER THE NEXT FEW HOURS IS THAT OF DENSE FOG. SEVERAL SITES ACROSS EASTERN IOWA AND INTO NORTHWESTERN ILLINOIS ARE REPORTING VISIBILITIES DROPPING DOWN AROUND A QUARTER MILE IN FOG. IT APPEARS THE MAIN THREAT FOR DENSE FOG WILL FOLLOW CLOSELY WITH THE TRACK OF THE SURFACE LOW...WHICH IS EXPECTED TO PUSH RIGHT ACROSS NORTHWESTERN ILLINOIS AND SOUTHERN WISCONSIN TONIGHT. SOME OF THIS DENSER FOG COULD GET INTO MY WESTERN AREAS. HOWEVER...I AM A LITTLE RELUCTANT TO ISSUE A DENSE FOG ADVISORY FOR THESE AREAS AS IT APPEARS THE DENSER FOG MAY BE SHORT LIVED...ONLY LASTING A COUPLE HOURS...WITH CONDITIONS IMPROVING RAPIDLY WITH THE PASSAGE OF THE SURFACE LOW AND COLD FRONT. I WILL CONTINUE TO MONITOR THE TRENDS...AND I MAY JUST COVER WITH AN SPS UNLESS IT BECOMES CLEAR THAT THE FOG COULD LAST A BIT LONGER. KJB //PREV DISCUSSION... 624 PM CST WE DECIDED TO ISSUE A FREEZING RAIN ADVISORY THROUGH THIS EVENING. ALTHOUGH AIR TEMPERATURES CONTINUE TO WARM TO NEAR 40...THE COLD GROUND IS ALLOWING AREA ROADS TO BECOME ICY. WE RECEIVED NUMEROUS REPORTS OF ACCIDENTS AND EVEN CLOSED HIGHWAYS ACROSS NORTH CENTRAL ILLINOIS. THE ILLINOIS STATE POLICE IS URGING DRIVERS TO STAY HOME THIS EVENING ACROSS NORTH CENTRAL ILLINOIS. GIVEN HOW BAD CONDITIONS APPEAR TO BE...WE HAVE OPTED TO GO WITH A FREEZING RAIN ADVISORY IN SPITE OF CONTINUED WARMING. WITH TIME THE ROAD TEMPS SHOULD WARM AND END THE THREAT FOR ICING. KJB && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 03Z... * VSBY EXPECTED TO LOWER INTO LATE EVENING...WITH SUB 1SM VSBY POSSIBLE AT TIMES FOR A FEW HOURS. * IFR/LIFR CIGS CONTINUING THROUGH SATURDAY MORNING WITH IMPROVEMENT TO MVFR EXPECTED TOWARD MIDDAY. * SCATTERED SNOW SHOWERS POSSIBLE FOR A SHORT TIME AFTER SUNRISE. * SOUTH WINDS TURNING WESTERLY OVERNIGHT. MDB //DISCUSSION...UPDATED 03Z... SHOWER ACTIVITY CONTINUES TO MOVE ACROSS NORTHEAST ILLINOIS AND NORTHWEST INDIANA THIS EVENING THOUGH COVERAGE WILL BE MUCH LOWER THAN PREVIOUS HOURS. VSBY HAS IMPROVED AT THE TERMINALS BUT LOWER VSBY IS MOVING NORTHEASTWARD TOWARD THE AREA...WITH RFD LIKELY SEEING REDUCTION TO IFR OR LIFR SOON. MAGNITUDE OF REDUCTION AT ORD/MDW/DPA/GYY REMAINS THE BIG CONCERN. IT APPEARS THAT THE LOWEST VSBY WILL REMAIN WEST OF THESE TERMINALS BUT REDUCTIONS DOWN TO AROUND 1SM STILL LOOK LIKELY AT LEAST FOR A FEW HOUR PERIOD GOING INTO THE OVERNIGHT. SOUTH WINDS WILL TURN WESTERLY OVERNIGHT AS DRIER AIR ARRIVES SO VSBY SHOULD IMPROVE LATE...THOUGH CIGS WILL PROBABLY REMAIN IFR/LIFR OVERNIGHT. MDB FROM 00Z... LOW PRESSURE CONTINUES TO MOVE NORTHEAST ACROSS SOUTHERN IOWA WITH A WARM FRONT MOVING NORTHWARD TOWARD THE TERMINALS. RAIN WILL CONTINUE ACROSS THE TERMINALS FOR THE NEXT FEW HOURS WITH VARIATIONS IN VSBY WITH OBS SHOWING VALUES IN THE 2-4SM RANGE WITH SOME SPOTTY 1SM VSBY POSSIBLE AS WELL. IFR/LIFR CIGS CONTINUE WITH OCCASIONAL VARIABILITY BUT EXPECT THAT STEADY IFR/LIFR WILL PREVAIL THROUGH THE NIGHT. THE BULK OF THE RAIN WILL EXIT FROM WEST TO EAST THROUGH MID EVENING AS A COOL FRONTAL BOUNDARY APPROACHES FROM THE WEST. VSBY TRENDS BECOME THE MAIN CONCERN FROM MID EVENING THROUGH MUCH OF TONIGHT AS WARMER AND MORE MOIST AIR LIFTS INTO THE AREA BEHIND THE WARM FRONT AND AHEAD OF THE COLD FRONT. CURRENT OBS SHOW VSBY OF 3/4SM OR LESS ACROSS MUCH OF CENTRAL/EASTERN IOWA AND NORTH CENTRAL MISSOURI. WITH THE LOW LIFTING NORTHEAST THIS LOWEST VSBY MAY BE DRAGGED NORTHEAST TO THE POINT WHERE THE WORST OF IT REMAINS WEST OF THE TERMINALS. WITH WARMER AND MORE MOIST AIR APPROACHING DO EXPECT THAT VSBY WILL FALL THIS EVENING BUT AM NOT SURE THAT IT WILL RESULT IN DENSE FOG. WILL CONTINUE WITH 1SM FOR NOW AND MONITOR OBS OVER THE NEXT FEW HOURS TO DETERMINE OF ANY LOWERING IS NEEDED. OTHERWISE SOME LIGHT RAIN OR DRIZZLE WILL LIKELY CONTINUE INTO THE OVERNIGHT. WINDS WILL TURN SOUTH-SOUTHWEST THIS EVENING. THE COLD FRONT WILL PASS OVERNIGHT TURNING WINDS WESTERLY AND ALLOW SOME LOW LEVEL DRYING TO OCCUR. THIS SHOULD ALLOW VSBY TO MARKEDLY IMPROVE PRIOR TO DAYBREAK BUT CEILINGS WILL LIKELY REMAIN IFR THROUGH AT LEAST SOME OF THE MORNING HOURS. AN IMPROVEMENT TO MVFR IS EXPECTED...WITH SCATTERING POSSIBLE LATER IN THE DAY. WILL NEED TO MONITOR THE POTENTIAL FOR SOME SNOW SHOWERS JUST AFTER DAYBREAK AS AN UPPER LEVEL TROUGH PASSES...BUT THIS LOOK TO OCCUR OVER A SHORT PERIOD. MDB //ORD AND MDW CONFIDENCE...UPDATED 03Z... * MEDIUM CONFIDENCE IN VSBY REDUCTION LATE EVENING/EARLY OVERNIGHT...LOW CONFIDENCE IN MAGNITUDE. * HIGH CONFIDENCE IN IFR/LIFR CIGS THROUGH TONIGHT...MEDIUM CONFIDENCE IN HOW QUICKLY THEY IMPROVE SATURDAY MORNING. * LOW CONFIDENCE IN SNOW SHOWER POTENTIAL SATURDAY MORNING. * HIGH CONFIDENCE IN WIND TRENDS. MDB //OUTLOOK FOR ORD/MDW FOR 12Z SUNDAY-12Z FRIDAY...UPDATED 00Z... SUNDAY...STRONG SOUTH WINDS...LLWS POSSIBLE AFTERNOON/EARLY EVENING. VFR PROBABLE. MONDAY...VFR. TUESDAY...CHANCE OF SNOW/IFR. WEDNESDAY AND THURSDAY...VFR PROBABLE. MDB && .MARINE... 209 PM CST LARGE DOME OF HIGH PRESSURE OVER THE EASTERN SEABOARD HAS DRIFTED EAST...AND STRETCHES FROM CENTRAL QUEBEC SOUTH THROUGH THE CAROLINA COAST. MEANWHILE ACROSS THE CENTRAL PLAINS A SERIES OF LOW PRESSURES EXISTED...WITH ONE ACROSS THE NORTHERN PLAINS AND THE SECOND ACROSS THE CENTRAL PLAINS. THESE TWO AREAS OF LOW PRESSURES WILL CONVERGE UPON LAKE MICHIGAN...CONSOLIDATING INTO A SLIGHTLY STRONGER LOW PRESSURE OVER THE NORTHERN PORTION OF LAKE MICHIGAN EARLY SATURDAY MORNING. WINDS FOR MUCH OF THE LAKE WILL REMAIN SOUTHERLY...WITH THE FAR NORTHERN PORTIONS NEAR THE STRAITS OF MACKINAW BEING SLIGHTLY SOUTHEAST/EAST. THEN WITH THE LOW PASSAGE EXPECTED TO OCCUR SATURDAY MORNING WITH A TRAILING FRONTAL BOUNDARY SLIDING EAST ACROSS THE LAKE...THE GRADIENT IS EXPECTED TO TIGHTEN. FOR THE CENTRAL/SOUTHERN PORTIONS WINDS WILL INCREASE TO NEAR 30 KT BY MIDDAY/EARLY AFTN SAT. THEN AS THE FRONTAL BOUNDARY CONTINUES TO PRESS EAST...WINDS WILL TURN MORE TO THE WEST. FOR THE NORTHERN HALF OF THE LAKE WINDS FOR A PERIOD WILL BECOME NORTHWEST...BEFORE RELAXING TO THE WEST SAT LATE AFTN. HIGH PRESSURE ACROSS THE SOUTHERN PLAINS SAT AFTN WILL CONTINUE TO SLIDE EAST...STRETCHING AN INFLUENCE NORTH TO LAKE MICHIGAN SATURDAY NIGHT/EARLY SUN. THIS COUPLED WITH YET ANOTHER LOW PRESSURE SYSTEM BEGINNING TO PUSH INTO CENTRAL CANADA...WILL ALLOW THE GRADIENT TO TIGHTEN. WINDS SHOULD REMAIN BREEZY SUN AFTN/EVE. THE GRADIENT HAS BECOME SLIGHTLY TIGHTER...ALONG WITH THE LOW PRESSURE BECOME DEEPER TO 28.9 INCHES JUST NORTH OF LAKE SUPERIOR SUN EVE. THIS WILL LIKELY CREATE A PERIOD OF GALES FOR THE LAKE DURING THE SUN AFTN/EVE TIMEFRAME. THE GRADIENT THEN BEGINS TO SLACKEN OFF FOR THE MIDDLE OF NEXT WEEK...WITH JUST A COUPLE WEAK WAVES TRAVERSING THE WESTERN GREAT LAKES REGION. IN THE LONGER RANGE PERIODS FORECAST GUIDANCE IS BEGINNING TO INDICATE A STRENGTHENING LOW PRESSURE OVER THE OHIO VALLEY TUE NIGHT...WHICH COULD RESULT IN A TIGHTENING GRADIENT FOR LAKE MICHIGAN WED AND BREEZY CONDITIONS RETURNING. BEACHLER && .LOT WATCHES/WARNINGS/ADVISORIES... IL...FREEZING RAIN ADVISORY...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008- ILZ010-ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021- ILZ022 UNTIL MIDNIGHT SATURDAY. IN...NONE. LM...NONE. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
  [top] Area Forecast Discussion National Weather Service Lincoln IL 905 PM CST Fri Jan 10 2014 .DISCUSSION... ISSUED 900 PM CST Fri Jan 10 2014 Dense fog potential will increase as the cold front progresses across Illinois. We already issued a dense fog advisory for areas NW of the IL river, but the latest runs of the RAP and HRRR both show dense fog developing after midnight across nearly all of the remainder of the KILX CWA. Forecast soundings and current dewpoint depressions support that scenario, so may need to expand the advisory eastward by late evening. Upstream obs along the southern portion of the cold front are not as supportive of dense fog farther southeast, but we have had more snow melt from a deeper snow pack in our areas. Steady rainfall has generally become confined to areas southeast of I-70. A secondary batch of rain has redeveloped from STL to Jacksonville and is progressing to the ENE into our area. It should mainly affect areas along and southeast of I-55 over the next 4-6 hours. Colder air arriving behind the cold front will have the potential to change any lingering sprinkles or light rain west of I-55 into snow. However, subsidence should prevail by that time and precip should be minimal after the cold air arrives. Low temperatures are expected to dip below freezing NW of the IL river, with around freezing east to the I-55 corridor. That could help create some slippery conditions on untreated and secondary roads. Updates to the forecast grids this evening mainly covered the addition of fog and dense fog, as well as minor low temp adjustments. We also added slight chance of rain or snow lingering in the NE early Sat morning. The remainder of the forecast looks on track. Updated info will be available shortly. Shimon && .AVIATION... ISSUED 558 PM CST Fri Jan 10 2014 The dry slot aloft will shut down the steady rains quickly this evening. PIA and SPI should see rain end between 00z-01z, with the BMI btwn 01z-02z. CMI and DEC may see a break in the rain for a few hours after the initial dry slow passes, but an additional wave of rain is projected to affect areas southeast of DEC to CMI later this evening. They may see some light rain as that feature moves across southeast IL. Dry conditions should prevail the remainder of the night as colder air arrives after midnight. No precip is expected to be falling when temps drop far enough for any rain to change to snow. Forecast soundings show ceiling heights will remain LIFR the rest of the night. Once mixing develops after sunrise on Saturday, LCL heights should climb to around 1500FT for the bulk of the morning. Clearing is projected to begin developing around SPI/PIA toward 18z, and then advance eastward during the afternoon. Winds are expected to be southerly this evening, with a wind shift to W-SW by late evening as the cold front advances to the east. South wind speeds will remain brisk the evening in the 14-16kt range with gusts to 22kt at times. Once the winds veer to the west, gusts may subside initially. However, wind gusts are expected to develop toward sunrise as pressure rises continue behind the departing frontal system. Shimon && .PREV DISCUSSION... ISSUED 253 PM CST Fri Jan 10 2014 Main issues for this forecast package include the rain tonight and then more chances for end of the weekend and beginning of next week. Models look in pretty good agreement through about 66hrs but then differ with intensity of next system and the resulting precip. Extended models do begin to look better once we get to the end of next week. So, confidence in forecast in the near term is good, but wanes with the next system(s) for the end of the weekend and the beginning of next week. So, will take a blend for now. SHORT TERM...Tonight through Monday Rain will continue to move across the area tonight and should begin to wane after midnight, and then be east and northeast of the area by morning. By then, the low pressure area associated with the pcpn will have moved into the Grt Lks region and the 500mb trough will be pushing through the region. So, beyond tonight, dry weather is expected for tomorrow through Sunday. After some ridging, another weak front will move into the area late Sunday night. The return of moisture ahead of this system looks weak and doesn`t seem to arrive until the frontal system is about halfway through the area. So will have chance of pcpn for Monday in the east and southeast only. Will also have a slight chc of pcpn for Sun night, but this will not show up in the worded forecast. Pcpn type should also be just rain as temps should be warm enough through the atmosphere to support all liquid and nothing frozen, and surface temps will be above freezing. Temps will continue to warm as area sits in a somewhat zonal pattern for the weekend. Guidance numbers look ok, but went a little warmer in the southeast for tonight. LONG TERM...Monday night through Friday The beginning of the extended is where the models really look different. The GFS brings another wave down across the area for Monday night through Tue, while the ECMWF has stronger southern stream energy that holds some pcpn back for Monday night and into Tuesday. Because of the differences, not confident enough to put chc pops in the forecast at this time. So will just have slight chc pops for the time period. Both models show a second wave/trough coming into the area from the northwest, so little bit cooler weather will move into the region. This will cause the pcpn type to be more of snow or rain/snow mix in the south part of the cwa. However, since this will be slight chc, the pops will not be seen in the worded forecast. But cloudy skies will be mentioned. Remainder of the extended period, and next week, will be dry. GFS brings additional chances of pcpn through the area, but ECMWF does not. For now, going with a dry forecast seems best. Temps will slightly warmer for Tue, but then become cooler again for Wed and again on Friday. MEX numbers seem to have a good handle on this currently. Auten && .ILX WATCHES/WARNINGS/ADVISORIES... DENSE FOG ADVISORY until 6 AM CST Saturday FOR ILZ027>030-036- 040. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
628 PM CST FRI JAN 10 2014 .DISCUSSION... 624 PM CST WE DECIDED TO ISSUE A FREEZING RAIN ADVISORY THROUGH THIS EVENING. ALTHOUGH AIR TEMPERATURES CONTINUE TO WARM TO NEAR 40...THE COLD GROUND IS ALLOWING AREA ROADS TO BECOME ICY. WE RECEIVED NUMEROUS REPORTS OF ACCIDENTS AND EVEN CLOSED HIGHWAYS ACROSS NORTH CENTRAL ILLINOIS. THE ILLINOIS STATE POLICE IS URGING DRIVERS TO STAY HOME THIS EVENING ACROSS NORTH CENTRAL ILLINOIS. GIVEN HOW BAD CONDITIONS APPEAR TO BE...WE HAVE OPTED TO GO WITH A FREEZING RAIN ADVISORY IN SPITE OF CONTINUED WARMING. WITH TIME THE ROAD TEMPS SHOULD WARM AND END THE THREAT FOR ICING. KJB && .PREV DISCUSSION... 326 PM CST THE RAPIDLY EVOLVING NEXT 18 TO 24 HOURS APPEAR TO BE THE MOST CHALLENGING PORTION OF THE FORECAST FOR THE WEEKEND INTO NEXT WEEK. ISOLATED THUNDERSTORMS HAVE MOVED INTO THE AREA THIS AFTERNOON AND SUBFREEZING TEMPERATURES HAVE FOR THE MOST PART MOVED OUT...AT LEAST FOR THE TIME BEING. THE PRIMARY FORECAST CONCERNS IN THE NEAR TERM INCLUDE DENSE FOG AND THE POSSIBLE NEED FOR AN ADVISORY LATER TONIGHT...THUNDERSTORM TRENDS AND COVERAGE...AND THE FLOOD POTENTIAL GIVEN THE EXPECTED RAINFALL AND WARMING TEMPERATURES. AS MENTIONED IN THE MORNING AFD UPDATE...THE FIRST QUESTION WOULD BE WHETHER DENSE FOG DEVELOPS IN THE SATURATED SURFACE LAYER MOVING IN OVER THE SNOWPACK WITH INCREASING DEWPOINTS. OBSERVATIONS JUST UPSTREAM OF THE AREA ARE SHOWING VSBYS AT WORST AROUND 1 MILE AND GENERALLY QUITE A BIT HIGHER...BUT FARTHER WEST AND SOUTHWEST TOWARD THE APPROACHING LOW CENTER THEY ARE MORE COMMONLY AROUND 1/4 TO 1/2 MILE. STILL AM NOT ANTICIPATING THE NEED FOR FOG HEADLINES IN THE IMMEDIATE TERM. WINDS IN THE TEENS AND MODERATE RAIN ACTUALLY SEEM TO BE HELPING THINGS AS WELL...BUT THE EVENING SHIFT WILL NEED TO REEVALUATE IN CASE CONDITIONS DETERIORATE AND A HEADLINE BECOMES NECESSARY LATE THIS EVENING OR OVERNIGHT. THE AREA OF THUNDERSTORMS SEEN EARLIER TODAY AROUND QUINCY HAS NOW MOVED INTO THE LOCAL AREA AS ANTICIPATED...IN CONJUNCTION WITH THE INCREASING LOW LEVEL MOISTURE FLUX DEPICTED IN THE RAP MODEL EAST OF THE APPROACHING LOW PRESSURE CENTER. AM NOT SEEING ANYTHING TO SUGGEST THIS ACTIVITY WILL BECOME WIDESPREAD THIS EVENING AS THE LOW LIFTS NORTHEAST...BUT WILL MAINTAIN A FIRST PERIOD MENTION OF ISOLATED TO SCATTERED THUNDERSTORMS MAINLY FOR THE SOUTHERN HALF OF THE AREA. AS FOR FLOODING POTENTIAL...HAVE BEEN CONSIDERING A FLOOD ADVISORY FOR URBAN AREAS WHERE RAIN MAY BE PONDING DUE TO DRAINS CLOGGED WITH ICE AND SNOW. AM NOT PLANNING ON ANY AREAL FLOOD WARNING HEADLINES AT THIS TIME GIVEN SO MANY VARIABLES...INCLUDING LOCATION OF HEAVIER RAIN AMOUNTS...DEGREE TO WHICH THE SNOWPACK WOULD SPONGE UP THE RAIN...EVOLUTION OF DEWPOINT TEMPERATURES...AND THE BEHAVIOR OF ICE ON THE RIVERS AND STREAMS. THE BEST POTENTIAL FOR MAINSTEM FLOODING STILL APPEARS TO BE LIMITED TO THE KANKAKEE WHERE A FLOOD WARNING WAS ISSUED EARLIER FOR ANTICIPATED MINOR FLOODING. THE OTHER RIVERS HAVE A LITTLE MORE ROOM TO HANDLE THE RUNOFF. FOR TONIGHT INTO TOMORROW MORNING...MAY TWEAK THE TIMING A BIT BUT AM NOT PLANNING ANY BIG CHANGES TO PRECIPITATION TRENDS. STILL EXPECTING MAINLY RAIN OVERNIGHT...EVOLVING TO DRIZZLE AND MAYBE A PERIOD OF LIGHT SNOW AS COLD AIR MOVES IN TOWARD MORNING. THE REMAINDER OF THE WEEKEND LOOKS DRY AND RELATIVELY MILD WITH SOUTHERLY WINDS AND CLEARING SKIES SUNDAY. NEXT WEEK BRINGS A RETURN TO SOMEWHAT MORE SEASONABLE...THOUGH STILL BELOW NORMAL...TEMPERATURES AND MULTIPLE PERIODS OF LIGHT SNOW POTENTIAL CORRESPONDING TO COLD FRONTAL PASSAGES. THE PRIMARY SURFACE CYCLONE TRACK APPEARS TO STAY NORTH OF THE LOCAL AREA. THE MOST PRONOUNCED COLD AIR INTRUSION LOOKS POISED TO ARRIVE LATE IN THE WEEK...POTENTIALLY KEEPING HIGHS ONLY IN THE TEENS NEXT FRIDAY. LENNING && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 00Z... * VARIABLE VSBY BETWEEN AROUND 2 AND 5SM IN RAIN THROUGH EARLY/MID EVENING. VSBY REDUCTION DOWN TO AROUND 1SM POSSIBLE MID/LATE EVENING AS RAIN DIMINISHES...LOWER VSBY POSSIBLE. * IFR/LIFR CIGS CONTINUING THROUGH SATURDAY MORNING WITH IMPROVEMENT TO MVFR EXPECTED TOWARD MIDDAY. * SCATTERED SNOW SHOWERS POSSIBLE FOR A SHORT TIME AFTER SUNRISE. * SOUTH-SOUTHEAST WINDS TURNING SOUTH-SOUTHWEST MID EVENING...THEN WESTERLY OVERNIGHT. MDB //DISCUSSION...UPDATED 00Z... LOW PRESSURE CONTINUES TO MOVE NORTHEAST ACROSS SOUTHERN IOWA WITH A WARM FRONT MOVING NORTHWARD TOWARD THE TERMINALS. RAIN WILL CONTINUE ACROSS THE TERMINALS FOR THE NEXT FEW HOURS WITH VARIATIONS IN VSBY WITH OBS SHOWING VALUES IN THE 2-4SM RANGE WITH SOME SPOTTY 1SM VSBY POSSIBLE AS WELL. IFR/LIFR CIGS CONTINUE WITH OCCASIONAL VARIABILITY BUT EXPECT THAT STEADY IFR/LIFR WILL PREVAIL THROUGH THE NIGHT. THE BULK OF THE RAIN WILL EXIT FROM WEST TO EAST THROUGH MID EVENING AS A COOL FRONTAL BOUNDARY APPROACHES FROM THE WEST. VSBY TRENDS BECOME THE MAIN CONCERN FROM MID EVENING THROUGH MUCH OF TONIGHT AS WARMER AND MORE MOIST AIR LIFTS INTO THE AREA BEHIND THE WARM FRONT AND AHEAD OF THE COLD FRONT. CURRENT OBS SHOW VSBY OF 3/4SM OR LESS ACROSS MUCH OF CENTRAL/EASTERN IOWA AND NORTH CENTRAL MISSOURI. WITH THE LOW LIFTING NORTHEAST THIS LOWEST VSBY MAY BE DRAGGED NORTHEAST TO THE POINT WHERE THE WORST OF IT REMAINS WEST OF THE TERMINALS. WITH WARMER AND MORE MOIST AIR APPROACHING DO EXPECT THAT VSBY WILL FALL THIS EVENING BUT AM NOT SURE THAT IT WILL RESULT IN DENSE FOG. WILL CONTINUE WITH 1SM FOR NOW AND MONITOR OBS OVER THE NEXT FEW HOURS TO DETERMINE OF ANY LOWERING IS NEEDED. OTHERWISE SOME LIGHT RAIN OR DRIZZLE WILL LIKELY CONTINUE INTO THE OVERNIGHT. WINDS WILL TURN SOUTH-SOUTHWEST THIS EVENING. THE COLD FRONT WILL PASS OVERNIGHT TURNING WINDS WESTERLY AND ALLOW SOME LOW LEVEL DRYING TO OCCUR. THIS SHOULD ALLOW VSBY TO MARKEDLY IMPROVE PRIOR TO DAYBREAK BUT CEILINGS WILL LIKELY REMAIN IFR THROUGH AT LEAST SOME OF THE MORNING HOURS. AN IMPROVEMENT TO MVFR IS EXPECTED...WITH SCATTERING POSSIBLE LATER IN THE DAY. WILL NEED TO MONITOR THE POTENTIAL FOR SOME SNOW SHOWERS JUST AFTER DAYBREAK AS AN UPPER LEVEL TROUGH PASSES...BUT THIS LOOK TO OCCUR OVER A SHORT PERIOD. MDB //ORD AND MDW CONFIDENCE...UPDATED 00Z... * HIGH CONFIDENCE IN VSBY TRENDS WITH RAINFALL THROUGH EARLY EVENING. * LOW-MEDIUM CONFIDENCE IN VSBY REDUCTION MID/LATE EVENING...LOW CONFIDENCE IN HOW LOW VSBY MAY FALL. * HIGH CONFIDENCE IN IFR/LIFR CIGS THROUGH TONIGHT...MEDIUM CONFIDENCE IN HOW QUICKLY THEY IMPROVE SATURDAY MORNING. * LOW CONFIDENCE IN SNOW SHOWER POTENTIAL SATURDAY MORNING. * HIGH CONFIDENCE IN WIND TRENDS. MDB //OUTLOOK FOR ORD/MDW FOR 12Z SUNDAY-12Z FRIDAY...UPDATED 00Z... SUNDAY...STRONG SOUTH WINDS...LLWS POSSIBLE AFTERNOON/EARLY EVENING. VFR PROBABLE. MONDAY...VFR. TUESDAY...CHANCE OF SNOW/IFR. WEDNESDAY AND THURSDAY...VFR PROBABLE. MDB && .MARINE... 209 PM CST LARGE DOME OF HIGH PRESSURE OVER THE EASTERN SEABOARD HAS DRIFTED EAST...AND STRETCHES FROM CENTRAL QUEBEC SOUTH THROUGH THE CAROLINA COAST. MEANWHILE ACROSS THE CENTRAL PLAINS A SERIES OF LOW PRESSURES EXISTED...WITH ONE ACROSS THE NORTHERN PLAINS AND THE SECOND ACROSS THE CENTRAL PLAINS. THESE TWO AREAS OF LOW PRESSURES WILL CONVERGE UPON LAKE MICHIGAN...CONSOLIDATING INTO A SLIGHTLY STRONGER LOW PRESSURE OVER THE NORTHERN PORTION OF LAKE MICHIGAN EARLY SATURDAY MORNING. WINDS FOR MUCH OF THE LAKE WILL REMAIN SOUTHERLY...WITH THE FAR NORTHERN PORTIONS NEAR THE STRAITS OF MACKINAW BEING SLIGHTLY SOUTHEAST/EAST. THEN WITH THE LOW PASSAGE EXPECTED TO OCCUR SATURDAY MORNING WITH A TRAILING FRONTAL BOUNDARY SLIDING EAST ACROSS THE LAKE...THE GRADIENT IS EXPECTED TO TIGHTEN. FOR THE CENTRAL/SOUTHERN PORTIONS WINDS WILL INCREASE TO NEAR 30 KT BY MIDDAY/EARLY AFTN SAT. THEN AS THE FRONTAL BOUNDARY CONTINUES TO PRESS EAST...WINDS WILL TURN MORE TO THE WEST. FOR THE NORTHERN HALF OF THE LAKE WINDS FOR A PERIOD WILL BECOME NORTHWEST...BEFORE RELAXING TO THE WEST SAT LATE AFTN. HIGH PRESSURE ACROSS THE SOUTHERN PLAINS SAT AFTN WILL CONTINUE TO SLIDE EAST...STRETCHING AN INFLUENCE NORTH TO LAKE MICHIGAN SATURDAY NIGHT/EARLY SUN. THIS COUPLED WITH YET ANOTHER LOW PRESSURE SYSTEM BEGINNING TO PUSH INTO CENTRAL CANADA...WILL ALLOW THE GRADIENT TO TIGHTEN. WINDS SHOULD REMAIN BREEZY SUN AFTN/EVE. THE GRADIENT HAS BECOME SLIGHTLY TIGHTER...ALONG WITH THE LOW PRESSURE BECOME DEEPER TO 28.9 INCHES JUST NORTH OF LAKE SUPERIOR SUN EVE. THIS WILL LIKELY CREATE A PERIOD OF GALES FOR THE LAKE DURING THE SUN AFTN/EVE TIMEFRAME. THE GRADIENT THEN BEGINS TO SLACKEN OFF FOR THE MIDDLE OF NEXT WEEK...WITH JUST A COUPLE WEAK WAVES TRAVERSING THE WESTERN GREAT LAKES REGION. IN THE LONGER RANGE PERIODS FORECAST GUIDANCE IS BEGINNING TO INDICATE A STRENGTHENING LOW PRESSURE OVER THE OHIO VALLEY TUE NIGHT...WHICH COULD RESULT IN A TIGHTENING GRADIENT FOR LAKE MICHIGAN WED AND BREEZY CONDITIONS RETURNING. BEACHLER && .LOT WATCHES/WARNINGS/ADVISORIES... IL...FREEZING RAIN ADVISORY...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008- ILZ010-ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021- ILZ022 UNTIL MIDNIGHT SATURDAY. IN...NONE. LM...NONE. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
610 PM CST FRI JAN 10 2014 .DISCUSSION... 326 PM CST THE RAPIDLY EVOLVING NEXT 18 TO 24 HOURS APPEAR TO BE THE MOST CHALLENGING PORTION OF THE FORECAST FOR THE WEEKEND INTO NEXT WEEK. ISOLATED THUNDERSTORMS HAVE MOVED INTO THE AREA THIS AFTERNOON AND SUBFREEZING TEMPERATURES HAVE FOR THE MOST PART MOVED OUT...AT LEAST FOR THE TIME BEING. THE PRIMARY FORECAST CONCERNS IN THE NEAR TERM INCLUDE DENSE FOG AND THE POSSIBLE NEED FOR AN ADVISORY LATER TONIGHT...THUNDERSTORM TRENDS AND COVERAGE...AND THE FLOOD POTENTIAL GIVEN THE EXPECTED RAINFALL AND WARMING TEMPERATURES. AS MENTIONED IN THE MORNING AFD UPDATE...THE FIRST QUESTION WOULD BE WHETHER DENSE FOG DEVELOPS IN THE SATURATED SURFACE LAYER MOVING IN OVER THE SNOWPACK WITH INCREASING DEWPOINTS. OBSERVATIONS JUST UPSTREAM OF THE AREA ARE SHOWING VSBYS AT WORST AROUND 1 MILE AND GENERALLY QUITE A BIT HIGHER...BUT FARTHER WEST AND SOUTHWEST TOWARD THE APPROACHING LOW CENTER THEY ARE MORE COMMONLY AROUND 1/4 TO 1/2 MILE. STILL AM NOT ANTICIPATING THE NEED FOR FOG HEADLINES IN THE IMMEDIATE TERM. WINDS IN THE TEENS AND MODERATE RAIN ACTUALLY SEEM TO BE HELPING THINGS AS WELL...BUT THE EVENING SHIFT WILL NEED TO REEVALUATE IN CASE CONDITIONS DETERIORATE AND A HEADLINE BECOMES NECESSARY LATE THIS EVENING OR OVERNIGHT. THE AREA OF THUNDERSTORMS SEEN EARLIER TODAY AROUND QUINCY HAS NOW MOVED INTO THE LOCAL AREA AS ANTICIPATED...IN CONJUNCTION WITH THE INCREASING LOW LEVEL MOISTURE FLUX DEPICTED IN THE RAP MODEL EAST OF THE APPROACHING LOW PRESSURE CENTER. AM NOT SEEING ANYTHING TO SUGGEST THIS ACTIVITY WILL BECOME WIDESPREAD THIS EVENING AS THE LOW LIFTS NORTHEAST...BUT WILL MAINTAIN A FIRST PERIOD MENTION OF ISOLATED TO SCATTERED THUNDERSTORMS MAINLY FOR THE SOUTHERN HALF OF THE AREA. AS FOR FLOODING POTENTIAL...HAVE BEEN CONSIDERING A FLOOD ADVISORY FOR URBAN AREAS WHERE RAIN MAY BE PONDING DUE TO DRAINS CLOGGED WITH ICE AND SNOW. AM NOT PLANNING ON ANY AREAL FLOOD WARNING HEADLINES AT THIS TIME GIVEN SO MANY VARIABLES...INCLUDING LOCATION OF HEAVIER RAIN AMOUNTS...DEGREE TO WHICH THE SNOWPACK WOULD SPONGE UP THE RAIN...EVOLUTION OF DEWPOINT TEMPERATURES...AND THE BEHAVIOR OF ICE ON THE RIVERS AND STREAMS. THE BEST POTENTIAL FOR MAINSTEM FLOODING STILL APPEARS TO BE LIMITED TO THE KANKAKEE WHERE A FLOOD WARNING WAS ISSUED EARLIER FOR ANTICIPATED MINOR FLOODING. THE OTHER RIVERS HAVE A LITTLE MORE ROOM TO HANDLE THE RUNOFF. FOR TONIGHT INTO TOMORROW MORNING...MAY TWEAK THE TIMING A BIT BUT AM NOT PLANNING ANY BIG CHANGES TO PRECIPITATION TRENDS. STILL EXPECTING MAINLY RAIN OVERNIGHT...EVOLVING TO DRIZZLE AND MAYBE A PERIOD OF LIGHT SNOW AS COLD AIR MOVES IN TOWARD MORNING. THE REMAINDER OF THE WEEKEND LOOKS DRY AND RELATIVELY MILD WITH SOUTHERLY WINDS AND CLEARING SKIES SUNDAY. NEXT WEEK BRINGS A RETURN TO SOMEWHAT MORE SEASONABLE...THOUGH STILL BELOW NORMAL...TEMPERATURES AND MULTIPLE PERIODS OF LIGHT SNOW POTENTIAL CORRESPONDING TO COLD FRONTAL PASSAGES. THE PRIMARY SURFACE CYCLONE TRACK APPEARS TO STAY NORTH OF THE LOCAL AREA. THE MOST PRONOUNCED COLD AIR INTRUSION LOOKS POISED TO ARRIVE LATE IN THE WEEK...POTENTIALLY KEEPING HIGHS ONLY IN THE TEENS NEXT FRIDAY. LENNING && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 00Z... * VARIABLE VSBY BETWEEN AROUND 2 AND 5SM IN RAIN THROUGH EARLY/MID EVENING. VSBY REDUCTION DOWN TO AROUND 1SM POSSIBLE MID/LATE EVENING AS RAIN DIMINISHES...LOWER VSBY POSSIBLE. * IFR/LIFR CIGS CONTINUING THROUGH SATURDAY MORNING WITH IMPROVEMENT TO MVFR EXPECTED TOWARD MIDDAY. * SCATTERED SNOW SHOWERS POSSIBLE FOR A SHORT TIME AFTER SUNRISE. * SOUTH-SOUTHEAST WINDS TURNING SOUTH-SOUTHWEST MID EVENING...THEN WESTERLY OVERNIGHT. MDB //DISCUSSION...UPDATED 00Z... LOW PRESSURE CONTINUES TO MOVE NORTHEAST ACROSS SOUTHERN IOWA WITH A WARM FRONT MOVING NORTHWARD TOWARD THE TERMINALS. RAIN WILL CONTINUE ACROSS THE TERMINALS FOR THE NEXT FEW HOURS WITH VARIATIONS IN VSBY WITH OBS SHOWING VALUES IN THE 2-4SM RANGE WITH SOME SPOTTY 1SM VSBY POSSIBLE AS WELL. IFR/LIFR CIGS CONTINUE WITH OCCASIONAL VARIABILITY BUT EXPECT THAT STEADY IFR/LIFR WILL PREVAIL THROUGH THE NIGHT. THE BULK OF THE RAIN WILL EXIT FROM WEST TO EAST THROUGH MID EVENING AS A COOL FRONTAL BOUNDARY APPROACHES FROM THE WEST. VSBY TRENDS BECOME THE MAIN CONCERN FROM MID EVENING THROUGH MUCH OF TONIGHT AS WARMER AND MORE MOIST AIR LIFTS INTO THE AREA BEHIND THE WARM FRONT AND AHEAD OF THE COLD FRONT. CURRENT OBS SHOW VSBY OF 3/4SM OR LESS ACROSS MUCH OF CENTRAL/EASTERN IOWA AND NORTH CENTRAL MISSOURI. WITH THE LOW LIFTING NORTHEAST THIS LOWEST VSBY MAY BE DRAGGED NORTHEAST TO THE POINT WHERE THE WORST OF IT REMAINS WEST OF THE TERMINALS. WITH WARMER AND MORE MOIST AIR APPROACHING DO EXPECT THAT VSBY WILL FALL THIS EVENING BUT AM NOT SURE THAT IT WILL RESULT IN DENSE FOG. WILL CONTINUE WITH 1SM FOR NOW AND MONITOR OBS OVER THE NEXT FEW HOURS TO DETERMINE OF ANY LOWERING IS NEEDED. OTHERWISE SOME LIGHT RAIN OR DRIZZLE WILL LIKELY CONTINUE INTO THE OVERNIGHT. WINDS WILL TURN SOUTH-SOUTHWEST THIS EVENING. THE COLD FRONT WILL PASS OVERNIGHT TURNING WINDS WESTERLY AND ALLOW SOME LOW LEVEL DRYING TO OCCUR. THIS SHOULD ALLOW VSBY TO MARKEDLY IMPROVE PRIOR TO DAYBREAK BUT CEILINGS WILL LIKELY REMAIN IFR THROUGH AT LEAST SOME OF THE MORNING HOURS. AN IMPROVEMENT TO MVFR IS EXPECTED...WITH SCATTERING POSSIBLE LATER IN THE DAY. WILL NEED TO MONITOR THE POTENTIAL FOR SOME SNOW SHOWERS JUST AFTER DAYBREAK AS AN UPPER LEVEL TROUGH PASSES...BUT THIS LOOK TO OCCUR OVER A SHORT PERIOD. MDB //ORD AND MDW CONFIDENCE...UPDATED 00Z... * HIGH CONFIDENCE IN VSBY TRENDS WITH RAINFALL THROUGH EARLY EVENING. * LOW-MEDIUM CONFIDENCE IN VSBY REDUCTION MID/LATE EVENING...LOW CONFIDENCE IN HOW LOW VSBY MAY FALL. * HIGH CONFIDENCE IN IFR/LIFR CIGS THROUGH TONIGHT...MEDIUM CONFIDENCE IN HOW QUICKLY THEY IMPROVE SATURDAY MORNING. * LOW CONFIDENCE IN SNOW SHOWER POTENTIAL SATURDAY MORNING. * HIGH CONFIDENCE IN WIND TRENDS. MDB //OUTLOOK FOR ORD/MDW FOR 12Z SUNDAY-12Z FRIDAY...UPDATED 00Z... SUNDAY...STRONG SOUTH WINDS...LLWS POSSIBLE AFTERNOON/EARLY EVENING. VFR PROBABLE. MONDAY...VFR. TUESDAY...CHANCE OF SNOW/IFR. WEDNESDAY AND THURSDAY...VFR PROBABLE. MDB && .MARINE... 209 PM CST LARGE DOME OF HIGH PRESSURE OVER THE EASTERN SEABOARD HAS DRIFTED EAST...AND STRETCHES FROM CENTRAL QUEBEC SOUTH THROUGH THE CAROLINA COAST. MEANWHILE ACROSS THE CENTRAL PLAINS A SERIES OF LOW PRESSURES EXISTED...WITH ONE ACROSS THE NORTHERN PLAINS AND THE SECOND ACROSS THE CENTRAL PLAINS. THESE TWO AREAS OF LOW PRESSURES WILL CONVERGE UPON LAKE MICHIGAN...CONSOLIDATING INTO A SLIGHTLY STRONGER LOW PRESSURE OVER THE NORTHERN PORTION OF LAKE MICHIGAN EARLY SATURDAY MORNING. WINDS FOR MUCH OF THE LAKE WILL REMAIN SOUTHERLY...WITH THE FAR NORTHERN PORTIONS NEAR THE STRAITS OF MACKINAW BEING SLIGHTLY SOUTHEAST/EAST. THEN WITH THE LOW PASSAGE EXPECTED TO OCCUR SATURDAY MORNING WITH A TRAILING FRONTAL BOUNDARY SLIDING EAST ACROSS THE LAKE...THE GRADIENT IS EXPECTED TO TIGHTEN. FOR THE CENTRAL/SOUTHERN PORTIONS WINDS WILL INCREASE TO NEAR 30 KT BY MIDDAY/EARLY AFTN SAT. THEN AS THE FRONTAL BOUNDARY CONTINUES TO PRESS EAST...WINDS WILL TURN MORE TO THE WEST. FOR THE NORTHERN HALF OF THE LAKE WINDS FOR A PERIOD WILL BECOME NORTHWEST...BEFORE RELAXING TO THE WEST SAT LATE AFTN. HIGH PRESSURE ACROSS THE SOUTHERN PLAINS SAT AFTN WILL CONTINUE TO SLIDE EAST...STRETCHING AN INFLUENCE NORTH TO LAKE MICHIGAN SATURDAY NIGHT/EARLY SUN. THIS COUPLED WITH YET ANOTHER LOW PRESSURE SYSTEM BEGINNING TO PUSH INTO CENTRAL CANADA...WILL ALLOW THE GRADIENT TO TIGHTEN. WINDS SHOULD REMAIN BREEZY SUN AFTN/EVE. THE GRADIENT HAS BECOME SLIGHTLY TIGHTER...ALONG WITH THE LOW PRESSURE BECOME DEEPER TO 28.9 INCHES JUST NORTH OF LAKE SUPERIOR SUN EVE. THIS WILL LIKELY CREATE A PERIOD OF GALES FOR THE LAKE DURING THE SUN AFTN/EVE TIMEFRAME. THE GRADIENT THEN BEGINS TO SLACKEN OFF FOR THE MIDDLE OF NEXT WEEK...WITH JUST A COUPLE WEAK WAVES TRAVERSING THE WESTERN GREAT LAKES REGION. IN THE LONGER RANGE PERIODS FORECAST GUIDANCE IS BEGINNING TO INDICATE A STRENGTHENING LOW PRESSURE OVER THE OHIO VALLEY TUE NIGHT...WHICH COULD RESULT IN A TIGHTENING GRADIENT FOR LAKE MICHIGAN WED AND BREEZY CONDITIONS RETURNING. BEACHLER && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...NONE. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
256 AM CST THU JAN 9 2014 .DISCUSSION... 915 PM CST NO MAJOR CHANGES TO THE GOING FORECAST THIS EVENING. MAINLY ADJUSTED HOURLY TEMP TRENDS BUT DID LOWER MINS A FEW DEGREES ACROSS THE NORTHERN HALF OF THE CWA...ESPECIALLY FAR NORTH...WHICH LOOKS TO SEE THE LEAST CLOUD COVER THROUGH THE NIGHT. ALSO REMOVED THE SLIGHT POP IN THE FAR SOUTH AS FGEN THAT HAD DRIVEN SOME LIGHT SNOW EARLIER HAS FADED LEAVING ONLY CLOUD COVER BEHIND...WHICH SHOULD SHIFT NORTHWARD LATER TONIGHT. MDB //PREV DISCUSSION... 335 PM CST MAIN FORECAST CHALLENGES/CONCERNS ARE WITH ONE MORE COLD SUBZERO NIGHT TONIGHT...SNOW AND FREEZING DRIZZLE CHANCES THURSDAY AND THURSDAY NIGHT...WITH VARYING PRECIP TYPE LINGERING INTO FRIDAY MORNING BEFORE WARMING TEMPS PROVIDE RAIN THROUGH EARLY SATURDAY. OF CONCERN IN THE NEAR TERM IS THE NARROW BAND OF SNOW WHICH DEVELOPED THIS PAST AFTERNOON PRIMARILY SOUTH OF A LINE FROM PONTIAC TO RENSSELAER. THIS SNOW WAS IN RESPONSE TO THE ANTICIPATED MID LEVEL FEATURE TRAVERSING THE REGION...WITH ASSOCIATED MID LEVEL FRONTOGENESIS AIDING IN THIS LIFT. DECENT RETURNS ON RADAR HAVE CONTINUE TO BE OBSERVED AND WOULD SUSPECT THAT VIS IS GENERALLY STAYING IN THE 1 TO 3 MILE RANGE...AS SAMPLING OF THIS SNOW FROM SURFACE OBS HAS BEEN LACKING. WITH THIS WAVE SLOWLY DEPARTING THIS EVENING...EXPECT THE OVERALL LARGE SCALE LIFT TO WEAKEN WHILE THE FRONTOGENESIS AXIS WEAKENS WHILE ALSO EXITING...WITH LATEST RAP ANALYSIS ALREADY SHOWING THIS WEAKENING TREND. ALTHOUGH 1 TO 3 MILE VIS IN THIS SNOW IS STILL EXPECTED AT LEAST THROUGH THE NEXT 1 TO 3 HOURS...COULD EASILY SEE VIS BRIEFLY DROPPING TO UNDER 1 MILE AT TIMES. HAVE LIKELY POPS TO REFLECT CURRENT CONDITIONS IN THIS AREA LATE THIS AFTERNOON TRENDING TOWARDS CHANCE POPS AND THEN SLIGHT CHANCE POPS THIS EVENING...WITH SNOW AMOUNTS BY THE TIME THIS DEPARTS COULD BE IN THE HALF INCH TO INCH RANGE. AFTER ANY LINGER SNOW DEPARTS THIS EVENING...WILL SHIFT ATTENTION BACK TOWARDS TEMPS TONIGHT. VORT MAX TO THE NORTH/NORTHEAST AND IMPULSE TO THE SOUTH WILL CONTINUE TO DEPART OVERNIGHT WITH SURFACE RIDGING CONTINUING OVER THE AREA. WITH THIS OCCURRING...IT DOES APPEAR THAT THE CENTER OF THIS SURFACE HIGH WILL SETTLE IN ACROSS THE AREA OVERNIGHT. DESPITE CONTINUED MODERATION OF THIS COLD AIR MASS TONIGHT...DEPARTING MID/HIGH LEVEL CLOUD COVER TO THE SOUTH AND THIS HIGH OVERHEAD WILL ALLOW FOR A GREAT RADIATIONAL COOLING NIGHT...ESPECIALLY WITH THE CURRENT SNOWPACK IN PLACE. HAVE FURTHER LOWERED TEMPS TONIGHT AND AM NOW EXPECTING LOW TEMPS TO DROP TO ZERO OR BELOW ZERO FOR MOST LOCATIONS IN THIS CLOUD FREE SKY...WHICH AT THIS TIME IS FOR AREAS ALONG AND NORTH OF I-80. COLDEST TEMPS OF 10 TO 12 BELOW ZERO ARE ANTICIPATED ACROSS NORTH CENTRAL ILLINOIS...AND CLOSER TO THE WISCONSIN BORDER. WITH THE SURFACE HIGH IN PLACE...WINDS WILL BE ON THE LIGHT SIDE IF NOT CALM TONIGHT AND DONT ANTICIPATE WIND CHILLS TO STRAY TOO FAR FROM LOW TEMPS TONIGHT...AND FOR ANY EXTENDED PERIOD OF TIME. ALTHOUGH...SPORADIC HIGHER WIND SPEEDS COULD STILL YIELD SLIGHTLY LOWER WIND CHILLS OF 5 TO 15 BELOW ZERO BRIEFLY OVERNIGHT. ALTHOUGH EARLY THURSDAY MORNING WILL START OFF DRY...THE CONTINUED ACTIVE PATTERN WILL USHER IN ANOTHER STRONGER AND MORE DEFINED MID LEVEL WAVE ACROSS THE PLAINS AND MID MISSISSIPPI VALLEY. AS THIS WAVE APPROACHES...ALREADY BACKED WINDS AND ONGOING WAA WILL BRING A SWATH OF PRECIP NORTH/NORTHEAST ACROSS CENTRAL ILLINOIS THROUGH MID DAY...AND THEN CONTINUING NORTH INTO PORTIONS OF NORTHERN ILLINOIS AND NORTHWEST INDIANA AS THIS WAVE AND BROAD SCALE LIFT PUSH NORTHEAST. MODEL GUIDANCE IS IN PRETTY GOOD AGREEMENT FOR AREAS ACROSS THE SOUTHEAST HALF OF THE CWA TO OBSERVE THIS PRECIP...WITH GUIDANCE VARYING TO THE FURTHER NORTHWARD EXTENT OF THIS PRECIP SHIELD. HAVE INCREASE POPS TO LIKELY ACROSS THE SOUTHEAST...AND MAINTAINED CHANCE POPS THROUGH THE REMAINING CWA THURSDAY AFTERNOON. THERMAL PROFILE WILL NEED TO BE CAREFULLY EVALUATED THURSDAY AFTERNOON INTO THURSDAY EVENING...AS ALTHOUGH THE COLUMN WILL BE SUFFICIENT FOR SNOW...THE EXTENT OF THE DEEPER MOISTURE/CRYSTALS IS STILL SOMEWHAT UNCERTAIN. THIS UNCERTAINTY IS ESPECIALLY THE CASE FOR AREAS ACROSS NORTHWEST AND NORTH CENTRAL ILLINOIS WHERE ITS POSSIBLE THAT THIS PRECIP WILL START OFF AS MIX OF SNOW OR FREEZING DRIZZLE. AREAS TO THE SOUTH AND SOUTHEAST...ACROSS NORTHEAST ILLINOIS AND NORTHWEST INDIANA...COULD OBSERVE THIS MIX INITIALLY BUT WITH A HIGHER LIKELIHOOD FOR THIS PRECIP TO BE IN THE FORM OF ALL SNOW. THEN AREAS IN EAST CENTRAL ILLINOIS AND NORTHWEST INDIANA WILL OBSERVE ALL SNOW DURING THIS PERIOD. THIS VARYING PRECIP TYPE FROM FREEZING DRIZZLE WILL LIKELY CONTINUE INTO THURSDAY EVENING...WITH BETTER CHANCES FOR FREEZING DRIZZLE GOING INTO THE OVERNIGHT HOURS. HAVE A HALF INCH TO AN INCH OF WET SNOW FORECAST FOR THURSDAY AFTERNOON INTO THE EVENING FOR AREAS SOUTH AND SOUTHEAST OF I-88...WITH HIGHER SNOW AMOUNTS THE FURTHER SOUTHEAST. HAVE NOT MADE MENTION OF ANY ICE ACCUMULATION IN THE GRIDS...BUT THIS IS SOMETHING ALSO NEEDED TO BE MONITORED. ALTHOUGH ANY FREEZING DRIZZLE IS EXPECTED TO BE LIGHT...MINOR ICE ACCUMULATION COULD BE OBSERVED AND ESPECIALLY IF THIS FREEZING DRIZZLE PERSISTS INTO THURSDAY NIGHT. ONGOING WAA WILL FURTHER STRENGTHEN INTO FRIDAY WITH SCATTERED LIGHT PRECIP EXPECTED TO SPREAD NORTH ACROSS THE AREA FRIDAY MORNING. FURTHER WARMING OF THIS COLUMN WILL YIELD LIQUID PRECIP...BUT WITH SURFACE TEMPS FORECAST TO BE IN THE UPPER 20S. THIS IS ANOTHER PERIOD TO KEEP AN EYE ON WITH A PERIOD OF FREEZING RAIN POSSIBLE...ESPECIALLY IF THE BETTER PRECIP AXIS PUSHES NORTH BEFORE TEMPS RISE ABOVE FREEZING BY MID DAY FRIDAY. HAVE INCREASED POPS SIGNIFICANTLY FRIDAY INTO FRIDAY NIGHT AS GUIDANCE IS IN GOOD AGREEMENT FOR AN EXTENDED PERIOD OF LIGHT TO MODERATE RAIN TO FALL. YET ANOTHER PERIOD OF REINFORCING LIFT OWING TO A HIGHLY AMPLIFIED MID/UPPER LEVEL TROUGH AND ATTENDANT SURFACE LOW. ALONG WITH THIS LIFT...THIS APPROACHING SYSTEM WILL ALLOW FOR A WARMER AND MOIST ENVIRONMENT TO MOVE NORTHWARD DURING THIS PERIOD. RESULTANT RAINFALL AMOUNTS FROM FRIDAY AFTERNOON THROUGH EARLY SATURDAY MORNING WILL BE AROUND 1 INCH AND POSSIBLY HIGHER IN SOME LOCATIONS. THIS RAINFALL COINCIDING WITH THE CURRENT SNOWPACK COULD RAISE SOME ISSUES WITH REGARDS TO AREA RIVERS AND CREEKS...WITH RISES EXPECTED. ALSO...THIS RAIN AND SLIGHT WARMING WILL CREATE A SETUP FOR ICE JAM FLOODING TO BECOME MORE OF AN ISSUE. WILL CONTINUE TO MENTION THIS ASPECT IN THE HWO...WITH AN ESF LIKELY ISSUED OVERNIGHT TONIGHT OR TOMORROW. RODRIGUEZ && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 09Z... * PRECIP OVERSPREADING THE TERMINALS THIS AFTERNOON...INITIALLY LIGHT SNOW...THEN SWITCHING OVER TO FREEZING DRIZZLE BY EARLY EVENING. * CIGS/VIS LOWERING TO MVFR BY THIS AFTERNOON...AND CIGS LOWERING IFR THURSDAY EVENING. KREIN //DISCUSSION...UPDATED 06Z... AS HIGH PRESSURE BUILDS ACROSS THE REGION...CONDITIONS WILL REMAIN VFR WITH CALM TO LGT/VRBL WINDS INTO LATE THURSDAY MORNING. BY THEN...THE HGI WILL SHIFT OFF TO THE EAST AND WINDS WILL BECOME SELY-SSELY AND INCREASE...BUT REMAIN UNDER 10KT. A MID LEVEL DISTURBANCE LIFTING FROM THE SOUTHWEST WILL BRING LOWERING CIGS AND SOME LIGHT PCPN. WITH TEMPERATURES EXPECTED TO REMAIN BELOW FREEZING THROUGH THE DAY...AND WITH A SATURATED LAYER EXPECTED TO EXTEND TO 15KFT...INITIAL PCPN SHOULD BE LIGHT SNOW...THOUGH IF THE MOIST LAYER IS NOT QUITE THAT DEEP...PCPN COULD START OUT AS SOME LIGHT FREEZING DRIZZLE. HOWEVER...THE MOISTURE PROFILE GUIDANCE INDICATES THAT THE TOP OF THE MOIST LAYER WILL LOWER WITH TIME THROUGH THE AFTERNOON...AND BY EVENING THE MOIST LAYER WILL NO LONGER BE DEEP ENOUGH TO SUPPORT ICE PRODUCTION AND ANY LINGERING PCPN SHOULD CHANGE OVER TO LIGHT FREEZING DRIZZLE. WITH THE ONSET OF THE PCPN...VIS SHOULD LOWER TO MVFR LEVELS...BUT CIGS SHOULD GRADUALLY LOWER THROUGH MVFR TO IFR LEVELS INTO THE EVENING...WITH IFR CONDITIONS LIKELY PERSISTING THROUGH THE NIGHT. KREIN //ORD AND MDW CONFIDENCE...UPDATED 09Z... * MEDIUM CONFIDENCE IN TIMING OF ONSET OF PCPN. * MEDIUM CONFIDENCE IN PCPN STARTING AS -SN AND THEN CHANGING OVER TO -FZDZ BY EARLY EVENING...WITH LOW CONFIDENCE IN THE TIMING OF THE CHANGE OVER. * HIGH CONFIDENCE WIND TRENDS. * HIGH CONFIDENCE ON CIG TRENDS THURSDAY AFTERNOON AND EVENING... BUT LOWER CONFIDENCE IN THE EXACT TIMING OF THE CATAGORY CHANGES. KREIN //OUTLOOK FOR ORD/MDW FOR 12Z FRIDAY-12Z WEDNESDAY...UPDATED 00Z... FRIDAY...WINTRY MIX EARLY...BECOMING ALL RAIN. MVFR/IFR LIKELY. SATURDAY...CHANCE OF RAIN OR SNOW WITH IFR/MVFR DURING THE DAY. SUNDAY...SLIGHT CHANCE OF RAIN OR SNOW LATE. MVFR POSSIBLE. MONDAY...MVFR POSSIBLE. TUESDAY...SLIGHT CHANCE OF SNOW. MVFR POSSIBLE. KJB && .MARINE... 300 AM CST CONDITIONS OVER THE LAKE WILL START OUT RELATIVELY QUIET TODAY...AS A LARGE AREA OF HIGH PRESSURE CENTERED OVER PENNSYLVANIA SLOWLY SLIDES EAST AS A TROUGH OF LOW PRESSURE DEVELOPS OVER THE NORTHERN PLAINS. THE HIGH WILL SLOWLY CONTINUE TO BUILD TO THE EAST...BUT SLOWER THAN THE TROUGH OVER THE PLAINS DEEPENS AS TRACKS EAST AS WELL...LEADING TO STRENGTHENING SOUTH WINDS OVER THE LAKE. IN THE MEANTIME...LOW PRESSURE IS EXPECTED TO DEVELOP OVER OKLAHOMA FRIDAY MORNING...TRACK NORTHEAST TO LAKE MICHIGAN BY SATURDAY MORNING WHILE RAPIDLY DEEPENING. THE LOW WILL CONTINUE TO THE NORTHEAST...DRAGGING A STRONG COLD FRONT ACROSS THE LAKE LATE FRIDAY NIGHT...QUICKLY SHIFTING WINDS TO WESTERLY. THE AMOUNT OF ICE REMAINS HIGH ACROSS NEARSHORE WATERS AS SEEN IN WEBCAMS AND SATELLITE IMAGERY. THUS WAVES WILL BE OMITTED FROM THE NEARSHORE FORECAST. KREIN && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...NONE. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1152 PM CST WED JAN 8 2014 .DISCUSSION... 915 PM CST NO MAJOR CHANGES TO THE GOING FORECAST THIS EVENING. MAINLY ADJUSTED HOURLY TEMP TRENDS BUT DID LOWER MINS A FEW DEGREES ACROSS THE NORTHERN HALF OF THE CWA...ESPECIALLY FAR NORTH...WHICH LOOKS TO SEE THE LEAST CLOUD COVER THROUGH THE NIGHT. ALSO REMOVED THE SLIGHT POP IN THE FAR SOUTH AS FGEN THAT HAD DRIVEN SOME LIGHT SNOW EARLIER HAS FADED LEAVING ONLY CLOUD COVER BEHIND...WHICH SHOULD SHIFT NORTHWARD LATER TONIGHT. MDB //PREV DISCUSSION... 335 PM CST MAIN FORECAST CHALLENGES/CONCERNS ARE WITH ONE MORE COLD SUBZERO NIGHT TONIGHT...SNOW AND FREEZING DRIZZLE CHANCES THURSDAY AND THURSDAY NIGHT...WITH VARYING PRECIP TYPE LINGERING INTO FRIDAY MORNING BEFORE WARMING TEMPS PROVIDE RAIN THROUGH EARLY SATURDAY. OF CONCERN IN THE NEAR TERM IS THE NARROW BAND OF SNOW WHICH DEVELOPED THIS PAST AFTERNOON PRIMARILY SOUTH OF A LINE FROM PONTIAC TO RENSSELAER. THIS SNOW WAS IN RESPONSE TO THE ANTICIPATED MID LEVEL FEATURE TRAVERSING THE REGION...WITH ASSOCIATED MID LEVEL FRONTOGENESIS AIDING IN THIS LIFT. DECENT RETURNS ON RADAR HAVE CONTINUE TO BE OBSERVED AND WOULD SUSPECT THAT VIS IS GENERALLY STAYING IN THE 1 TO 3 MILE RANGE...AS SAMPLING OF THIS SNOW FROM SURFACE OBS HAS BEEN LACKING. WITH THIS WAVE SLOWLY DEPARTING THIS EVENING...EXPECT THE OVERALL LARGE SCALE LIFT TO WEAKEN WHILE THE FRONTOGENESIS AXIS WEAKENS WHILE ALSO EXITING...WITH LATEST RAP ANALYSIS ALREADY SHOWING THIS WEAKENING TREND. ALTHOUGH 1 TO 3 MILE VIS IN THIS SNOW IS STILL EXPECTED AT LEAST THROUGH THE NEXT 1 TO 3 HOURS...COULD EASILY SEE VIS BRIEFLY DROPPING TO UNDER 1 MILE AT TIMES. HAVE LIKELY POPS TO REFLECT CURRENT CONDITIONS IN THIS AREA LATE THIS AFTERNOON TRENDING TOWARDS CHANCE POPS AND THEN SLIGHT CHANCE POPS THIS EVENING...WITH SNOW AMOUNTS BY THE TIME THIS DEPARTS COULD BE IN THE HALF INCH TO INCH RANGE. AFTER ANY LINGER SNOW DEPARTS THIS EVENING...WILL SHIFT ATTENTION BACK TOWARDS TEMPS TONIGHT. VORT MAX TO THE NORTH/NORTHEAST AND IMPULSE TO THE SOUTH WILL CONTINUE TO DEPART OVERNIGHT WITH SURFACE RIDGING CONTINUING OVER THE AREA. WITH THIS OCCURRING...IT DOES APPEAR THAT THE CENTER OF THIS SURFACE HIGH WILL SETTLE IN ACROSS THE AREA OVERNIGHT. DESPITE CONTINUED MODERATION OF THIS COLD AIR MASS TONIGHT...DEPARTING MID/HIGH LEVEL CLOUD COVER TO THE SOUTH AND THIS HIGH OVERHEAD WILL ALLOW FOR A GREAT RADIATIONAL COOLING NIGHT...ESPECIALLY WITH THE CURRENT SNOWPACK IN PLACE. HAVE FURTHER LOWERED TEMPS TONIGHT AND AM NOW EXPECTING LOW TEMPS TO DROP TO ZERO OR BELOW ZERO FOR MOST LOCATIONS IN THIS CLOUD FREE SKY...WHICH AT THIS TIME IS FOR AREAS ALONG AND NORTH OF I-80. COLDEST TEMPS OF 10 TO 12 BELOW ZERO ARE ANTICIPATED ACROSS NORTH CENTRAL ILLINOIS...AND CLOSER TO THE WISCONSIN BORDER. WITH THE SURFACE HIGH IN PLACE...WINDS WILL BE ON THE LIGHT SIDE IF NOT CALM TONIGHT AND DONT ANTICIPATE WIND CHILLS TO STRAY TOO FAR FROM LOW TEMPS TONIGHT...AND FOR ANY EXTENDED PERIOD OF TIME. ALTHOUGH...SPORADIC HIGHER WIND SPEEDS COULD STILL YIELD SLIGHTLY LOWER WIND CHILLS OF 5 TO 15 BELOW ZERO BRIEFLY OVERNIGHT. ALTHOUGH EARLY THURSDAY MORNING WILL START OFF DRY...THE CONTINUED ACTIVE PATTERN WILL USHER IN ANOTHER STRONGER AND MORE DEFINED MID LEVEL WAVE ACROSS THE PLAINS AND MID MISSISSIPPI VALLEY. AS THIS WAVE APPROACHES...ALREADY BACKED WINDS AND ONGOING WAA WILL BRING A SWATH OF PRECIP NORTH/NORTHEAST ACROSS CENTRAL ILLINOIS THROUGH MID DAY...AND THEN CONTINUING NORTH INTO PORTIONS OF NORTHERN ILLINOIS AND NORTHWEST INDIANA AS THIS WAVE AND BROAD SCALE LIFT PUSH NORTHEAST. MODEL GUIDANCE IS IN PRETTY GOOD AGREEMENT FOR AREAS ACROSS THE SOUTHEAST HALF OF THE CWA TO OBSERVE THIS PRECIP...WITH GUIDANCE VARYING TO THE FURTHER NORTHWARD EXTENT OF THIS PRECIP SHIELD. HAVE INCREASE POPS TO LIKELY ACROSS THE SOUTHEAST...AND MAINTAINED CHANCE POPS THROUGH THE REMAINING CWA THURSDAY AFTERNOON. THERMAL PROFILE WILL NEED TO BE CAREFULLY EVALUATED THURSDAY AFTERNOON INTO THURSDAY EVENING...AS ALTHOUGH THE COLUMN WILL BE SUFFICIENT FOR SNOW...THE EXTENT OF THE DEEPER MOISTURE/CRYSTALS IS STILL SOMEWHAT UNCERTAIN. THIS UNCERTAINTY IS ESPECIALLY THE CASE FOR AREAS ACROSS NORTHWEST AND NORTH CENTRAL ILLINOIS WHERE ITS POSSIBLE THAT THIS PRECIP WILL START OFF AS MIX OF SNOW OR FREEZING DRIZZLE. AREAS TO THE SOUTH AND SOUTHEAST...ACROSS NORTHEAST ILLINOIS AND NORTHWEST INDIANA...COULD OBSERVE THIS MIX INITIALLY BUT WITH A HIGHER LIKELIHOOD FOR THIS PRECIP TO BE IN THE FORM OF ALL SNOW. THEN AREAS IN EAST CENTRAL ILLINOIS AND NORTHWEST INDIANA WILL OBSERVE ALL SNOW DURING THIS PERIOD. THIS VARYING PRECIP TYPE FROM FREEZING DRIZZLE WILL LIKELY CONTINUE INTO THURSDAY EVENING...WITH BETTER CHANCES FOR FREEZING DRIZZLE GOING INTO THE OVERNIGHT HOURS. HAVE A HALF INCH TO AN INCH OF WET SNOW FORECAST FOR THURSDAY AFTERNOON INTO THE EVENING FOR AREAS SOUTH AND SOUTHEAST OF I-88...WITH HIGHER SNOW AMOUNTS THE FURTHER SOUTHEAST. HAVE NOT MADE MENTION OF ANY ICE ACCUMULATION IN THE GRIDS...BUT THIS IS SOMETHING ALSO NEEDED TO BE MONITORED. ALTHOUGH ANY FREEZING DRIZZLE IS EXPECTED TO BE LIGHT...MINOR ICE ACCUMULATION COULD BE OBSERVED AND ESPECIALLY IF THIS FREEZING DRIZZLE PERSISTS INTO THURSDAY NIGHT. ONGOING WAA WILL FURTHER STRENGTHEN INTO FRIDAY WITH SCATTERED LIGHT PRECIP EXPECTED TO SPREAD NORTH ACROSS THE AREA FRIDAY MORNING. FURTHER WARMING OF THIS COLUMN WILL YIELD LIQUID PRECIP...BUT WITH SURFACE TEMPS FORECAST TO BE IN THE UPPER 20S. THIS IS ANOTHER PERIOD TO KEEP AN EYE ON WITH A PERIOD OF FREEZING RAIN POSSIBLE...ESPECIALLY IF THE BETTER PRECIP AXIS PUSHES NORTH BEFORE TEMPS RISE ABOVE FREEZING BY MID DAY FRIDAY. HAVE INCREASED POPS SIGNIFICANTLY FRIDAY INTO FRIDAY NIGHT AS GUIDANCE IS IN GOOD AGREEMENT FOR AN EXTENDED PERIOD OF LIGHT TO MODERATE RAIN TO FALL. YET ANOTHER PERIOD OF REINFORCING LIFT OWING TO A HIGHLY AMPLIFIED MID/UPPER LEVEL TROUGH AND ATTENDANT SURFACE LOW. ALONG WITH THIS LIFT...THIS APPROACHING SYSTEM WILL ALLOW FOR A WARMER AND MOIST ENVIRONMENT TO MOVE NORTHWARD DURING THIS PERIOD. RESULTANT RAINFALL AMOUNTS FROM FRIDAY AFTERNOON THROUGH EARLY SATURDAY MORNING WILL BE AROUND 1 INCH AND POSSIBLY HIGHER IN SOME LOCATIONS. THIS RAINFALL COINCIDING WITH THE CURRENT SNOWPACK COULD RAISE SOME ISSUES WITH REGARDS TO AREA RIVERS AND CREEKS...WITH RISES EXPECTED. ALSO...THIS RAIN AND SLIGHT WARMING WILL CREATE A SETUP FOR ICE JAM FLOODING TO BECOME MORE OF AN ISSUE. WILL CONTINUE TO MENTION THIS ASPECT IN THE HWO...WITH AN ESF LIKELY ISSUED OVERNIGHT TONIGHT OR TOMORROW. RODRIGUEZ && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 06Z... * PRECIP OVERSPREADING THE TERMINALS THURSDAY AFTERNOON... INITIALLY LIGHT SNOW...THEN SWITCHING OVER TO FREEZING DRIZZLE BY EARLY EVENING. * CIGS/VIS LOWERING TO MVFR BY THURSDAY AFTERNOON...AND AND CIGS LOWERING IFR THURSDAY EVENING. KREIN //DISCUSSION...UPDATED 06Z... AS HIGH PRESSURE BUILDS ACROSS THE REGION...CONDITIONS WILL REMAIN VFR WITH CALM TO LGT/VRBL WINDS INTO LATE THURSDAY MORNING. BY THEN...THE HGI WILL SHIFT OFF TO THE EAST AND WINDS WILL BECOME SELY-SSELY AND INCREASE...BUT REMAIN UNDER 10KT. A MID LEVEL DISTURBANCE LIFTING FROM THE SOUTHWEST WILL BRING LOWERING CIGS AND SOME LIGHT PCPN. WITH TEMPERATURES EXPECTED TO REMAIN BELOW FREEZING THROUGH THE DAY...AND WITH A SATURATED LAYER EXPECTED TO EXTEND TO 15KFT...INITIAL PCPN SHOULD BE LIGHT SNOW...THOUGH IF THE MOIST LAYER IS NOT QUITE THAT DEEP...PCPN COULD START OUT AS SOME LIGHT FREEZING DRIZZLE. HOWEVER...THE MOISTURE PROFILE GUIDANCE INDICATES THAT THE TOP OF THE MOIST LAYER WILL LOWER WITH TIME THROUGH THE AFTERNOON...AND BY EVENING THE MOIST LAYER WILL NO LONGER BE DEEP ENOUGH TO SUPPORT ICE PRODUCTION AND ANY LINGERING PCPN SHOULD CHANGE OVER TO LIGHT FREEZING DRIZZLE. WITH THE ONSET OF THE PCPN...VIS SHOULD LOWER TO MVFR LEVELS...BUT CIGS SHOULD GRADUALLY LOWER THROUGH MVFR TO IFR LEVELS INTO THE EVENING...WITH IFR CONDITIONS LIKELY PERSISTING THROUGH THE NIGHT. KREIN //ORD AND MDW CONFIDENCE...UPDATED 06Z... * MEDIUM CONFIDENCE IN TIMING OF ONSET OF PCPN. * MEDIUM CONFIDENCE IN PCPN STARTING AS -SN AND THEN CHANGING OVER TO -FZDZ BY EARLY EVENING...WITH LOW CONFIDENCE IN THE TIMING OF THE CHANGE OVER. * HIGH CONFIDENCE WIND TRENDS. * HIGH CONFIDENCE ON CIG TRENDS THURSDAY AFTERNOON AND EVENING... BUT LOWER CONFIDENCE IN THE EXACT TIMING OF THE CATAGORY CHANGES. KREIN //OUTLOOK FOR ORD/MDW FOR 12Z FRIDAY-12Z WEDNESDAY...UPDATED 00Z... FRIDAY...WINTRY MIX EARLY...BECOMING ALL RAIN. MVFR/IFR LIKELY. SATURDAY...CHANCE OF RAIN OR SNOW WITH IFR/MVFR DURING THE DAY. SUNDAY...SLIGHT CHANCE OF RAIN OR SNOW LATE. MVFR POSSIBLE. MONDAY...MVFR POSSIBLE. TUESDAY...SLIGHT CHANCE OF SNOW. MVFR POSSIBLE. KJB && .MARINE... 214 PM CST A FAIRLY QUIET PATTERN...AT LEAST OVER THE PAST FEW WEEKS...WILL PREVAIL OVER THE LAKE THROUGH THURSDAY MORNING AS HIGH PRESSURE REMAINS ANCHORED ACROSS THE SOUTHERN GREAT LAKES. AS THIS SCOOTS EAST LATER THURSDAY SOUTHERLY FLOW WILL RETURN ACROSS THE LAKE. THIS WILL STRENGTHEN ON FRIDAY INTO FRIDAY NIGHT AS LOW PRESSURE DEVELOPS IN THE CENTRAL PLAINS. THIS RETURN FLOW LOOKS TO SET UP AN INVERSION BY FRIDAY AFTERNOON AND NIGHT WHICH WILL LIMIT GUST MAGNITUDE BUT THERE STILL SHOULD BE REALIZED A FAIRLY STOUT SUSTAINED WIND OF AROUND 25 KT BY FRIDAY AFTERNOON INTO NIGHT. MODELS ARE IN GOOD AGREEMENT ON HAVING THE LOW PASS DIRECTLY ACROSS THE CENTRAL LAKES AS IT PROGRESSES NORTHEAST. THIS WILL SWING A COLD FRONT THROUGH LAKE MICHIGAN AS IT DOES SO TURNING WINDS WESTERLY. THE PATTERN NEXT WEEK LOOKS FAIRLY PROGRESSIVE WHICH COULD MEAN ACTIVE FOR THE GREAT LAKES REGION. THE AMOUNT OF ICE REMAINS HIGH ACROSS NEARSHORE AREAS AS SEEN IN WEBCAMS AND SATELLITE IMAGERY FROM YESTERDAY. MTF && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...NONE. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
755 PM CST FRI JAN 10 2014 .UPDATE... ISSUED AT 749 PM CST FRI JAN 10 2014 QUITE A FEW SITES NOW 1/2 TO 1/4 MILE ON VISIBILITIES AND SHOULD CONTINUE TO SEE VERY LOW VISIBILITIES BECOME WIDESPREAD WITH ABUNDANT MOISTURE AND DIMINISHING WINDS AHEAD OF PASSING SURFACE LOW. AS RESULT... HAVE ISSUED A DENSE FOG ADVISORY FOR THE ENTIRE CWA FOR THE REST OF TONIGHT. LATE TONIGHT... SAY AROUND 09Z OR SO WE MAY START TO SEE SOME IMPROVEMENT ON VISIBILITIES AS A FRONTAL BOUNDARY MOVES THROUGH THE REGION. THE POOR VISIBILITIES IN DENSE FOG COUPLED WITH ICY ROADWAYS ESPECIALLY NEAR/NORTH OF I-80 MAKING IT ONE OF THOSE NIGHTS BEST SUITED FOR NOT TRAVELING UNLESS NECESSARY. UPDATE ISSUED AT 444 PM CST FRI JAN 10 2014 EXPANDED ADVISORY TO INCLUDE JACKSON COUNTY IN IOWA AND JO DAVIESS AND STEPHENSON COUNTIES IN FAR NORTHERN ILLINOIS. REPORTS OF SEVERAL ROADS COMPLETELY COVERED IN JACKSON COUNTY... IA38...IA136 IA64. PAVEMENT TEMPS HOVERING AROUND FREEZING IN THESE AREAS ALLOWING FOR THE ICY CONDITIONS TO DEVELOP. COULD ACTUALLY SEE SOME IMPROVEMENT FOR A TIME THIS EVENING AS TEMPS CONTINUE TO SLOWLY CLIMB AHEAD OF AN APPROACHING SURFACE LOW. HOWEVER....ONCE THIS PASSES AND WINDS SHIFT TO WEST WILL SEE TEMPS DROP LATE THIS EVE AND OVERNIGHT AND MAY SEE MORE ICING WHETHER THROUGH REFREEZE OR POSSIBLY SOME LIGHT FREEZING DRIZZLE/FREEZING RAIN. UPDATE ISSUED AT 336 PM CST FRI JAN 10 2014 CALLS ARE NOW COMING IN REPORTING SLICK ROADS. THUS WILL HOIST A FREEZING RAIN ADVISORY FOR LATE AFTERNOON AND EVENING. TEMPORAL AND AREAL COVERAGE OF THE ADVISORY MAY NEED TO CHANGED THIS EVENING. && .SYNOPSIS... ISSUED AT 248 PM CST FRI JAN 10 2014 12Z UA ANALYSIS HAS A LLJ RUNNING FROM TEXAS INTO WESTERN MISSOURI. MOISTURE ASSOCIATED WITH THIS JET WAS IMPINGING UPON AN 850 MB WARM FRONT RUNNING FROM KANSAS INTO SOUTHERN ILLINOIS. RADAR TRENDS THROUGH MID AFTERNOON HAD A LARGE AREA OF RAIN FROM MISSOURI INTO ILLINOIS WITH LIGHTER RAIN/DRIZZLE MIXED WITH SOME FREEZING RAIN/DRIZZLE ACROSS IOWA. 18Z SFC ANALYSIS HAS A WEAK LOW NEAR KMHK WITH A WARM FRONT EAST ALONG THE MISSOURI RIVER. THE COLD FRONT RAN FROM THE LOW INTO SOUTHWEST OKLAHOMA. DEW POINTS WERE IN THE 20S AND 30S ACROSS THE UPPER MIDWEST AND GREAT LAKES WITH 40S AND HIGHER FROM THE OHIO VALLEY AND SOUTHERN PLAINS. && .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 248 PM CST FRI JAN 10 2014 BASED ON TRENDS FROM PRESSURE FALLS AND THE RAP MODEL...THE LOW SHOULD PASS OVER THE FAR NORTHWEST AREA BETWEEN KALO AND KCID THIS EVENING. WINDS WILL DECREASE AS THE LOW APPROACHES AND THE FOG IS EXPECTED TO BECOME MORE WIDESPREAD. RIGHT NOW NO ADVISORY FOR DENSE FOG IS PLANNED. HOWEVER...I WOULD NOT BE SURPRISED IF ONE IS NEEDED AT SOME POINT DURING THE EVENING. TEMPERATURES HAVE NOT BUDGED MUCH IN THE HIGHWAY 20 CORRIDOR FROM KDBQ ON WEST. THUS THIS AREA IS RIGHT ON THE CUSP OF SEEING FREEZING RAIN LATE THIS AFTERNOON AND EVENING AS LIFT CONTINUES TO INCREASE. HOWEVER...THE TRACK OF THE LOW SHOULD ALLOW TEMPERATURES TO RISE ABOUT ANOTHER DEGREE. FREEZING RAIN IS EXPECTED TO BE LOCALLY SPOTTY OVER THE FOUR NORTHWEST COUNTIES AND POSSIBLY WESTERN DUBUQUE COUNTY THROUGH MID EVENING. ONCE THE LOW PASSES...COLD AIR WILL SLOWLY BEGIN TO MOVE INTO THE AREA ALLOWING THE RAIN TO MIX WITH AND CHANGE TO SNOW FROM WEST TO EAST OVERNIGHT. DURING THE CHANGE OVER...A BRIEF PERIOD OF FREEZING RAIN WILL BE POSSIBLE. SNOW AMOUNTS WILL RANGE FROM A TRACE TO UNDER AN INCH. ON SATURDAY...LINGERING LIGHT SNOW WILL BE SEE OVER ROUGHLY THE NORTHEAST/EAST HALF OF THE AREA DURING THE MORNING. OTHERWISE DRY CONDITIONS ARE EXPECTED DURING THE DAY. SNOW AMOUNTS SATURDAY MORNING WILL BE A DUSTING AT BEST. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 248 PM CST FRI JAN 10 2014 NEARLY ZONAL UPPER AIR FLOW WILL BE OVER THE AREA THE REST OF THE WEEKEND THEN THE PATTERN CHANGES TO A RIDGE DOMINATED WESTERN U.S. AND A MEAN TROF SETTING UP OVER THE EAST. MILD CONDITIONS ARE ANTICIPATED FOR THE REGION SUNDAY AS UPPER RIDGING BUILDS OVER THE AREA SATURDAY NIGHT INTO SUNDAY. IN THE LOW LEVELS A SURFACE RIDGE WILL MOVE THROUGH THE REGION SATURDAY EVENING FOLLOWED BY STRONG LOW LEVEL WAA AHEAD OF A TROF DIGGING INTO THE SOUTHWEST U.S. AND A COLD FRONT OVER THE PLAINS. A LOW LEVEL THERMAL RIDGE CROSSES THE MID MISSISSIPPI VALLEY SUNDAY WITH H8 TEMPS PEAKING IN THE +8 TO +10C RANGE DURING THE AFTERNOON. GOOD MIXING IS ALSO SUGGESTED WITH A TIGHT SLP GRADIENT AHEAD OF THE COLD FRONT. EVEN WITH THE SNOW COVER...WE SHOULD SEE HIGHS TOPPING OUT IN THE MID 30S TO MID 40S. MODELS MOVE THE FRONT THROUGH THE REGION WITH OUT ANY PRECIPITATION SUNDAY NIGHT. THIS LOOKS REASONABLE WITH THE BETTER MOISTURE GETTING PUSHED OUT WELL AHEAD OF THE SYSTEM. THERE IS SOME CONCERN MONDAY WITH THE LESS PHASED ECM SOLUTION LIFTING A PIECE OF THE UPPER TROF OUT OF TEXAS...SENDING A SURFACE LOW NORTHEAST THROUGH THE OHIO VALLEY. THE ECMS PRECIP SHIELD WITH THIS FEATURE JUST MISSES THE SOUTHEAST CWFA MONDAY. MODELS DO AGREE ON A WEAK S/W RACING SOUTHEAST THROUGH THE DAKOTAS AND MN MONDAY AND MONDAY NIGHT WITH THE LATEST RUNS MOVING IT/S WEAK SURFACE LOW THROUGH IA AND FAVOR THE NORTHEAST CWFA FOR SOME LOW POPS FOR LIGHT SNOW. JUST A QUICK SHOT OF COLD AIR IS EXPECTED BEHIND THIS FEATURE WITH THE COLDEST TEMPS EXPECTED WEDNESDAY MORNING WITH LOWS IN THE SINGLE DIGITS AND TEENS. FOR THE END OF THE WEEK ANOTHER S/W MOVING OUT OF THE CANADIAN ROCKIES WILL SEND A SURFACE LOW EAST ALONG THE U.S. CANADIAN BORDER...DRAGGING A COLD FRONT THROUGH THE REGION WEDNESDAY NIGHT OR THURSDAY MORNING. THE FRONT SHOULD MOVE THROUGH DRY WITH A LARGE AREA OF HIGH PRESSURE OVER THE WESTERN GULF BLOCKING ANY MOISTURE RETURN. BUT THE NORTHEAST COULD SEE SOME LIGHT SNOW IN THE CYCLONIC FLOW AROUND THE SURFACE LOW AS IT MOVES INTO EASTERN CANADA THURSDAY NIGHT AND FRIDAY. MODELS SHOW THE SYSTEM DRAGGING DOWN ANOTHER CHUNK OF ARCTIC AIR WITH BOTH THE ECM AND GFS BRINGING H8 TEMPS AS COLD AS -22C OVER THE AREA THURSDAY NIGHT. THIS COULD RESULT IN SUBZERO TEMPERATURES OVER THE NORTH BY SATURDAY MORNING. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING) ISSUED AT 540 PM CST FRI JAN 10 2014 GENERALLY LIFR/VLIFR CONDITIONS EXPECTED TONIGHT WITH LIKELY AREAS OF BELOW MINIMUMS DEVELOPING IN DENSE FOG. LOW PRESSURE WILL MOVE THROUGH NORTHEAST IOWA AND INTO WISCONSIN. THIS WILL SEND A FRONT THROUGH THE TERMINALS OVERNIGHT WITH RISK OF MIXED PRECIPITATION WITH COLDER AIR ARRIVING ON WEST TO NORTHWEST WINDS. EXPECT GRADUAL IMPROVEMENT TO MVFR ON SATURDAY WITH POSSIBLY SOME VFR IN THE AFTERNOON. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...DENSE FOG ADVISORY UNTIL 6 AM CST SATURDAY FOR BENTON-BUCHANAN- CEDAR-CLINTON-DELAWARE-DES MOINES-DUBUQUE-HENRY IA-IOWA- JACKSON-JEFFERSON-JOHNSON-JONES-KEOKUK-LEE-LINN-LOUISA- MUSCATINE-SCOTT-VAN BUREN-WASHINGTON. FREEZING RAIN ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR BENTON- BUCHANAN-CLINTON-DELAWARE-DUBUQUE-JACKSON-JONES-LINN. IL...DENSE FOG ADVISORY UNTIL 6 AM CST SATURDAY FOR BUREAU-CARROLL- HANCOCK-HENDERSON-HENRY IL-JO DAVIESS-MCDONOUGH-MERCER- PUTNAM-ROCK ISLAND-STEPHENSON-WARREN-WHITESIDE. FREEZING RAIN ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR CARROLL-JO DAVIESS-STEPHENSON-WHITESIDE. MO...DENSE FOG ADVISORY UNTIL 6 AM CST SATURDAY FOR CLARK-SCOTLAND. && $$ UPDATE...05 SYNOPSIS...08 SHORT TERM...08 LONG TERM...DLF AVIATION...05
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
549 PM CST FRI JAN 10 2014 .UPDATE... ISSUED AT 444 PM CST FRI JAN 10 2014 EXPANDED ADVISORY TO INCLUDE JACKSON COUNTY IN IOWA AND JO DAVIESS AND STEPHENSON COUNTIES IN FAR NORTHERN ILLINOIS. REPORTS OF SEVERAL ROADS COMPLETELY COVERED IN JACKSON COUNTY... IA38...IA136 IA64. PAVEMENT TEMPS HOVERING AROUND FREEZING IN THESE AREAS ALLOWING FOR THE ICY CONDITIONS TO DEVELOP. COULD ACTUALLY SEE SOME IMPROVEMENT FOR A TIME THIS EVENING AS TEMPS CONTINUE TO SLOWLY CLIMB AHEAD OF AN APPROACHING SURFACE LOW. HOWEVER....ONCE THIS PASSES AND WINDS SHIFT TO WEST WILL SEE TEMPS DROP LATE THIS EVE AND OVERNIGHT AND MAY SEE MORE ICING WHETHER THROUGH REFREEZE OR POSSIBLY SOME LIGHT FREEZING DRIZZLE/FREEZING RAIN. UPDATE ISSUED AT 336 PM CST FRI JAN 10 2014 CALLS ARE NOW COMING IN REPORTING SLICK ROADS. THUS WILL HOIST A FREEZING RAIN ADVISORY FOR LATE AFTERNOON AND EVENING. TEMPORAL AND AREAL COVERAGE OF THE ADVISORY MAY NEED TO CHANGED THIS EVENING. && .SYNOPSIS... ISSUED AT 248 PM CST FRI JAN 10 2014 12Z UA ANALYSIS HAS A LLJ RUNNING FROM TEXAS INTO WESTERN MISSOURI. MOISTURE ASSOCIATED WITH THIS JET WAS IMPINGING UPON AN 850 MB WARM FRONT RUNNING FROM KANSAS INTO SOUTHERN ILLINOIS. RADAR TRENDS THROUGH MID AFTERNOON HAD A LARGE AREA OF RAIN FROM MISSOURI INTO ILLINOIS WITH LIGHTER RAIN/DRIZZLE MIXED WITH SOME FREEZING RAIN/DRIZZLE ACROSS IOWA. 18Z SFC ANALYSIS HAS A WEAK LOW NEAR KMHK WITH A WARM FRONT EAST ALONG THE MISSOURI RIVER. THE COLD FRONT RAN FROM THE LOW INTO SOUTHWEST OKLAHOMA. DEW POINTS WERE IN THE 20S AND 30S ACROSS THE UPPER MIDWEST AND GREAT LAKES WITH 40S AND HIGHER FROM THE OHIO VALLEY AND SOUTHERN PLAINS. && .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 248 PM CST FRI JAN 10 2014 BASED ON TRENDS FROM PRESSURE FALLS AND THE RAP MODEL...THE LOW SHOULD PASS OVER THE FAR NORTHWEST AREA BETWEEN KALO AND KCID THIS EVENING. WINDS WILL DECREASE AS THE LOW APPROACHES AND THE FOG IS EXPECTED TO BECOME MORE WIDESPREAD. RIGHT NOW NO ADVISORY FOR DENSE FOG IS PLANNED. HOWEVER...I WOULD NOT BE SURPRISED IF ONE IS NEEDED AT SOME POINT DURING THE EVENING. TEMPERATURES HAVE NOT BUDGED MUCH IN THE HIGHWAY 20 CORRIDOR FROM KDBQ ON WEST. THUS THIS AREA IS RIGHT ON THE CUSP OF SEEING FREEZING RAIN LATE THIS AFTERNOON AND EVENING AS LIFT CONTINUES TO INCREASE. HOWEVER...THE TRACK OF THE LOW SHOULD ALLOW TEMPERATURES TO RISE ABOUT ANOTHER DEGREE. FREEZING RAIN IS EXPECTED TO BE LOCALLY SPOTTY OVER THE FOUR NORTHWEST COUNTIES AND POSSIBLY WESTERN DUBUQUE COUNTY THROUGH MID EVENING. ONCE THE LOW PASSES...COLD AIR WILL SLOWLY BEGIN TO MOVE INTO THE AREA ALLOWING THE RAIN TO MIX WITH AND CHANGE TO SNOW FROM WEST TO EAST OVERNIGHT. DURING THE CHANGE OVER...A BRIEF PERIOD OF FREEZING RAIN WILL BE POSSIBLE. SNOW AMOUNTS WILL RANGE FROM A TRACE TO UNDER AN INCH. ON SATURDAY...LINGERING LIGHT SNOW WILL BE SEE OVER ROUGHLY THE NORTHEAST/EAST HALF OF THE AREA DURING THE MORNING. OTHERWISE DRY CONDITIONS ARE EXPECTED DURING THE DAY. SNOW AMOUNTS SATURDAY MORNING WILL BE A DUSTING AT BEST. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 248 PM CST FRI JAN 10 2014 NEARLY ZONAL UPPER AIR FLOW WILL BE OVER THE AREA THE REST OF THE WEEKEND THEN THE PATTERN CHANGES TO A RIDGE DOMINATED WESTERN U.S. AND A MEAN TROF SETTING UP OVER THE EAST. MILD CONDITIONS ARE ANTICIPATED FOR THE REGION SUNDAY AS UPPER RIDGING BUILDS OVER THE AREA SATURDAY NIGHT INTO SUNDAY. IN THE LOW LEVELS A SURFACE RIDGE WILL MOVE THROUGH THE REGION SATURDAY EVENING FOLLOWED BY STRONG LOW LEVEL WAA AHEAD OF A TROF DIGGING INTO THE SOUTHWEST U.S. AND A COLD FRONT OVER THE PLAINS. A LOW LEVEL THERMAL RIDGE CROSSES THE MID MISSISSIPPI VALLEY SUNDAY WITH H8 TEMPS PEAKING IN THE +8 TO +10C RANGE DURING THE AFTERNOON. GOOD MIXING IS ALSO SUGGESTED WITH A TIGHT SLP GRADIENT AHEAD OF THE COLD FRONT. EVEN WITH THE SNOW COVER...WE SHOULD SEE HIGHS TOPPING OUT IN THE MID 30S TO MID 40S. MODELS MOVE THE FRONT THROUGH THE REGION WITH OUT ANY PRECIPITATION SUNDAY NIGHT. THIS LOOKS REASONABLE WITH THE BETTER MOISTURE GETTING PUSHED OUT WELL AHEAD OF THE SYSTEM. THERE IS SOME CONCERN MONDAY WITH THE LESS PHASED ECM SOLUTION LIFTING A PIECE OF THE UPPER TROF OUT OF TEXAS...SENDING A SURFACE LOW NORTHEAST THROUGH THE OHIO VALLEY. THE ECMS PRECIP SHIELD WITH THIS FEATURE JUST MISSES THE SOUTHEAST CWFA MONDAY. MODELS DO AGREE ON A WEAK S/W RACING SOUTHEAST THROUGH THE DAKOTAS AND MN MONDAY AND MONDAY NIGHT WITH THE LATEST RUNS MOVING IT/S WEAK SURFACE LOW THROUGH IA AND FAVOR THE NORTHEAST CWFA FOR SOME LOW POPS FOR LIGHT SNOW. JUST A QUICK SHOT OF COLD AIR IS EXPECTED BEHIND THIS FEATURE WITH THE COLDEST TEMPS EXPECTED WEDNESDAY MORNING WITH LOWS IN THE SINGLE DIGITS AND TEENS. FOR THE END OF THE WEEK ANOTHER S/W MOVING OUT OF THE CANADIAN ROCKIES WILL SEND A SURFACE LOW EAST ALONG THE U.S. CANADIAN BORDER...DRAGGING A COLD FRONT THROUGH THE REGION WEDNESDAY NIGHT OR THURSDAY MORNING. THE FRONT SHOULD MOVE THROUGH DRY WITH A LARGE AREA OF HIGH PRESSURE OVER THE WESTERN GULF BLOCKING ANY MOISTURE RETURN. BUT THE NORTHEAST COULD SEE SOME LIGHT SNOW IN THE CYCLONIC FLOW AROUND THE SURFACE LOW AS IT MOVES INTO EASTERN CANADA THURSDAY NIGHT AND FRIDAY. MODELS SHOW THE SYSTEM DRAGGING DOWN ANOTHER CHUNK OF ARCTIC AIR WITH BOTH THE ECM AND GFS BRINGING H8 TEMPS AS COLD AS -22C OVER THE AREA THURSDAY NIGHT. THIS COULD RESULT IN SUBZERO TEMPERATURES OVER THE NORTH BY SATURDAY MORNING. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING) ISSUED AT 540 PM CST FRI JAN 10 2014 GENERALLY LIFR/VLIFR CONDITIONS EXPECTED TONIGHT WITH LIKELY AREAS OF BELOW MINIMUMS DEVELOPING IN DENSE FOG. LOW PRESSURE WILL MOVE THROUGH NORTHEAST IOWA AND INTO WISCONSIN. THIS WILL SEND A FRONT THROUGH THE TERMINALS OVERNIGHT WITH RISK OF MIXED PRECIPITATION WITH COLDER AIR ARRIVING ON WEST TO NORTHWEST WINDS. EXPECT GRADUAL IMPROVEMENT TO MVFR ON SATURDAY WITH POSSIBLY SOME VFR IN THE AFTERNOON. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...FREEZING RAIN ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR BENTON- BUCHANAN-DELAWARE-DUBUQUE-JACKSON-JONES-LINN. IL...FREEZING RAIN ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR JO DAVIESS- STEPHENSON. MO...NONE. && $$ UPDATE...05 SYNOPSIS...08 SHORT TERM...08 LONG TERM...DLF AVIATION...05
AREA FORECAST DISCUSSION
NWS GOODLAND KS
400 PM MST THU JAN 9 2014 .SHORT TERM...(THIS AFTERNOON THROUGH FRIDAY) ISSUED AT 106 PM MST THU JAN 9 2014 LATEST WV IMAGERY AND RAP H5 ANALYSIS SHOW A PROGRESSIVE ZONAL PATTERN IN PLACE ACROSS THE CONUS WITH A SPLIT TROUGH OVER THE WESTERN US. PV HEIGHT MINIMUM IS OVER SOUTHERN IDAHO WITH ENHANCEMENT AHEAD OF THIS FEATURE ON WV IMAGERY ACROSS WYOMING. THIS AFTERNOON...FOG HAS LIFTED OVER THE CWA...HOWEVER THERE CONTINUES TO BE SEVERAL AREAS OF LOW STRATUS LINGERING ACROSS THE REGION...WITH THE MOST EXTENSIVE AREA OVER CENTRAL KANSAS. WHILE SURFACE TROUGH HAS SHIFTED EAST AND ALL INDICATIONS BY SHORT RANGE GUIDANCE TEMPS HAVE MODIFIED ALOFT...WITH COLD POOL SHIFTING EAST. THERE HAS BEEN LESS OF A REFLECTION OF THE CHANGE IN AIR MASS WITH TEMPS SLOW TO RECOVER SO FAR. WILL LIKELY NEED TO KEEP AN EYE ON TRENDS...BUT I BUMPED EXPECTED HIGHS DOWN A LITTLE TO MATCH THE SLOWER RATE OF WARMING THIS AFTERNOON. TONIGHT-FRIDAY...AS UPPER TROUGH SHIFTS EAST TONIGHT BEST FORCING/MOISTURE WILL REMAIN WELL EAST OF THE CWA. BL MOISTURE WILL REMAIN HIGH HOWEVER OVER EASTERN LOCATIONS WHERE FOG/STRATUS HAVE BEEN SLOWER TO ERODE AND FURTHER FOG/STRATUS DEVELOPMENT IS LIKELY. AS THE UPPER LEVEL SYSTEM SHIFTS EAST ANY FOG THAT DOES DEVELOP SHOULD QUICKLY PUSH EAST AS GUSTY NW WINDS DRY OUT THE BL. WHILE FORCING WILL BE INCREASING AS NOSE OF H3 JET ON THE BACK SIDE OF THE UPPER LOW MOVES ACROSS OUR CWA LATE TONIGHT THROUGH FRIDAY...MOISTURE PROFILES CONTINUE TO BE UNIMPRESSIVE THROUGH MOST OF THESE PERIODS. 15-18Z MODEL SOUNDINGS ARE MORE IMPRESSIVE AND WOULD SUPPORT PRECIPITATION. I KEPT POP MENTION TO SLIGHT CHANCE STARTING AFTER 06Z TONIGHT IN THE NW AND OVERSPREADING MOST OF THE CWA THROUGH FRIDAY. ANY PRECIP SHOULD START OUT AS LIGHT SNOW MIXING WITH AND CHANGING TO RAIN DURING THE DAYTIME PERIOD. DUE TO THE QUICK NATURE OF THE SYSTEM AND GENERAL LACK OF MOISTURE AMOUNTS SHOULD BE VERY LIGHT. .LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY) ISSUED AT 220 PM MST THU JAN 9 2014 FRIDAY NIGHT A STRONG 300MB JET STREAK WILL MOVE IN BEHIND THE EXITING TROUGH AXIS. AS THE JET STREAK MOVES IN THE LEFT EXIT OF THE JET STREAK WILL MOVE OVER THE AREA. WITH SATURATED MID LEVELS REMAINING BEHIND THE TROUGH AXIS AND A 500MB SHORT WAVE TROUGH ALSO MOVING OVER THE AREA...CANNOT COMPLETELY RULE OUT SOME LINGERING LIGHT SNOW DURING THE NIGHT. BEHIND THE 500MB SHORT WAVE TROUGH THE ENVIRONMENT WILL DRY OUT AND SUBSIDENCE WILL MOVE IN. SATURDAY AN UPPER LEVEL RIDGE WILL MOVE THROUGH DURING THE DAY AND THE ENVIRONMENT WILL CONTINUE TO DRY OUT. BEHIND THE RIDGE AXIS WARMER AIR WILL ADVECT OVER THE AREA ALLOWING TEMPERATURES TO WARM. SATURDAY NIGHT A SURFACE TROUGH WILL MOVE THROUGH THE AREA. DUE TO THE DRY ENVIRONMENT IN PLACE AM NOT ANTICIPATING ANYTHING MORE THAN HIGH CLOUDS TO ACCOMPANY THE TROUGH PASSAGE. FOR SUNDAY THROUGH THURSDAY WARMER AND WINDY WILL BE THE PRIMARY WEATHER THEME. AN UPPER LEVEL SHORT WAVE TROUGH WILL MOVE OVER THE AREA SUNDAY WHICH MAY BRING SOME MINIMAL CHANCES FOR RAINFALL TO PARTS OF THE AREA. HOWEVER MODELS ARE SUGGESTING A SPLIT UPPER LEVEL JET WHICH USUALLY IS NOT FAVORABLE FOR DEVELOPING PRECIP. OVER THE TRI-STATE AREA. BEHIND THE TROUGH THE UPPER LEVEL FLOW WILL REMAIN FROM THE NORTHWEST THROUGH THE PERIOD AS AN UPPER LEVEL RIDGE BUILDS OVER THE WESTERN CONUS. A COLD FRONT WILL MOVE THROUGH TUESDAY AND THURSDAY ALONG WITH AN UPPER LEVEL SHORT WAVE TROUGH. HOWEVER THE MAJORITY OF THE JET DYNAMICS WITH THE SHORT WAVE TROUGH WILL BE OVER THE GREAT LAKES. AS SUCH BELIEVE THE AREA WILL BE DRY WITH BOTH FRONTAL PASSAGES. WITH A STRONG NORTHWEST FLOW PATTERN OVER THE AREA THIS PERIOD WILL BE WINDY. HIGH TEMPERATURES FOR THE PERIOD WILL BE ABOVE NORMAL EXCEPT FOR TUESDAY AND THURSDAY WHEN A COLD FRONT MOVES THROUGH. LOW TEMPERATURES FOR THE PERIOD WILL BE NEAR NORMAL. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING) ISSUED AT 400 PM MST THU JAN 9 2014 UPPER TROUGH AND ASSOCIATED COLD FRONT MOVE THROUGH KGLD AND KMCK TERMINALS IN THE 08Z-10Z TIMEFRAME SHIFTING WINDS FROM SOUTH/SOUTHWESTERLY AROUND 10KTS TO THE NORTHWEST AT 15-20KTS WITH HIGHER GUSTS. THESE GUSTY WINDS WILL CONTINUE THROUGH 23Z FRIDAY BEFORE DECREASING TO 10KTS OR SO FROM THE WEST/NORTHWEST. THERE WILL BE A SLIGHT CHANCE FOR LIGHT SNOW AT BOTH TERMINALS IN THE 11-15Z TIME FRAME ALTHOUGH RIGHT NOW KGLD LOOKS TO HAVE A SLIGHTLY BETTER CHANCE AND HAVE INCLUDED A PROB30 GROUP FOR IT. OTHERWISE...ONLY AVIATION CONCERN IS FOR THE POSSIBILITY OF SOME BR/FG AND MVFR CIGS AT KMCK AS STRATUS DECK CURRENTLY JUST EAST OF THE TERMINAL COULD SPREAD WESTWARD AHEAD OF THE WIND SHIFT IN THE 06Z-13Z TIMEFRAME. OTHERWISE ANOTHER WEAK DISTURBANCE MOVES DOWN IN THE 16Z-19Z TIMEFRAME AND COULD ALSO PRODUCE SOME MVFR CIGS. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...DR LONG TERM...JTL AVIATION...99
AREA FORECAST DISCUSSION
NWS GOODLAND KS
222 PM MST THU JAN 9 2014 .SHORT TERM...(THIS AFTERNOON THROUGH FRIDAY) ISSUED AT 106 PM MST THU JAN 9 2014 LATEST WV IMAGERY AND RAP H5 ANALYSIS SHOW A PROGRESSIVE ZONAL PATTERN IN PLACE ACROSS THE CONUS WITH A SPLIT TROUGH OVER THE WESTERN US. PV HEIGHT MINIMUM IS OVER SOUTHERN IDAHO WITH ENHANCEMENT AHEAD OF THIS FEATURE ON WV IMAGERY ACROSS WYOMING. THIS AFTERNOON...FOG HAS LIFTED OVER THE CWA...HOWEVER THERE CONTINUES TO BE SEVERAL AREAS OF LOW STRATUS LINGERING ACROSS THE REGION...WITH THE MOST EXTENSIVE AREA OVER CENTRAL KANSAS. WHILE SURFACE TROUGH HAS SHIFTED EAST AND ALL INDICATIONS BY SHORT RANGE GUIDANCE TEMPS HAVE MODIFIED ALOFT...WITH COLD POOL SHIFTING EAST. THERE HAS BEEN LESS OF A REFLECTION OF THE CHANGE IN AIR MASS WITH TEMPS SLOW TO RECOVER SO FAR. WILL LIKELY NEED TO KEEP AN EYE ON TRENDS...BUT I BUMPED EXPECTED HIGHS DOWN A LITTLE TO MATCH THE SLOWER RATE OF WARMING THIS AFTERNOON. TONIGHT-FRIDAY...AS UPPER TROUGH SHIFTS EAST TONIGHT BEST FORCING/MOISTURE WILL REMAIN WELL EAST OF THE CWA. BL MOISTURE WILL REMAIN HIGH HOWEVER OVER EASTERN LOCATIONS WHERE FOG/STRATUS HAVE BEEN SLOWER TO ERODE AND FURTHER FOG/STRATUS DEVELOPMENT IS LIKELY. AS THE UPPER LEVEL SYSTEM SHIFTS EAST ANY FOG THAT DOES DEVELOP SHOULD QUICKLY PUSH EAST AS GUSTY NW WINDS DRY OUT THE BL. WHILE FORCING WILL BE INCREASING AS NOSE OF H3 JET ON THE BACK SIDE OF THE UPPER LOW MOVES ACROSS OUR CWA LATE TONIGHT THROUGH FRIDAY...MOISTURE PROFILES CONTINUE TO BE UNIMPRESSIVE THROUGH MOST OF THESE PERIODS. 15-18Z MODEL SOUNDINGS ARE MORE IMPRESSIVE AND WOULD SUPPORT PRECIPITATION. I KEPT POP MENTION TO SLIGHT CHANCE STARTING AFTER 06Z TONIGHT IN THE NW AND OVERSPREADING MOST OF THE CWA THROUGH FRIDAY. ANY PRECIP SHOULD START OUT AS LIGHT SNOW MIXING WITH AND CHANGING TO RAIN DURING THE DAYTIME PERIOD. DUE TO THE QUICK NATURE OF THE SYSTEM AND GENERAL LACK OF MOISTURE AMOUNTS SHOULD BE VERY LIGHT. .LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY) ISSUED AT 220 PM MST THU JAN 9 2014 FRIDAY NIGHT A STRONG 300MB JET STREAK WILL MOVE IN BEHIND THE EXITING TROUGH AXIS. AS THE JET STREAK MOVES IN THE LEFT EXIT OF THE JET STREAK WILL MOVE OVER THE AREA. WITH SATURATED MID LEVELS REMAINING BEHIND THE TROUGH AXIS AND A 500MB SHORT WAVE TROUGH ALSO MOVING OVER THE AREA...CANNOT COMPLETELY RULE OUT SOME LINGERING LIGHT SNOW DURING THE NIGHT. BEHIND THE 500MB SHORT WAVE TROUGH THE ENVIRONMENT WILL DRY OUT AND SUBSIDENCE WILL MOVE IN. SATURDAY AN UPPER LEVEL RIDGE WILL MOVE THROUGH DURING THE DAY AND THE ENVIRONMENT WILL CONTINUE TO DRY OUT. BEHIND THE RIDGE AXIS WARMER AIR WILL ADVECT OVER THE AREA ALLOWING TEMPERATURES TO WARM. SATURDAY NIGHT A SURFACE TROUGH WILL MOVE THROUGH THE AREA. DUE TO THE DRY ENVIRONMENT IN PLACE AM NOT ANTICIPATING ANYTHING MORE THAN HIGH CLOUDS TO ACCOMPANY THE TROUGH PASSAGE. FOR SUNDAY THROUGH THURSDAY WARMER AND WINDY WILL BE THE PRIMARY WEATHER THEME. AN UPPER LEVEL SHORT WAVE TROUGH WILL MOVE OVER THE AREA SUNDAY WHICH MAY BRING SOME MINIMAL CHANCES FOR RAINFALL TO PARTS OF THE AREA. HOWEVER MODELS ARE SUGGESTING A SPLIT UPPER LEVEL JET WHICH USUALLY IS NOT FAVORABLE FOR DEVELOPING PRECIP. OVER THE TRI-STATE AREA. BEHIND THE TROUGH THE UPPER LEVEL FLOW WILL REMAIN FROM THE NORTHWEST THROUGH THE PERIOD AS AN UPPER LEVEL RIDGE BUILDS OVER THE WESTERN CONUS. A COLD FRONT WILL MOVE THROUGH TUESDAY AND THURSDAY ALONG WITH AN UPPER LEVEL SHORT WAVE TROUGH. HOWEVER THE MAJORITY OF THE JET DYNAMICS WITH THE SHORT WAVE TROUGH WILL BE OVER THE GREAT LAKES. AS SUCH BELIEVE THE AREA WILL BE DRY WITH BOTH FRONTAL PASSAGES. WITH A STRONG NORTHWEST FLOW PATTERN OVER THE AREA THIS PERIOD WILL BE WINDY. HIGH TEMPERATURES FOR THE PERIOD WILL BE ABOVE NORMAL EXCEPT FOR TUESDAY AND THURSDAY WHEN A COLD FRONT MOVES THROUGH. LOW TEMPERATURES FOR THE PERIOD WILL BE NEAR NORMAL. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 1036 AM MST THU JAN 9 2014 LIGHT FOG IS STILL BEING REPORTED AT SOME LOCATIONS ACROSS NORTHWEST KS AND SOUTHWEST NEBRASKA WITH MVFR VIS. AT THIS POINT VFR CONDITIONS SHOULD PREVAIL THROUGH THE REST OF THE AFTERNOON BASED ON LATEST SATELLITE/OBS TRENDS AT BOTH KGLD AND KMCK...THOUGH BRIEF DROPS TO NEAR 5-6SM AT KMCK COULD NOT BE RULED OUT NEAR THE VALID TAF TIME. WILL KEEP MENTION OUT FOR NOW SINCE CONFIDENCE IN VFR CONDITIONS IS HIGHER...AND THESE CONDITIONS WOULD BE VERY BRIEF. FOG MAY REDEVELOP LATE TONIGHT ACROSS CENTRAL KS AND ADVECT NORTH TO BE NEAR KMCK. AT THIS TIME VFR CONDITIONS SHOULD PREVAIL...THOUGH WE MAY SEE A BRIEF PERIOD OF 3-5SM VIS AT KMCK AFTER 06Z. JUST NOT A HIGH ENOUGH CHANCE AT THE TERMINAL TO INCLUDE IN THIS UPDATE. AS AN UPPER LEVEL SYSTEM MOVES INTO THE REGION WINDS SHOULD SHIFT FROM THE SOUTH TO THE WEST AFTER 06Z WITH GUSTS AROUND 25KT AT BOTH TERMINALS. WINDS WILL LIKELY REMAIN BELOW 12KT AT KMCK UNTIL CLOSER TO 12-14Z BASED ON CURRENT GUIDANCE. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...DR LONG TERM...JTL AVIATION...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
107 PM MST THU JAN 9 2014 .SHORT TERM...(THIS AFTERNOON THROUGH FRIDAY) ISSUED AT 106 PM MST THU JAN 9 2014 LATEST WV IMAGERY AND RAP H5 ANALYSIS SHOW A PROGRESSIVE ZONAL PATTERN IN PLACE ACROSS THE CONUS WITH A SPLIT TROUGH OVER THE WESTERN US. PV HEIGHT MINIMUM IS OVER SOUTHERN IDAHO WITH ENHANCEMENT AHEAD OF THIS FEATURE ON WV IMAGERY ACROSS WYOMING. THIS AFTERNOON...FOG HAS LIFTED OVER THE CWA...HOWEVER THERE CONTINUES TO BE SEVERAL AREAS OF LOW STRATUS LINGERING ACROSS THE REGION...WITH THE MOST EXTENSIVE AREA OVER CENTRAL KANSAS. WHILE SURFACE TROUGH HAS SHIFTED EAST AND ALL INDICATIONS BY SHORT RANGE GUIDANCE TEMPS HAVE MODIFIED ALOFT...WITH COLD POOL SHIFTING EAST. THERE HAS BEEN LESS OF A REFLECTION OF THE CHANGE IN AIR MASS WITH TEMPS SLOW TO RECOVER SO FAR. WILL LIKELY NEED TO KEEP AN EYE ON TRENDS...BUT I BUMPED EXPECTED HIGHS DOWN A LITTLE TO MATCH THE SLOWER RATE OF WARMING THIS AFTERNOON. TONIGHT-FRIDAY...AS UPPER TROUGH SHIFTS EAST TONIGHT BEST FORCING/MOISTURE WILL REMAIN WELL EAST OF THE CWA. BL MOISTURE WILL REMAIN HIGH HOWEVER OVER EASTERN LOCATIONS WHERE FOG/STRATUS HAVE BEEN SLOWER TO ERODE AND FURTHER FOG/STRATUS DEVELOPMENT IS LIKELY. AS THE UPPER LEVEL SYSTEM SHIFTS EAST ANY FOG THAT DOES DEVELOP SHOULD QUICKLY PUSH EAST AS GUSTY NW WINDS DRY OUT THE BL. WHILE FORCING WILL BE INCREASING AS NOSE OF H3 JET ON THE BACK SIDE OF THE UPPER LOW MOVES ACROSS OUR CWA LATE TONIGHT THROUGH FRIDAY...MOISTURE PROFILES CONTINUE TO BE UNIMPRESSIVE THROUGH MOST OF THESE PERIODS. 15-18Z MODEL SOUNDINGS ARE MORE IMPRESSIVE AND WOULD SUPPORT PRECIPITATION. I KEPT POP MENTION TO SLIGHT CHANCE STARTING AFTER 06Z TONIGHT IN THE NW AND OVERSPREADING MOST OF THE CWA THROUGH FRIDAY. ANY PRECIP SHOULD START OUT AS LIGHT SNOW MIXING WITH AND CHANGING TO RAIN DURING THE DAYTIME PERIOD. DUE TO THE QUICK NATURE OF THE SYSTEM AND GENERAL LACK OF MOISTURE AMOUNTS SHOULD BE VERY LIGHT. .LONG TERM...(SUNDAY THROUGH NEXT THURSDAY) ISSUED AT 1256 AM MST THU JAN 9 2014 SHORTWAVE TROUGH MOVING THROUGH ON SUNDAY WILL BRING LOW PROBABILITIES OF LIGHT PRECIPITATION. THE REMAINDER OF THE LONG TERM PERIOD WILL BE DRY AS A RIDGE OVER THE WEST SLOWLY MIGRATES TO THE CENTRAL PLAINS. TEMPERATURES WILL BE ABOVE NORMAL. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 1036 AM MST THU JAN 9 2014 LIGHT FOG IS STILL BEING REPORTED AT SOME LOCATIONS ACROSS NORTHWEST KS AND SOUTHWEST NEBRASKA WITH MVFR VIS. AT THIS POINT VFR CONDITIONS SHOULD PREVAIL THROUGH THE REST OF THE AFTERNOON BASED ON LATEST SATELLITE/OBS TRENDS AT BOTH KGLD AND KMCK...THOUGH BRIEF DROPS TO NEAR 5-6SM AT KMCK COULD NOT BE RULED OUT NEAR THE VALID TAF TIME. WILL KEEP MENTION OUT FOR NOW SINCE CONFIDENCE IN VFR CONDITIONS IS HIGHER...AND THESE CONDITIONS WOULD BE VERY BRIEF. FOG MAY REDEVELOP LATE TONIGHT ACROSS CENTRAL KS AND ADVECT NORTH TO BE NEAR KMCK. AT THIS TIME VFR CONDITIONS SHOULD PREVAIL...THOUGH WE MAY SEE A BRIEF PERIOD OF 3-5SM VIS AT KMCK AFTER 06Z. JUST NOT A HIGH ENOUGH CHANCE AT THE TERMINAL TO INCLUDE IN THIS UPDATE. AS AN UPPER LEVEL SYSTEM MOVES INTO THE REGION WINDS SHOULD SHIFT FROM THE SOUTH TO THE WEST AFTER 06Z WITH GUSTS AROUND 25KT AT BOTH TERMINALS. WINDS WILL LIKELY REMAIN BELOW 12KT AT KMCK UNTIL CLOSER TO 12-14Z BASED ON CURRENT GUIDANCE. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...DR LONG TERM...024 AVIATION...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1036 AM MST THU JAN 9 2014 .UPDATE... ISSUED AT 834 AM MST THU JAN 9 2014 UPDATED FORECAST A LITTLE BIT EARLIER AND ISSUED NOWCAST TO ACCOUNT FOR COVERAGE OF FOG AND ISOLATED POCKETS OF DENSE/FREEZING FOG. WHILE THE HRRR APPEARS TO HAVE A DECENT HANDLE ON CURRENT LOCATION OF DENSE FOG...I AN SCEPTICALLY OF ITS TREND TO OVERSPREAD THE CWA WITH DENSE FOG BY 18Z AND LINGER THESE CONDITIONS INTO THE AFTERNOON. RAP SHOW CONDITIONS IMPROVING FROM THE WEST/NORTHWEST WHICH WOULD MATCH THE EXPECTED CHANGES IN THE SURFACE PATTER AS THE SURFACE TROUGH IN COLORADO SHIFTS EAST AND BL CONDITIONS MODIFY. COULD STILL SEE LINGERING FOG FURTHER EAST WHERE BL MOISTURE ADVECTION WILL BE SUPPORTED INTO THE AFTERNOON...AND TEMPS WILL BE SLOWER TO RECOVER. && .SHORT TERM...(TODAY THROUGH SATURDAY NIGHT) ISSUED AT 233 AM MST THU JAN 9 2014 THE SHORT TERM FORECAST FOCUS IS ON THE SURFACE TROUGH EXPECTED TO MOVE ACROSS THE FORECAST AREA OVERNIGHT TONIGHT WITH THE UPPER TROUGH FOLLOWING CLOSELY BEHIND ON FRIDAY. OVERNIGHT LOW CLOUDS AND AREAS OF FOG ARE EXPECTED TO DISSIPATE QUICKLY FOLLOWING SUNRISE THIS MORNING AS SURFACE WINDS BEGIN TO TURN SOUTHWEST AND INCREASE WITH THE DEEPENING SURFACE TROUGH ALONG THE FRONT RANGE. THIS SURFACE SOUTHWEST FLOW WILL HELP HIGH TEMPERATURES WARM TO 5-10 DEGREES WARMER THAN YESTERDAY ACROSS MUCH OF THE FORECAST AREA. THE SURFACE TROUGH MOVES THROUGH THE FORECAST AREA AROUND 09Z EARLY FRIDAY MORNING WITH WINDS TURNING NORTHWEST AND BECOMING GUSTY. MOISTURE INCREASES THROUGH THE COLUMN AS THE UPPER TROUGH MOVES THROUGH...SO EXPECT CLOUDY SKIES FROM EARLY FRIDAY MORNING THROUGH THE EARLY AFTERNOON...BUT EXPECT LITTLE IN THE WAY OF PRECIPITATION DUE TO THE PROGRESSIVE NATURE OF THE TROUGH. THERE IS A SLIGHT CHANCE OF PRECIPITATION MAINLY NORTH OF INTERSTATE 70 WITH LIGHT SNOW POSSIBLE EARLY FRIDAY MORNING ACROSS THE NORTHWEST PORTION OF THE FORECAST AREA THAT WILL TURN TO A RAIN/SNOW MIX AND THEN LIGHT RAIN ACROSS THE NORTHEAST PORTION OF THE FORECAST AREA DURING THE DAY ON FRIDAY. SKIES SHOULD CLEAR QUICKLY BEHIND THE EXITING TROUGH BY LATE FRIDAY AFTERNOON AND EARLY EVENING. WITH AN UPPER RIDGE MOVING EAST OF THE ROCKIES ON FRIDAY NIGHT AND SATURDAY...SKIES SHOULD BE MOSTLY CLEAR WITH DRY CONDITIONS...GOOD HEATING AND HIGH TEMPERATURES REACHING INTO THE LOWER 50S DURING THE DAY. .LONG TERM...(SUNDAY THROUGH NEXT THURSDAY) ISSUED AT 1256 AM MST THU JAN 9 2014 SHORTWAVE TROUGH MOVING THROUGH ON SUNDAY WILL BRING LOW PROBABILITIES OF LIGHT PRECIPITATION. THE REMAINDER OF THE LONG TERM PERIOD WILL BE DRY AS A RIDGE OVER THE WEST SLOWLY MIGRATES TO THE CENTRAL PLAINS. TEMPERATURES WILL BE ABOVE NORMAL. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 1036 AM MST THU JAN 9 2014 LIGHT FOG IS STILL BEING REPORTED AT SOME LOCATIONS ACROSS NORTHWEST KS AND SOUTHWEST NEBRASKA WITH MVFR VIS. AT THIS POINT VFR CONDITIONS SHOULD PREVAIL THROUGH THE REST OF THE AFTERNOON BASED ON LATEST SATELLITE/OBS TRENDS AT BOTH KGLD AND KMCK...THOUGH BRIEF DROPS TO NEAR 5-6SM AT KMCK COULD NOT BE RULED OUT NEAR THE VALID TAF TIME. WILL KEEP MENTION OUT FOR NOW SINCE CONFIDENCE IN VFR CONDITIONS IS HIGHER...AND THESE CONDITIONS WOULD BE VERY BRIEF. FOG MAY REDEVELOP LATE TONIGHT ACROSS CENTRAL KS AND ADVECT NORTH TO BE NEAR KMCK. AT THIS TIME VFR CONDITIONS SHOULD PREVAIL...THOUGH WE MAY SEE A BRIEF PERIOD OF 3-5SM VIS AT KMCK AFTER 06Z. JUST NOT A HIGH ENOUGH CHANCE AT THE TERMINAL TO INCLUDE IN THIS UPDATE. AS AN UPPER LEVEL SYSTEM MOVES INTO THE REGION WINDS SHOULD SHIFT FROM THE SOUTH TO THE WEST AFTER 06Z WITH GUSTS AROUND 25KT AT BOTH TERMINALS. WINDS WILL LIKELY REMAIN BELOW 12KT AT KMCK UNTIL CLOSER TO 12-14Z BASED ON CURRENT GUIDANCE. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ UPDATE...DR SHORT TERM...LOCKHART LONG TERM...024 AVIATION...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
835 AM MST THU JAN 9 2014 .UPDATE... ISSUED AT 834 AM MST THU JAN 9 2014 UPDATED FORECAST A LITTLE BIT EARLIER AND ISSUED NOWCAST TO ACCOUNT FOR COVERAGE OF FOG AND ISOLATED POCKETS OF DENSE/FREEZING FOG. WHILE THE HRRR APPEARS TO HAVE A DECENT HANDLE ON CURRENT LOCATION OF DENSE FOG...I AN SCEPTICALLY OF ITS TREND TO OVERSPREAD THE CWA WITH DENSE FOG BY 18Z AND LINGER THESE CONDITIONS INTO THE AFTERNOON. RAP SHOW CONDITIONS IMPROVING FROM THE WEST/NORTHWEST WHICH WOULD MATCH THE EXPECTED CHANGES IN THE SURFACE PATTER AS THE SURFACE TROUGH IN COLORADO SHIFTS EAST AND BL CONDITIONS MODIFY. COULD STILL SEE LINGERING FOG FURTHER EAST WHERE BL MOISTURE ADVECTION WILL BE SUPPORTED INTO THE AFTERNOON...AND TEMPS WILL BE SLOWER TO RECOVER. && .SHORT TERM...(TODAY THROUGH SATURDAY NIGHT) ISSUED AT 233 AM MST THU JAN 9 2014 THE SHORT TERM FORECAST FOCUS IS ON THE SURFACE TROUGH EXPECTED TO MOVE ACROSS THE FORECAST AREA OVERNIGHT TONIGHT WITH THE UPPER TROUGH FOLLOWING CLOSELY BEHIND ON FRIDAY. OVERNIGHT LOW CLOUDS AND AREAS OF FOG ARE EXPECTED TO DISSIPATE QUICKLY FOLLOWING SUNRISE THIS MORNING AS SURFACE WINDS BEGIN TO TURN SOUTHWEST AND INCREASE WITH THE DEEPENING SURFACE TROUGH ALONG THE FRONT RANGE. THIS SURFACE SOUTHWEST FLOW WILL HELP HIGH TEMPERATURES WARM TO 5-10 DEGREES WARMER THAN YESTERDAY ACROSS MUCH OF THE FORECAST AREA. THE SURFACE TROUGH MOVES THROUGH THE FORECAST AREA AROUND 09Z EARLY FRIDAY MORNING WITH WINDS TURNING NORTHWEST AND BECOMING GUSTY. MOISTURE INCREASES THROUGH THE COLUMN AS THE UPPER TROUGH MOVES THROUGH...SO EXPECT CLOUDY SKIES FROM EARLY FRIDAY MORNING THROUGH THE EARLY AFTERNOON...BUT EXPECT LITTLE IN THE WAY OF PRECIPITATION DUE TO THE PROGRESSIVE NATURE OF THE TROUGH. THERE IS A SLIGHT CHANCE OF PRECIPITATION MAINLY NORTH OF INTERSTATE 70 WITH LIGHT SNOW POSSIBLE EARLY FRIDAY MORNING ACROSS THE NORTHWEST PORTION OF THE FORECAST AREA THAT WILL TURN TO A RAIN/SNOW MIX AND THEN LIGHT RAIN ACROSS THE NORTHEAST PORTION OF THE FORECAST AREA DURING THE DAY ON FRIDAY. SKIES SHOULD CLEAR QUICKLY BEHIND THE EXITING TROUGH BY LATE FRIDAY AFTERNOON AND EARLY EVENING. WITH AN UPPER RIDGE MOVING EAST OF THE ROCKIES ON FRIDAY NIGHT AND SATURDAY...SKIES SHOULD BE MOSTLY CLEAR WITH DRY CONDITIONS...GOOD HEATING AND HIGH TEMPERATURES REACHING INTO THE LOWER 50S DURING THE DAY. .LONG TERM...(SUNDAY THROUGH NEXT THURSDAY) ISSUED AT 1256 AM MST THU JAN 9 2014 SHORTWAVE TROUGH MOVING THROUGH ON SUNDAY WILL BRING LOW PROBABILITIES OF LIGHT PRECIPITATION. THE REMAINDER OF THE LONG TERM PERIOD WILL BE DRY AS A RIDGE OVER THE WEST SLOWLY MIGRATES TO THE CENTRAL PLAINS. TEMPERATURES WILL BE ABOVE NORMAL. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING) ISSUED AT 328 AM MST THU JAN 9 2014 VFR CONDITIONS ARE EXPECTED AT GLD THROUGH THE TAF PERIOD WITH MID TO HIGH CLOUDS THAT WILL INCREASE THROUGH THE LATE AFTERNOON AND OVERNIGHT HOURS. SOUTH WINDS WILL TURN SOUTHWEST LATE THIS AFTERNOON AND EVENING AHEAD OF THE SURFACE TROUGH THAT WILL MOVE THROUGH AROUND 09Z. AFTER 09Z...GUSTY NORTHWEST WINDS ARE EXPECTED. AT MCK...PATCHY FOG AND MVFR CONDITIONS WILL BE OBSERVED FOR A COUPLE HOURS AT THE BEGINNING OF THE TAF PERIOD THIS MORNING. LIGHT SOUTHEAST WINDS WILL TURN SOUTH AFTER 14Z WITH CONDITIONS BECOMING VFR AFTER 14Z. WINDS WILL TURN SOUTHWEST THROUGH THE LATE AFTERNOON AND EVENING AHEAD OF THE SURFACE TROUGH THAT IS EXPECTED IN THE VICINITY RIGHT AROUND THE END OF THE TAF PERIOD BETWEEN 10-12Z FRIDAY MORNING. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ UPDATE...DR SHORT TERM...LOCKHART LONG TERM...024 AVIATION...LOCKHART
AREA FORECAST DISCUSSION
NWS WICHITA KS
331 AM CST THU JAN 9 2014 .SHORT TERM...(TODAY THROUGH FRIDAY) ISSUED AT 327 AM CST THU JAN 9 2014 TODAY-TONIGHT: WIDESPREAD STRATUS AND PATCHY DRIZZLE/FREEZING DRIZZLE CONTINUES OVER MOST OF SOUTHERN KANSAS AT THIS TIME. SOME MID LEVEL CLOUDS ASSOCIATED WITH THE SHORTWAVE THAT HAS INCREASED THE LOW LEVEL MOISTURE ACROSS THE AREA...HAS ACTUALLY LED TO A LITTLE SEEDER FEEDER LIGHT SNOW TO MIX WITH THE DRIZZLE OVER SOUTHEAST KANSAS AS WELL. THE SHORTWAVE/WEAK LIFT WILL GRADUALLY BEGIN TO SHIFT EAST AS THE EARLY MORNING PROGRESSES...WHICH WILL BASICALLY END THE CHANCE OF DRIZZLE/FREEZING DRIZZLE ACROSS THE AREA FROM WEST TO EAST. SO HAVE DECIDED TO END THE WINTER WEATHER ADVISORY FOR AREAS WEST OF THE KANSAS TURNPIKE...AS THIS AREA WILL HAVE A DIMINISHING CHANCE OF DRIZZLE DEVELOPING. WILL KEEP THE ADVISORY GOING FOR WILL SEE THE LOW CLOUDS REMAIN AROUND FOR MOST OF THE DAY...AS RETURN SURFACE FLOW GRADUALLY SHIFTS BACK TO THE SOUTHEAST AND SOUTH FOR THE AFTERNOON AND EVENING HOURS. THIS UPSLOPE COMPONENT WILL KEEP THE LOW CLOUDS ACROSS THE AREA INTO THE OVERNIGHT HOURS AS WELL. FRIDAY: THE NEXT SYSTEM TO AFFECT THE PLAINS...WHICH IS CURRENTLY OVER THE PACIFIC NORTHWEST...WILL DROP SOUTHEAST AND MOVE INTO THE PLAINS FOR FRIDAY. A LOT BETTER MOISTURE TRANSPORT AND DYNAMICS ASSOCIATED WITH THIS SYSTEM AS IT PULLS INTO THE PLAINS...WHICH WILL LEAD TO STRONGER WARM ADVECTION/MOISTURE TRANSPORT AND A BETTER PRECIPITATION CHANCE FOR AREAS EAST OF INTERSTATE 135 FOR THE DAYTIME HOURS ON FRIDAY. LATEST MODEL TRENDS HAVE BEEN MORE PROGRESSIVE WITH THIS SYSTEM...WHICH HAS ALSO LED TO MOST OF THE PRECIPITATION ASSOCIATED WITH IT GETTING SHUNTED FURTHER EAST WITH EACH RUN. SO HAVE DIMINISHED POPS FOR AREAS WEST OF INTERSTATE 135 SOME. THIS SYSTEM WILL CERTAINLY HAVE A SOLID CHANCE OF PRECIPITATION... BUT MORNING SURFACE TEMPS ON FRIDAY...MAY MAKE ONSET OF PRECIPITATION A LITTLE TRICKY WHEN IT COMES TO PRECIPITATION TYPE. SURFACE TEMPS MAY BE JUST BELOW FREEZING...WHEN PRECIPITATION BEGINS...WHICH MAY LEAD TO A PERIOD OF FREEZING DRIZZLE/FREEZING RAIN FOR THE EARLY MORNING HOURS ON FRIDAY. ESPECIALLY FOR AREAS NORTH OF HIGHWAY 50. BUT EXPECT THE STRONG WARM ADVECTION TO CHANGE MOST OF THE PRECIPITATION QUICKLY TO RAIN...AS THE MORNING PROGRESSES. THE ONLY AREA THAT COULD SEE AN EXTENDED PERIOD OF FREEZING RAIN MAY BE ALONG THE INTERSTATE 70 CORRIDOR UNTIL AROUND NOON TIME FRIDAY...WITH ANY GLAZING ON ELEVATED SURFACES. WITH EASTWARD PUSH OF THE MAIN RAIN SWATH...THINK HEAVIEST QUANTITATIVE PRECIPITATION WILL ALSO BE PUSHED EAST INTO THE SOUTHEAST KANSAS AND SOUTHWEST MISSOURI. SO SOAKING RAIN CHANCE LOOKS TO BE DIMINISHING AS WELL FOR MOST OF THE FORECAST AREA. WILL HAVE TO KEEP AN EYE ON CENTRAL KANSAS...AS THIS AREA MAY NEED A WINTER ADVISORY WITH LATER FORECASTS...BECAUSE SOME AREAS MAY RECEIVE UP TO A TENTH OF AN INCH OF GLAZING. KETCHAM .LONG TERM...(SATURDAY THROUGH WEDNESDAY) ISSUED AT 327 AM CST THU JAN 9 2014 SATURDAY-SUNDAY: NOT ALOT OF COLD AIR AFTER THE FRIDAY SYSTEM MOVES THROUGH THE AREA...WITH PROGRESSIVE ZONAL FLOW LEADING TO A NICE WARMUP FOR THE WEEKEND. COULD SEE TEMPS ACTUALLY CLIMB ABOVE NORMAL FOR THE FIRST TIME IN OVER A WEEK FOR SATURDAY/SUNDAY. NEXT QUICK HITTING SHORTWAVE LOOKS TO MOVE OUT OF THE CENTRAL ROCKIES INTO THE PLAINS FOR SUNDAY AFTERNOON/EVENING. VERY LITTLE LOW LEVEL MOISTURE FOR THIS SYSTEM TO WORK WITH...WITH POSSIBLY JUST A SPRINKLE CHANCE AT BEST ACROSS CENTRAL KANSAS FOR SUNDAY EVENING. GOOD DOWNSLOPE CONDITIONS EXPECTED ACROSS THE AREA ON SUNDAY...SO BUMPED UP TEMPERATURES SOME FOR SUNDAY AFTERNOON INTO THE MIDDLE 50S. SOME MODEL SOLUTIONS EVEN SUGGESTING TEMPERATURES CLOSER TO 60 FOR HIGHS. SO WOULD NOT BE SURPRISED IF LATER MODEL RUNS/FORECASTS GO EVEN WARMER WITH SUNDAY TEMPERATURES. REST OF THE EXTENDED: THE GENERAL THEME FOR THE BEGINNING OF NEXT WEEK WILL BE DRIER AND SLIGHTLY ABOVE NORMAL TEMPERATURES AS MID LEVEL FLOW PATTERN BECOMES MORE NORTHWEST AS A LARGE UPPER RIDGE BUILDS OVER THE ROCKIES. ANOTHER SHOT OF COLDER AIR LOOKS TO MAKE A GLANCING BLOW FOR MOST OF KANSAS FOR TUESDAY...WHICH WILL DROP TEMPERATURES BACK TOWARDS NORMAL BUT MEDIUM RANGE MODELS DIFFER ON HOW STRONG THIS COLDER AIR WILL BE...BUT THE COLDEST AIR WILL STAY EAST OF THE AREA. KETCHAM && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING) ISSUED AT 1153 PM CST WED JAN 8 2014 MAINLY IFR AVIATION FORECAST. 0000 UTC RUNS OF NAM/GFS STILL APPEAR TO BE STRUGGLING WITH LOW LEVEL MOISTURE FIELDS...SIGNIFICANTLY LOWERING CONFIDENCE OF LATTER TWO THIRDS OF THE FORECAST. RUC AND TO A LESSER EXTENT THE HRRR...STILL HAVE THE BEST CORRELATION WITH ONGOING WEATHER/TRENDS. CHANGES FROM 0000 UTC TAFS ARE FOR A BIT SLOWER ONSET...AS SURFACE WINDS HAVE BEEN MUCH MORE NORTH COMPONENT AND ADVECTING DRIER AIR. AGAIN THIS IS A BIT SLOWER THAN PREVIOUS FORECAST. OPTED AGAIN TO BE QUITE STINGY WITH FZDZ FORECAST. WITH INFLUX OF MOISTURE/WARM AIR ADVECTION DURING THE DAY ON THU...NOT EXPECTING A QUICK IMPROVEMENT IN CONDITIONS AND RETURN TO IFR CONDITIONS AFTER 0000 UTC. -HOWERTON && .PRELIMINARY POINT TEMPS/POPS... WICHITA-KICT 35 33 43 28 / 10 30 50 10 HUTCHINSON 34 30 42 27 / 10 20 50 10 NEWTON 34 32 42 28 / 10 30 50 10 ELDORADO 35 34 44 28 / 10 30 60 10 WINFIELD-KWLD 36 34 47 30 / 10 30 60 10 RUSSELL 34 27 41 25 / 10 10 30 0 GREAT BEND 34 28 41 26 / 10 10 30 0 SALINA 33 28 40 27 / 10 20 50 10 MCPHERSON 33 30 41 27 / 10 20 50 10 COFFEYVILLE 37 35 49 31 / 20 50 80 30 CHANUTE 36 34 46 30 / 20 40 80 20 IOLA 35 34 46 30 / 20 40 80 20 PARSONS-KPPF 36 35 48 30 / 20 40 80 30 && .ICT WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY UNTIL 9 AM CST THIS MORNING FOR KSZ071- 072-095-096-099-100. && $$
AREA FORECAST DISCUSSION
NWS WICHITA KS
1155 PM CST WED JAN 8 2014 .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 241 PM CST WED JAN 8 2014 LOW LEVEL MOISTURE ADVECTION AND NORTHWARD DEVELOPMENT OF STRATUS IS UNDERWAY INTO SOUTHEAST AND SOUTH CENTRAL KANSAS THIS AFTERNOON AND WILL CONTINUE ACROSS MUCH OF THE AREA TONIGHT AHEAD OF THE APPROACHING SHORTWAVE UPPER TROF. DRIZZLE HAS ALREADY DEVELOPED ACROSS OKLAHOMA WITH A SIMILAR OUTCOME ACROSS MUCH OF THE AREA TONIGHT. HOWEVER WITH SURFACE TEMPERATURES DROPPING BELOW FREEZING THIS WILL RESULT IN DEPOSITION OF A LIGHT GLAZE ON ELEVATED SURFACES AND UNTREATED ROADS. HIGHEST CONFIDENCE ON THIS IS COVERED WELL WITH THE CURRENT WINTER WEATHER ADVISORY...HOWEVER A FURTHER EXPANSION TO THE NORTHWEST INTO PARTS OF CENTRAL KANSAS IS POSSIBLE LATER THIS EVENING. SOME FREEZING FOG WITH LOCALLY LOW VISIBILITIES ARE ALSO POSSIBLE BY EARLY THURSDAY MORNING BEFORE DAWN ACROSS PORTIONS OF CENTRAL KANSAS ON THE WESTERN PERIPHERY OF THE FREEZING DRIZZLE. THE NEXT CHALLENGE COMES ON THURSDAY NIGHT INTO FRIDAY AS THE STRONGER PACIFIC UPPER TROF DIVES SOUTHEAST ACROSS THE ROCKIES AND INTO THE CENTRAL PLAINS. A BETTER FETCH OF MOISTURE AND LIFT WILL FOCUS ACROSS EASTERN KANSAS FOR FREEZING RAIN TO RAIN. THE LATEST GFS SHUNTS THE BETTER MOISTURE AND LIKEWISE QPF EAST QUICKER ACROSS SOUTHEAST KANSAS INTO MISSOURI ON FRIDAY...THOUGH THE NAM REMAINS MORE BULLISH AND THE ECMWF A BIT OF A COMPROMISE. FOR NOW HAVE MADE A SLIGHT DOWNWARD ADJUSTMENT TO POPS AND QPF ACROSS THE WESTERN HALF OF THE FORECAST AREA...THOUGH NOT NEARLY AS MUCH AS THE LATEST HPC GUIDANCE. A PERIOD OF FREEZING RAIN EARLY FRIDAY MORNING COULD RESULT IN SOME ICING...PRIMARILY ACROSS CENTRAL KANSAS...AND WILL CONTINUE TO BE WATCHED FOR A POSSIBLE FUTURE WINTER HEADLINE. SATURDAY LOOKS DRY AND SEASONABLY MILD WITH TEMPERATURES A BIT ABOVE CLIMO FOR A CHANGE. DARMOFAL .LONG TERM...(SUNDAY THROUGH WEDNESDAY) ISSUED AT 241 PM CST WED JAN 8 2014 WHILE THE MEDIUM RANGE MODELS STILL SUPPORT A DRY AND MILDER FORECAST THROUGH EARLY NEXT WEEK...THERE ARE SOME TIMING DIFFERENCES WITH MIGRATORY SHORTWAVE TROFS WHICH WILL AFFECT DAILY TEMPERATURE TRENDS. THE GFS IS MORE PROGRESSIVE WITH A TROF ON SUNDAY WHICH SUGGESTS A FASTER FRONTAL PASSAGE. A CHALLENGE BY MID-WEEK WILL BE THE POTENTIAL FOR A STRONGER NORTHERN STREAM TROF WITHIN THE DEVELOPING EASTERN CONUS LONGWAVE TUESDAY INTO WEDNESDAY. THIS MAY ALLOW A BIT COLDER AIR THAN ADVERTISED TO ADVECT SOUTH ACROSS EASTERN KANSAS. DARMOFAL && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT) ISSUED AT 1153 PM CST WED JAN 8 2014 MAINLY IFR AVIATION FORECAST. 0000 UTC RUNS OF NAM/GFS STILL APPEAR TO BE STRUGGLING WITH LOW LEVEL MOISTURE FIELDS...SIGNIFICANTLY LOWERING CONFIDENCE OF LATTER TWO THIRDS OF THE FORECAST. RUC AND TO A LESSER EXTENT THE HRRR...STILL HAVE THE BEST CORRELATION WITH ONGOING WEATHER/TRENDS. CHANGES FROM 0000 UTC TAFS ARE FOR A BIT SLOWER ONSET...AS SURFACE WINDS HAVE BEEN MUCH MORE NORTH COMPONENT AND ADVECTING DRIER AIR. AGAIN THIS IS A BIT SLOWER THAN PREVIOUS FORECAST. OPTED AGAIN TO BE QUITE STINGY WITH FZDZ FORECAST. WITH INFLUX OF MOISTURE/WARM AIR ADVECTION DURING THE DAY ON THU...NOT EXPECTING A QUICK IMPROVEMENT IN CONDITIONS AND RETURN TO IFR CONDITIONS AFTER 0000 UTC. -HOWERTON && .PRELIMINARY POINT TEMPS/POPS... WICHITA-KICT 25 35 31 43 / 20 10 50 70 HUTCHINSON 21 34 29 42 / 20 10 50 60 NEWTON 22 34 30 42 / 20 10 50 70 ELDORADO 23 35 30 44 / 30 10 50 80 WINFIELD-KWLD 26 36 32 47 / 30 10 60 80 RUSSELL 16 34 26 41 / 10 10 20 40 GREAT BEND 17 34 27 41 / 10 10 30 40 SALINA 14 33 27 40 / 20 10 30 60 MCPHERSON 20 33 29 41 / 20 10 40 60 COFFEYVILLE 28 37 32 49 / 40 20 60 90 CHANUTE 26 36 31 46 / 40 20 50 90 IOLA 25 35 31 46 / 40 20 40 90 PARSONS-KPPF 28 36 32 48 / 40 20 50 90 && .ICT WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY UNTIL 9 AM CST THURSDAY FOR KSZ069>072- 083-092>096-098>100. && $$
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
913 PM EST FRI JAN 10 2014 .SYNOPSIS... HIGH PRESSURE MOVES OFFSHORE TODAY AND TONIGHT AS A SERIES OF WEAK UPPER LEVEL TROUGHS TRACK ACROSS THE MID ATLANTIC REGION. A COLD FRONT APPROACHES FROM THE WEST SATURDAY AND PUSHES THROUGH THE REGION SATURDAY NIGHT EVENING. HIGH PRESSURE RETURNS FROM THE WEST LATER SATURDAY NIGHT INTO SUNDAY. && .NEAR TERM /UNTIL 6 AM SATURDAY MORNING/... LATEST SURFACE ANALYSIS INDICATES A ~1034MB SFC HIGH PRESSURE NOW WELL OFF THE NEW ENGLAND COASTLINE...WITH A SFC RIDGE AXIS EXTENDING SW ALONG THE PIEDMONT INTO NE GA. TO THE SOUTHEAST, A COASTAL TROUGH HAS NOW LIFTED INLAND ACROSS THE COASTAL CAROLINAS...AND BRIEFLY LIFTED ACROSS FAR SE TIP OF THE COMMONWEALTH EARLY THIS AFTN (TEMPS JUMPED INTO THE LOW 60S EARLY THIS AFTN BEFORE DROPPING BACK INTO THE U40S OVER THE PAST FEW HRS). WARM/MOIST ADVECTION CONTINUES THIS AFTN...WITH SHRAS IN ASSN WITH THE LATEST SLUG OF OVERRUNNING MOISTURE MOVING ACROSS THE REGION ATTM. WV SAT IMAGERY SHOWING DISTURBANCE RESPONSIBLE FOR THIS LATEST ROUND OF SHRAS LIFTING E-NE ACROSS THE LOWER MID- ATLANTIC IN SSW FLOW ALOFT. OCCASIONAL LIGHT RAINFALL WILL CONTINUE OVER THE NEXT FEW HOURS AS THIS WAVE MOVES THROUGH...WITH SHRAS BECOMING LESS WIDESPREAD LATE TONIGHT AND ESPECIALLY AFTER MIDNIGHT AS FRONT SHIFTS NORTH. FOR TEMPS, WE`VE FOLLOWED THE LEAD OF THE HRRR AND HIGH RES NAM W/TEMP TRENDS THROUGH EARLY SAT MORNING. EXPECT TEMPS WILL FALL VERY LITTLE EARLY TONIGHT ACROSS CENTRAL AND NORTHERN ZONES...LIKELY RISING GRADUALLY TOWARD MORNING AS THE WARM FRONT LIFTS NORTH ACROSS AREA. CONSIDERING THE LIGHT WINDS, THIS WILL ALSO BRING WIDESPREAD STRATUS/AREAS OF FOG INLAND EARLY TONIGHT THROUGH EARLY SATURDAY MORNING. && .SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY/... WEEKEND GETS OFF TO A VERY WET START, WITH HIGH CONFIDENCE OF A STEADY AND LOCALLY HEAVY RAINFALL ON SATURDAY. DEEP MOISTURE THROUGH 300MB COMBINED WITH STRONG LIFT SHOULD PRODUCE MODERATE TO OCCASIONALLY HEAVY RAIN BY AFTN. HOWEVER...QPF SHOULD LARGELY AVG 0.75-1.25" DUE TO THE QUICK MOTION OF THE SYSTEM. TEMPERATURES SHOULD BE VERY MILD, AS THE SURFACE WARM FRONT SURGES N OF THE LOCAL AREA EARLY IN THE DAY. BREEZY CONDITIONS DEVELOP FOR THE EASTERN THIRD OF THE AREA...WITH A S WIND OF 15-20MPH IN THE WARM SECTOR, WITH GUSTS TO AROUND 30MPH EXPECTED. FORECAST HIGHS WILL RANGE FROM THE U50S/L60S IN THE MODIFIED WEDGE AIRMASS ACROSS THE FAR NW TIER...WITH MID 60S TO AROUND 70 OVER THE I-95 CORRIDOR AND THE LOWER EASTERN SHORE...AND LOW 70S ACROSS FAR EASTERN VA AND INTERIOR NE NC. SEE CLIMATE SECTION BELOW...AS A FEW RECORD HIGHS FOR THE DATE APPEAR ATTAINABLE. SREF CONTINUES TO ADVERTISE 90+% CONFIDENCE IN 2M DEWPOINT VALUES AOA 60F ACROSS CENTRAL/EASTERN SECTIONS. THIS COULD LEAD TO ISOLATED THUNDERSTORMS SAT AFTN, PRIMARILY SOUTH AND EAST OF RIC /TRI- CITIES AREA TOWARDS HAMPTON ROADS/TIDEWATER AREAS. GOOD MODEL AGREEMENT IN DEPICTION OF STRONG LIFT (UPRIGHT FRONTOGENESIS) FROM THE SURFACE TO ~850MB ON MODEL CROSS SECTIONS PER THE GFS/NAM SAT AFTN. THIS IS PROGGED TO OCCUR IN A SYNOPTIC ENVIRONMENT FEATURING A 65-70KT LLJ...50-60KT OF SW 0-6KM BULK SHEAR...AND 500-700 J/KG MLCAPE. GIVEN THIS COMBINATION OF SYNOPTIC AND MESOSCALE FACTORS...THERE IS A HIGH CONFIDENCE IN WIDESPREAD MOD RAINFALL (FALLING HEAVILY AT TIMES). HOWEVER, THERE IS ALSO POTENTIAL FOR A FORCED LINE OF LOW-TOPPED CONVECTION (RARE BUT NOT UNPRECEDENTED FOR JANUARY) CAPABLE OF MIXING DOWN SOME STRONG TO POTENTIALLY DAMAGING WIND GUSTS. AREA OF CONCERN REMAINS MAINLY ACROSS THE AFOREMENTIONED AREAS OF S-CENTRAL/SE VA AND NE NC. BASED ON THE LATEST 12Z/10 DATA...THE TIMING OF THE GREATEST THREAT WOULD BE AFTER 18Z/1P SAT AFTERNOON INTO EARLY EVENING. SE PORTIONS OF THE AREA REMAIN HIGHLIGHTED IN A DAY 2 SLIGHT RISK BY THE SPC...AND WILL CONTINUE TO HIGHLIGHT THIS AREA IN THE HWO. A TRANSITION DAY SUNDAY AND EARLY MONDAY AS UPPER TROUGH PIVOTS OFFSHORE AND QUASI-ZONAL FLOW BRINGS A CLEARING SKY. WHILE NOT NEARLY AS MILD AS SATURDAY, MAXIMA REMAIN ~1 S.D. ABOVE NORMAL...CLIMBING INTO THE MID 50S TO NEAR 60 FOR MOST. EARLY MORNING LOWS MONDAY IN THE 30S TO NEAR 40. FLOW ALOFT BECOMES INCREASINGLY SW ON MONDAY...WITH GRADUALLY INCREASING HIGH CLOUDS LATER IN THE DAY AS AN UPPER LEVEL TROUGH BARRELS EASTWARD FROM THE PLAINS MONDAY THROUGH MONDAY NIGHT. ECMWF IS A BIT MORE AGGRESSIVE WITH THIS FEATURE THAN THE GFS. FOR NOW, HAVE PLAYED TOWARDS THE DRIER/WEAKER GFS SOLUTION...WITH WARM SW FLOW ALLOWING MAXIMA TO WARM BACK INTO THE U50S TO L60S. && .LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/... MEDIUM RANGE MODELS IN GENERAL AGREEMENT WITH AMPLIFIED...BUT PROGRESSIVE UPPER LEVEL PATTERN THROUGH THE EXTENDED PERIOD. HOWEVER...MODELS CONTINUE TO STRUGGLE WITH MID-LEVEL FEATURES DOWNSTREAM OF A LONGWAVE TROUGH OVER THE ERN CONUS. LONGWAVE TROUGH WILL PROGRESS EWD OVER THE CENTRAL CONUS MON NIGHT-TUES AS SHORTWAVE ENERGY ROUNDS THE BASE OF THE TROUGH AND EJECTS NEWD FROM THE DEEP SOUTH. SHORTWAVE ENERGY WILL EJECT FROM THE DEEP SOUTH TUES MORNING OVER THE MID- ATLANTIC TUES AFTERNOON. ECMWF IS MUCH STRONGER WITH THE SHORTWAVE ENERGY AND SWLY FLOW WHICH WOULD ADVECT DEEPER MOISTURE INTO THE REGION IN ADVANCE OF A COLD FRONT. MEANWHILE...GFS IS MUCH WEAKER WITH THE ENERGY AND HAS LIMITED MOISTURE. SFC PATTERNS ALSO QUITE DIFFERENT AS SFC LOW PRESSURE CROSSES THE OH VALLEY. HAVE TRENDED CURRENT FORECAST TOWARD THE ECMWF...BUT MAINTAINED SOME GFS GUIDANCE TO ACCOUNT FOR UNCERTAINTIES. THE RESULT IS CHANCE POPS ACROSS THE REGION BEGINNING TUES MORNING INTO TUES AFTERNOON AS THE SYSTEM LIFTS OVER THE REGION. COLD FRONT/MOISTURE WILL PUSH OFFSHORE LATE TUES BRINGING AN END TO THE PRECIP. BASE OF THE TROUGH WILL EXTEND INTO THE DEEP SOUTH TUES NIGHT-WEDS MORNING AS AN ASSOCIATED STRONGER COLD FRONT MOVES INTO THE REGION. UPPER DYNAMICS WILL DEVELOP A WAVE ALONG THE FRONT...LEADING TO CYCLOGENESIS OVER THE LOCAL AREA TO JUST OFFSHORE EARLY WEDS. MOISTURE WILL BE RATHER LIMITED/SHALLOW...BUT BASED ON DYNAMICS...SLIGHT CHANCE POPS ARE WARRANTED ATTM. TROUGH AXIS WILL PUSH OFFSHORE WED NIGHT-THURS MORNING AS SFC HIGH PRESSURE BUILDS EWD OVER THE DEEP SOUTH...RIDGING NWD INTO THE LOCAL AREA. NRN STREAM WILL REMAIN ACTIVE AS ANOTHER SHORTWAVE DIGS OVER THE GREAT LAKES REGION LATE THURS-FRI...PUSHING A COLD FRONT ACROSS THE OH VALLEY INTO THE MID-ATLANTIC REGION FRI. UNCERTAINTY IS QUITE HIGH THIS FAR OUT...SO HAVE LEFT THE END OF THE WORK WEEK DRY. HIGH TEMPS WILL WARM ABOVE NORMAL TUES (UPPER 50S-LOW 60S) BEFORE FALLING BACK TO SEASONABLE NORMS THRU THE EXTENDED. MILD MON NIGHT (LOW-MID 40S) BEFORE RETURNING TO NEAR OR SLIGHTLY ABOVE SEASONABLE LOWS (LOW-MID 30S) THRU THE EXTENDED. && .AVIATION /02Z SATURDAY THROUGH WEDNESDAY/... LIGHT RAIN DRIZZLE AND FOG WILL CONTINUE ACROSS THE AREA THROUGH TONIGHT. FRONT AT 02Z JUST WEST OF ORF AND EXPECTED TO SLOWLY MOVE W-NW THRU THE NIGHT. SITES NORTH AND WEST OF A WARM FRONT (KRIC) ARE EXPERIENCING IFR CONDITIONS AND WILL CONTINUE TO DO SO UNTIL THE WARM FRONT LIFTS THROUGH THOSE AREAS. ECG/ORF/PHF/SBY NOW REPORTING MID CLOUD CIGS. WINDS WILL INCREASE THRU THE NIGHT AND BE GUSTY 20-25KT ON SAT AS PRESSURE GRADIENT TIGHTENS BETWEEN APPROACHING FRONT FROM THE WEST AND HIGH PRESSURE OFFSHORE. SHOWERS AND CHC OF TSTMS PSBL SAT AFTN AS TEMP RISE WITH STRONG SOUTHERLY FLOW AND INSTABILITY INCREASES. OUTLOOK...PERIODS OF RAIN AND WIDESPREAD MVFR/OCNL IFR CONDITIONS AND GUSTY WINDS SAT AFTN AS FRONT APPROACHES. DRY AND VFR CONDITIONS SUNDAY AND MONDAY THEN DETERIORATING CONDS ONCE AGAIN AROUND TUESDAY. && .MARINE... HIGH PRESSURE HAS LOCATED OVER THE WRN ATLANTIC THIS AFTERNOON. FLOW WILL TURN TO THE SOUTH AND INCREASE BEHIND A LIFTING WARM FRONT TONIGHT. GRADIENT WILL STRENGTHENS AS LOW PRESSURE AND AN ASSOCIATED COLD FRONT APPROACH FROM THE WEST. LOW-LEVEL WINDS (925MB) WILL INCREASE TO ~50 KT TONIGHT-SAT MORNING...BUT WAA/WEAK LAPSE RATES AND COLD WATERS WILL LIMIT THE HIGHER VELOCITY WINDS FROM REACHING THE WATER. HOWEVER...MODELS IN GOOD AGREEMENT FOR SOLID SCA CONDITIONS TONIGHT-SAT. SEAS WILL BUILD TO 5 TO 9 FT (UP TO 10+ FT 20 NM OUT IN THE NRN COASTAL WATERS). COLD FRONT WILL CROSS THE WATERS LATE SAT-EARLY SAT NIGHT AS WINDS BACK TO THE WEST AND REMAIN 15-20 KT OVER THE BAY/RIVERS AND 20-25 KT OVER THE COASTAL WATERS. A LINE OF CONVECTION IS EXPECTED ALONG THE COLD FRONT LATE SAT...WHICH MAY BRIEFLY PRODUCE GALE FORCE WINDS. HOWEVER...WILL LIKELY HANDLE THESE BRIEF/STRONG WINDS WITH SPECIAL MARINE WARNINGS INSTEAD OF GALE WORDING. HIGH PRESSURE WILL BUILD EWD OVER THE DEEP SOUTH SAT NIGHT-SUN...EXTENDING NWD OVER THE LOCAL AREA LATE SUN MORNING. THIS WILL ALLOW THE GRADIENT TO RELAX AND SPEEDS TO DIMINISH. AS HIGH PRESSURE PUSHES OFF THE SE COAST SUN NIGHT...FLOW WILL RETURN TO THE SOUTH. UNSETTLED CONDITIONS WILL RETURN TO THE WATERS TUES-WEDS. && .CLIMATE... RECORD HIGH TEMPERATURES SATURDAY JANUARY 11 RIC 72/1975 ORF 75/1974 SBY 68/1975 ECG 75/1974 && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...NONE. NC...NONE. VA...NONE. MARINE...SMALL CRAFT ADVISORY FROM 7 AM SATURDAY TO 6 AM EST SUNDAY FOR ANZ635>637. SMALL CRAFT ADVISORY FROM 4 AM SATURDAY TO 10 AM EST SUNDAY FOR ANZ632>634. SMALL CRAFT ADVISORY FROM 4 AM SATURDAY TO 6 AM EST SUNDAY FOR ANZ630-631. SMALL CRAFT ADVISORY FROM 7 AM SATURDAY TO 10 AM EST SUNDAY FOR ANZ638. SMALL CRAFT ADVISORY FROM 4 AM SATURDAY TO 4 PM EST SUNDAY FOR ANZ650-652-654-656-658. && $$ SYNOPSIS...MAM NEAR TERM...MAM SHORT TERM...AJZ/MAM LONG TERM...SAM AVIATION...DAP/JEF MARINE...SAM CLIMATE...
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
359 PM EST THU JAN 9 2014 .SHORT TERM... AFTERNOON AND TONIGHT AFTERNOON RADAR COMPOSITE AND SURFACE OBSERVATIONS INDICATE THE SNOW SHOWER PATTERN COMING TOGETHER WITH SOME GUSTO OVER NORTHERN INDIANA AND WESTERN OHIO. THE MID LEVEL SHORT WAVE SHOWN ON WATER VAPOR IMAGERY LOOKS QUITE DYNAMIC AND IS HELPING SHAPE UP THE WARM FRONT OVER THE OHIO VALLEY AT THE SURFACE AND ENHANCING ISENTROPIC LIFT TO THE NORTH OF THE FRONT INTO LOWER MICHIGAN. MODEL CROSS SECTIONS INDICATE THE SHORT WAVE INDUCED DCVA AND ISENTROPIC LIFT OCCURRING IN A LOW STABILITY ENVIRONMENT AND WITH A GENEROUS AMOUNT OF MOISTURE RESULTING IN THE STRONG VERTICAL MOTION RESPONSE. THE TEXTURE OF THE RADAR COMPOSITE EVEN SUGGESTS WEAK CONVECTIVE INSTABILITY ABOVE THE FRONTAL SURFACE, ROUGHLY IN THE 700-500 MB LAYER JUDGING FROM MODEL THETA-E PROFILES. THE LATEST RUNS OF THE NAM AND RAP HAVE A REASONABLE HANDLE ON THE EVOLUTION OF THE PATTERN AS THE WAVE SLIDES JUST SOUTH OF THE OHIO BORDER. THEY SHOW THE MOST INTENSE VERTICAL MOTION OCCURRING ROUGHLY ALONG AND SOUTH OF A LINE FROM HOWELL TO PORT HURON WITH A PEAK INTENSITY OCCURRING AROUND MID EVENING. THIS WILL CONSIST OF A GOOD COMBINATION OF LOW LEVEL ISENTROPIC LIFT AND MID LEVEL SHEARING DEFORMATION FUELED BY SPECIFIC HUMIDITY NEAR 3 G/KG. EXPECT THE RESULT TO BE WIDESPREAD LIGHT SNOW WITH IMBEDDED HEAVIER BURSTS ADDING UP TO ABOUT AN INCH OF ACCUMULATION AS FAR NORTH AS INTERSTATE 69. BOTH COVERAGE AND INTENSITY WILL BE LESS TOWARD THE TRI CITIES AND NORTHERN THUMB AND THEN WILL DIMINISH OVER THE SOUTH AFTER MIDNIGHT. STRONG MID LEVEL SUBSIDENCE TRAILING THE WAVE WILL THEN SET THE STAGE FOR FREEZING DRIZZLE POTENTIAL TOWARD SUNRISE. MODEL SOUNDINGS INDICATE SUBSIDENCE INDUCED MID LEVEL DRYING TAKING PLACE TOWARD 12Z WHICH WILL ELIMINATE ICE CRYSTAL NUCLEATION. THAT WILL LEAVE A FAVORABLE PROFILE FOR FREEZING DRIZZLE FORCED BY WIND SHEAR AND INSTABILITY AT THE TOP OF THE BOUNDARY LAYER/FRONTAL SLOPE. WHILE THE LARGE SCALE ENVIRONMENT IS SUPPORTIVE AND GROUND SURFACES ARE VERY COLD, UNCERTAINTY ON COVERAGE, DURATION, AND INTENSITY IS HIGH ENOUGH TO HOLD OFF ON HEADLINE ISSUANCE AT THIS POINT. OTHERWISE, THE STRONG NONDIURNAL TEMPERATURE TREND WILL HAVE MINS OCCURRING DURING EARLY EVENING FOLLOWED BY RISING TEMPS OVERNIGHT, BUT ONLY INTO THE LOWER AND MID 20S BY SUNRISE FRIDAY. && .LONG TERM...FRIDAY THROUGH SATURDAY NIGHT MAIN CONCERNS OVER THIS TIME PERIOD IS THE START TIME AND TYPE OF PRECIPITATION...ESPECIALLY FRIDAY AFTERNOON INTO EVENING BEFORE WARMER AIR WORKS UP INTO THE AREA. WEAK RIDGING AHEAD OF THE MAIN UPPER LEVEL TROUGH MOVING ACROSS THE AREA WILL ALLOW FOR A SLIGHT DOWNTURN IN THE PRECIP FRIDAY MORNING BEFORE MORE SUBSTANTIAL PRECIPITATION WORKS IN WITH THE NEXT LOW PRESSURE SYSTEM FRIDAY INTO SATURDAY. 120+ KNOT JET GETS GOING WITH THE LEFT ENTRANCE REGION MOVING OVER THE AREA. THIS JET THEN STRENGTHENS AS IT MOVES TO THE EAST OF THE AREA SATURDAY AFTERNOON. MODELS HAVE FINALLY COME INTO BETTER AGREEMENT ON THE TIMING AND DURATION OF THIS SYSTEM. AS THE LOW TRACKS NORTHEAST ACROSS WISCONSIN AND UPPER MICHIGAN...THIS WILL PULL A WARM FRONT UP THROUGH THE AREA FRIDAY BRINGING MOISTURE AND WARMER AIR TO SE MI. AS WITH THE CASE OF TRANSITIONING PRECIP TYPE THE BIGGEST CAVEAT WILL BE HOW LONG FREEZING DRIZZLE/RAIN LINGERS BEFORE THE WARMER AIR WORKS IN CHANGING PRECIP TO ALL RAIN. THIS TRANSITION DOES APPEAR TO BE OF SHORTER DURATION AS THE LOW LEVEL JET GETS GOING AND PUSHES IN THE WARMER AIR. SOUNDING PROFILES SHOW SATURATED LOW LEVELS WITH DRIER AIR IN THE MID LEVELS SUPPORTIVE OF DRIZZLE WITH THE ONSET OF PRECIP BEFORE MID LEVELS SATURATE. BETTER FORCING AND PRECIP CHANCES HOLD OFF UNTIL SATURDAY EVENING AS THE COLD FRONT APPROACHES. POPS INCREASE FROM 00Z TO 12Z ON SATURDAY WHICH COINCIDES WITH FAVORED ISENTROPIC ASCENT AHEAD OF THE COLD FRONT. PWAT VALUES REMAINED NEAR 3/4 OF AN INCH...WHICH IS GOOD FOR THIS TIME OF YEAR. WITH THE 12Z MODEL RUNS PUSHING THE COLD FRONT THROUGH A LITTLE FASTER...PRECIP AMOUNTS WERE LOWERED A TINY BIT. THE COLD FRONT IS EXPECTED TO EXIT THE AREA EARLY SATURDAY MORNING...BRINGING AN END TO THE HEAVIER PRECIP. SHOWERS WILL LINGER BEHIND THE FRONT BEFORE RIDGING MOVES BACK IN AND TEMPERATURES DROP BACK BELOW FREEZING. TEMPERATURES WERE DROPPED A LITTLE BIT TO TAKE INTO ACCOUNT THE SNOW COVER AND THE FASTER TIMING OF THE COLD FRONT THROUGH THE AREA SATURDAY EVENING. WAA WORKS IN AS STRONG SOUTHERLY FLOW INCREASES BEHIND THE WARM FRONT LATE FRIDAY BEFORE CAA TAKES OVER WITH THE EXITING COLD FRONT SATURDAY AFTERNOON. TEMPERATURES REMAIN ABOVE FREEZING AND STEADY FRIDAY INTO FRIDAY NIGHT BEFORE DROPPING BACK DOWN ONCE AGAIN. SURFACE RIDGING OVER THE GREAT LAKES REGION WILL KEEP SUNDAY MOSTLY DRY. SOUTHWESTERLY WINDS PICK UP ON SUNDAY WITH GUSTS UP TO 25 MPH DURING THE DAY. THERE IS SOME UNCERTAINTY AMONGST MODELS REGARDING PRECIPITATION CHANCES ON MONDAY. THEREFORE...HAVE ONLY KEPT A SLIGHT CHANCE IN THE FORECAST. HOWEVER...THERE LOOKS TO BE BETTER AGREEMENT THAT TUESDAY COULD BRING SOME PRECIP TO THE REGION. 850 MB TEMPS LOOK TO BE COLD ENOUGH TO SUPPORT ALL SNOW FOR PRECIP ON TUESDAY. HIGH TEMPERATURES WILL START OFF ABOVE NORMAL /FORECASTED HIGHS IN THE UPPER 30S/ ON MONDAY AND SLOWLY DECREASE THROUGHOUT THE REMAINDER OF THE WEEK DROPPING TO THE MID 20S BY THURSDAY. LOWS WILL ALSO START OFF ABOVE NORMAL /LOW 30S/ FOR MONDAY NIGHT AND STEADILY DROP INTO THE LOW TEENS /BELOW NORMAL/ BY THURSDAY NIGHT. && .MARINE... SOUTHERLY FLOW WILL CONTINUE TO INCREASE THROUGH TONIGHT AS HIGH PRESSURE SLIDES TOWARDS THE EAST COAST. LOW PRESSURE APPROACHING FROM THE PLAINS WILL THEN MAINTAIN SOUTHERLY FLOW THROUGH FRIDAY...WITH SPEEDS INCREASING FRIDAY NIGHT AS A WARM FRONT LIFTS UP THROUGH THE GREAT LAKES. SOUTH TO SOUTHEAST WINDS WILL BECOME GUSTY OVER LAKE HURON FRIDAY NIGHT AS THE LOW TRACKS UP THROUGH LAKE MICHIGAN. SUSTAINED SPEEDS LOOK TO RANGE BETWEEN 20 AND 28 KNOTS OVER MUCH OF THE LAKE...HOWEVER WARMER AIR FLOWING OVER THE LAKE SURFACE WILL KEEP STABILITY HIGH AND LIMIT WIND GUSTS TO BELOW GALE FORCE. COLDER AIR WILL POUR INTO THE REGION ON THE BACKSIDE OF THE SYSTEM ON SATURDAY. THE ARRIVAL OF THE COLDER AIR COMBINED WITH A TIGHT SURFACE PRESSURE GRADIENT AND STRONG WINDS ABOVE THE LAKE SURFACE MAY ALLOW GALE FORCE WINDS TO DEVELOP OVER THE CENTRAL PORTION OF LAKE HURON. A GALE WATCH IS NOW IN EFFECT OVER THE CENTRAL PORTION OF THE LAKE ON SATURDAY...INCLUDING SAGINAW BAY AND THE NEARSHORE WATERS FROM PORT AUSTIN TO HARBOR BEACH. WIND SPEEDS WILL DECREASE SATURDAY NIGHT AND SUNDAY AS HIGH PRESSURE BUILDS BRIEFLY BACK OVER THE AREA. && .AVIATION...ISSUED 1258 PM EST THU JAN 9 2014/ //DISCUSSION... A PATTERN OF SNOW WILL SPREAD OVER SE MICHIGAN AHEAD OF A WARM FRONT ORGANIZING OVER THE OHIO VALLEY. UPSTREAM OBSERVATIONS INDICATE HEAVIER SNOW SHOWERS WILL BE CAPABLE OF QUICK IFR VISIBILITY RESTRICTION BEFORE CEILING LOWERS TO IFR TOWARD SUNRISE AS WELL. THESE CONDITIONS WILL BE MORE SOLID FROM PTK SOUTHWARD DURING THE EVENING BEFORE STRATUS ASSOCIATED WITH THE WARM FRONT CATCHES UP TO ALL LOCATIONS AFTER MIDNIGHT. THE POTENTIAL FOR FREEZING DRIZZLE IS HIGHER TOWARD SUNRISE IN THE DTW TO PTK CORRIDOR CLOSER TO THE SURFACE WARM FRONT BUT IT IS POSSIBLE AS FAR NORTH AS MBS JUST WITH LOWER CONFIDENCE THERE. FOR DTW... SNOW SPREADING NORTHWARD FROM OHIO AND INDIANA WILL REACH THE TERMINAL NEAR 22Z AND LAST THROUGH THE EVENING. THERE IS POTENTIAL FOR A HEAVIER BURST OF LARGE BUT DRY FLAKES CAPABLE OF IFR RESTRICTION AND A QUICK HALF INCH OF ACCUMULATION. COVERAGE AND DURATION OF SUCH ACTIVITY REMAINS IN QUESTION FOR ANY GREATER SNOW ACCUMULATION AT THIS POINT. A FEW HOURS OF FREEZING DRIZZLE IS EXPECTED TO BEGIN TOWARD SUNRISE AND LAST THROUGH LATE MORNING WHEN TEMPERATURE IS ON SCHEDULE TO RISE ABOVE FREEZING. //DTW THRESHOLD THREATS... * HIGH CONFIDENCE IN CEILING BELOW 5000 FEET. * HIGH CONFIDENCE IN SNOW AS PRECIPITATION TYPE DURING THE EVENING. * MEDIUM CONFIDENCE IN FREEZING DRIZZLE DEVELOPMENT TOWARD SUNRISE FRIDAY. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LAKE HURON... GALE WATCH...LHZ362-LHZ363-LHZ421-LHZ422-LHZ441-LHZ462...FROM 7 AM SATURDAY TO 7 PM SATURDAY. LAKE ST CLAIR...NONE. MI WATERS OF LAKE ERIE...NONE. && $$ SHORT TERM...BT LONG TERM....SS/RK/HLO MARINE.......SS/HLO AVIATION.....BT YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
640 PM CST FRI JAN 10 2014 .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 255 PM CST FRI JAN 10 2014 BEGINNING TO LOOK LIKE FZDZ MIGHT BE ABOUT ALL THE MPX AREA SEES FROM THE UPPER WAVES WORKING ACROSS THE CENTRAL CONUS NOW. THE PROBLEM CONTINUES TO BE A DELAYED PHASING OF A NORTHERN STREAM WAVE CURRENTLY HEADING FOR NW MN AND A SRN STREAM WAVE THAT IS MOVING UP OUT OF IA TOWARD WI. THESE TWO SYSTEMS DO NOT REALLY LOOK TO BECOME ONE UNTIL SAT MORNING OVER MICH. THE RUB THERE IS THAT THE SRN STREAM WAVE IS THE ONE WITH ALL OF THE MOISTURE AND THEREFORE PRECIPITATION AND WITH THESE SYSTEMS NOT PHASING UNTIL SATURDAY...WE ARE SEEING THE PRECIPITATION MOVING THROUGH FASTER AND FARTHER EAST TODAY/TONIGHT. RUNS OF THE HOPWRF TODAY HAVE BEEN PROGRESSIVELY INCHING A DEFORMATION BAND EAST WITH TIME AND WITH THE 15Z RUN ALL 4 MEMBERS ARE NOW SHOWING A BAND OF ENHANCED PRECIP FALLING FROM ABOUT DECORAH...IA UP TOWARD WAUSAU...EAST OF THE MPX CWA. ON RADAR...THERE IS A CLUSTER OF HIGHER RETURNS THAT MATCHES UP WELL WITH THESE PRECIPITATION SWATHS AND WITH THE HRRR PICKING UP ON THIS SCENARIO NOW AS WELL...CONFIDENCE IS BEGINNING TO INCREASE THAT THIS SYSTEM WILL BE A DUD IN THE SNOWFALL DEPARTMENT FOR THE MPX AREA. WITH ALL OF THAT SAID...STILL ANTICIPATE SOME LIGHT SNOW TO DEVELOP MAINLY EAST OF THE I-35 CORRIDOR AS THE SFC TROUGH THAT IS STILL HANGING OUT ALONG THE MN/DAKOTAS BORDER SLIDES EAST THIS EVENING...MEETING UP WITH THE DEEPER MOISTURE STREAMING NORTH INTO WI. HAVE FOLLOWED THE IDEA OF THE HRRR AND OTHER HI-RES MODELS WHICH SHOW JUST LIGHT QPF/SIMULATED REFLECTIVITY DEVELOPING OVER ERN MN WITHIN THE NEXT COUPLE OF HOURS BEFORE SLOWLY SLIDING EAST. SAID SFC TROUGH WILL CLEAR THE MPX AREA AROUND 9Z...WITH ANY SNOW LIKELY CUTTING OFF AFTER THAT. BASICALLY...THERE MIGHT BE ONE OR TWO LUCKY FOLKS OUT THERE THAT PICK UP A HALF INCH OF SNOW OUT OF THIS...OTHERWISE IT IS JUST A SEA OF LOW CLOUDS AND HAZE UNTIL THE SFC TROUGH CLEARS AND WINDS BECOME WNW. AS FOR TONIGHT...FOLLOWED THE IDEA OF THE RAP AND NAM OF SKIES SCATTERING OUT AT LEAST FOR A LITTLE WHILE AS BOUNDARY LAYER WINDS BECOME MORE WRLY...MUCH LIKE WHAT HAS BEEN SEEN TODAY ACROSS THE DAKOTAS. THINKING WE WOULD SEE SOME CLEARING...DID FOLLOW THE IDEA MOST GUIDANCE SHOWS OF KNOCKING LOWS BACK INTO THE LOWER TEENS FOR MUCH OF THE AREA WEST OF TWIN CITIES. NOT MUCH TO SAY ABOUT SATURDAY...OTHER CLOUDS CURRENTLY MOVING INTO NRN NODAK SWEEP THROUGH HERE DURING THE MORNING/EARLY AFTERNOON WITH HIGHS STILL LOOKING TO NESTLE UP INTO THE 5-10 DEGREES ABOVE NORMAL RANGE. SO MADE ONLY MINOR CHANGES TO EXISTING FORECAST...MAINLY JUST BLENDING IN LATEST BIAS CORRECTED MODEL DATA. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 255 PM CST FRI JAN 10 2014 LONGER TERM TRENDS CONTINUE TO INDICATE RATHER PROGRESSIVE UPPER LEVEL FLOW PATTERN OVER THE AREA DURING THE PERIOD. COOLING TREND APPEARS TO TAKE HOLD BY LATE IN THE PERIOD AS ANOTHER AREA OF COLD AIR DIVES SOUTHEAST ALONG THE AMPLIFYING HUDSON BAY VORTEX. A LIGHT MIX OF PRECIPITATION MAY STILL OCCUR UNDER STRONG WAA PATTERN UNDER STRONG 130KT H25 JET SUNDAY INTO SUNDAY NIGHT. WARMING ALOFT INDICATES FAVORABLE THICKNESS FOR POSSIBLE LIGHT ZR-/ZL- INTO THE DAY AS SURFACE TEMPERATURES WARM THROUGH THE LOWER 30S DURING TH DAY. WHATEVER IS LEFT INTO THE EVENING/SUNDAY OVERNIGHT WILL CHANGE OVER TO SNOW...BUT ONLY LIGHT QPF AMOUNTS ARE INDICATED. DETERMINISTIC EC AND GFS CONTINUE TO SHOW ANOTHER WEAK CLIPPER TYPE SYSTEM DIVING SOUTHEAST ALONG WEAK SURFACE BOUNDARY... AFFECTING MAINLY SOUTHERN CWA DURING THE MONDAY INTO MONDAY NIGHT PERIOD. TIMING IS IN QUESTION...WITH THE 12Z GFS A BIT FASTER THAN THE 12Z EC. WONT GET TOO CUTE ON TIMING OF THIS SYSTEM NOW...BUT WE COULD SEE SOME LIGHT SNOW ACCUMULATION WITH THIS AS IT PASSES THROUGH. BRIEF SHOT OF COLDER AIR ARRIVES FOR TUESDAY/TUESDAY NIGHT AHEAD OF NEXT SURGE OF PACIFIC AIR FOR WEDNESDAY. MODELS INDICATE THE NEXT MAIN SURGE OF ARCTIC AIR ARRIVES THURSDAY AND WILL LINGER THROUGH THE END OF THE PERIOD AS THE EASTERN CONUS TROUGH DIGS SOUTHEAST. AT THE MOMENT...IT DOESNT APPEAR TO BE AS COLD AS THE LAST WILL HAVE TO MONITOR DEVELOPMENT OF THE TROUGH INTO NEXT WEEK. COULD SEE SOME LIGHT SNOW/SNOW SHOWERS WITH THIS AS IT DIVES SOUTHEAST AND THE COLD AIR ARRIVES. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING) ISSUED AT 547 PM CST FRI JAN 10 2014 VERY TRICKY FORECAST THIS TAF PERIOD...ESPECIALLY WITH RESPECT TO CEILINGS FOR ALL SITES AND P-TYPES FOR THE WI SITES. SFC TROUGH SWINGING THRU WRN MN AT INITIALIZATION TIME IS ALLOWING FOR CLEARING SKIES IN WRN MN...WHILE IFR-AND-LOWER CONDS WITH BR/FG/FZFG AND EVEN SOME PATCHY -FZDZ LIES AHEAD OF SAID TROUGH AND IS AFFECTING ALL TAF SITES. IN THE CLEARING...WINDS HAVE SWUNG TO WLY...SO IT IS DIFFICULT TO GO WITH LAMP GUIDANCE WHICH KEEPS IN THE IFR CONDS DESPITE THE WIND SHIFT WHICH WOULD INHIBIT MOISTURE ADVECTION INTO THE AREA. THEREFORE...HAVE MAINTAINED SIMILAR THINKING TO THE 18Z TAFS BY TIMING IN THE WLY WIND SHIFT ALONG WITH CONDS GOING TO VFR GRADUALLY FROM W TO E THIS EVE THRU THE OVERNIGHT HRS. LOWER CLOUDS FILL BACK IN DURG THE DAY TMRW AS MOISTURE/SUBSIDENCE BEHIND THE DEPARTING TROF SWING THRU THE AREA. HOWEVER...WITH THIS SECOND BATCH...AM NOT THINKING CIGS WILL DROP INTO MVFR SO HAVE HELD CLOUDS IN LOWER-RANGE VFR ATTM. AS FOR PRECIP...ONLY KEAU IS LIKELY TO SEE PRECIP THRU THIS EVENING /AND POSSIBLY KRNH/ AND WILL LIKELY BE -FZDZ RATHER THAN -SN SINCE THE DEEPER MOISTURE AND BETTER CRYSTAL GROWTH AREAS WILL BE WELL S AND E OF KEAU. PRECIP WILL BE MAINLY THIS EVE INTO THE EARLY MRNG HRS. KMSP...IFR CONDS TO PERSIST THRU THIS EVE INTO THE EARLY MRNG HRS...POSSIBLY EVEN WITH CEILINGS DROPPING INTO LIFR LEVELS FOR SOME HOURS...BUT AM ANTICIPATING A BINOVC AND WILL LOOK FOR VFR CONDS TO PREVAIL SHORTLY BEFORE SUNRISE. WITH THE SWITCH TO W WINDS...MODELS ARE HIGHLY OVERDOING THE COVERAGE OF IFR CIGS SO TIMING THE LARGE BREAK OVER WRN MN AND ERN ND WILL PUT VFR CONDS IN THE MSP AREA BY 10Z. VFR CONDS THEN LOOK TO HOLD ON THRU MIDDAY BEFORE LOWER-END VFR CIGS RETURN ON THE BACKSIDE OF THE DEPARTING UPR LVL TROF. AM NOT EXPECTING PRECIP INTO MSP OTHER THAN BR AND POSSIBLY VERY LIGHT -FZDZ FOR THIS EVENING. /OUTLOOK FOR KMSP/ SUN...VFR. WINDS SW 10-15 KTS. MON...VFR. CHC MVFR/-SN OVERNIGHT. WINDS W-SW 5-10 KTS. TUE...VFR. CHC MVFR CIGS. WINDS NW 15G25 KTS. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. && $$ SHORT TERM...MPG LONG TERM...DWE AVIATION...JPC
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON MS
1106 AM CST THU JAN 9 2014 .UPDATE... SATELLITE IMAGERY SHOWS EXTENSIVE CLOUD DECK OVER THE NWRN AREAS FROM LIFT FROM APPROACHING WEAK S/WV IN THE NW DELTA. ALSO IN THIS REGION A STALLED FRONTAL BOUNDARY IS DRAPED THROUGH THE ARKLAMISS DELTA. SOME LIGHT FREEZING RAIN IS OCCURRING JUST ALONG/SLIGHTLY IN THE FAR NW DELTA IN CHICOT COUNTY. ADDED CHANCE OF LIGHT FREEZING RAIN IN FAR NRN ASHLEY/CHICOT/BOLIVAR COUNTIES UNTIL 20Z. THIS REGION SHOULD WARM UP ENOUGH IN THE NEXT FEW HOURS TO BE JUST CHANCES FOR SHOWERS. SOME DECENT ISENTROPIC LIFT/MOISTURE ADVECTION IS AIDING IN SHOWERS MOVING THROUGH THE DELTA REGION. GLOBAL/HI-RES MODELS...SUCH AS THE HRRR AND HWRF...KEEP MOST OF THE ACTIVITY IN THE DELTA TODAY. OVERALL...CURRENT POPS LOOK GOOD FOR TODAY. HAD TO INCREASE QPF IN THE NW SLIGHTLY. TEMPERATURES ARE REBOUNDING FAIRLY QUICKLY IN THE WAKE OF THE EASTWARD BUILDING SURFACE HIGH. SOME OF THE CLOUDS WERE CLEARING SOMEWHAT ALONG/SE OF A LINE FROM NATCHEZ TO COLUMBUS. AREAS IN THE E SHOULD BE MODERATING SLIGHTLY WHILE WARMER TEMPS IN THE W/SW ARE POSSIBLE AS TEMPS ALOFT CONTINUE TO INCREASE. WENT CLOSE TO MAV HIGHS FOR TODAY...SLIGHTLY LOWERING TEMPS IN THE NW DUE TO RAIN/CLOUDS AND INCREASING HIGHS IN THE CENTRAL/SW DUE TO SOME DECREASING CLOUDS. /DC/ && .AVIATION...MOSTLY VFR CONDITIONS ARE OCCURRING ACROSS A GOOD PORTION OF THE AREA THIS MORNING DESPITE A SCT-BKN CLOUD DECK. THE EXCEPTION TO THIS IS IN THE DELTA WHERE MVFR CONDITIONS ARE AFFECTING MOSTLY KGLH. -RA WILL CONTINUE TO AFFECT THIS REGION TODAY AND THIS SHOULD RESULT IN CONTINUED MVFR CEILINGS. ELSEWHERE...VFR CONDITIONS WILL CONTINUE THROUGH THE AFTERNOON. /28/ && .PREV DISCUSSION... /ISSUED 356 AM CST THU JAN 9 2014/ SHORT TERM...TODAY THROUGH FRIDAY NIGHT. THE PRIMARY CONCERNS WILL BE THE CHANCE OF SHOWERS AND EMBEDDED THUNDERSTORMS FOR FRIDAY AND FRIDAY NIGHT...FOLLOWED BY CHANCE OF SHOWERS MAINLY IN THE DELTA FOR TODAY THROUGH TONIGHT. THIS FOLLOWED BY TEMPS AND POPS. LATEST SATELLITE IMAGERY SHOWED THE REGION UNDER SOUTHWEST FLOW WITH A WEAK SHORTWAVE APPROACHING FROM THE PLAINS. A STATIONARY FRONTAL BOUNDARY EXTENDED FROM SOUTHEAST ARKANSAS WESTWARD. THIS WAS SEPARATING THE COOLER AIR ACROSS THE OZARKS WITH THE FREEZING PRECIPITATION AND THE MORE MODERATE AIR WITH SHOWERS TO THE SOUTH. THE COMBINATION OF LOW TO MID LEVEL CLOUDS AND LOW LEVEL SOUTHERLY ADVECTION HAVE IMPEDED THE COOLING ACROSS THE DELTA REGION THIS MORNING...AS TEMPERATURES HAVE BEEN HOLDING STEADY FROM 35 TO AROUND 40 DEGREES. AREA RADARS WERE PICKING UP LIGHT SHOWERS PUSHING NORTHEAST ACROSS THE DELTA REGION. FOR TODAY AND TONIGHT THE LOCAL WRF...HRR AND NATIONAL WRF MODELS KEEP THE LIGHT SHOWERS ACROSS THE DELTA REGION. HIGHS TODAY WILL BE FROM THE LOWER 40S NORTHWEST TO THE UPPER 50S SOUTHEAST. WENT CLOSE TO GMOS GUIDANCE. ON POPS ADJUSTED THE BETTER NAM POPS. THE GMOS AND MAV POPS WERE TOO FAR SOUTHEAST IN COMPARISON TO LOCAL AND NATIONAL WRF RUNS. FOR TONIGHT LOWS WILL BE FROM THE UPPER 30S EAST HALF TO THE MIDDLE 40S SOUTHWEST. WENT CLOSER TO THE MILDER NAM GUIDANCE WITH THE CLOUD COVER. FOR POPS LOCAL AND NATIONAL WRF KEEPS THE SHOWERS ACROSS THE DELTA REGION...BUT MODEL POPS LOOK TO HAVE TOO MUCH POP COVERAGE. SO OPTED TO KEEP THE CURRENT FORECAST POPS FOR MAINLY THE DELTA REGION. FOR FRIDAY AND FRIDAY NIGHT...THINGS START TO PICK UP SOME FROM THE WEST. A SHARP SOUTHERN SHORTWAVE PIVOTS TOWARD THE REGION FROM THE SOUTHERN PLAINS. THE GFS WAS THE FASTEST WITH THE TRACK. OPTED TO GO WITH THE SLOWER TRACK OF THE OTHER MODELS. LIGHT SHOWERS WILL BE ACROSS THE WEST ON FRIDAY MORNING...BUT MODERATE SHOWERS WILL SPREAD ACROSS THE REGION DURING THE AFTERNOON AS PWATS WILL INCREASE TO AROUND 1.3 INCHES. INSTABILITY WILL INCREASE IN THE FAR WEST DURING FRIDAY AFTERNOON FOR SOME ISOLATED THUNDER. INSTABILITY WILL GRADUALLY BUILD AND SPREAD ACROSS THE REGION FOR FRIDAY NIGHT AS SCATTERED EMBEDDED THUNDERSTORMS WILL DEVELOP ACROSS THE REGION. SPC HAS A 5 PERCENT RISK ACROSS THE FAR SOUTH DUE TO BETTER INSTABILITY AND SOME SHEAR. DO NOT BELIEVE THAT IT WARRANTS ANY MENTIONING IN THE HWO. AFTER MIDNIGHT THE RAINS WILL START TO DECREASE FROM THE WEST AS THE COLD FRONT CROSSES THE REGION. THIS WILL BE ENDING THE EMBEDDED THUNDER FROM THE WEST. LOW LEVEL WARM ADVECTION WILL BRING HIGHS FROM THE UPPER 50S NORTH TO THE MIDDLE 60S SOUTHWEST...WHICH IS CLOSE TO MAV GUIDANCE. THIS WILL BRING SOME ABOVE NORMAL READINGS ACROSS THE REGION. LOWS FOR FRIDAY NIGHT WILL BE FROM THE MIDDLE 40S NORTHWEST TO THE UPPER 50S SOUTHEAST. ABOVE NORMAL LOWS WILL BE AROUND 10 TO 20 DEGREES ABOVE NORMAL. WENT CLOSE TO THE NAM GUIDANCE FOR POPS AND TEMPS. /17/ LONG TERM...SATURDAY THROUGH THURSDAY...A COLD FRONT WILL CONTINUE TO WORK ITS WAY ACROSS THE AREA SATURDAY. THE ECMWF/CANADIAN/NAM ARE SLOWER WITH THE BOUNDARY ON SATURDAY THAN THE GFS...SO HAVE BUMPED UP POPS FOR AREAS EAST OF I-55 DURING THE LATE MORNING INTO THE EARLY AFTERNOON HOURS.. EXPECT A FEW LINGERING SHOWERS IN THE EAST SATURDAY AFTERNOON BEFORE SURFACE RIDGING AND DRIER AIR BUILD OVER THE AREA SATURDAY NIGHT INTO SUNDAY. A NICE DAY IS ON TAP FOR SUNDAY AS A SURFACE HIGH MOVES ACROSS THE SOUTHERN PORTIONS OF THE AREA AND HIGH TEMPS CLIMB INTO THE MID 60S. THE SURFACE FLOW WILL BECOME MORE SOUTHERLY ONCE AGAIN ON MONDAY WITH HIGH PRESSURE SHIFTING TO THE EAST. THE ECMWF AND GFS ARE PRETTY CLOSE ON THE TIMING OF AN UPPER TROUGH MOVING ACROSS THE AREA ON MONDAY...BUT THE ECMWF IS MUCH DEEPER WITH THE TROUGH AND ALSO DEVELOPS A SURFACE LOW THAT MOVES FROM THE NORTHERN GULF ALONG THE SURFACE BOUNDARY ACROSS THE AREA MONDAY AFTERNOON. THE ECMWF HAS DONE A MUCH BETTER JOB WITH THE DEVELOPMENT OF THESE SYSTEMS THIS WINTER SO FAR...SO WILL LEAN TOWARDS IT AND BUMP POPS UP ON MONDAY ACROSS THE AREA. THE TEMPS WILL BE WARM ENOUGH FOR THE PRECIP TO REMAIN ALL RAIN ON MONDAY BEFORE ENDING MONDAY EVENING. ANOTHER COLD FRONT WILL DROP SOUTH ACROSS THE AREA TUESDAY AFTERNOON...USHERING IN COLDER AIR. THE ECMWF IS DEEPER WITH THE UPPER TROUGH LATE IN THE PERIOD AND THIS WOULD INDICATE COOLER TEMPS IN THE EXTENDED...SO WILL BUMP TEMPS DOWN A BIT BELOW MEX GUIDANCE WEDNESDAY AND THURSDAY. BOTH DAYS LOOK MAINLY DRY/COOL AS HIGH PRESSURE RIDGING PREVAILS. /15/ && .PRELIMINARY POINT TEMPS/POPS... JACKSON 54 39 61 55 / 12 11 24 100 MERIDIAN 56 39 60 57 / 6 10 19 100 VICKSBURG 55 41 64 56 / 33 19 28 100 HATTIESBURG 60 38 62 57 / 6 10 18 100 NATCHEZ 56 47 64 56 / 13 12 28 100 GREENVILLE 42 40 60 50 / 82 26 30 100 GREENWOOD 46 41 62 55 / 49 23 28 100 && .JAN WATCHES/WARNINGS/ADVISORIES... MS...NONE. LA...NONE. AR...NONE. && $$ DC/28/17/15
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
949 PM CST Fri Jan 10 2014 .UPDATE: Issued at 945 PM CST Fri Jan 10 2014 The new swath of rain with the warm conveyor was centered from just west of Litchfield through the St. Louis metro into southeast MO. It is moving rather quickly to the northeast and should exit much if not all of MO before midnight as the progressive upstream trof continues to advance east and dry air moves in aloft. Adjustments this evening were just temporal trends with the rain and temperatures. During the overnight period and more specifically after 09z I increased the pops through central and northeast MO. There is a growing area of rain and snow across eastern KS due to what appears to be a mid-upper level deformation zone. The RAP and HRRR rotate this precipitation into the aforementioned area after 09z and weaken it by 12z. My pops while higher than the previous forecast may not be high enough if it maintains more identity. Glass && .SHORT TERM: (Through Tonight) Issued at 1217 PM CST Fri Jan 10 2014 Focus will be precip tonight, but in two areas. First, the ongoing RA that will be moving out of the region late tonight. The second, is precip associated with the upper trof currently over the Plains. Believe ongoing precip will be confined to the ern half of the CWA at the beginning of the period. Precip shud continue pushing quickly ewd and only be in the far ern counties by Midnight. Not much change in the way of QPF thru tonight. The other area of precip may be across nrn portions of the CWA late tonight as the upper trof moves thru. Mdls are in fairly good agreement with timing/placement of this feature. However, mdls suggest a lack of available moisture will prevent any precip by the time the trof reaches the CWA. POPs or mention of flurries may need to be added to these areas late tonight. As for temps, expect temps to remain steady or even rise ahead of the cdfnt as it moves thru the area. Resultant temps are around the warmer guidance as airmass behind the fnt is not that cold based on upstream obs. Tilly .LONG TERM: (Saturday through Next Friday) Issued at 251 PM CST Fri Jan 10 2014 (Saturday through Monday) After further critique of the latest guidance for Sat, have decided to add slight chance for SN continuing into the early morning hours. There is still a lot of uncertainty if enuf moisture will remain to produce SN, but believe it is worthy of slight chances. If the SN does occur, with the relatively warm bndy temps, do not anticipate much in the way of accumulations. Next system reaches the region on Sun night into Mon as another deep trof approaches the region. For now, have kept POPs in the low chance range due to a fair amount of uncertainty among guidance regarding strength and placement of the trof and sfc reflection. Continued trend twd warm temps with upper ridging moving into the region. (Tuesday through Friday) Period begins with a focus on precip chances on Tues as a clipper approaches the area. Each mdl has a different soln with vast differences between them. Given the system is a clipper, will likely have low confidence in any given soln until much closer to Tues. For now, will just add slight chances for SN and refine the fcst as time approaches. As for temps, have tried to trend twd a compromise of guidance. Have low confidence in any single soln as area remains under meridional flow, producing warming and cooling periods. Tilly && .AVIATION: (For the 00z TAFs through 00z Saturday Evening) Issued at 540 PM CST Fri Jan 10 2014 Rain has ended at KCOU/KUIN, but a stray shower or thunderstorm is still possible at KCOU until 05-07z depending on the evolution of SHRA/TSRA occurring over southwestern MO. This potential will be closely monitored over the next few hours. Although a few sites were reporting VFR conditions at TAF issuance time, this is likely to be short lived based on surrounding IFR obs and prevailing flow. Winds will become westerly with the passage of a cold front later tonight, and the arrival of drier air on Saturday combined with mixing will cause IFR/MVFR cigs to dissipate. Beyond the end of the valid TAF period, fog and/or stratus is expected to redevelop on Saturday night due to the moist ground. For KSUS/KCPS, please see the section for KSTL below. Specifics for KSTL: Although VFR conditions were reported at TAF issuance time, such conditions are likely to be short lived based on surrounding IFR obs and prevailing flow. Rain will continue on and off for a few more hours before ending, and there is also a chance that the thunderstorms developing over eastern OK and southwestern MO may spread northeastward towards KSTL. This potential will be closely monitored over the next few hours. Measurable precipitation then ends with the passage of a cold front between 06-08z. Drier air will lead to improving cigs, especially after 12-15z. Beyond the end of the TAF period, fog and/or stratus is expected to redevelop on Saturday night due to the moist ground. Kanofsky && .LSX WATCHES/WARNINGS/ADVISORIES: MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS BILLINGS MT
328 PM MST THU JAN 9 2014 .SHORT TERM...VALID FOR FRI AND SAT... MAIN FORECAST ISSUE REMAINS WIND. SHORTWAVE MOVING THROUGH THE REGION IS PRODUCING SOME RAIN/SNOW SHOWERS...MAINLY OVER OUR MTNS SO FAR...AND WITH MID LEVEL FLOW TURNING NW WE ARE SEEING SOME ECHOES FORM SE OF BILLINGS...AS WAS EXPECTED. STRONGEST ASCENT IS PUSHING WELL TO OUR SOUTH SO PCPN WILL BE GENERALLY LIGHT INTO THE EVENING...WITH MAYBE A COUPLE INCHES OF SNOW OVER THE BIG HORNS. FISHER CK SNOTEL ABOVE COOKE CITY PICKED UP 6 INCHES OF SNOW EARLIER TODAY. ATTENTION TURNS QUICKLY TO INCREASING PACIFIC JET AND ENERGY ALONG THE BC COAST. LEE SIDE PRESSURE FALLS SHOULD COMMENCE BY LATE EVENING AND OUR NEXT LIVINGSTON...BIG TIMBER...BEARTOOTH FOOTHILLS WIND EVENT WILL MATERIALIZE AS THE NIGHT WEARS ON. THIS WILL BE A MORE DYNAMIC EVENT WITH FASTER MID LEVEL FLOW...SO SHOULD BE A SOLID WIND ADVISORY WITH GUSTS OF 60-65 MPH LATE TONIGHT AND FRIDAY. CORE OF STRONGEST MID LEVEL FLOW...60 KTS PER THE GFS AND 70 KTS PER THE NAM...WILL PUSH INTO THE CRAZY MTN/WHEATLAND COUNTY AREA 12-18Z TOMORROW. LATEST RAP IS CONSISTENT WITH THESE SPEEDS AT 14Z TOMORROW. SUBSIDENCE FROM PAC SHORTWAVE WILL BE THE MECHANISM TO ALLOW STRONGER WINDS TO SFC...SO FEEL WE SHOULD SEE GUSTS OF 50-60 MPH FROM MELVILLE TO HARLOWTON TO A LITTLE SOUTH OF JUDITH GAP DURING THE DAY TOMORROW...THOUGH SFC AND MID LEVEL WINDS WILL NOT BE PERFECTLY LINKED UP. WILL ISSUE A HIGH WIND WARNING TO COVER THESE AREAS. SHOULD BE AT LEAST A MODEST DECREASE IN THE WIND BY FRIDAY NIGHT BEHIND PRESSURE RISES AND AS NEXT GAP EVENT GETS WARMED UP. FURTHER EAST ON FRIDAY...INCREASED MIXING WITH UP TO 40-45 KTS OF 850MB FLOW SHOULD YIELD STRONG GUSTS AS FAR EAST AS BILLINGS BY LATE MORNING...WHERE SFC GUSTS WILL REACH 40-50 MPH. AN OVERALL WINDY DAY ACROSS THE REGION TOMORROW. NEXT PERIOD OF STRONG WINDS BEGINS EARLY SATURDAY AND WILL KEEP HIGH WIND WATCHES INTACT ACROSS OUR WEST FROM SAT-MON. WITH 700MB WINDS TO 80 KTS AND A TIGHTER SFC GRADIENT THERE SHOULD BE 70+ MPH GUSTS AT THE GAP LOCATIONS...WITH A BIT LESS ELSEWHERE ACROSS OUR WEST. HAVE ATTEMPTED TO FIND A TIME WHEN MOUNTAIN WAVE ACTIVITY COULD BE A THREAT...AND THINK SATURDAY IS A RISK. NAM MAY BE A BIT OVERDONE BUT SHOWS A REGION OF NEAR 90 KT OF MTN TOP WIND ALONG THE BEARTOOTH FRONT BY 18Z SATURDAY. GFS IS A BIT WEAKER AND LATER WITH THE WIND POTENTIAL...BUT BOTH MODELS SUGGEST A MID LEVEL SHORTWAVE AND POTENTIAL FOR ENHANCED DOWNWARD MOTION IN THE LEE OF THE MTNS SOMETIME IN THE MIDDAY TO EVENING TIME PERIOD ON SATURDAY...WITH THE PREFRONTAL HOURS BEING MOST FAVORED FOR THIS TO OCCUR. COLD ADVECTION AND DESTABILIZING WILL REDUCE THE MTN WAVE THREAT LATER IN THE DAY ON SATURDAY. HAVE OPTED TO ISSUE A HIGH WIND WATCH FOR THE RED LODGE FOOTHILLS TO COVER THIS. NO DOUBT THE WINDS WILL BE SCREAMING ON THE MOUNTAINS ABOVE RED LODGE...SO OUTDOOR RECREATIONISTS TAKE NOTE. OTHERWISE...MOIST PACIFIC FLOW WILL BRING ADDITIONAL PERIODS OF OROGRAPHIC SNOWFALL TO THE WEST SLOPES OF THE BEARTOOTH ABSAROKAS THROUGH SATURDAY NIGHT...WITH A STEEPENING OF LAPSE RATES LATE SAT AND SAT NIGHT BEING THE EXPECTED TIME PERIOD OF HEAVIEST SNOWFALL. WILL KEEP POPS HIGH AND SNOW AMOUNTS SPREAD OVER THE NEXT FEW PERIODS. ACCUMS SHOULD ADD UP TO EXCEED A FOOT OVER THE NEXT 2-3 DAYS. TEMPS WILL REMAIN MILD OVER THE NEXT COUPLE DAYS. WARMEST AIRMASS WILL EXIST ON SATURDAY WITH MODELS SHOWING 850MB TEMPS TO AROUND +10C WITHIN THERMAL SFC TROF. WIND SHIFT MAY OCCUR TOO LATE FOR BILLINGS TO MAXIMIZE ITS TEMPERATURE POTENTIAL ON SATURDAY...PER USUAL INFLUENCE FROM THE CLARKS FORK/SW WINDS...BUT IF WINDS DO SHIFT WESTERLY BEFORE 00Z WE COULD SEE TEMPS INTO THE 50S. SNOW COVER WILL ALSO BE A FACTOR. AS IT STANDS...FEEL SOME AREAS WILL SEE 50+ DEGREE HIGHS. JKL .LONG TERM...VALID FOR SUN...MON...TUE...WED...THU... PROGRESSIVE NORTHWESTERLY FLOW WILL PREVAIL IN THE EXTENDED FORECAST...PRODUCING PERIODS OF STRONG WINDS ACROSS THE AREA. PICKING UP ON SUNDAY...SHORTWAVE OVERHEAD WILL PUSH EAST DURING THE DAY AND SURFACE HIGH WILL SKIM ACROSS EASTERN MONTANA. TEMPERATURES WILL BE COOLER BEHIND THE COLD FRONT ON SUNDAY...ESPECIALLY FOR EASTERN COUNTIES. SUNDAY WILL ALSO BE WINDY ACROSS THE AREA WITH COLD ADVECTION AND SUBSIDENCE HELPING TO PUSH 45 TO 50 KTS OF 850 HPA AND 700 HPA WIND TOWARD THE SURFACE. A STRONG PACIFIC JET STREAK MOVES INTO THE FORECAST AREA ON MONDAY...ACCOMPANYING THIS SYSTEM ARE VERY STRONG 850 AND 700 HPA WINDS. MODEL RUNS REMAIN CONSISTENT WITH 60 TO 90 KNOTS OF WIND CONCENTRATED AROUND 850MB MOVING ACROSS THE AREA THROUGH MONDAY AFTERNOON. WITH THIS MAGNITUDE OF WIND...EXPECT A STRONG MIXED WIND EVENT FOR LIVINGSTON...BIG TIMBER AND UP TO HARLOWTON. WINDS WILL ALSO BE STRONG ALL ACROSS THE PLAINS...AND WILL CONTINUE TO MONITOR THE TRENDS FOR ANY POTENTIAL WIND HIGHLIGHTS THAT MIGHT BE NEEDED FOR THIS PERIOD. MODELS HAVE ALSO BEEN CONSISTENT WITH DEVELOPING A BAND OF FRONTOGENESIS ACROSS EASTERN MONTANA WHICH WOULD RESULT IN SOME LIGHT SNOWFALL THERE. HAVE INCREASED POPS SLIGHTLY ACROSS EASTERN MONTANA TO ADDRESS THIS CONCERN. MODELS WANT TO KEEP PLENTY OF WIND AROUND ON TUESDAY...ALTHOUGH A MORE MODEST 50 KTS OR SO AT 850 MB. THUS THE WINDY PERIOD WILL CONTINUE ACROSS THE AREA...ALTHOUGH NOT QUITE AS WINDY AS MONDAY MAY BE. TEMPERATURES WILL BE MILD THROUGH THIS PERIOD AS DOWNSLOPE WINDS WILL KEEP TEMPERATURES ABOVE SEASONAL VALUES. MOUNTAIN SNOW WILL CONTINUE SUNDAY THROUGH TUESDAY AS MOIST PACIFIC FLOW CONTINUES. HOWEVER...THE MOIST FLOW MAY START TO SUBSIDE BY MIDWEEK...ENDING THE CHANCE OF SNOW SHOWERS THERE. CHURCH && .AVIATION... VFR CONDITIONS ARE EXPECTED TO PREVAIL OVERNIGHT AND EARLY FRIDAY. WINDS WILL INCREASE OVERNIGHT NEAR KLVM AND IN THE NEARBY FOOTHILLS...WITH GUSTS 50 TO 55 KTS POSSIBLE BY EARLY FRIDAY MORNING. CHURCH && .PRELIMINARY POINT TEMP/POPS... FRI SAT SUN MON TUE WED THU ----------------------------------------------------------- BIL 029/042 030/048 034/043 034/046 032/044 029/044 027/038 12/J 11/N 21/N 02/W 31/N 11/N 12/W LVM 031/040 033/049 032/040 034/043 031/043 029/042 030/034 23/W 22/W 32/W 22/W 21/N 11/N 22/W HDN 018/040 021/047 027/040 028/042 028/039 024/041 020/033 32/W 12/J 22/W 13/W 31/N 11/N 12/J MLS 019/036 020/040 028/035 025/038 023/036 022/038 019/032 22/J 12/W 32/J 14/J 32/J 11/N 12/J 4BQ 020/038 020/045 029/036 026/041 026/038 022/042 021/032 53/J 11/B 32/J 14/J 32/J 11/N 11/N BHK 021/037 020/040 029/032 021/038 023/035 018/039 019/031 22/J 11/B 32/J 13/J 22/J 11/N 11/N SHR 017/041 021/048 027/038 023/041 025/042 021/044 020/034 52/W 00/N 23/W 12/J 31/N 11/U 12/J && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...HIGH WIND WARNING IN EFFECT FROM 5 AM FRIDAY TO MIDNIGHT MST FRIDAY NIGHT FOR ZONES 28-63. HIGH WIND WATCH IN EFFECT FROM LATE FRIDAY NIGHT THROUGH MONDAY AFTERNOON FOR ZONES 28-41-63-65-66. WIND ADVISORY IN EFFECT FROM 9 PM THIS EVENING TO MIDNIGHT MST FRIDAY NIGHT FOR ZONES 41-65-66. HIGH WIND WATCH IN EFFECT FROM SATURDAY MORNING THROUGH SATURDAY EVENING FOR ZONE 56. WY...NONE. && $$ WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS HASTINGS NE
310 PM CST THU JAN 9 2014 .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 306 PM CST THU JAN 9 2014 FOCUS IS ON POTENTIAL FOR LIGHT PRECIPITATION AS A SHORTWAVE TROUGH CROSSES THE CENTRAL PLAINS. WATER VAPOR IMAGERY INDICATED A PROGRESSIVE PATTERN IN THE WESTERLIES WITH A SHORTWAVE TROUGH DIGGING OVER THE ROCKIES EARLY THIS AFTERNOON. STRATUS AND SNOW COVER HAS IMPACTED TEMPERATURES TODAY...WITH THE STRATUS SLOW TO ERODE ACROSS OUR NORTHWEST ZONES...WHILE A NEW AREA OF STRATUS IS ADVECTING NORTHWARD THROUGH KS EARLY THIS AFTN. TEMPS HAVE MANAGED TO REACH THE MID 20S TO THE MID 30S SO FAR WITH A FEW MORE HOURS OF INSOLATION LEFT. FOR TONIGHT...SOUTHERLY LLVL FLOW INCREASES AHEAD OF THE TROUGH EMERGING ONTO THE HIGH PLAINS. STRATUS WILL CONTINUE TO ADVECT TO THE NORTH AND EAST AND SIMILAR TO THIS MORNING WE ARE LOOKING AT THE POTENTIAL FOR FOG DEVELOPMENT. WINDS LOOK TO REMAIN STEADY ENOUGH TO LIMIT DENSE FOG POTENTIAL BUT WILL NEED TO MONITOR AS THE RAP AND HRRR INDICATE SOME LOCATIONS COULD SEE DENSE FOG. AHEAD OF THE APPROACHING TROUGH...ISENTROPIC LIFT INCREASES AS INDICATED ON THE 295K SURFACE...PRIMARILY ORIENTED ACROSS OUR SOUTHEAST ZONES AND THE LIFT OVER THE LLVL MOISTURE COULD LEAD TO FREEZING DRIZZLE TOWARD MORNING AND THIS REMAINS IN THE FORECAST. ALSO ACROSS OUR WESTERN ZONES...HAVE INTRODUCED LOW POPS TOWARD DAYBREAK FRIDAY AS THE MID LEVEL TROUGH REACHES THIS AREA AND FORECAST SOUNDINGS FROM THE RAP INITIALLY INDICATE THE POTENTIAL FOR FREEZING DRIZZLE...THEN SATURATE TO MORE OF A IP/SN SOUNDING. HAVE MENTIONED ZL/IP FOR NOW WITH PCPN TYPE TRANSITIONING TO R/S DURING THE DAY FRIDAY. THERE IS STILL A FAIR AMOUNT OF UNCERTAINTY ON HOW MUCH PCPN WILL BE AROUND DURING THE DAY ON FRIDAY WITH THE NAM REMAINING THE DRIEST AMONGST THE MODELS. THE SURFACE COLD FRONT SWEEPS EASTWARD FRIDAY MORNING...AND THE MID LEVEL TROUGH EXTENDS ACROSS OUR CENTRAL CWA AROUND MIDDAY BEFORE TRANSLATING EASTWARD DURING THE AFTERNOON. MID LEVEL MOISTURE INCREASES AS THE TROUGH MOVES IN AND A NARROW BAND OF MID LEVEL FRONTOGENESIS/LIFT MOVE ACROSS FM LATE MORNING INTO EARLY AFTERNOON...MORE ALIGNED ACROSS THE EASTERN HALF OF OUR CWA. HAVE INCREASED POPS DURING THIS TIME FRAME AS SPC WRF...GFS...ECMWF AND EVEN THE GEM INDICATE THE POTENTIAL FOR BANDED PCPN. FORECAST SOUNDINGS INDICATE THE POSSIBILITY OF A QUICK SHOT OF SNOW INITIALLY THEN DRY OUT/WARM BEHIND THE TROUGH AND HAVE MAINTAINED A SIMPLE RAIN/SNOW MIX FOR PCPN TYPE ATTM. WITH A WARMING TEMP PROFILE...GENERALLY DO NOT EXPECT MUCH IN THE WAY OF ACCUMULATION BUT WOULD NOT BE SURPRISED TO SEE MINOR AMOUNTS...GENERALLY UNDER ONE HALF OF AN INCH. THE TROUGH AXIS SHIFTS EASTWARD BY FRIDAY EVENING WITH CONDITIONS DRYING OUT/CLOUDS DECREASING IN SUBSIDENCE BEHIND THE DEPARTING SYSTEM. .LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY) ISSUED AT 306 PM CST THU JAN 9 2014 OVERALL...THE LONG TERM PERIOD LOOKS TO BE MOSTLY DRY. BY FRIDAY NIGHT...THE MAIN TROUGH AXIS AND SURFACE LOW PRESSURE SYSTEM HAVE SHIFTED TO THE EAST OF THE PLAINS...WHILE AN UPPER LEVEL RIDGE AXIS SLOWLY BEGINS TO SHIFT ACROSS THE ROCKIES. WITH THIS RIDGE...AND A DEVELOPING LEE SURFACE TROUGH...SOUTHWEST WINDS WILL HELP BRING WARMER AIR TO THE PLAINS FOR SATURDAY. WENT A BIT ABOVE GUIDANCE FOR SATURDAY...WITH MOSTLY SUNNY SKIES AND SOUTHWEST WINDS...SEE NO REASON WHY WE CANNOT REACH THE UPPER 40S TO EVEN NEAR 50. BY SUNDAY...A WEAK UPPER LEVEL DISTURBANCE SHIFTS ACROSS THE PLAINS HELPING TO BREAK DOWN THE RIDGE. AS THE MAIN SURFACE LOW REMAINS WELL TO THE NORTH OF THE REGION...AN ASSOCIATED COLD FRONT WILL PASS THROUGH THE PLAINS SUNDAY. AT THIS POINT...WILL NOT REINTRODUCE POPS TO THE FORECAST AS THE SURFACE LOW REMAINS WELL TO THE NORTH. THAT BEING SAID...CANNOT RULE OUT A FEW SPRINKLES OR FLURRIES DURING THE DAY AND NIGHT ON SUNDAY. THE WAVE DEEPENS ACROSS THE PLAINS BY MONDAY...BRINGING COOLER 850 MB TEMPERATURES INTO THE OUTLOOK AREA. PERHAPS MONDAY MIGHT NEED TO BE A TAD COOLER THAN FORECAST BUT STILL CURRENTLY EXPECTING MID 40S FOR HIGHS. THROUGH THE REST OF THE LONG TERM...NUMEROUS WAVES CONTINUES TO DIVE SOUTH AND SKIRT ALONG THE PLAINS. HOWEVER...NONE OF THEM SUGGEST ANYTHING IN THE WAY OF PRECIPITATION OR A LONG LASTING COLD SPELL. IN FACT...RIDGING REBOUNDS ACROSS THE AREA BY WEDNESDAY BRINGING TEMPERATURES BACK UP TO NEAR 50. TOWARDS THURSDAY...YET ANOTHER UPPER LEVEL WAVE/CLOSED LOW WILL SHIFT THROUGH THE GREAT LAKES REGION DRAGGING A COLD FRONT ACROSS THE AREA. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 1111 AM CST THU JAN 9 2014 BIGGEST CHALLENGE FOR THE TAF PERIOD IS TIMING OF STRATUS AND HOW LOW CIGS MAY DROP. CURRENTLY THE STRATUS HAS BROKEN UP ACROSS KGRI BUT REMAINS WEST OF THE TERMINAL ATTM. SKIES ARE EXPECTED TO BE MAINLY SUNNY THROUGH THE AFTERNOON WITH CLOUDS INCREASING/CIGS LOWERING AFTER DARK. CIGS ARE EXPECTED TO DROP TO IFR AND POTENTIALLY LIFR TONIGHT AND VSBYS ARE ALSO EXPECTED TO LOWER TO AT LEAST MVFR IN BR. AN UPPER LEVEL DISTURBANCE WILL CROSS THE PLAINS EARLY FRIDAY AND THERE IS AN OUTSIDE CHANCE FOR SOME LIGHT RAIN/SNOW. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ SHORT TERM...FAY LONG TERM...SALTZMAN AVIATION...FAY
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1208 PM CST THU JAN 9 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 349 AM CST THU JAN 9 2014 SATELLITE IS GIVING A GOOD CLEARING SIGNAL WITH THE ARCTIC STRATUS DRAPED ALONG AND EAST OF HIGHWAY 83. H850 WINDS ARE CLEARLY SOUTHWEST SHUNTING THESE CLOUDS RAPIDLY EAST. THIS SHOULD PRODUCE SUNNY CONDITIONS TODAY. THE RAP IS SUGGESTING REFORMATION OF THE STRATUS TONIGHT FROM SOUTH TO NORTH BUT THE 06Z NAM INDICATES THESE CLOUDS REDEVELOP BUT FARTHER EAST AS A RESULT OF SOLID WEST AND SOUTHWEST 800 MB WINDS. SO THE FORECAST IS FOR CLEARING SKIES THIS MORNING AND INCREASING MIDLEVEL CLOUDINESS TONIGHT FROM WEST TO EAST WITH AN APPROACHING UPPER LEVEL DISTURBANCE CURRENTLY OVER WA/OR. HIGHS TODAY SHOULD RISE INTO THE 30S AND 40S AND THE FORECAST FOLLOWS THE WARM SIDE OF THE GUIDANCE ENVELOP. SIMILARLY...LOWS TONIGHT SHOULD FALL INTO JUST THE 20S WITH THE INCREASE IN CLOUDS AND WEST WINDS DEVELOPING TOWARD MORNING. THE MODELS ARE WOBBLING THE WA/OR UPPER LEVEL DISTURBANCE NORTH AND SOUTH ACROSS THE FORECAST AREA. THE FASTER 06Z NAM IS EVEN SHUNTING THE MOISTURE FOR THIS SYSTEM EAST OF THE FORECAST AREA SO ANY SNOW CHANCES REMAIN SLIGHT AT THIS TIME. THE ECM WAS THE FARTHEST SOUTH ACROSS KS WHILE THE THE GFS WAS ACROSS NRN NEB. THE GEM WAS EAST BUT NOT AS FAR AS THE NAM WHILE THE UKMET WAS IN THE MIDDLE LIKE THE 00Z NAM WHICH SHOWED 2 INCHES OF SNOW ACROSS LINCOLN AND CUSTER COUNTIES BY NOON FRIDAY. THE SNOW CHANCES HINGE ON THE TIMING OF THE RETURN MOISTURE VS THE ARRIVAL OF THE WA/OR UPPER LEVEL SUPPORT. IF THE WA/OR SYSTEM SLOWS THEN MOISTURE WOULD HAVE TIME TO RECOVER ACROSS THE FCST AREA AND SNOW COULD DEVELOP LATE TONIGHT. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 349 AM CST THU JAN 9 2014 TOMORROW A MID LEVEL TROUGH WILL PUSH ACROSS THE PLAINS. MODELS IN DECENT AGREEMENT WITH AN OPEN WAVE MOVING ACROSS KS/NEB DURING THE DAY...THEN LIFTING NORTHEAST FRIDAY NIGHT. THE 00Z NAM WAS AN OUTLIER WITH NEARLY 2 INCHES ACROSS PARTS OF SW INTO CENTRAL NEB DURING THE MID/LATE MORNING HOURS...WHICH WAS LOST FOR THE 06Z UPDATE. THIS PROVIDES HIGHER CONFIDENCE TO REST OF THE MODEL SUITE IN A LOW PRECIP/IF ANY TYPE OF AN EVENT. AS THE TROUGH AXIS PUSHES ACROSS THE AREA FRIDAY...AHEAD OF A DIVING JET TO THE WEST. WEAK UPPER LEVEL DIVERGENCE IN THE LEFT EXIT REGION AND WEAK OMEGA IN A SHALLOW DENDRITIC GROWTH ZONE...SHOULD RESULT IN FLURRIES/LIGHT SNOW...MAINLY SW INTO CENTRAL NEB. TEMPS WARM INTO THE UPPER 30S TO LOWER 40S WHICH SHOULD CAUSE A CHANGE OVER AT TIMES TO A MIX OR ALL LIQUID. SOUNDINGS SHOW LIMITED MOISTURE...AND LIFT GENERALLY ABOVE THE HIGHEST RH...THUS NOT EXPECTING MUCH IN THE WAY OF QPF FOR THE CWA. AS THE TROUGH PUSHES EAST FRIDAY NIGHT INTO SATURDAY...A WARM FRONT WILL SLIDE ACROSS THE AREA...AS WESTERN CONUS RIDGE EXPANDS. BY SATURDAY AFTERNOON 850MB TEMPS TO SOAR TO NEAR 10 C IN THE SW...ABOVE ZERO IN THE NE. GUIDANCE REBOUNDS TEMPS NICELY...AND FORECAST FOLLOWS. THIS RESULTS IN HIGHS REACHING THE LOW 50S SW...AND 40S ELSEWHERE. THE NEXT WEAK CLIPPER MOVES ACROSS THE NORTHERN PLAINS SAT NIGHT INTO SUN. COOLER AIR WILL FILL IN FROM THE NW...AND EXPECT AN INCREASE IN CLOUDS. DECENT MOISTURE WILL STREAM ACROSS THE ROCKIES...HOWEVER LL MOISTURE IS LACKING PER BUFKIT SOUNDINGS. QUICK PACE OF SYSTEM AND TOP DOWN SATURATION WILL LIMIT PRECIP REACHING THE GROUND. CONTINUED LOW SLGHT CHC POPS DURING THE DAY ON SUNDAY...ALTHOUGH IT MAY ONLY BE FLURRIES/SPRINKLES DEPENDING ON TEMPS. NEXT WEEK PATTERN CONTINUES TO SEE RIDGE TO THE WEST AND TROUGH ACROSS THE EAST...WITH FAST MOVING NW FLOW ACROSS THE AREA. CLIPPER SYSTEMS WILL BE A REGULAR OCCURRENCE...WITH TEMPS GENERALLY ABOVE NORMAL...ALTHOUGH SLIGHT FLUCTUATIONS OF 5 TO 10 DEGREES PENDING TIMING OF THE WAVES. MOISTURE REMAINS LIMITED...ESPECIALLY IN THE LOWER LEVELS...AND FORECAST IS DRY. WILL CONTINUE TO MONITOR AS PENDING TIME OF DAY...MAY NEED TO ADD A MENTION OF FLURRIES OR SPRINKLES WITH THE PASSING WAVES. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 1146 AM CST THU JAN 9 2014 A DISTURBANCE MOVING ACROSS THE AREA TONIGHT WILL BRING AN INCREASE IN CLOUD COVER...BUT DRY AIR FORECASTED IN THE MID AND LOWER LEVELS OF THE ATMOSPHERE SHOULD KEEP MOST PRECIPITATION AS VIRGA WITH LITTLE REACHING THE GROUND. THE DRY AIR SHOULD ALSO KEEP CLOUD BASES FAIRLY HIGH AROUND 9000 FT AGL...WITH VFR CONDITIONS EXPECTED TO PREVAIL. WINDS WILL BE SOUTH TO SOUTHWEST AT 10 TO 20 KTS THIS AFTERNOON...DECREASING SOME TONIGHT. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...CDC LONG TERM...MASEK AVIATION...TAYLOR
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
533 AM CST THU JAN 9 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 349 AM CST THU JAN 9 2014 SATELLITE IS GIVING A GOOD CLEARING SIGNAL WITH THE ARCTIC STRATUS DRAPED ALONG AND EAST OF HIGHWAY 83. H850 WINDS ARE CLEARLY SOUTHWEST SHUNTING THESE CLOUDS RAPIDLY EAST. THIS SHOULD PRODUCE SUNNY CONDITIONS TODAY. THE RAP IS SUGGESTING REFORMATION OF THE STRATUS TONIGHT FROM SOUTH TO NORTH BUT THE 06Z NAM INDICATES THESE CLOUDS REDEVELOP BUT FARTHER EAST AS A RESULT OF SOLID WEST AND SOUTHWEST 800 MB WINDS. SO THE FORECAST IS FOR CLEARING SKIES THIS MORNING AND INCREASING MIDLEVEL CLOUDINESS TONIGHT FROM WEST TO EAST WITH AN APPROACHING UPPER LEVEL DISTURBANCE CURRENTLY OVER WA/OR. HIGHS TODAY SHOULD RISE INTO THE 30S AND 40S AND THE FORECAST FOLLOWS THE WARM SIDE OF THE GUIDANCE ENVELOP. SIMILARLY...LOWS TONIGHT SHOULD FALL INTO JUST THE 20S WITH THE INCREASE IN CLOUDS AND WEST WINDS DEVELOPING TOWARD MORNING. THE MODELS ARE WOBBLING THE WA/OR UPPER LEVEL DISTURBANCE NORTH AND SOUTH ACROSS THE FORECAST AREA. THE FASTER 06Z NAM IS EVEN SHUNTING THE MOISTURE FOR THIS SYSTEM EAST OF THE FORECAST AREA SO ANY SNOW CHANCES REMAIN SLIGHT AT THIS TIME. THE ECM WAS THE FARTHEST SOUTH ACROSS KS WHILE THE THE GFS WAS ACROSS NRN NEB. THE GEM WAS EAST BUT NOT AS FAR AS THE NAM WHILE THE UKMET WAS IN THE MIDDLE LIKE THE 00Z NAM WHICH SHOWED 2 INCHES OF SNOW ACROSS LINCOLN AND CUSTER COUNTIES BY NOON FRIDAY. THE SNOW CHANCES HINGE ON THE TIMING OF THE RETURN MOISTURE VS THE ARRIVAL OF THE WA/OR UPPER LEVEL SUPPORT. IF THE WA/OR SYSTEM SLOWS THEN MOISTURE WOULD HAVE TIME TO RECOVER ACROSS THE FCST AREA AND SNOW COULD DEVELOP LATE TONIGHT. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 349 AM CST THU JAN 9 2014 TOMORROW A MID LEVEL TROUGH WILL PUSH ACROSS THE PLAINS. MODELS IN DECENT AGREEMENT WITH AN OPEN WAVE MOVING ACROSS KS/NEB DURING THE DAY...THEN LIFTING NORTHEAST FRIDAY NIGHT. THE 00Z NAM WAS AN OUTLIER WITH NEARLY 2 INCHES ACROSS PARTS OF SW INTO CENTRAL NEB DURING THE MID/LATE MORNING HOURS...WHICH WAS LOST FOR THE 06Z UPDATE. THIS PROVIDES HIGHER CONFIDENCE TO REST OF THE MODEL SUITE IN A LOW PRECIP/IF ANY TYPE OF AN EVENT. AS THE TROUGH AXIS PUSHES ACROSS THE AREA FRIDAY...AHEAD OF A DIVING JET TO THE WEST. WEAK UPPER LEVEL DIVERGENCE IN THE LEFT EXIT REGION AND WEAK OMEGA IN A SHALLOW DENDRITIC GROWTH ZONE...SHOULD RESULT IN FLURRIES/LIGHT SNOW...MAINLY SW INTO CENTRAL NEB. TEMPS WARM INTO THE UPPER 30S TO LOWER 40S WHICH SHOULD CAUSE A CHANGE OVER AT TIMES TO A MIX OR ALL LIQUID. SOUNDINGS SHOW LIMITED MOISTURE...AND LIFT GENERALLY ABOVE THE HIGHEST RH...THUS NOT EXPECTING MUCH IN THE WAY OF QPF FOR THE CWA. AS THE TROUGH PUSHES EAST FRIDAY NIGHT INTO SATURDAY...A WARM FRONT WILL SLIDE ACROSS THE AREA...AS WESTERN CONUS RIDGE EXPANDS. BY SATURDAY AFTERNOON 850MB TEMPS TO SOAR TO NEAR 10 C IN THE SW...ABOVE ZERO IN THE NE. GUIDANCE REBOUNDS TEMPS NICELY...AND FORECAST FOLLOWS. THIS RESULTS IN HIGHS REACHING THE LOW 50S SW...AND 40S ELSEWHERE. THE NEXT WEAK CLIPPER MOVES ACROSS THE NORTHERN PLAINS SAT NIGHT INTO SUN. COOLER AIR WILL FILL IN FROM THE NW...AND EXPECT AN INCREASE IN CLOUDS. DECENT MOISTURE WILL STREAM ACROSS THE ROCKIES...HOWEVER LL MOISTURE IS LACKING PER BUFKIT SOUNDINGS. QUICK PACE OF SYSTEM AND TOP DOWN SATURATION WILL LIMIT PRECIP REACHING THE GROUND. CONTINUED LOW SLGHT CHC POPS DURING THE DAY ON SUNDAY...ALTHOUGH IT MAY ONLY BE FLURRIES/SPRINKLES DEPENDING ON TEMPS. NEXT WEEK PATTERN CONTINUES TO SEE RIDGE TO THE WEST AND TROUGH ACROSS THE EAST...WITH FAST MOVING NW FLOW ACROSS THE AREA. CLIPPER SYSTEMS WILL BE A REGULAR OCCURRENCE...WITH TEMPS GENERALLY ABOVE NORMAL...ALTHOUGH SLIGHT FLUCTUATIONS OF 5 TO 10 DEGREES PENDING TIMING OF THE WAVES. MOISTURE REMAINS LIMITED...ESPECIALLY IN THE LOWER LEVELS...AND FORECAST IS DRY. WILL CONTINUE TO MONITOR AS PENDING TIME OF DAY...MAY NEED TO ADD A MENTION OF FLURRIES OR SPRINKLES WITH THE PASSING WAVES. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING) ISSUED AT 533 AM CST THU JAN 9 2014 THE MVFR/IFR CIGS AND VSBY EAST OF HIGHWAY 83 SHOULD MOVE EAST OF THE FCST AREA BY 15Z-18Z. VFR IS EXPECTED THEREAFTER THROUGH 06Z TONIGHT. AN AREA OF MVFR CIGS COULD MOVE INTO NWRN NEB AFTER 06Z TONIGHT. THESE CLOUDS WOULD BE ASSOCIATED WITH THE UPPER LEVEL DISTURBANCE ACROSS OR/WA THIS MORNING. SOME MODELS ALSO SUGGEST THE POTENTIAL FOR MVFR/IFR CIGS THIS EVENING ACROSS THE FAR ERN EDGE OF THE FCST AREA...ALONG OR EAST OF HIGHWAY 183. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...CDC LONG TERM...MASEK AVIATION...CDC
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
353 AM CST THU JAN 9 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 349 AM CST THU JAN 9 2014 SATELLITE IS GIVING A GOOD CLEARING SIGNAL WITH THE ARCTIC STRATUS DRAPED ALONG AND EAST OF HIGHWAY 83. H850 WINDS ARE CLEARLY SOUTHWEST SHUNTING THESE CLOUDS RAPIDLY EAST. THIS SHOULD PRODUCE SUNNY CONDITIONS TODAY. THE RAP IS SUGGESTING REFORMATION OF THE STRATUS TONIGHT FROM SOUTH TO NORTH BUT THE 06Z NAM INDICATES THESE CLOUDS REDEVELOP BUT FARTHER EAST AS A RESULT OF SOLID WEST AND SOUTHWEST 800 MB WINDS. SO THE FORECAST IS FOR CLEARING SKIES THIS MORNING AND INCREASING MIDLEVEL CLOUDINESS TONIGHT FROM WEST TO EAST WITH AN APPROACHING UPPER LEVEL DISTURBANCE CURRENTLY OVER WA/OR. HIGHS TODAY SHOULD RISE INTO THE 30S AND 40S AND THE FORECAST FOLLOWS THE WARM SIDE OF THE GUIDANCE ENVELOP. SIMILARLY...LOWS TONIGHT SHOULD FALL INTO JUST THE 20S WITH THE INCREASE IN CLOUDS AND WEST WINDS DEVELOPING TOWARD MORNING. THE MODELS ARE WOBBLING THE WA/OR UPPER LEVEL DISTURBANCE NORTH AND SOUTH ACROSS THE FORECAST AREA. THE FASTER 06Z NAM IS EVEN SHUNTING THE MOISTURE FOR THIS SYSTEM EAST OF THE FORECAST AREA SO ANY SNOW CHANCES REMAIN SLIGHT AT THIS TIME. THE ECM WAS THE FARTHEST SOUTH ACROSS KS WHILE THE THE GFS WAS ACROSS NRN NEB. THE GEM WAS EAST BUT NOT AS FAR AS THE NAM WHILE THE UKMET WAS IN THE MIDDLE LIKE THE 00Z NAM WHICH SHOWED 2 INCHES OF SNOW ACROSS LINCOLN AND CUSTER COUNTIES BY NOON FRIDAY. THE SNOW CHANCES HINGE ON THE TIMING OF THE RETURN MOISTURE VS THE ARRIVAL OF THE WA/OR UPPER LEVEL SUPPORT. IF THE WA/OR SYSTEM SLOWS THEN MOISTURE WOULD HAVE TIME TO RECOVER ACROSS THE FCST AREA AND SNOW COULD DEVELOP LATE TONIGHT. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 349 AM CST THU JAN 9 2014 TOMORROW A MID LEVEL TROUGH WILL PUSH ACROSS THE PLAINS. MODELS IN DECENT AGREEMENT WITH AN OPEN WAVE MOVING ACROSS KS/NEB DURING THE DAY...THEN LIFTING NORTHEAST FRIDAY NIGHT. THE 00Z NAM WAS AN OUTLIER WITH NEARLY 2 INCHES ACROSS PARTS OF SW INTO CENTRAL NEB DURING THE MID/LATE MORNING HOURS...WHICH WAS LOST FOR THE 06Z UPDATE. THIS PROVIDES HIGHER CONFIDENCE TO REST OF THE MODEL SUITE IN A LOW PRECIP/IF ANY TYPE OF AN EVENT. AS THE TROUGH AXIS PUSHES ACROSS THE AREA FRIDAY...AHEAD OF A DIVING JET TO THE WEST. WEAK UPPER LEVEL DIVERGENCE IN THE LEFT EXIT REGION AND WEAK OMEGA IN A SHALLOW DENDRITIC GROWTH ZONE...SHOULD RESULT IN FLURRIES/LIGHT SNOW...MAINLY SW INTO CENTRAL NEB. TEMPS WARM INTO THE UPPER 30S TO LOWER 40S WHICH SHOULD CAUSE A CHANGE OVER AT TIMES TO A MIX OR ALL LIQUID. SOUNDINGS SHOW LIMITED MOISTURE...AND LIFT GENERALLY ABOVE THE HIGHEST RH...THUS NOT EXPECTING MUCH IN THE WAY OF QPF FOR THE CWA. AS THE TROUGH PUSHES EAST FRIDAY NIGHT INTO SATURDAY...A WARM FRONT WILL SLIDE ACROSS THE AREA...AS WESTERN CONUS RIDGE EXPANDS. BY SATURDAY AFTERNOON 850MB TEMPS TO SOAR TO NEAR 10 C IN THE SW...ABOVE ZERO IN THE NE. GUIDANCE REBOUNDS TEMPS NICELY...AND FORECAST FOLLOWS. THIS RESULTS IN HIGHS REACHING THE LOW 50S SW...AND 40S ELSEWHERE. THE NEXT WEAK CLIPPER MOVES ACROSS THE NORTHERN PLAINS SAT NIGHT INTO SUN. COOLER AIR WILL FILL IN FROM THE NW...AND EXPECT AN INCREASE IN CLOUDS. DECENT MOISTURE WILL STREAM ACROSS THE ROCKIES...HOWEVER LL MOISTURE IS LACKING PER BUFKIT SOUNDINGS. QUICK PACE OF SYSTEM AND TOP DOWN SATURATION WILL LIMIT PRECIP REACHING THE GROUND. CONTINUED LOW SLGHT CHC POPS DURING THE DAY ON SUNDAY...ALTHOUGH IT MAY ONLY BE FLURRIES/SPRINKLES DEPENDING ON TEMPS. NEXT WEEK PATTERN CONTINUES TO SEE RIDGE TO THE WEST AND TROUGH ACROSS THE EAST...WITH FAST MOVING NW FLOW ACROSS THE AREA. CLIPPER SYSTEMS WILL BE A REGULAR OCCURRENCE...WITH TEMPS GENERALLY ABOVE NORMAL...ALTHOUGH SLIGHT FLUCTUATIONS OF 5 TO 10 DEGREES PENDING TIMING OF THE WAVES. MOISTURE REMAINS LIMITED...ESPECIALLY IN THE LOWER LEVELS...AND FORECAST IS DRY. WILL CONTINUE TO MONITOR AS PENDING TIME OF DAY...MAY NEED TO ADD A MENTION OF FLURRIES OR SPRINKLES WITH THE PASSING WAVES. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT) ISSUED AT 1147 PM CST WED JAN 8 2014 STRATUS CONTINUES TO EXPAND ACROSS THE CWA...HOWEVER THE WESTWARD EXPANSION HAS BEEN DIMINISHING THE LAST HOUR. STRATUS IS EXPECTED TO CONTINUE TO LIFT NORTH AS SOUTHERLY WINDS INCREASE MOISTURE FROM THE SOUTH...WITH IMPACT TO KVTN IN THE NEXT COUPLE OF HOURS. SOME CONCERN THAT ALONG THE WESTERN EDGE SOME REDUCED VSBY IS POSSIBLE...FROM FOG...HOWEVER OBS HAVE NOT SHOWN ANY YET. WILL CONTINUE TO MONITOR FOR POSSIBLE DEVELOPMENT...ALTHOUGH AT THIS TIME EXPECT IT TO BE WEST OF THE TERMINAL SITES. TOMORROW MORNING THE IFR STATUS WILL MIX OUT AND SKIES BECOME SCT/BKN VFR...AND WINDS REMAIN SOUTHERLY. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...CDC LONG TERM...MASEK AVIATION...MASEK
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1202 AM CST THU JAN 9 2014 .UPDATE... ISSUED AT 1202 AM CST WED JAN 8 2014 FCST TEMPS AND DEWPOINTS WERE RUNNING A LITTLE LOW COMPARED TO REALITY...ESPECIALLY FROM THE TRI-CITIES N AND E. USED CONSENSUS OF SHORT-TERM MODELS TO INCREASE THEM THRU 9 AM...WHICH MODESTLY BROUGHT LOW TEMPS UP ABOUT 3F. A VERY COMPLEX CLOUD COVER SITUATION IS UNFOLDING...WITH A TONGUE OF CLEAR SKIES FROM STOCKTON KS UP TO THE TRI-CITIES...WITH LOW STRATUS AND LIGHT FOG TO THE NW...AND MID-LEVEL CIGS TO THE SE. UNCERTAINTY IS HIGH IN HOW SKY COVER EVOLVES THE REST OF THE NIGHT ...BUT THE UPS CROSSOVER TECHNIQUE SUGGESTS MVFR FOG AND POSSIBLY A TOUCH OF IFR FOG WILL BE POSSIBLE. WINDS ARE EXPECTED TO REMAIN 5-10 MPH THE REST OF THE NIGHT...WHICH WILL HELP MITIGATE EXTREMELY LOW VSBYS. GIVEN THE LACK OF STRATUS OVER THE SE 1/2 OF THE FCST AREA...THE THREAT FOR FRZG DRIZZLE HAS BEEN WITHDRAWN. OVERALL...EXPECT VARIABLE CLOUDS THE REST OF THE NIGHT WITH POTENTIAL FOR PATCHY FOG TO DEVELOP. UPDATE ISSUED AT 953 PM CST WED JAN 8 2014 UPDATED THE FORECAST TO INCREASE SKY COVER DUE TO STRATUS COVERAGE AND BRING THE SLIGHT CHANCE OF DRIZZLE JUST A LITTLE FARTHER TO THE NORTH AS NAM SOUNDINGS INDICATE...AS WELL AS THE QPF FIELD. ALTHOUGH BROKEN BOW HAS DIPPED TO AS LOW AS 2 MILES VISIBILITY...THIS APPEARS TO BE ISOLATED...SO LEFT FOG OUT OF THE FORECAST. GFS LAMP DATA SEEMS TO BE DOING PRETTY WELL WITH THE CURRENT SITUATION...AND THIS WOULD INDICATE NOT INCLUDING ANY FOG AS WELL. && .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 345 PM CST WED JAN 8 2014 LIGHT SNOW ASSOCIATED WITH A PASSING MID LEVEL SHORTWAVE TROUGH IS STARTING TO WIND DOWN EARLY THIS AFTERNOON AS THE SYSTEM TRANSLATES EASTWARDS. ON AVERAGE...SNOW AMOUNTS HAVE RANGED FROM ONE HALF INCH TO ONE INCH WITH SOME LOCATIONS WITH MORE SNOW AND OTHERS WITH LESS. HEADING INTO TONIGHT...AN AREA OF LOW CLOUD COVER/STRATUS WILL LINGER INTO TONIGHT BUT WILL BEGIN TO BREAK UP AND SHIFT EASTWARD TOWARD MORNING WHILE STRATUS ACROSS THE SOUTHERN PLAINS WILL WORK NORTHWARD ACROSS EASTERN KANSAS/SOUTHERN NEBRASKA. THE LOW CLOUDS WILL SETTLE ALONG A SURFACE RIDGE AXIS WHICH WILL GRADUALLY BUILD SOUTHEAST TOWARD IA/IL. IN RETURN FLOW ON THE BACK SIDE OF THE RIDGE...SOUTHERLY WINDS/WAA WILL SPREAD W/E TONIGHT AND THURSDAY. HAVE MAINTAINED SLIGHT CHANCES FOR LIGHT FREEZING DRIZZLE ACROSS OUR FAR SOUTHEAST ZONES WHERE MODELS INDICATE PRESENCE OF DEEPER LLVL MOISTURE AND WAA/LIFT OVER THE LOW CLOUDS. FORECAST SOUNDINGS INDICATE THE GFS IS DEEPER WITH THE LLVL MOISTURE THAN THE NAM BUT IS PRESENT NONTHELESS. OUR AREA IS ON THE BUFFER OF THE BETTER MOISTURE AND LIFT BUT SREF CONTINUES TO INDICATE LOW POPS AND THE GFS HAS BEEN HIT OR MISS FOR LIGHT PCPN IN THIS AREA TONIGHT. ANOTHER CONCERN FOR TONIGHT IS THE POTENTIAL FOR FOG DEVELOPMENT AS HALF OF THE SHORT TERM MODELS SUGGEST LOW VISIBILITIES ON THE EDGE OF THE STRATUS IN THE RETURN FLOW. THE RAP IS THE MOST ROBUST IN SUGGESTING THE POTENTIAL FOR DENSE FOG AND THE HRRR IS TRENDING TOWARD A FOG SOLUTION...HOWEVER THE NAM AND THE SREF DO NOT. WITH WINDS REMAINING FAIRLY STEADY WILL TREND WITH MORE OF STRATUS VS FOG FOR NOW AND HAVE THE NEXT SHIFT MONITOR THE FOG POTENTIAL CLOSELY. THURSDAY IS STILL LOOKING DRY DURING THE DAY WITH MODERATING TEMPERATURES FROM WEST TO EAST IN THE RETURN FLOW AND AS CLOUDS DEPART WEST/EAST. HAVE WENT WITH HIGHS IN THE 30S...AND TEMPS MAY STRUGGLE TO SOME DEGREE WHERE AN INCH OR SO OF SNOW IS ON THE GROUND. REGARDLESS...TEMPS WILL STILL BE ON THE UPSWING COMPARED TO TODAY. .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 345 PM CST WED JAN 8 2014 PRIMARY FORECAST CONCERN THROUGH THE LONG TERM PERIOD LIES WITH PRECIP CHANCES IN THE FIRST 24 HRS OR SO. THURSDAY EVENING STARTS OUT WITH W/SWRLY FLOW IN PLACE IN THE UPPER LEVELS OVER THE REGION...AS A SHORTWAVE TROUGH IS MAKING ITS WAY THROUGH THE ROCKIES. THROUGH THE EVENING/OVERNIGHT HOURS..THIS TROUGH SLIDES E/SE ONTO THE HIGH PLAINS...THEN THROUGH THE DAYTIME HOURS WILL WORK THROUGH THE NRN/CENTRAL PLAINS. BY 00Z THE 5/700MB TROUGH AXIS IS EXPECTED TO BE SET UP THROUGH ERN NEB/KS. CONFIDENCE IN THE THURSDAY EVENING THROUGH DAYTIME FRIDAY PERIOD IS NOT ON THE HIGH SIDE...MAINLY DUE TO UNCERTAINTIES WITH THE LOWER LEVEL/SFC TEMPERATURES...AND BECAUSE THE LATEST MODEL RUNS HAVE SHOWN A E/SE SHIFT OF THE BETTER PRECIP CHANCES. ALREADY BY 00Z THURSDAY...THE SFC SHOWS A TROUGH OF LOW PRESSURE OVER THE HIGH PLAINS...RESULTING IN SRLY WINDS SET UP OVER THE CWA. THROUGH SUNRISE FRIDAY...THERE IS LITTLE CHANGE WITH THAT...WITH MODELS ALSO SHOWING AN INCREASE IN THE SWRLY FLOW AT 850MB...HELPING WITH SOME WARM AIR/MOISTURE TRANSPORT. CONTINUE TO KEEP ANY POPS OUT OF THE FORECAST THROUGH 12Z...WITH ONLY THE FZDZ MENTION GOING IN THE FAR SOUTH...AS THAT SRLY FLOW HELPS TO MOISTEN UP LOWER PORTIONS OF THE ATMOSPHERIC PROFILE. THROUGH THE 12-18Z PERIOD...INHERITED FORECAST ONLY HAD 50 POPS GOING IN SERN PORTIONS OF THE CWA...SO WAS FINE KEEPING THAT GOING...BUT DID TRIM THE WRN EDGE. THE LATEST MODELS RUNS HAVE SHOWN THE MUCH BETTER ISENTROPIC LIFT/WARM AIR/MOISTURE ADVECTION WITH THE CORRIDOR OF THE LLJ OUT AHEAD OF THE SYSTEM BEING E/SE OF THE CWA...ALONG/AHEAD OF THE MAIN SFC/LOWER LEVEL COOL FRONT. IF THIS TREND CONTINUES...POPS MAY NEED TO BE LOWERED FURTHER. ALONG WITH THIS...MODELS SHOWING THE POTENTIAL FOR A SECOND AREA OF PRECIPITATION DEVELOPING FURTHER WEST ALONG THE 7/500 MB TROUGH AXIS...THEN SWINGING THROUGH AT LEAST PORTIONS OF THE CWA...SO ADDED SOME LOW POPS BACK WEST FOR THE AFTERNOON HRS. MOISTURE AVAILABILITY THAT FAR WEST BEHIND THE SFC/LOWER LEVEL FRONT WONT BE AS GOOD...SO NOT EXPECTING ANYTHING THAT DEVELOPS ALONG THAT MID LEVEL AXIS TO AMOUNT TO A LOT. ALONG WITH UNCERTAINTY WITH HOW MUCH PRECIP THE CWA WILL ACTUALLY SEE...THE THERMAL PROFILE WITH ANY PRECIP THAT FALLS IS ALSO STILL IN QUESTION. STILL A CONCERN WITH A WINTRY MIX OF PRECIP DURING THE MORNING HOURS...AND WHILE FORECAST SOUNDINGS DO SHOW A WARMER LAYER OFF THE SFC...ITS NOT OVERLY WARM...SO WHERE THE SFC TEMPS ARE BELOW FREEZING...SOME QUESTION WITH WHETHER IT WOULD FALL AS FZRA OR SLEET. MODELS ALSO DIFFER ON SFC TEMPS...KEEPING SOME LOCATIONS ABOVE FREEZING...SO KEPT THE POSSIBILITY OF RAIN IN AS WELL. DURING THE AFTERNOON HOURS...MAIN CONCERN LIES WITH SFC TEMPS WITH MOST MODELS SHOWING THE 850MB TEMPS DROPPING BELOW ZERO...SO HAVE PTYPE MENTION AS RA/SN. PLENTY OF THINGS TO IRON OVER THE NEXT FEW SHIFTS. AS WE GET INTO THE FIRST HALF OF THE UPCOMING WEEKEND...THE FORECAST REMAINS A DRY ONE...WITH NORTHWESTERLY FLOW TAKING OVER IN THE UPPER LEVELS IN THE WAKE OF THIS LATEST DISTURBANCE. EXPECTING TO SEE DIMINISHING CLOUD COVER...WITH A BUMP UP IN TEMPERATURES. MODERATING TEMPS ALOFT COMBINED WITH THE DOWNSLOPING WRLY COMPONENT TO THE WINDS LOOKS TO HELP TEMPS AT LEAST RISE INTO THE 40S...WITH LOWER 50S NOT OUT OF THE QUESTION IN THE SOUTHWEST. SUNDAY/SUNDAY IS THE ONLY OTHER TIME FRAME WITH ANY PRECIP CHANCES GOING...AND THEY REMAIN ON THE LOW SIDE. ANOTHER UPPER LEVEL SHORTWAVE TROUGH SLIDES OUT OF THE ROCKIES AND THROUGH THE PLAINS...WITH MODELS IN PRETTY GOOD AGREEMENT NOT SHOWING MUCH IN THE WAY OF QPF OVER THE AREA...WITH REALLY NO CHANCE FOR BETTER MOISTURE TO ADVECT BACK IN BEFORE IT GETS HERE. ONLY SLIGHT DIFFERENCES EXIST BETWEEN MODELS WITH TIMING...WITH THE GFS/GEM A TOUCH QUICKER SHOWING IT MAINLY A DAYTIME SUNDAY EVENT...WITH THE ECMWF LINGERING THINGS INTO THE EVENING HOURS. THIS DISTURBANCE WILL USHER IN A REINFORCING SHOT OF NORTHWESTERLY WINDS...AND COOLER AIR - WHICH LOOKS TO MAINLY AFFECT THE OVERNIGHT HOURS AND QUICKLY SLIDE EAST. CURRENT FORECAST HIGHS ON SUNDAY ARE ONCE AGAIN IN THE 40S...WITH SUNDAY NIGHT/MONDAY AM LOWS IN THE MID 20S. MONDAY THROUGH WEDNESDAY...THE FORECAST REMAINS DRY...BUT WILL HAVE TO KEEP AN EYE ON A DISTURBANCE MOVING THROUGH TUESDAY. AT THIS POINT MODELS IN GOOD AGREEMENT KEEPING PRECIP TO THE N/NE OF THE CWA...BUT MAY SEE SOME TEMP ADJUSTMENTS FOR TUESDAY AS ANOTHER SHORT LIVED BATCH OF COOLER AIR MOVES THROUGH. TIMING OF ALL OF THIS IS THE MAIN QUESTION. HIGHS REMAIN GENERALLY IN THE 40S...WITH LOWS IN THE 20S. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT) ISSUED AT 1202 AM CST WED JAN 8 2014 REST OF TONIGHT THRU 12Z: HIGHLY VARIABLE CLOUD COVER EXPECTED. SATELLITE SHOWS CLEARING APPROACHING FROM THE SW. SO EXPECT MVFR CIG TO BECOME SCT. WHETHER THE STRATUS RETURNS BEFORE DAYBREAK REMAINS HIGHLY UNCERTAIN. CLEARING SUGGESTS POTENTIAL FOR MVFR VSBYS IN FOG /AND POSSIBLY IFR/ WITH TEMPS AND DEWPOINTS CLOSE. WINDS WILL REMAIN SE UNDER 10 KTS. CONFIDENCE: LOW THU: ANY MORNING FOG DISSIPATES. UNSURE IF STRATUS WILL BE AROUND. EXPECT VFR TO DEVELOP BY 15Z WITH POTENTIAL FOR SOME SCT STRATOCU AROUND 2K FT. S WINDS WILL INCREASE AND GUST UP TO 23 KTS AT TIMES. CONFIDENCE: LOW THU EVE: HIGH LOW-LEVEL MOISTURE WILL CONTINUE WHICH SUGGESTS THE RETURN OF FOG/STRATUS. HOWEVER...S WINDS 10-15 KTS WILL KEEP THE LOW-LEVELS MIXED. HOW THIS TRANSLATES TO CIGS/VSBYS REMAINS UNCERTAIN...BUT SHOULD MITIGATE THE WORST CASE SCENARIO /VLIFR/. CONFIDENCE: LOW && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ UPDATE...HALBLAUB SHORT TERM...FAY LONG TERM...ADO AVIATION...HALBLAUB
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1014 PM CST WED JAN 8 2014 .UPDATE... ISSUED AT 953 PM CST WED JAN 8 2014 UPDATED THE FORECAST TO INCREASE SKY COVER DUE TO STRATUS COVERAGE AND BRING THE SLIGHT CHANCE OF DRIZZLE JUST A LITTLE FARTHER TO THE NORTH AS NAM SOUNDINGS INDICATE...AS WELL AS THE QPF FIELD. ALTHOUGH BROKEN BOW HAS DIPPED TO AS LOW AS 2 MILES VISIBILITY...THIS APPEARS TO BE ISOLATED...SO LEFT FOG OUT OF THE FORECAST. GFS LAMP DATA SEEMS TO BE DOING PRETTY WELL WITH THE CURRENT SITUATION...AND THIS WOULD INDICATE NOT INCLUDING ANY FOG AS WELL. && .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 345 PM CST WED JAN 8 2014 LIGHT SNOW ASSOCIATED WITH A PASSING MID LEVEL SHORTWAVE TROUGH IS STARTING TO WIND DOWN EARLY THIS AFTERNOON AS THE SYSTEM TRANSLATES EASTWARDS. ON AVERAGE...SNOW AMOUNTS HAVE RANGED FROM ONE HALF INCH TO ONE INCH WITH SOME LOCATIONS WITH MORE SNOW AND OTHERS WITH LESS. HEADING INTO TONIGHT...AN AREA OF LOW CLOUD COVER/STRATUS WILL LINGER INTO TONIGHT BUT WILL BEGIN TO BREAK UP AND SHIFT EASTWARD TOWARD MORNING WHILE STRATUS ACROSS THE SOUTHERN PLAINS WILL WORK NORTHWARD ACROSS EASTERN KANSAS/SOUTHERN NEBRASKA. THE LOW CLOUDS WILL SETTLE ALONG A SURFACE RIDGE AXIS WHICH WILL GRADUALLY BUILD SOUTHEAST TOWARD IA/IL. IN RETURN FLOW ON THE BACK SIDE OF THE RIDGE...SOUTHERLY WINDS/WAA WILL SPREAD W/E TONIGHT AND THURSDAY. HAVE MAINTAINED SLIGHT CHANCES FOR LIGHT FREEZING DRIZZLE ACROSS OUR FAR SOUTHEAST ZONES WHERE MODELS INDICATE PRESENCE OF DEEPER LLVL MOISTURE AND WAA/LIFT OVER THE LOW CLOUDS. FORECAST SOUNDINGS INDICATE THE GFS IS DEEPER WITH THE LLVL MOISTURE THAN THE NAM BUT IS PRESENT NONTHELESS. OUR AREA IS ON THE BUFFER OF THE BETTER MOISTURE AND LIFT BUT SREF CONTINUES TO INDICATE LOW POPS AND THE GFS HAS BEEN HIT OR MISS FOR LIGHT PCPN IN THIS AREA TONIGHT. ANOTHER CONCERN FOR TONIGHT IS THE POTENTIAL FOR FOG DEVELOPMENT AS HALF OF THE SHORT TERM MODELS SUGGEST LOW VISIBILITIES ON THE EDGE OF THE STRATUS IN THE RETURN FLOW. THE RAP IS THE MOST ROBUST IN SUGGESTING THE POTENTIAL FOR DENSE FOG AND THE HRRR IS TRENDING TOWARD A FOG SOLUTION...HOWEVER THE NAM AND THE SREF DO NOT. WITH WINDS REMAINING FAIRLY STEADY WILL TREND WITH MORE OF STRATUS VS FOG FOR NOW AND HAVE THE NEXT SHIFT MONITOR THE FOG POTENTIAL CLOSELY. THURSDAY IS STILL LOOKING DRY DURING THE DAY WITH MODERATING TEMPERATURES FROM WEST TO EAST IN THE RETURN FLOW AND AS CLOUDS DEPART WEST/EAST. HAVE WENT WITH HIGHS IN THE 30S...AND TEMPS MAY STRUGGLE TO SOME DEGREE WHERE AN INCH OR SO OF SNOW IS ON THE GROUND. REGARDLESS...TEMPS WILL STILL BE ON THE UPSWING COMPARED TO TODAY. .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 345 PM CST WED JAN 8 2014 PRIMARY FORECAST CONCERN THROUGH THE LONG TERM PERIOD LIES WITH PRECIP CHANCES IN THE FIRST 24 HRS OR SO. THURSDAY EVENING STARTS OUT WITH W/SWRLY FLOW IN PLACE IN THE UPPER LEVELS OVER THE REGION...AS A SHORTWAVE TROUGH IS MAKING ITS WAY THROUGH THE ROCKIES. THROUGH THE EVENING/OVERNIGHT HOURS..THIS TROUGH SLIDES E/SE ONTO THE HIGH PLAINS...THEN THROUGH THE DAYTIME HOURS WILL WORK THROUGH THE NRN/CENTRAL PLAINS. BY 00Z THE 5/700MB TROUGH AXIS IS EXPECTED TO BE SET UP THROUGH ERN NEB/KS. CONFIDENCE IN THE THURSDAY EVENING THROUGH DAYTIME FRIDAY PERIOD IS NOT ON THE HIGH SIDE...MAINLY DUE TO UNCERTAINTIES WITH THE LOWER LEVEL/SFC TEMPERATURES...AND BECAUSE THE LATEST MODEL RUNS HAVE SHOWN A E/SE SHIFT OF THE BETTER PRECIP CHANCES. ALREADY BY 00Z THURSDAY...THE SFC SHOWS A TROUGH OF LOW PRESSURE OVER THE HIGH PLAINS...RESULTING IN SRLY WINDS SET UP OVER THE CWA. THROUGH SUNRISE FRIDAY...THERE IS LITTLE CHANGE WITH THAT...WITH MODELS ALSO SHOWING AN INCREASE IN THE SWRLY FLOW AT 850MB...HELPING WITH SOME WARM AIR/MOISTURE TRANSPORT. CONTINUE TO KEEP ANY POPS OUT OF THE FORECAST THROUGH 12Z...WITH ONLY THE FZDZ MENTION GOING IN THE FAR SOUTH...AS THAT SRLY FLOW HELPS TO MOISTEN UP LOWER PORTIONS OF THE ATMOSPHERIC PROFILE. THROUGH THE 12-18Z PERIOD...INHERITED FORECAST ONLY HAD 50 POPS GOING IN SERN PORTIONS OF THE CWA...SO WAS FINE KEEPING THAT GOING...BUT DID TRIM THE WRN EDGE. THE LATEST MODELS RUNS HAVE SHOWN THE MUCH BETTER ISENTROPIC LIFT/WARM AIR/MOISTURE ADVECTION WITH THE CORRIDOR OF THE LLJ OUT AHEAD OF THE SYSTEM BEING E/SE OF THE CWA...ALONG/AHEAD OF THE MAIN SFC/LOWER LEVEL COOL FRONT. IF THIS TREND CONTINUES...POPS MAY NEED TO BE LOWERED FURTHER. ALONG WITH THIS...MODELS SHOWING THE POTENTIAL FOR A SECOND AREA OF PRECIPITATION DEVELOPING FURTHER WEST ALONG THE 7/500 MB TROUGH AXIS...THEN SWINGING THROUGH AT LEAST PORTIONS OF THE CWA...SO ADDED SOME LOW POPS BACK WEST FOR THE AFTERNOON HRS. MOISTURE AVAILABILITY THAT FAR WEST BEHIND THE SFC/LOWER LEVEL FRONT WONT BE AS GOOD...SO NOT EXPECTING ANYTHING THAT DEVELOPS ALONG THAT MID LEVEL AXIS TO AMOUNT TO A LOT. ALONG WITH UNCERTAINTY WITH HOW MUCH PRECIP THE CWA WILL ACTUALLY SEE...THE THERMAL PROFILE WITH ANY PRECIP THAT FALLS IS ALSO STILL IN QUESTION. STILL A CONCERN WITH A WINTRY MIX OF PRECIP DURING THE MORNING HOURS...AND WHILE FORECAST SOUNDINGS DO SHOW A WARMER LAYER OFF THE SFC...ITS NOT OVERLY WARM...SO WHERE THE SFC TEMPS ARE BELOW FREEZING...SOME QUESTION WITH WHETHER IT WOULD FALL AS FZRA OR SLEET. MODELS ALSO DIFFER ON SFC TEMPS...KEEPING SOME LOCATIONS ABOVE FREEZING...SO KEPT THE POSSIBILITY OF RAIN IN AS WELL. DURING THE AFTERNOON HOURS...MAIN CONCERN LIES WITH SFC TEMPS WITH MOST MODELS SHOWING THE 850MB TEMPS DROPPING BELOW ZERO...SO HAVE PTYPE MENTION AS RA/SN. PLENTY OF THINGS TO IRON OVER THE NEXT FEW SHIFTS. AS WE GET INTO THE FIRST HALF OF THE UPCOMING WEEKEND...THE FORECAST REMAINS A DRY ONE...WITH NORTHWESTERLY FLOW TAKING OVER IN THE UPPER LEVELS IN THE WAKE OF THIS LATEST DISTURBANCE. EXPECTING TO SEE DIMINISHING CLOUD COVER...WITH A BUMP UP IN TEMPERATURES. MODERATING TEMPS ALOFT COMBINED WITH THE DOWNSLOPING WRLY COMPONENT TO THE WINDS LOOKS TO HELP TEMPS AT LEAST RISE INTO THE 40S...WITH LOWER 50S NOT OUT OF THE QUESTION IN THE SOUTHWEST. SUNDAY/SUNDAY IS THE ONLY OTHER TIME FRAME WITH ANY PRECIP CHANCES GOING...AND THEY REMAIN ON THE LOW SIDE. ANOTHER UPPER LEVEL SHORTWAVE TROUGH SLIDES OUT OF THE ROCKIES AND THROUGH THE PLAINS...WITH MODELS IN PRETTY GOOD AGREEMENT NOT SHOWING MUCH IN THE WAY OF QPF OVER THE AREA...WITH REALLY NO CHANCE FOR BETTER MOISTURE TO ADVECT BACK IN BEFORE IT GETS HERE. ONLY SLIGHT DIFFERENCES EXIST BETWEEN MODELS WITH TIMING...WITH THE GFS/GEM A TOUCH QUICKER SHOWING IT MAINLY A DAYTIME SUNDAY EVENT...WITH THE ECMWF LINGERING THINGS INTO THE EVENING HOURS. THIS DISTURBANCE WILL USHER IN A REINFORCING SHOT OF NORTHWESTERLY WINDS...AND COOLER AIR - WHICH LOOKS TO MAINLY AFFECT THE OVERNIGHT HOURS AND QUICKLY SLIDE EAST. CURRENT FORECAST HIGHS ON SUNDAY ARE ONCE AGAIN IN THE 40S...WITH SUNDAY NIGHT/MONDAY AM LOWS IN THE MID 20S. MONDAY THROUGH WEDNESDAY...THE FORECAST REMAINS DRY...BUT WILL HAVE TO KEEP AN EYE ON A DISTURBANCE MOVING THROUGH TUESDAY. AT THIS POINT MODELS IN GOOD AGREEMENT KEEPING PRECIP TO THE N/NE OF THE CWA...BUT MAY SEE SOME TEMP ADJUSTMENTS FOR TUESDAY AS ANOTHER SHORT LIVED BATCH OF COOLER AIR MOVES THROUGH. TIMING OF ALL OF THIS IS THE MAIN QUESTION. HIGHS REMAIN GENERALLY IN THE 40S...WITH LOWS IN THE 20S. && .AVIATION...(FOR THE 00Z KGRI TAF THROUGH 00Z THURSDAY EVENING) ISSUED AT 556 PM CST WED JAN 8 2014 CEILINGS SHOULD START TO TANK TONIGHT AS STRATUS BUILDS DOWN OVER TIME. ANY FREEZING DRIZZLE SHOULD REMAIN SOUTH OF THE TERMINAL. SOME MODELS ARE INDICATING MORE VISIBILITY RESTRICTIONS THAN INDICATED IN THE FORECAST...BUT DISCOUNTING THE MORE PESSIMISTIC SOLUTIONS DUE TO RECENT INITIATION ERRORS. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ UPDATE...HEINLEIN SHORT TERM...FAY LONG TERM...ADO AVIATION...HEINLEIN
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
758 PM EST FRI JAN 10 2014 .SYNOPSIS... A DEVELOPING AREA OF LOW PRESSURE OVER THE CENTRAL U.S. THIS AFTERNOON WILL MOVE THROUGH THE GREAT LAKES TONIGHT WITH IT`S ASSOCIATED FRONTS BRINGING SIGNIFICANT PRECIPITATION TO THE REGION LATE TONIGHT THROUGH SATURDAY NIGHT. WHILE A BIT OF PATCHY FREEZING RAIN IS POSSIBLE EARLY SATURDAY ESPECIALLY EAST OF THE GREEN MOUNTAINS...THE MAJORITY OF THE PRECIPITATION WILL FALL AS RAIN. SUNDAY WILL TURN BREEZY AND COLDER WITH THE PASSAGE OF A COLD FRONT EARLY...WITH SCATTERED SNOW SHOWERS POSSIBLE ESPECIALLY ACROSS THE HIGHER TERRAIN. && .NEAR TERM /UNTIL 6 AM SATURDAY MORNING/... AS OF 620 PM EST FRIDAY...NO SIGNIFICANT ADJUSTMENTS TO THE FORECAST WITH THIS UPDATE AS GOING FORECAST LOOKS TO BE IN GOOD SHAPE. UNDER OVERCAST SKIES...CURRENT TEMPERATURES IN THE MID 20S TO JUST BELOW FREEZING ARE NOT LIKELY TO FALL ALL THAT MUCH. THESE WILL START TO CLIMB IN THE CHAMPLAIN VALLEY AS LOW- LEVEL WIND FIELDS STRENGTHEN MARKEDLY AFTER MIDNIGHT. I`LL BE MONITORING THE EVOLUTION OF THE LOW- LEVEL THERMAL PROFILES WITH REGARDS TO PRECIPITATION TYPE FOR THE OVERNIGHT PERIOD. CURRENT RAP ANALYSIS PLACES THE 925 MB 0C ISOTHERM ALONG THE NY STATE THRUWAY EASTWARD TO JUST NORTH OF SARATOGA SPRINGS TO BRATTLEBORO...WHICH MATCHES UP NICELY WITH LATEST NAM/WRF PROGS. EXPECTATION IS THAT ONCE THE LOW-LEVEL WINDS STRENGTHEN AFTER MIDNIGHT THAT WILL ALLOW FOR A STRONGER SURGE OF WARM ADVECTION...RESULTING IN COMPLETE MELTING TO FREEZING RAIN IN THE FREEZING RAIN ADVISORY AREAS AND COLD RAIN ELSEHWERE. LOWS TONIGHT IN THE 20S TO AROUND 30 LOOK GOOD AT THIS POINT. PREVIOUS NEAR-TERM DISCUSSION ISSUED AT 417 PM EST FOLLOWS... FORECAST REMAINS ON TRACK FOR AN ACTIVE PERIOD OF WEATHER THIS WEEKEND WITH THE PRIMARY THREATS INCLUDING ICY ROAD CONDITIONS EARLY SATURDAY MORNING FROM AREAS OF FREEZING RAIN...MAINLY EAST OF THE GREEN MOUNTAINS...FOLLOWED BY POTENTIAL ICE JAM FLOODING LATE SATURDAY THROUGH SUNDAY ACROSS MOST OF THE NORTH COUNTRY FROM MODERATE TO HEAVY RAIN...WARM TEMPS AND MELTING SNOW AND ICE. CONDITIONS START OUT FAIRLY TRANQUIL FOR THIS EVENING THROUGH THE FIRST HALF OF THE OVERNIGHT AS A WEAK SHORTWAVE TROUGH WHICH BROUGHT SOME LIGHT SNOW TO THE REGION TODAY SHIFTS EAST OFF THE EASTERN SEABOARD LEAVING GENERALLY CLOUDY SKIES AND MILD TEMPS IN THE 20S TO LOWER 30S. MEANWHILE UPSTREAM...A DEVELOPING AREA OF LOW PRESSURE OVER THE CENTRAL CONUS WILL DEEPEN AND SHIFT NORTHEAST INTO THE CENTRAL GREAT LAKES BY 12Z SATURDAY. THE ASSOCIATED WARM FRONT EXTENDED EASTWARD THROUGH THE OHIO RIVER VALLEY THIS AFTERNOON LIFTS NORTHWARD INTO THE NORTHEAST WITH INCREASING 850-700MB WARM AIR ADVECTION AND SOUTHERLY FLOW KEEPING MILD TEMPERATURES AROUND FOR THE OVERNIGHT HOURS. CURRENT TEMPS ARE EITHER BELOW OR RIGHT ABOUT FREEZING THIS AFTERNOON AND WILL DROP OFF SLIGHTLY THROUGH THE FIRST HALF OF THE NIGHT...BUT SLOWLY RISE TOWARDS DAWN. WHILE MOST OF THE REGION WILL WARM BACK ABOVE FREEZING BEFORE THE DEEP LAYER ASCENT AND OVERRUNNING PRECIP ASSOCIATED WITH THE APPROACHING WARM FRONT MOVES IN...AREAS EAST OF THE GREEN MOUNTAIN SPINE AS WELL AS SOUTHERN ESSEX COUNTY NEW YORK AND THE FAR NORTHERN CORNER OF THE SAINT LAWRENCE VALLEY IN MASSENA WILL LIKELY STAY LOCKED IN BELOW FREEZING. THAT SAID...A BRIEF 2-4 HOUR PERIOD OF FREEZING RAIN IS LIKELY IN THESE LOCATIONS AT THE ONSET OF PRECIP BEFORE A CHANGEOVER TO PLAIN RAIN AS SURFACE TEMPS RISE ABOVE FREEZING MID SATURDAY MORNING. ONLY EXPECTING A LIGHT GLAZE TO FORM WITH THE MAIN IMPACT BEING SLICK ROAD SURFACES ESPECIALLY ON SECONDARY AND UNTREATED ROADWAYS. A FREEZING RAIN ADVISORY HAS BEEN POSTED. && .SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/... AS OF 417 PM EST FRIDAY...BY MID-MORNING SATURDAY...SAY 10 AM OR SO...SURFACE TEMPS WARM RAPIDLY ABOVE FREEZING ACROSS THE ENTIRE AREA AS THE AFOREMENTIONED WARM FRONT LIFTS NORTH OF THE INTL BORDER AND A STRONG SOUTHERLY 925-850MB JET OF 50-70KTS MOVES IN. AT THE SAME TIME...A BRIEF PERIOD OF MID LEVEL DRYING OCCURS FROM 700-500MB IN THE WARM SECTOR SO WE MAY SEE A BREAK IN THE WIDESPREAD RAIN AROUND MID-DAY BEFORE THE BEST QG FORCING ARRIVES DURING THE AFTERNOON AND EARLY EVENING HOURS AHEAD OF A SURFACE COLD FRONT. PRECIPITABLE WATER VALUES RISE TO OVER 300% OF NORMAL FOR THIS TIME OF YEAR WITH AFTERNOON TEMPS RISING WELL INTO THE 40S WITH A FEW 50S POSSIBLE ALL SUPPORTING A PERIOD OF MODERATE TO BRIEFLY HEAVY RAINFALL SATURDAY AFTERNOON/EVENING...ESPECIALLY ACROSS CENTRAL AND SOUTHERN VERMONT. WITH MODERATE RAIN...RAPID WARMING AND SNOW MELT ON TOP OF FROZEN GROUND THE POTENTIAL FOR ICE JAMS AND STREET FLOODING INCREASES AND WILL BE THE MAIN THREAT FOR THIS EVENT. PLEASE REFER TO HYDRO SECTION BELOW FOR ALL THE DETAILS. SURFACE COLD FRONT SHIFTS THROUGH THE REGION SATURDAY NIGHT WITH RAIN ENDING FROM WEST TO EAST AS LOW PRESSURE SHIFTS NORTHEAST INTO THE CANADIAN MARITIMES BY SUNDAY MORNING. BEHIND THE FRONT THERMAL PROFILES SUPPORT A RAIN/SNOW MIX ACROSS NORTHERN NEW YORK LATE SATURDAY NIGHT AND INTO VERMONT SUNDAY MORNING WITH SOME LIGHT ACCUMULATIONS POSSIBLE ACROSS THE HIGHER TERRAIN. LOW-LEVELS DRY OUT RELATIVELY QUICKLY THOUGH WITH HIGH PRESSURE BUILDING IN FROM THE WEST SO DON`T EXPECT TO SEE MUCH PRECIP AROUND BY THE AFTERNOON/EVENING HOURS. WHILE HIGH PRESSURE BUILDS IN FOR SUNDAY NIGHT...FLOW ALOFT REMAINS OUT OF THE NORTHWEST SO WE`LL LIKELY REMAIN FAIRLY CLOUDY BUT MILD WITH TEMPS GENERALLY IN THE 20S. && .LONG TERM /MONDAY THROUGH FRIDAY/... AS OF 237 PM EST FRIDAY...ACTIVE WX PATTERN LIKELY TO CONTINUE INTO THE EARLY AND MIDDLE PORTIONS OF NEXT WEEK WITH GLOBAL MODELS CONTINUING THEIR DISCREPANCIES ON EASTWARD PROGRESSION OF MEAN CENTRAL CONUS UPPER MERIDIONAL TROUGH AND THE TRACK/INTENSITY OF A POTENTIAL SECONDARY STORM SYSTEM TUE/TUE NIGHT. AT THIS TIME I`LL LEAN MORE STRONGLY TOWARD THE SLOWER/DEEPER EURO/UKMET/HPC SOLUTIONS GIVEN GFS`S INHERENT BIAS TOWARD MORE PROGRESSIVE FLOW DURING HIGHLY AMPLIFIED UPPER FLOW REGIMES. THIS WOULD SUGGEST THAT AFTER A BRIEF RESPITE ON MONDAY WITH WEAK HIGH PRESSURE AND SEASONABLY MILD TEMPERATURES...A RETURN TO MORE INCLEMENT/RAINY WEATHER IS LOOKING MORE LIKELY BY TUESDAY AS RAPIDLY DEEPENING LOW PRESSURE TRACKS NORTHEAST FROM THE TENNESSEE RVR VALLEY ACROSS OR JUST WEST OF OUR AREA. QUICK MOVING NATURE OF SYSTEM AND POTENTIAL DRY SLOT WOULD LIKELY KEEP QPF WITHIN REASONABLE LEVELS...BUT WITH A PRONOUNCED WARM SURGE NORTHWARD ALONG THE EASTERN SEABOARD INTO NEW ENGLAND ADDITIONAL SNOWMELT/ICE MOVEMENT WOULD APPEAR QUITE POSSIBLE. BY TUESDAY NIGHT PCPN MAY TRANSITION BACK TO A PERIOD OF LIGHT SNOW/SHSN BEFORE ENDING OVERNIGHT UNDER FAIRLY ROBUST POST- FRONTAL COLD THERMAL ADVECTION. THEREAFTER...A GRADUAL RETURN TO MORE SEASONAL JANUARY WEATHER BY NEXT WED-FRI AS TEMPERATURES TREND COOLER WITH PERIODIC CHANCES FOR FLURRIES/LIGHT SHSN AS MEAN UPPER TROUGH SETTLES ACROSS THE REGION. TEMPERATURES WON`T BE EXCESSIVELY CHILLY GIVEN LIKELIHOOD OF CLOUDS SO LOOKING AT HIGHS TOPPING OUT IN THE 25 TO 35 RANGE AND OVERNIGHT LOWS GENERALLY FROM 15 TO 25. && .AVIATION /01Z SATURDAY THROUGH WEDNESDAY/... THROUGH 00Z SUNDAY...MOISTURE WILL SPREAD NORTHEAST INTO THE REGION FROM THE SOUTHEASTERN U.S. OVERNIGHT. EXPECTING A PERIOD OF FREEZING RAIN MAINLY AFTER 08Z SATURDAY AS SURFACE TEMPERATURES WILL BE AT OR BELOW FREEZING. HOWEVER...WARMER AIR WILL MOVE INTO THE REGION BY DAYBREAK ON SATURDAY...SO EXPECTING ANY POCKETS OF FREEZING RAIN TO CHANGE TO PLAIN RAIN BY 13Z SATURDAY...AS SURFACE TEMPERATURES CLIMB ABOVE FREEZING. EXPECTING CEILINGS TO LOWER TO MVFR OVERNIGHT AND BECOMING MAINLY IFR BY 15Z SATURDAY IN RAIN. ALSO...EXPECTING LOW LEVEL WIND SHEAR TO DEVELOP ACROSS THE REGION BY 13Z SATURDAY AND CONTINUE THROUGH 00Z SUNDAY. OUTLOOK 00Z SUNDAY THROUGH WEDNESDAY... 00Z SUNDAY THROUGH 12Z SUNDAY...MVFR/IFR AS STRONG LOW PRESSURE MOVING NORTHEAST THROUGH THE GREAT LAKES BRINGS WIDESPREAD RAINFALL TO THE REGION. 12Z SUNDAY THROUGH 00Z MONDAY...COLDER AIR RETURNS SUNDAY WITH ANY LINGERING PRECIP CHANGING OVER TO SCATTERED MVFR/IFR SNOW SHOWERS...MAINLY OVER THE HIGHER TERRAIN. 00Z MONDAY THROUGH 00Z TUESDAY...VFR UNDER HIGH PRESSURE. TUESDAY AND WEDNESDAY...MVFR/IFR CONDITIONS POSSIBLE IN RAIN AND SNOW SHOWERS. && .HYDROLOGY... AS OF 415 PM EST FRIDAY...A FLOOD WATCH REMAINS IN EFFECT FROM 21Z SATURDAY THROUGH 00Z MONDAY FOR MUCH OF THE AREA WITH THE EXCEPTION OF THE CHAMPLAIN ISLANDS AND THE ST. LAWRENCE VALLEY. MAIN THREAT THIS WEEKEND WILL BE POTENTIAL ICE JAM AND POOR DRAINAGE FLOODING AS TEMPERATURES WARM WELL INTO THE 40S SATURDAY AFTERNOON AND RAINFALL OF 0.5" TO OVER AN INCH...WITH THE HIGHEST AMOUNTS ACROSS SOUTH-CENTRAL VT AND PROGRESSIVELY LOWER TOWARD THE NW. MUCH OF THE RAINFALL WILL GO DIRECTLY INTO RUNOFF WITH FROZEN GROUND (6" FROST DEPTH AT BTV MEASURED AT 12Z WEDNESDAY) AND EXISTING SNOW/ICE COVER ACROSS THE REGION FOLLOWING PROLONGED COLD/BELOW NORMAL TEMPERATURE STRETCH PAST SEVERAL WEEKS. SOME MELTING SNOW AND ICE WILL ADD TO RUNOFF FROM RAINFALL. THE ANTICIPATED WARMUP AND RAINFALL WILL BE ENOUGH TO CAUSE ICE MOVEMENT AND POTENTIAL BREAKUP. THE SMALLER RIVERS AND STREAMS WILL BE THE MOST SUSCEPTIBLE WITH QUICKER RESPONSE TO RUNOFF AND THINNER ICE COVER. SMALLER RIVERS AND STREAMS SHOULD HAVE THE FIRST PROBLEMS BEGINNING LATE SATURDAY AFTERNOON INTO SATURDAY NIGHT. MAIN STEM RIVERS...ESPECIALLY FROM THE WINOOSKI SOUTH...COULD SEE PROBLEMS SATURDAY NIGHT AND WITH A POTENTIAL CREST SUNDAY. THESE SOUTHERN BASINS WILL SEE THE GREATEST RAINFALL AND WARMEST TEMPS SO ICE MOVEMENT SHOULD BE MOST PRONOUNCED ACROSS CENTRAL AND SOUTHERN VT. THAT SAID...CAN`T RULE OUT ISOLATED ICE JAM PROBLEMS FOR ALL OF NORTHERN VT AND IN THE ADIRONDACKS...ESPECIALLY ASSOCIATED WITH KNOWN EXISTING JAMS WHICH COULD SEE ADDITIONAL MOVEMENT ASSOCIATED WITH INCREASED STREAMFLOW/RIVER LEVELS SAT NIGHT AND SUNDAY. LOCAL STREET FLOODING IS ALSO LIKELY DUE TO ICE/SNOW COVERED DRAINS AND CULVERTS. TIMING FOR MINOR STREET FLOODING WOULD MAINLY BE SATURDAY AFTERNOON INTO SATURDAY NIGHT. && .MARINE... AS OF 300 PM EST FRIDAY...WINDY AND ROUGH TO HAZARDOUS CONDITIONS EXPECTED ON THE LAKE AS CHANNELED SOUTHERLY IN ADVANCE OF APPROACHING LOW PRESSURE CONTINUES WITH WIND SPEEDS OF 15 TO 25 KNOTS TONIGHT. WAVES WILL GENERALLY RANGE FROM 2 TO 3 FEET ACROSS THE BROAD LAKE. THE POTENTIAL FOR STRONG WINDS AND WAVES OF 3 TO 5 FEET WILL PERSIST INTO SATURDAY...WITH WARM TEMPERATURES AND RAINFALL INCREASING RUNOFF INTO THE LAKE. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...FREEZING RAIN ADVISORY FROM 4 AM TO 10 AM EST SATURDAY FOR VTZ003-004-006>008-010-012. FLOOD WATCH FROM SATURDAY AFTERNOON THROUGH SUNDAY EVENING FOR VTZ002>012-016>019. NY...FREEZING RAIN ADVISORY FROM 4 AM TO 10 AM EST SATURDAY FOR NYZ026-034. FLOOD WATCH FROM SATURDAY AFTERNOON THROUGH SUNDAY EVENING FOR NYZ028>031-034-035. && $$ SYNOPSIS...LAHIFF NEAR TERM...LAHIFF/LOCONTO SHORT TERM...LAHIFF LONG TERM...JMG AVIATION...JMG/WGH HYDROLOGY...WFO BTV MARINE...WFO BTV
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
620 PM EST FRI JAN 10 2014 .SYNOPSIS... A DEVELOPING AREA OF LOW PRESSURE OVER THE CENTRAL U.S. THIS AFTERNOON WILL MOVE THROUGH THE GREAT LAKES TONIGHT WITH IT`S ASSOCIATED FRONTS BRINGING SIGNIFICANT PRECIPITATION TO THE REGION LATE TONIGHT THROUGH SATURDAY NIGHT. WHILE A BIT OF PATCHY FREEZING RAIN IS POSSIBLE EARLY SATURDAY ESPECIALLY EAST OF THE GREEN MOUNTAINS...THE MAJORITY OF THE PRECIPITATION WILL FALL AS RAIN. SUNDAY WILL TURN BREEZY AND COLDER WITH THE PASSAGE OF A COLD FRONT EARLY...WITH SCATTERED SNOW SHOWERS POSSIBLE ESPECIALLY ACROSS THE HIGHER TERRAIN. && .NEAR TERM /UNTIL 6 AM SATURDAY MORNING/... AS OF 620 PM EST FRIDAY...NO SIGNIFICANT ADJUSTMENTS TO THE FORECAST WITH THIS UPDATE AS GOING FORECAST LOOKS TO BE IN GOOD SHAPE. UNDER OVERCAST SKIES...CURRENT TEMPERATURES IN THE MID 20S TO JUST BELOW FREEZING ARE NOT LIKELY TO FALL ALL THAT MUCH. THESE WILL START TO CLIMB IN THE CHAMPLAIN VALLEY AS LOW- LEVEL WIND FIELDS STRENGTHEN MARKEDLY AFTER MIDNIGHT. I`LL BE MONITORING THE EVOLUTION OF THE LOW- LEVEL THERMAL PROFILES WITH REGARDS TO PRECIPITATION TYPE FOR THE OVERNIGHT PERIOD. CURRENT RAP ANALYSIS PLACES THE 925 MB 0C ISOTHERM ALONG THE NY STATE THRUWAY EASTWARD TO JUST NORTH OF SARATOGA SPRINGS TO BRATTLEBORO...WHICH MATCHES UP NICELY WITH LATEST NAM/WRF PROGS. EXPECTATION IS THAT ONCE THE LOW-LEVEL WINDS STRENGTHEN AFTER MIDNIGHT THAT WILL ALLOW FOR A STRONGER SURGE OF WARM ADVECTION...RESULTING IN COMPLETE MELTING TO FREEZING RAIN IN THE FREEZING RAIN ADVISORY AREAS AND COLD RAIN ELSEHWERE. LOWS TONIGHT IN THE 20S TO AROUND 30 LOOK GOOD AT THIS POINT. PREVIOUS NEAR-TERM DISCUSSION ISSUED AT 417 PM EST FOLLOWS... FORECAST REMAINS ON TRACK FOR AN ACTIVE PERIOD OF WEATHER THIS WEEKEND WITH THE PRIMARY THREATS INCLUDING ICY ROAD CONDITIONS EARLY SATURDAY MORNING FROM AREAS OF FREEZING RAIN...MAINLY EAST OF THE GREEN MOUNTAINS...FOLLOWED BY POTENTIAL ICE JAM FLOODING LATE SATURDAY THROUGH SUNDAY ACROSS MOST OF THE NORTH COUNTRY FROM MODERATE TO HEAVY RAIN...WARM TEMPS AND MELTING SNOW AND ICE. CONDITIONS START OUT FAIRLY TRANQUIL FOR THIS EVENING THROUGH THE FIRST HALF OF THE OVERNIGHT AS A WEAK SHORTWAVE TROUGH WHICH BROUGHT SOME LIGHT SNOW TO THE REGION TODAY SHIFTS EAST OFF THE EASTERN SEABOARD LEAVING GENERALLY CLOUDY SKIES AND MILD TEMPS IN THE 20S TO LOWER 30S. MEANWHILE UPSTREAM...A DEVELOPING AREA OF LOW PRESSURE OVER THE CENTRAL CONUS WILL DEEPEN AND SHIFT NORTHEAST INTO THE CENTRAL GREAT LAKES BY 12Z SATURDAY. THE ASSOCIATED WARM FRONT EXTENDED EASTWARD THROUGH THE OHIO RIVER VALLEY THIS AFTERNOON LIFTS NORTHWARD INTO THE NORTHEAST WITH INCREASING 850-700MB WARM AIR ADVECTION AND SOUTHERLY FLOW KEEPING MILD TEMPERATURES AROUND FOR THE OVERNIGHT HOURS. CURRENT TEMPS ARE EITHER BELOW OR RIGHT ABOUT FREEZING THIS AFTERNOON AND WILL DROP OFF SLIGHTLY THROUGH THE FIRST HALF OF THE NIGHT...BUT SLOWLY RISE TOWARDS DAWN. WHILE MOST OF THE REGION WILL WARM BACK ABOVE FREEZING BEFORE THE DEEP LAYER ASCENT AND OVERRUNNING PRECIP ASSOCIATED WITH THE APPROACHING WARM FRONT MOVES IN...AREAS EAST OF THE GREEN MOUNTAIN SPINE AS WELL AS SOUTHERN ESSEX COUNTY NEW YORK AND THE FAR NORTHERN CORNER OF THE SAINT LAWRENCE VALLEY IN MASSENA WILL LIKELY STAY LOCKED IN BELOW FREEZING. THAT SAID...A BRIEF 2-4 HOUR PERIOD OF FREEZING RAIN IS LIKELY IN THESE LOCATIONS AT THE ONSET OF PRECIP BEFORE A CHANGEOVER TO PLAIN RAIN AS SURFACE TEMPS RISE ABOVE FREEZING MID SATURDAY MORNING. ONLY EXPECTING A LIGHT GLAZE TO FORM WITH THE MAIN IMPACT BEING SLICK ROAD SURFACES ESPECIALLY ON SECONDARY AND UNTREATED ROADWAYS. A FREEZING RAIN ADVISORY HAS BEEN POSTED. && .SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/... AS OF 417 PM EST FRIDAY...BY MID-MORNING SATURDAY...SAY 10 AM OR SO...SURFACE TEMPS WARM RAPIDLY ABOVE FREEZING ACROSS THE ENTIRE AREA AS THE AFOREMENTIONED WARM FRONT LIFTS NORTH OF THE INTL BORDER AND A STRONG SOUTHERLY 925-850MB JET OF 50-70KTS MOVES IN. AT THE SAME TIME...A BRIEF PERIOD OF MID LEVEL DRYING OCCURS FROM 700-500MB IN THE WARM SECTOR SO WE MAY SEE A BREAK IN THE WIDESPREAD RAIN AROUND MID-DAY BEFORE THE BEST QG FORCING ARRIVES DURING THE AFTERNOON AND EARLY EVENING HOURS AHEAD OF A SURFACE COLD FRONT. PRECIPITABLE WATER VALUES RISE TO OVER 300% OF NORMAL FOR THIS TIME OF YEAR WITH AFTERNOON TEMPS RISING WELL INTO THE 40S WITH A FEW 50S POSSIBLE ALL SUPPORTING A PERIOD OF MODERATE TO BRIEFLY HEAVY RAINFALL SATURDAY AFTERNOON/EVENING...ESPECIALLY ACROSS CENTRAL AND SOUTHERN VERMONT. WITH MODERATE RAIN...RAPID WARMING AND SNOW MELT ON TOP OF FROZEN GROUND THE POTENTIAL FOR ICE JAMS AND STREET FLOODING INCREASES AND WILL BE THE MAIN THREAT FOR THIS EVENT. PLEASE REFER TO HYDRO SECTION BELOW FOR ALL THE DETAILS. SURFACE COLD FRONT SHIFTS THROUGH THE REGION SATURDAY NIGHT WITH RAIN ENDING FROM WEST TO EAST AS LOW PRESSURE SHIFTS NORTHEAST INTO THE CANADIAN MARITIMES BY SUNDAY MORNING. BEHIND THE FRONT THERMAL PROFILES SUPPORT A RAIN/SNOW MIX ACROSS NORTHERN NEW YORK LATE SATURDAY NIGHT AND INTO VERMONT SUNDAY MORNING WITH SOME LIGHT ACCUMULATIONS POSSIBLE ACROSS THE HIGHER TERRAIN. LOW-LEVELS DRY OUT RELATIVELY QUICKLY THOUGH WITH HIGH PRESSURE BUILDING IN FROM THE WEST SO DON`T EXPECT TO SEE MUCH PRECIP AROUND BY THE AFTERNOON/EVENING HOURS. WHILE HIGH PRESSURE BUILDS IN FOR SUNDAY NIGHT...FLOW ALOFT REMAINS OUT OF THE NORTHWEST SO WE`LL LIKELY REMAIN FAIRLY CLOUDY BUT MILD WITH TEMPS GENERALLY IN THE 20S. && .LONG TERM /MONDAY THROUGH FRIDAY/... AS OF 237 PM EST FRIDAY...ACTIVE WX PATTERN LIKELY TO CONTINUE INTO THE EARLY AND MIDDLE PORTIONS OF NEXT WEEK WITH GLOBAL MODELS CONTINUING THEIR DISCREPANCIES ON EASTWARD PROGRESSION OF MEAN CENTRAL CONUS UPPER MERIDIONAL TROUGH AND THE TRACK/INTENSITY OF A POTENTIAL SECONDARY STORM SYSTEM TUE/TUE NIGHT. AT THIS TIME I`LL LEAN MORE STRONGLY TOWARD THE SLOWER/DEEPER EURO/UKMET/HPC SOLUTIONS GIVEN GFS`S INHERENT BIAS TOWARD MORE PROGRESSIVE FLOW DURING HIGHLY AMPLIFIED UPPER FLOW REGIMES. THIS WOULD SUGGEST THAT AFTER A BRIEF RESPITE ON MONDAY WITH WEAK HIGH PRESSURE AND SEASONABLY MILD TEMPERATURES...A RETURN TO MORE INCLEMENT/RAINY WEATHER IS LOOKING MORE LIKELY BY TUESDAY AS RAPIDLY DEEPENING LOW PRESSURE TRACKS NORTHEAST FROM THE TENNESSEE RVR VALLEY ACROSS OR JUST WEST OF OUR AREA. QUICK MOVING NATURE OF SYSTEM AND POTENTIAL DRY SLOT WOULD LIKELY KEEP QPF WITHIN REASONABLE LEVELS...BUT WITH A PRONOUNCED WARM SURGE NORTHWARD ALONG THE EASTERN SEABOARD INTO NEW ENGLAND ADDITIONAL SNOWMELT/ICE MOVEMENT WOULD APPEAR QUITE POSSIBLE. BY TUESDAY NIGHT PCPN MAY TRANSITION BACK TO A PERIOD OF LIGHT SNOW/SHSN BEFORE ENDING OVERNIGHT UNDER FAIRLY ROBUST POST- FRONTAL COLD THERMAL ADVECTION. THEREAFTER...A GRADUAL RETURN TO MORE SEASONAL JANUARY WEATHER BY NEXT WED-FRI AS TEMPERATURES TREND COOLER WITH PERIODIC CHANCES FOR FLURRIES/LIGHT SHSN AS MEAN UPPER TROUGH SETTLES ACROSS THE REGION. TEMPERATURES WON`T BE EXCESSIVELY CHILLY GIVEN LIKELIHOOD OF CLOUDS SO LOOKING AT HIGHS TOPPING OUT IN THE 25 TO 35 RANGE AND OVERNIGHT LOWS GENERALLY FROM 15 TO 25. && .AVIATION /23Z FRIDAY THROUGH WEDNESDAY/... THROUGH 18Z SATURDAY...WIDESPREAD MIX OF VFR/MVFR/IFR CIGS ACROSS THE REGION OVER THE NEXT 24 HOURS. SOME VFR CIGS EARLY (THRU 00Z)...BUT GRADUALLY LOWER TO MVFR/IFR AT ALL TERMINALS THEREAFTER AS LOW PRESSURE APPROACHES THE REGION FROM THE SW. PRECIPITATION ASSOCIATED WITH THIS SYSTEM TO GENERALLY ARRIVE AFTER 06Z AND WHILE SOME BRIEF POCKETS OF -FZRA ARE POSSIBLE EARLY...THIS WILL MAINLY BE A RAIN EVENT FROM 12Z ONWARD. WINDS SOUTH TO SOUTHEASTERLY (NORTHEASTERLY AT KMSS) FROM 5 TO 10 KTS...INCREASING AND OCCNLY GUSTY (MAINLY AT KBTV/KSLK/KRUT) AFTER 06Z. SOME LLWS CONCERNS ALSO POSSIBLE FROM 12Z ONWARD AS SOUTH/SOUTHWESTERLY LOW LEVEL JET FROM 40-50 KTS ACCOMPANIES MAIN PUSH OF PRECIPITATION. OUTLOOK 18Z SATURDAY THROUGH TUESDAY... 18Z SATURDAY THROUGH 12Z SUNDAY...MVFR/IFR AS STRONG LOW PRESSURE MOVING NORTHEAST THROUGH THE GREAT LAKES BRINGS WIDESPREAD RAINFALL TO THE REGION. 12Z SUNDAY THROUGH 00Z MONDAY...COLDER AIR RETURNS SUNDAY WITH ANY LINGERING PRECIP CHANGING OVER TO SCATTERED MVFR/IFR SNOW SHOWERS...MAINLY OVER THE HIGHER TERRAIN. 00Z MONDAY THROUGH 00Z TUESDAY...VFR UNDER HIGH PRESSURE. TUESDAY...MVFR CONDITIONS POSSIBLE IN SCATTERED RAIN SNOW SHOWERS AS A WEAK CLIPPER PASSES TO OUR NORTH. && .HYDROLOGY... AS OF 415 PM EST FRIDAY...A FLOOD WATCH REMAINS IN EFFECT FROM 21Z SATURDAY THROUGH 00Z MONDAY FOR MUCH OF THE AREA WITH THE EXCEPTION OF THE CHAMPLAIN ISLANDS AND THE ST. LAWRENCE VALLEY. MAIN THREAT THIS WEEKEND WILL BE POTENTIAL ICE JAM AND POOR DRAINAGE FLOODING AS TEMPERATURES WARM WELL INTO THE 40S SATURDAY AFTERNOON AND RAINFALL OF 0.5" TO OVER AN INCH...WITH THE HIGHEST AMOUNTS ACROSS SOUTH-CENTRAL VT AND PROGRESSIVELY LOWER TOWARD THE NW. MUCH OF THE RAINFALL WILL GO DIRECTLY INTO RUNOFF WITH FROZEN GROUND (6" FROST DEPTH AT BTV MEASURED AT 12Z WEDNESDAY) AND EXISTING SNOW/ICE COVER ACROSS THE REGION FOLLOWING PROLONGED COLD/BELOW NORMAL TEMPERATURE STRETCH PAST SEVERAL WEEKS. SOME MELTING SNOW AND ICE WILL ADD TO RUNOFF FROM RAINFALL. THE ANTICIPATED WARMUP AND RAINFALL WILL BE ENOUGH TO CAUSE ICE MOVEMENT AND POTENTIAL BREAKUP. THE SMALLER RIVERS AND STREAMS WILL BE THE MOST SUSCEPTIBLE WITH QUICKER RESPONSE TO RUNOFF AND THINNER ICE COVER. SMALLER RIVERS AND STREAMS SHOULD HAVE THE FIRST PROBLEMS BEGINNING LATE SATURDAY AFTERNOON INTO SATURDAY NIGHT. MAIN STEM RIVERS...ESPECIALLY FROM THE WINOOSKI SOUTH...COULD SEE PROBLEMS SATURDAY NIGHT AND WITH A POTENTIAL CREST SUNDAY. THESE SOUTHERN BASINS WILL SEE THE GREATEST RAINFALL AND WARMEST TEMPS SO ICE MOVEMENT SHOULD BE MOST PRONOUNCED ACROSS CENTRAL AND SOUTHERN VT. THAT SAID...CAN`T RULE OUT ISOLATED ICE JAM PROBLEMS FOR ALL OF NORTHERN VT AND IN THE ADIRONDACKS...ESPECIALLY ASSOCIATED WITH KNOWN EXISTING JAMS WHICH COULD SEE ADDITIONAL MOVEMENT ASSOCIATED WITH INCREASED STREAMFLOW/RIVER LEVELS SAT NIGHT AND SUNDAY. LOCAL STREET FLOODING IS ALSO LIKELY DUE TO ICE/SNOW COVERED DRAINS AND CULVERTS. TIMING FOR MINOR STREET FLOODING WOULD MAINLY BE SATURDAY AFTERNOON INTO SATURDAY NIGHT. && .MARINE... AS OF 300 PM EST FRIDAY...WINDY AND ROUGH TO HAZARDOUS CONDITIONS EXPECTED ON THE LAKE AS CHANNELED SOUTHERLY IN ADVANCE OF APPROACHING LOW PRESSURE CONTINUES WITH WIND SPEEDS OF 15 TO 25 KNOTS TONIGHT. WAVES WILL GENERALLY RANGE FROM 2 TO 3 FEET ACROSS THE BROAD LAKE. THE POTENTIAL FOR STRONG WINDS AND WAVES OF 3 TO 5 FEET WILL PERSIST INTO SATURDAY...WITH WARM TEMPERATURES AND RAINFALL INCREASING RUNOFF INTO THE LAKE. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...FREEZING RAIN ADVISORY FROM 4 AM TO 10 AM EST SATURDAY FOR VTZ003-004-006>008-010-012. FLOOD WATCH FROM SATURDAY AFTERNOON THROUGH SUNDAY EVENING FOR VTZ002>012-016>019. NY...FREEZING RAIN ADVISORY FROM 4 AM TO 10 AM EST SATURDAY FOR NYZ026-034. FLOOD WATCH FROM SATURDAY AFTERNOON THROUGH SUNDAY EVENING FOR NYZ028>031-034-035. && $$ SYNOPSIS...LAHIFF NEAR TERM...LAHIFF/LOCONTO SHORT TERM...LAHIFF LONG TERM...JMG AVIATION...JMG/KGM HYDROLOGY...WFO BTV MARINE...WFO BTV
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
630 AM EST THU JAN 9 2014 .SYNOPSIS... COLD HIGH PRESSURE WILL GRADUALLY SHIFT OFFSHORE TODAY. A COASTAL TROUGH ALONG THE GEORGIA COAST WILL SLOWLY LIFT NORTHWARD AS A WARM FRONT LATE FRIDAY INTO SATURDAY. MILDER AND UNSETTLED WEATHER IS EXPECTED THIS WEEKEND. A COLD FRONT WILL CROSS THE AREA LATE SATURDAY. DRIER AND MILD CONDITIONS ARE EXPECTED FOR EARLY NEXT WEEK. && .NEAR TERM /THROUGH TONIGHT/... AS OF 630 AM THURSDAY...WARM ADVECTION IS OCCURRING AS LOW AS 500 FEET ABOVE THE GROUND THIS MORNING WHERE EASTERLY WINDS ARE ADVECTING MODIFIED ATLANTIC AIR ONSHORE. ATLANTIC MOISTURE RIDING UP OVER THE RESIDUAL ARCTIC AIR AT THE SURFACE IS RESPONSIBLE FOR AN EXPANDING DECK OF STRATOCUMULUS CLOUDS ACROSS MOST OF SOUTH CAROLINA AND NOW SOUTHEASTERN NORTH CAROLINA. THIS AREA OF LIFT ALONG THE 285-290K ISENTROPIC SURFACES WAS SHOWN ON THE 00Z MODELS TO MAINLY AFFECT THE I-95 CORRIDOR AND POINTS WESTWARD TODAY...BUT SATELLITE TRENDS SHOW THIS LIFT IS CURRENTLY AIMED FARTHER EAST. THIS MASSIVELY COMPLICATES SKY COVER FORECASTS SINCE THE LIKELIHOOD OF CLOUDS PERSISTING ALL DAY ALONG THE COAST IS NOT ALL THAT GREAT. NEITHER THE 06Z NAM OR 06Z GFS HAVE A GOOD HANDLE ON CLOUDS...AND EVEN THE 10Z RUC SHOWS INSUFFICIENT MOISTURE TO ACCOUNT FOR ALL THE CLOUDS OBSERVED. WITH LOW CONFIDENCE I AM FORECASTING SKIES TO AVERAGE MOSTLY CLOUDY TODAY INLAND...AND VARIABLY CLOUDY ALONG THE COAST WITH AT LEAST ONE PERIOD OF PARTLY CLOUDY SKIES LATE THIS MORNING OR EARLY THIS AFTERNOON. THE OLD ARCTIC HIGH IS NOW NORTHEAST OF HATTERAS AND IS MOVING OUT TO SEA. A COASTAL TROUGH IS DEVELOPING ALONG THE GEORGIA AND NORTHERN FLORIDA COAST. THIS FEATURE WILL NOT APPRECIABLY STRENGTHEN TODAY OR TONIGHT...BUT WILL HELP TO VEER WINDS BETWEEN THE SURFACE AND 850 MB MORE SOUTHEASTERLY WITH TIME. 850 MB TEMPS CURRENTLY AROUND +2C SHOULD WARM TO +5C BY THIS EVENING...AND THEN TO +8C LATE TONIGHT. ASSUMING CLOUDS BEHAVE OUR HIGHS SHOULD REACH THE MID 50S ALONG THE COAST...AND AROUND 50 ALONG THE I-95 CORRIDOR. LOWS FOR TONIGHT ARE TRICKY ESPECIALLY IN THE WILMINGTON AREA WHERE EVEN AN HOUR OR TWO OF MOSTLY CLEAR SKIES COULD ALLOW STOUT RADIATIONAL COOLING TO WRECK OUR FORECAST. IF MOSTLY CLOUDY SKIES INHIBIT EFFICIENT RADIATIONAL COOLING THE ONSHORE WIND SHOULD HOLD LOWS IN THE LOW TO MID 40S ALONG THE COAST...WITH UPPER 30S INLAND. RAIN CHANCES APPEAR TO BE MAINLY CONFINED TO AREAS NEAR AND WEST OF I-95...AND ONLY 20-30 PERCENT TONIGHT AS THE DEEPEST MOISTURE AND BEST LIFT SHOOTS NORTH THROUGH CENTRAL SOUTH CAROLINA. ONE FINAL NOTE: TODAY MARKS THE POINT IN WILMINGTON WHERE THE DAILY NORMAL HIGHS AND LOWS REACH THE BOTTOM OF THEIR ANNUAL CURVES. THE RAW NCDC DATA SHOWS AVERAGES FOR TODAY OF 55.9/35.3 AND THOSE BEGIN TO TICK UPWARD ON JANUARY 13TH. BY THE END OF JANUARY THE NORMAL HIGH SHOULD BE UP BY 2 DEGREES WITH A ONE DEGREE RISE IN THE NORMAL LOW. && .SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/... AS OF 300 AM THURSDAY...MORE SIGNIFICANT WARMING HEADING INTO THE WEEKEND AS COASTAL TROUGH PUSHED INLAND AND THEN LIFTS FARTHER NORTH AS WARM FRONT BY LATE FRI WITH TEMPS RUNNING WELL ABOVE NORMAL...INTO THE 60S FRI AND 70S ON SATURDAY. LOOKS LIKE BEST LIFT ON FRI WILL REMAIN FARTHER INLAND RIDING OVER SHALLOW DENSER COLD AIR IN PLACE AND WILL SHOW BEST POPS THERE INITIALLY. BY SATURDAY WILL SEE MORE SIGNIFICANT QPF IN CONVECTION ASSOCIATED WITH COLD FRONT MOVING EAST THROUGH THE CAROLINAS. STILL LOOKS LIKE STRONG LLJ WILL DEVELOP WITH BETTER DYNAMICS ALOFT THROUGH SAT AFTN. LOOKS LIKE ALL WEATHER WILL CLEAR OUT OF THE AREA AS COLD FRONT MOVES OFF SHORE SAT NIGHT. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... AS OF 300 AM THURSDAY...HAVE TRENDED TOWARD DRIER FORECAST FOR EARLY NEXT WEEK WITH DRY AND MILD AIR TO FOLLOW COLD FRONT. COLD FRONT MOVES FARTHER OFF SHORE THROUGH SUNDAY AS HIGH PRESSURE BUILDS UP FROM THE GULF COAST OVER THE SOUTHEAST. THIS WILL LEAVE MODELS BEGIN TO DIVERGE COME MONDAY AS GFS IS MUCH QUICKER TO KICK HIGH PRESSURE OFF THE COAST ALLOWING FOR A WARMER MOISTER RETURN FLOW BY MONDAY MORNING. A DEEP SW FLOW SETS UP THROUGH MONDAY AS MID TO UPPER TROUGH DIGS DOWN THROUGH THE CENTRAL CONUS AMPLIFYING THE SW FLOW ALOFT INTO THE CAROLINAS SUNDAY NIGHT INTO MONDAY. THIS WILL ALLOW A SHORTWAVE TO TRACK UP FROM THE GULF ACROSS THE SOUTHEAST...BUT GFS KEEPS MAIN ENERGY ASSOCIATED WITH THIS SYSTEM TO OUR EAST THROUGH MONDAY NIGHT INTO TUES BRINGING A DRY COLD FRONT THROUGH BY TUES MORNING. THE OTHER MODELS TRACK THE DISTURBANCE UP IN THE SOUTHWEST FLOW RIGHT OVER LOCAL AREA BRINGING CLOUDY AND WET WEATHER THROUGH TUES BEFORE H5 TROUGH DIGS SOUTH PUSHING COLD FRONT IN FROM THE NORTHWEST TO CLEAR OUT ALL WEATHER ON WED. BY THURS HIGH PRESSURE SHOULD ONCE AGAIN ESTABLISH ITSELF ACROSS THE SOUTHEAST LEAVING DRIER AND COOLER WEATHER. OVERALL EXPECT DRY AND MILD WEATHER BEHIND COLD FRONT ON SUNDAY INTO MONDAY AS RIDGE QUICKLY BUILDS BACK UP THROUGH THE SOUTHEAST. TEMPS SHOULD REACH INTO THE 60S MOST PLACES SUN AND MONDAY. FOR NOW WILL KEEP WITH DRIER FORECAST FOR MON NIGHT INTO TUES WITH TEMPS CONTINUING TO RUN ABOVE NORMAL...WELL INTO THE 60S ON MONDAY AIDED BY WESTERLY DOWNSLOPE FLOW INTO TUES. BY WED GOING WITH DRY COLD FRONT MOVING THROUGH...LEAVING ALL WEATHER EAST OF LOCAL FORECAST AREA. EXPECT MORE SEASONABLE WEATHER THROUGH MID WEEK NEXT WEEK. && .AVIATION /12Z THURSDAY THROUGH MONDAY/... AS OF 12Z...SATELLITE IMAGERY AND SURFACE OBS INDICATE LOW CLOUDS 5-8KFT HAVE SPREAD ACROSS OUR CWA THIS MORNING. EXPECT VFR TO PERSIST TODAY WITH SCT/BKN LOW TO MID LEVEL CLOUDS AND NORTHEAST WINDS AOB 10 KTS. THE WINDS WILL BECOME MORE EASTERLY TONIGHT AS A DEVELOPING COASTAL TROUGH NEARS OUR COAST. RAIN CHANCES INCREASE SLIGHTLY LATE TONIGHT INTO EARLY FRIDAY AS MOIST ISENTROPIC LIFT MAY GENERATE -RA...ESPECIALLY INLAND. THEREFORE...HAVE INCLUDED VCSH FOR KFLO AND KLBT OVERNIGHT...WHILE THE COASTAL SITES SHOULD REMAIN DRY. MVFR CIGS COULD ALSO DEVELOP OVERNIGHT AS LOW LEVEL E-SE FLOW ADVECTS MARINE STRATOCU ONSHORE. EXTENDED OUTLOOK...MVFR CIGS WITH A CHANCE OF SHOWERS ON FRIDAY. SHOWERS LIKELY WITH MVFR/IFR CONDITIONS ON SATURDAY. VFR SUNDAY AND MONDAY. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 630 AM THURSDAY...ARCTIC HIGH PRESSURE IS LOCATED NORTHEAST OF HATTERAS THIS MORNING AND SHOULD CONTINUE TO MOVE AWAY FROM THE CAROLINAS TODAY. A COASTAL TROUGH ALONG THE NORTH FLORIDA/GEORGIA COAST WILL DRIFT A BIT WESTWARD TONIGHT...CAUSING A SLOW VEERING OF SURFACE WINDS ACROSS THE CAROLINA COASTAL WATERS. ANY REAL SHIFT TO WARM SOUTHEAST WINDS WILL LIKELY REMAIN ACROSS THE OFFSHORE WATERS AT LEAST THROUGH TONIGHT...WITH MORE OF A NORTHEAST TO EAST WIND EXPECTED WITHIN 20 MILES OF SHORE. WIND SPEEDS THIS MORNING ARE 10-15 KNOTS WITH GUSTS OUT AT THE FRYING PAN SHOALS BUOY AS HIGH AS 16 KNOTS. WINDS SHOULD INCREASE A FEW MORE KNOTS DURING THE DAY...PEAKING EARLY THIS EVENING AT 14-18 KNOTS BEFORE DIMINISHING A LITTLE OVERNIGHT. SEAS CURRENTLY 2-3 FEET WILL RESPOND TO THE INCREASING ONSHORE FETCH BEHIND THE DEPARTING HIGH...AND SHOULD BUILD TO 3-5 FEET TONIGHT. THERE IS SOME POTENTIAL FOR 6-FOOT SEAS TO DEVELOP NEAR 20 MILES DISTANCE FROM SHORE... PARTICULARLY EAST OF GEORGETOWN AND ALSO SOUTHEAST OF CAPE FEAR. IF THIS THREAT BECOMES MORE SIGNIFICANT WE MAY NEED TO RAISE A SMALL CRAFT ADVISORY FOR PORTIONS OF THE COASTAL WATERS. SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/... AS OF 300 AM THURSDAY...WINDS WILL VEER THROUGH THE PERIOD AS COASTAL TROUGH PUSHES INLAND ON FRI AND THEN SHIFTS FARTHER NORTH AS WARM FRONT THROUGH SATURDAY LEAVING AN INCREASING SOUTHERLY FLOW AHEAD OF AN APPROACHING COLD FRONT ON SATURDAY. OVERALL EXPECT LIGHTER ON SHORE FLOW TO BEGIN WITH WITH INCREASING SOUTHERLY WINDS THROUGH SATURDAY. WINDS 10-15 KTS THROUGH FRIDAY WILL INCREASE UP TO 15-20 KTS THROUGH EARLY SATURDAY AND WILL FURTHER INCREASE UP TO 25 KTS THROUGH SATURDAY. INCREASING ON SHORE FETCH AND SOUTHERLY PUSH ON SATURDAY WILL RAISE SEAS FROM TO 3-5 FT EARLY FRIDAY UP INTO SCA THRESHOLDS BY SATURDAY AHEAD OF APPROACHING COLD FRONT. WNA SHOWS SEAS UP TO 7 TO 9 FT BY SAT AFTN JUST AHEAD OF COLD FRONT. OFF SHORE FLOW BEHIND FRONT WILL KNOCK NEAR SHORE SEAS DOWN RAPIDLY DROPPING BELOW SCA CRITERIA FOR ALL WATERS BY SUNDAY MORNING. LONG TERM /SUNDAY THROUGH MONDAY/... AS OF 300 AM THURSDAY...A DECREASING OFF SHORE FLOW WILL CONTINUE ON SUNDAY AS HIGH PRESSURE BUILDS UP FROM THE GULF BEHIND EXITING COLD FRONT. EXPECT SEAS TO CONTINUE TO SUBSIDE IN SW TO W FLOW THROUGH SUNDAY DOWN LESS THAN 4 FT MOST WATERS. THE OFFSHORE FLOW WILL KEEP SEAS IN THE 2-4 FEET RANGE MOST WATERS THROUGH EARLY. HIGH PRESSURE QUICKLY SHIFTS OVER THE WATERS ON SUNDAY MOVING OFF THE SOUTHEAST COAST SOUTH OF THE LOCAL WATERS BY LATE SUNDAY. THEREFORE EXPECT A RETURN FLOW UP TO 15 KTS THROUGH MONDAY. INCREASING SLIGHTLY AS DRY COLD FRONT MOVES TOWARD WATERS FROM THE WEST. WINDS WILL CONTINUE TO VEER AS THIS FRONT MOVES THROUGH WATERS MON NIGHT. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ NEAR TERM...TRA SHORT TERM...RGZ LONG TERM...RGZ AVIATION...BJR
AREA FORECAST DISCUSSION
NWS BISMARCK ND
938 PM CST FRI JAN 10 2014 .UPDATE... ISSUED AT 924 PM CST FRI JAN 10 2014 LATE EVENING UPDATE MAINLY FOR TEMPERATURES AND SKY COVER. THE RAP IS HANDLING THE PROGRESSION OF THE LOW CLOUDS ACROSS THE FORECAST AREA LATE THIS EVENING...AND HAVE FAVORED THAT MODEL FOR OVERNIGHT TRENDS. THIS NECESSITATED SOME ADJUSTMENTS TO OVERNIGHT TEMPS...WITH COLDEST READINGS NOW EXPECTED ACROSS THE WEST...WHILE MUCH OF THE EASTERN PORTION OF THE FORECAST AREA SHOULD BE WARMER THAN PREVIOUSLY EXPECTED. HAVE ALSO MAINTAINED SOME PATCHY LIGHT FREEZING DRIZZLE/FLURRIES NORTH CENTRAL INTO THE NORTHERN JAMES RIVER VALLEY THROUGH LATE EVENING...ALTHOUGH LITTLE OR NO IMPACT TO TRAVEL IS EXPECTED. && .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 352 PM CST FRI JAN 10 2014 FORECAST CHALLENGE WILL BE FOUND NEAR THE END OF THE SHORT TERM PERIOD AS A WARM FRONT APPROACHES THE WEST SATURDAY AFTERNOON. THIS WILL BRING A CHANCE FOR A WINTRY MIX ACROSS NORTHWEST NORTH DAKOTA SATURDAY AFTERNOON. TONIGHT...A WEAK TROUGH OF LOW PRESSURE MOVING EAST ALONG THE CANADIAN BORDER WILL PULL SOME COOLER AIR AND CLOUDS THROUGH THE NORTH CENTRAL AND INTO THE JAMES RIVER VALLEY TONIGHT. CURRENT MODEL AND SURFACE OBSERVATION TRENDS SUGGEST THE PRECIPITATION WILL REMAIN ALONG THE CANADIAN BORDER FRIDAY AFTERNOON. ON SATURDAY...THE WARM FRONT APPROACHES THE STATE FROM THE WEST. MODEL SOUNDINGS CONFIRM STRONG WINDS ABOVE THE SURFACE IN A WARM ADVECTION FIELD. DO NOT SEE AN EFFICIENT TRANSFER OF MOMENTUM TO THE SURFACE WITH THE INITIAL WARM ADVECTION SURGE. AS A RESULT THERE WILL BE SOME POTENTIAL FOR A WINTRY MIX NORTHWEST AS THE COLD AIR ONLY SLOWLY SCOURS OUT. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 352 PM CST FRI JAN 10 2014 THE MAIN HIGHLIGHTS IN THE EXTENDED PERIOD WILL BE A CHANCE OF MIXED PRECIPITATION SATURDAY NIGHT...POTENTIAL FOR WIND HAZARDS SUNDAY...THEN FOLLOWED BY TWO MORE CLIPPER SYSTEMS...MONDAY INTO MONDAY NIGHT...AND AGAIN WEDNESDAY NIGHT INTO THURSDAY. ON SATURDAY A CLIPPER SYSTEM TRACKS ACROSS ALBERTA INTO SASKATCHEWAN THEN INTO MANITOBA LATE SATURDAY NIGHT. WARM ADVECTION AHEAD OF THE SURFACE CYCLONE WILL INCREASE TEMPERATURES ABOVE THE SURFACE WELL ABOVE FREEZING. IT REMAINS TO BE SEEN HOW SURFACE TEMPERATURES WILL REACT...BUT IT APPEARS THE SOUTHWEST QUARTER OF NORTH DAKOTA WILL REMAIN ABOVE 32F FOR MUCH OF SATURDAY NIGHT...COLDER ELSEWHERE. BY 00 UTC SUNDAY MODELS BRING WARM ADVECTION PRECIPITATION INTO NORTHWEST NORTH DAKOTA...WITH PRECIPITATION THEN DEVELOPING EAST AND SOUTH ACROSS CENTRAL INTO SOUTHEASTERN NORTH DAKOTA THROUGH SAT NIGHT IN RESPONSE TO SHORTWAVE ENERGY TRAVERSING THE FORECAST AREA. BEING IN THE DRY SECTOR OF THE SURFACE SYSTEM TO OUR NORTH...PRECIPITATION AMOUNTS ARE EXPECTED TO BE LIGHT. HOWEVER...WITH NO STRONG COLD ADVECTION BEHIND THE CYCLONE...TEMPERATURES ALOFT WILL REMAIN ABOVE FREEZING THROUGH SATURDAY NIGHT. CURRENT GUIDANCE SUGGESTS THAT SFC AIR TEMPERATURES WILL REMAIN BELOW FREEZING...ESPECIALLY ALONG AND EAST OF THE HIGHWAY 83 CORRIDOR. COUPLED WITH WELL ABOVE FREEZING TEMPS ALOFT...THERE IS AN INCREASING POSSIBILITY OF FREEZING RAIN SATURDAY NIGHT...ESPECIALLY FROM THE MISSOURI RIVER IN SOUTH CENTRAL ND EAST INTO THE JAMES RIVER VALLEY. COLD ADVECTION BEHIND THE CLIPPER ARRIVES ON SUNDAY AS THE LOW TRACKS EAST INTO ONTARIO DRAGGING A COLD FRONT SOUTHEAST THROUGH THE REGION. WINDS WILL APPROACH 30 KNOTS WITH BOUNDARY LAYER WINDS DEPICTED TO BE NEAR 40KTS. A WIND ADVISORY MAY STILL BE NEEDED FOR PORTIONS OF THE AREA ON SUNDAY AFTERNOON/EVENING. WHILE OUR SNOW COVER WILL LIKELY BE CRUSTED OVER...THERE IS A SMALL CHANCE OF LOCALIZED BLOWING SNOW IN OPEN LOCATIONS. DID NOT MENTION BLOWING SNOW IN THE FORECAST WITH THIS ISSUANCE. WE OPTED TO HIGHLIGHT THE FREEZING RAIN AND WIND POTENTIAL IN A SPECIAL WEATHER STATEMENT. ANOTHER BREEZY TO WINDY PERIOD WILL BE IN STORE MONDAY AND MONDAY NIGHT AS THE NEXT CLIPPER MOVES THROUGH THE DAKOTAS. PERHAPS NOT AS STRONG AS SUNDAYS WINDS IT APPEARS. MODELS DO INDICATE A BETTER SHOT OF MOISTURE...MAINLY IN THE FORM OF LIGHT SNOW...ACROSS THE CWA. WILL MONITOR THIS OVER THE NEXT FEW FORECAST CYCLES. LATE IN THE FORECAST PERIOD...ANOTHER CLIPPER TRACKS ACROSS SOUTHERN CANADA...THIS TIME WITH A MUCH STRONGER MID LEVEL TROUGH. WE STILL LOOK TO REMAIN IN THE DRY SECTOR SO AT THIS TIME IT APPEARS ANY PRECIPITATION WILL BE MINIMAL. THE BIGGEST CONCERN WITH THIS FEATURE IS THE POTENTIAL FOR YET ANOTHER ROUND OF STRONG WINDS WEDNESDAY AFTERNOON THROUGH THURSDAY MORNING. CURRENT GUIDANCE (12Z GFS/ECMWF) ARE HINTING AT MID TO HIGH ADVISORY LEVEL WINDS TO NEAR WARNING CRITERIA. WILL ALSO BE MONITORING MODEL TRENDS REGARDING THIS FEATURE OVER THE NEXT FEW DAYS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 924 PM CST FRI JAN 10 2014 THE RAP IS MODELING LOW LEVEL IFR/MVFR CLOUD DECK MOVING THROUGH NORTH DAKOTA LATE THIS EVENING. LOW CLOUDS ARE SKIRTING KBIS...AND WILL MOVE INTO KJMS SHORTLY. THE RAP IS ALSO INDICATING A SECONDARY BATCH OF LOW LEVEL MOISTURE LATE TONIGHT INTO SATURDAY MORNING...MAINLY IMPACTING KMOT/KJMS AND POSSIBLY KBIS. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE/AVIATION...RP KINNEY SHORT TERM...WAA LONG TERM...NH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
721 PM CST FRI JAN 10 2014 .UPDATE... ISSUED AT 716 PM CST FRI JAN 10 2014 UPDATE MAINLY TO ADD FLURRIES/PATCHY LIGHT FREEZING DRIZZLE ACROSS THE NORTH THIS EVENING. FORECAST SOUNDINGS...OBS...AND MINOT RADAR INDICATE POTENTIAL FOR A FEW FLURRIES OR SOME PATCHY LIGHT FREEZING DRIZZLE ASSOCIATED WITH A LOW CLOUD DECK MOVING THROUGH THE NORTH THIS EVENING. MAJOR TRAVEL ISSUES NOT EXPECTED...BUT SOME ROADS REMAIN SLICK FROM PREVIOUS PRECIPITATION AND RE-FREEZING. && .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 352 PM CST FRI JAN 10 2014 FORECAST CHALLENGE WILL BE FOUND NEAR THE END OF THE SHORT TERM PERIOD AS A WARM FRONT APPROACHES THE WEST SATURDAY AFTERNOON. THIS WILL BRING A CHANCE FOR A WINTRY MIX ACROSS NORTHWEST NORTH DAKOTA SATURDAY AFTERNOON. TONIGHT...A WEAK TROUGH OF LOW PRESSURE MOVING EAST ALONG THE CANADIAN BORDER WILL PULL SOME COOLER AIR AND CLOUDS THROUGH THE NORTH CENTRAL AND INTO THE JAMES RIVER VALLEY TONIGHT. CURRENT MODEL AND SURFACE OBSERVATION TRENDS SUGGEST THE PRECIPITATION WILL REMAIN ALONG THE CANADIAN BORDER FRIDAY AFTERNOON. ON SATURDAY...THE WARM FRONT APPROACHES THE STATE FROM THE WEST. MODEL SOUNDINGS CONFIRM STRONG WINDS ABOVE THE SURFACE IN A WARM ADVECTION FIELD. DO NOT SEE AN EFFICIENT TRANSFER OF MOMENTUM TO THE SURFACE WITH THE INITIAL WARM ADVECTION SURGE. AS A RESULT THERE WILL BE SOME POTENTIAL FOR A WINTRY MIX NORTHWEST AS THE COLD AIR ONLY SLOWLY SCOURS OUT. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 352 PM CST FRI JAN 10 2014 THE MAIN HIGHLIGHTS IN THE EXTENDED PERIOD WILL BE A CHANCE OF MIXED PRECIPITATION SATURDAY NIGHT...POTENTIAL FOR WIND HAZARDS SUNDAY...THEN FOLLOWED BY TWO MORE CLIPPER SYSTEMS...MONDAY INTO MONDAY NIGHT...AND AGAIN WEDNESDAY NIGHT INTO THURSDAY. ON SATURDAY A CLIPPER SYSTEM TRACKS ACROSS ALBERTA INTO SASKATCHEWAN THEN INTO MANITOBA LATE SATURDAY NIGHT. WARM ADVECTION AHEAD OF THE SURFACE CYCLONE WILL INCREASE TEMPERATURES ABOVE THE SURFACE WELL ABOVE FREEZING. IT REMAINS TO BE SEEN HOW SURFACE TEMPERATURES WILL REACT...BUT IT APPEARS THE SOUTHWEST QUARTER OF NORTH DAKOTA WILL REMAIN ABOVE 32F FOR MUCH OF SATURDAY NIGHT...COLDER ELSEWHERE. BY 00 UTC SUNDAY MODELS BRING WARM ADVECTION PRECIPITATION INTO NORTHWEST NORTH DAKOTA...WITH PRECIPITATION THEN DEVELOPING EAST AND SOUTH ACROSS CENTRAL INTO SOUTHEASTERN NORTH DAKOTA THROUGH SAT NIGHT IN RESPONSE TO SHORTWAVE ENERGY TRAVERSING THE FORECAST AREA. BEING IN THE DRY SECTOR OF THE SURFACE SYSTEM TO OUR NORTH...PRECIPITATION AMOUNTS ARE EXPECTED TO BE LIGHT. HOWEVER...WITH NO STRONG COLD ADVECTION BEHIND THE CYCLONE...TEMPERATURES ALOFT WILL REMAIN ABOVE FREEZING THROUGH SATURDAY NIGHT. CURRENT GUIDANCE SUGGESTS THAT SFC AIR TEMPERATURES WILL REMAIN BELOW FREEZING...ESPECIALLY ALONG AND EAST OF THE HIGHWAY 83 CORRIDOR. COUPLED WITH WELL ABOVE FREEZING TEMPS ALOFT...THERE IS AN INCREASING POSSIBILITY OF FREEZING RAIN SATURDAY NIGHT...ESPECIALLY FROM THE MISSOURI RIVER IN SOUTH CENTRAL ND EAST INTO THE JAMES RIVER VALLEY. COLD ADVECTION BEHIND THE CLIPPER ARRIVES ON SUNDAY AS THE LOW TRACKS EAST INTO ONTARIO DRAGGING A COLD FRONT SOUTHEAST THROUGH THE REGION. WINDS WILL APPROACH 30 KNOTS WITH BOUNDARY LAYER WINDS DEPICTED TO BE NEAR 40KTS. A WIND ADVISORY MAY STILL BE NEEDED FOR PORTIONS OF THE AREA ON SUNDAY AFTERNOON/EVENING. WHILE OUR SNOW COVER WILL LIKELY BE CRUSTED OVER...THERE IS A SMALL CHANCE OF LOCALIZED BLOWING SNOW IN OPEN LOCATIONS. DID NOT MENTION BLOWING SNOW IN THE FORECAST WITH THIS ISSUANCE. WE OPTED TO HIGHLIGHT THE FREEZING RAIN AND WIND POTENTIAL IN A SPECIAL WEATHER STATEMENT. ANOTHER BREEZY TO WINDY PERIOD WILL BE IN STORE MONDAY AND MONDAY NIGHT AS THE NEXT CLIPPER MOVES THROUGH THE DAKOTAS. PERHAPS NOT AS STRONG AS SUNDAYS WINDS IT APPEARS. MODELS DO INDICATE A BETTER SHOT OF MOISTURE...MAINLY IN THE FORM OF LIGHT SNOW...ACROSS THE CWA. WILL MONITOR THIS OVER THE NEXT FEW FORECAST CYCLES. LATE IN THE FORECAST PERIOD...ANOTHER CLIPPER TRACKS ACROSS SOUTHERN CANADA...THIS TIME WITH A MUCH STRONGER MID LEVEL TROUGH. WE STILL LOOK TO REMAIN IN THE DRY SECTOR SO AT THIS TIME IT APPEARS ANY PRECIPITATION WILL BE MINIMAL. THE BIGGEST CONCERN WITH THIS FEATURE IS THE POTENTIAL FOR YET ANOTHER ROUND OF STRONG WINDS WEDNESDAY AFTERNOON THROUGH THURSDAY MORNING. CURRENT GUIDANCE (12Z GFS/ECMWF) ARE HINTING AT MID TO HIGH ADVISORY LEVEL WINDS TO NEAR WARNING CRITERIA. WILL ALSO BE MONITORING MODEL TRENDS REGARDING THIS FEATURE OVER THE NEXT FEW DAYS. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING) ISSUED AT 716 PM CST FRI JAN 10 2014 THE RAP IS MODELING LOW LEVEL IFR/MVFR CLOUD DECK MOVING THROUGH NORTH DAKOTA THIS EVENING...AND WILL HAVE TO MONITOR TRENDS FOR POSSIBLE INCLUSION IN KBIS TAF...IN ADDITION TO KMOT/KJMS. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE/AVIATION...RP KINNEY SHORT TERM...WAA LONG TERM...NH
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
627 PM CST FRI JAN 10 2014 .UPDATE... ISSUED AT 627 PM CST FRI JAN 10 2014 WATER VAPOR IMAGERY INDICATES UPPER CIRCULATION JUST NORTH OF HALLOCK...AND WILL CONTINUE TO PROPAGATE EASTWARD OVERNIGHT. SATELLITE IMAGERY INDICATES A CLEAR AREA WITHIN SOUTHERLY FLOW IN WARM SECTOR OF THIS SYSTEM. CLOUDS ACROSS THE FAR EASTERN FA HAVE STALLED WITH SUNSET...AND CLOUDS BEHIND THE WEAK COLD FRONT ARE MOVING INTO THE REGION QUICKER THAN EXPECTED. RAP GUIDANCE INDICATES THAT THE LOW CLOUDS ASSOCIATED WITH THE COLD AIR ADVECTION WILL ADVECT INTO THE ENTIRE FA BY MIDNIGHT (WHICH MAKES SENSE GIVEN CURRENT CONDITIONS). ACROSS THE FAR EASTERN FA...LOWER VSBY (LIKELY DUE TO FOG) REMAIN...AND RAP GUIDANCE SUGGESTS THESE CONDITIONS WILL CONTINUE UNTIL AROUND MIDNIGHT WHEN WINDS FINALLY SHIFT TO THE WEST/NORTHWEST. UPDATED THE GRIDS TO THE ABOVE THINKING. && .SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT) ISSUED AT 320 PM CST FRI JAN 10 2014 FORECAST CHALLENGE CONCERNS MAINLY TEMPERATURES AND LOW END PCPN CHANCES. MODELS IN FAIR AGREEMENT THROUGH THE PERIOD AND WILL USE BLEND FOR FORECAST. FOR TONIGHT COULD SEE SOME WRAP AROUND CLOUDS ACROSS THE NORTH AS SURFACE LOW TRACKS ACROSS FAR SOUTHERN CANADA. OTHERWISE SHOULD SEE FAIRLY CLEAR SKIES. WITH WEAK COLD ADVECTION TEMPERATURES MAY BE A BIT COOLER BUT THERE WILL BE SOME LIGHT MIXING. SURFACE RIDGE AXIS SHIFTS ACROSS FA ON SATURDAY. WARM ADVECTION GETS GOING FROM THE VALLEY WEST DURING THE AFTERNOON. TEMPERATURES OVERALL SHOULD REMAIN ON THE MILD SIDE IN THE 20S. WARM ADVECTION CONTINUES SATURDAY NIGHT ALLOWING TEMPERATURES TO AT THE LEAST HOLD STEADY. MODELS DIFFER ON PCPN POTENTIAL IN WARM ADVECTION ZONE. WITH WARM LAYER DEVELOPING ALOFT COULD SEE A MIX/ OR PATCHY ZR AND THIS WILL NEED TO BE MONITORED. GEM/ECMWF MOST BULLISH WITH PCPN POTENTIAL AND IF VERIFIES COULD SEE SOME SLIPPERY AREAS. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 320 PM CST FRI JAN 10 2014 WITH WESTERLY FLOW AND COOLING NOT TIL AFTERNOON TEMPERATURES SUNDAY SHOULD BE ABLE TO GET CLOSE TO IF NOT ABOVE FREEZING. FAIRLY GOOD/QUICK SHOT OF COLD ADVECTION BEHIND COLD FRONT SUNDAY NIGHT SHOULD DROP TEMPERATURES BACK CLOSER TO AVERAGE. COLUMN BEGINS TO RECOVER MONDAY WITH WARM ADVECTION -SN POSSIBLE. TEMPERATURE TREND SHOULD CONTINUE AT OR ABOVE AVERAGE. A NW FLOW PATTERN WILL DOMINATE AT THE BEGINNING OF THIS PERIOD...WITH A SERIES OF SHORTWAVE TROUGHS IMPACTING THE FCST AREA. HOWEVER...NO SIGNIFICANT PRECIP IS ANTICIPATED DURING THIS TIME. SHORTWAVE ENERGY DROPPING SOUTHEAST MON NIGHT WILL PROVIDE A LOW CHANCE OPPORTUNITY FOR LIGHT SNOW. THE SHORTWAVE TROUGH WILL ALSO REINFORCE THE COOLER AIR FOR TUESDAY. 5H HEIGHTS WILL BRIEFLY BUILD AHEAD OF THE NEXT SHORTWAVE TUE/TUE NIGHT. WITH THIS WAVE DIGGING SOUTHEAST...HEIGHTS WILL THEN FALL DURING THE DAY WED. THE SFC LOW WILL SLIDE SOUTHEAST ACROSS MANITOBA PUTTING THE AREA IN MILD WEST TO SOUTHWEST SFC FLOW FOR WED. THE ECMWF IS A BIT FARTHER NORTH THAN THE GFS WITH THE SFC LOW WED/WED NIGHT THOUGH BOTH MODELS BRING LIGHT PRECIP ACROSS NORTHERN MN DURING THIS PERIOD. A FAIRLY TIGHT PRESSURE GRADIENT WILL SETUP WED NIGHT INTO THU WITH GUSTY NORTHWEST WINDS BEHIND THE WAVE. WILL UP THE WINDS FROM MODEL GUIDANCE DURING THIS PERIOD. ANOTHER SHORTWAVE WILL DROP SOUTH IN THE MEAN UPPER TROF FRIDAY BRINGING ANOTHER SHOT OF COLD AIR. AS A RESULT TEMPS FRI WILL BE BACK DOWN INTO THE TEENS. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING) ISSUED AT 627 PM CST FRI JAN 10 2014 LIFR CONDITIONS WILL LIKELY REMAIN AT KBJI THROUGH THE OVERNIGHT HOURS...AND NOT SURE WHEN IMPROVEMENT COULD OCCUR. BRIEF IMPROVEMENT THIS EVENING IS POSSIBLE...BUT WOULD NOT LAST TOO LONG. AN AREA OF MVFR CIGS WILL AFFECT THE OTHER TAF SITES BY MIDNIGHT (AS WINDS BECOME WEST/NORTHWEST)...AND CONTINUE THROUGH MUCH OF THE OVERNIGHT HOURS. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ UPDATE...TG SHORT TERM...VOELKER LONG TERM...FRAZIER/VOELKER AVIATION...TG
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
305 AM CST THU JAN 9 2014 .SHORT TERM...(TODAY THROUGH FRIDAY) ISSUED AT 305 AM CST THU JAN 9 2014 BLOWING SNOW EARLY THIS MORNING AND THEN TEMPERATURES WILL BE THE MAIN FORECAST CONCERNS. THE FLOW HAS TRANSITIONED TO MORE ZONAL IN NATURE AND A TROUGH OF LOW PRESSURE DEVELOPING OVER THE NORTHERN ROCKIES HAS BROUGHT A FAIRLY TIGHT PRESSURE GRADIENT TO THE CWA THIS MORNING. SOUTHERLY WINDS HAVE PICKED UP INTO THE 20 TO 30 MPH RANGE...AND A WEAK SHORTWAVE MOVING THROUGH HAS BROUGHT A FEW FLURRIES/LIGHT SNOW SHOWERS TO THE NORTHERN RED RIVER VALLEY. THINK THAT FALLING SNOW WILL BE PRETTY INSIGNIFICANT SO KEPT POPS AT 20 PERCENT FOR TODAY. HOWEVER...THE WINDS HAVE BROUGHT VIS DOWN TO 1 TO 2 MILES IN SOME SPOTS THIS MORNING. ADDED A MENTION OF BLOWING SNOW IN THE GRIDS FOR OUR NORTH CENTRAL COUNTIES UNTIL WINDS BEGIN TO DECREASE A BIT LATER THIS MORNING AS THE SFC TROUGH AXIS MOVES EAST. THE SOUTHERLY WINDS AND INCREASING CLOUD COVER HAVE BROUGHT RISING TEMPS...WITH MOST LOCATIONS ABOVE ZERO AT THIS POINT. WIND CHILL VALUES ARE HIGHER THAN 25 BELOW AT EXCEPT A FEW ISOLATED SPOTS. WITH TEMPS CONTINUING TO RISE THROUGH THE EARLY MORNING...WILL CANCEL THE WIND CHILL ADVISORY A BIT EARLY. THE WARM AIR ADVECTION WILL CONTINUE THROUGH MUCH OF THE DAY TODAY...WITH HIGHS BACK ABOVE ZERO AND EVEN GETTING INTO THE UPPER TEENS AND 20S. TEMPS TONIGHT WILL BE FAIRLY TRICKY AS MUCH WILL DEPEND ON CLOUDS. THINK THAT WE WILL AT LEAST SEE SOME CLEARING OUT EVEN WITH WARM AIR ADVECTION CONTINUING...SO KEPT TEMPS ON THE COOL SIDE IN THE LOW TEENS FOR NOW BUT WILL HAVE TO KEEP AN EYE ON CLOUDS. CLOUDS WILL INCREASE ON FRIDAY WITH THE SFC TROUGH AXIS...BUT SOUTH TO SOUTHWEST WINDS WILL CONTINUE TO BRING WARM AIR INTO THE AREA. KEPT HIGHS IN THE 20S FOR FRIDAY. .LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 305 AM CST THU JAN 9 2014 FRIDAY NIGHT THROUGH SATURDAY NIGHT...THE WARM TREND WILL CONTINUE. THERE MAY BE SOME BRIEF COLD AIR ADVECTION BEHIND THE SFC TROUGH ON FRIDAY BUT 850MB TEMPS STAY IN THE -2 TO -4 RANGE. CLOUDS WILL ALSO HELP KEEP TEMPS IN THE TEENS ABOVE ZERO AT THE SFC. ANOTHER UPPER TROUGH WILL BEGIN DIGGING INTO THE NORTHERN ROCKIES ON SATURDAY AND MOVE OUT INTO THE NORTHERN PLAINS SATURDAY NIGHT. THE MAIN SFC LOW WILL BE TO OUR NORTH...BUT THINK THERE COULD BE SOME PRECIP IN THE WARM AIR ADVECTION ON THE SOUTH SIDE OF THE LOW...SO KEPT 20 TO 30 POPS GOING. THERE WILL BE SOME WARM AIR ALOFT MOVING IN AND THERE IS THE POSSIBILITY OF SOME FREEZING PRECIP ON THE BACKSIDE OF WHATEVER MOVES THROUGH SATURDAY NIGHT. AT THIS POINT WILL LEAVE THE TYPE JUST AS SNOW AND KEEP AN EYE ON THINGS. TEMPS SATURDAY WILL BE IN THE 20S AND NOT FALL OFF TOO MUCH INTO SATURDAY NIGHT. SUNDAY-WEDNESDAY...A SFC LOW WILL PASS TO THE NORTH ON SUNDAY...PUTTING THE AREA IN WESTERLY SFC FLOW BEFORE COLD ADVECTION DEVELOPS LATER IN THE DAY. TEMPS MAY RISE NEAR OR ABOVE FREEZING...DEPENDING ON TIMING OF THE FRONT. KEPT LIGHT SNOW CHANCES OVER NW MN...WITH SOME MIXED PRECIP POSSIBLE...ESPECIALLY IF THE WARMER AND SLOWER ECMWF SOLUTION...WITH 1 TO 3C 850 MB TEMPS...IS CORRECT. AFTER SUNDAY...NORTHWEST FLOW BECOMES ESTABLISHED WITH REINFORCING SHORTWAVES PROPAGATING THROUGH THE FLOW. 850 MB TEMPS WILL NOT BE NEARLY AS COLD AS DURING RECENT DAYS...WITH LESS AMPLITUDE IN THE FLOW AND MORE PACIFIC INFLUENCE IN THE AIR MASS. A SHORTWAVE TROUGH WILL DIVE SOUTHEAST LATE MON/MON NIGHT...BRINGING A CHANCE FOR SOME LIGHT SNOW. TEMPS ARE EXPECTED TO REMAIN SEASONABLE BEHIND THE SYSTEM...ALTHOUGH THE ECMWF DOES BRING IN COLDER TEMPS FOR TUESDAY...ESPECIALLY ACROSS THE EAST. HOWEVER...THE TROUGH IS TRANSITORY...WITH SHORTWAVE RIDGING BUILDING IN BEHIND FOR WEDNESDAY AHEAD OF THE NEXT WAVE. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT) ISSUED AT 1130 PM CST WED JAN 8 2014 AREAS OF MVFR CIGS WILL MOVE THROUGH THE REGION OVERNIGHT...LIKELY EXITING DURING THE LATE MORNING HOURS. THE 03Z RAP INDICATES THAT AN AREA OF IFR CIGS WILL DEVELOP DURING THE LATE MORNING HOURS AND REMAIN INTO THE AFTERNOON HOURS. CONSIDERING UPSTREAM OBSERVATIONS...IFR CIGS WOULD APPEAR TO BE ONLY A VERY LOW PROBABILITY. WINDS WILL CONTINUE TO BE BREEZY FROM THE SOUTH INTO THE AFTERNOON HOURS. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ SHORT TERM...JR LONG TERM...JR/MAKOWSKI AVIATION...TG
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1130 PM CST WED JAN 8 2014 .UPDATE... ISSUED AT 1130 PM CST WED JAN 8 2014 WIND CHILL VALUES HAVE WARMED ENOUGH ACROSS MUCH OF THE SOUTHERN VALLEY AND PORTIONS OF WEST CENTRAL MINNESOTA THAT THE WIND CHILL ADVISORY CAN BE CANCELLED HERE. TEMPERATURES ARE EXPECTED TO CONTINUE RISING. WILL LEAVE THE ADVISORY IN EFFECT ACROSS THE NORTHERN VALLEY AND NORTHWEST MINNESOTA WHERE TEMPERATURES ARE COLDER AND WIND SPEEDS SLIGHTLY STRONGER (BUT CONDITIONS WILL CONTINUE TO IMPROVE). && .SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT) ISSUED AT 252 PM CST WED JAN 8 2014 TEMPS CLOUDS AND WINDS WILL BE THE FORECAST CHALLENGE TONIGHT WITH THE RESULTING COLD WIND CHILLS. AS OF MID AFTERNOON THE SFC HIGH WAS STARTING TO MOVE AWAY FROM THE FA WITH LIGHT SOUTH RETURN FLOW SETTING UP WEST OF THE RED RIVER VALLEY. BAND OF CLOUDS ALMOST INTO OUR SOUTHWEST FA NOW AND THESE SHOULD CONTINUE EXPANDING EASTWARD TONIGHT. SO EXPECT INCREASING CLOUDS AND WINDS SLOWLY EXPANDING EAST ACROSS THE FA. HOWEVER UNTIL THESE REACH THE CENTRAL AND EASTERN FA THERE WILL BE SOME EARLY EVENING TEMP FALL WITH RATHER WEAK WINDS. THEREFORE WIND CHILLS WILL GET DOWN INTO ADVISORY CRITERIA FOR ONE MORE NIGHT. WITH THE CLOUDS NEARING THE FAR WESTERN COUNTIES HAVE ELECTED TO LEAVE THEM OUT OF THE ADVISORY BUT WILL KEEP MOST OTHER COUNTIES FROM 00Z UNTIL 12Z THU. HAD CONSIDERED SEGMENTING THE ADVISORY BUT TIMING CLOUDS WINDS AND TEMPS IS TOUGH SO WENT WITH ONE GROUP AND LATER SHIFTS CAN TRIM COUNTIES AS THEY SEE FIT. LOOKING AT 925MB WINDS REALLY CRANKING UP BY LATE EVENING AND OVERNIGHT WITH SOME PRETTY STRONG WARM ADVECTION. PREVIOUS SHIFTS HAD INSERTED SOME LOW CHANCES FOR LIGHT SNOW AFTER MIDNIGHT INTO THU MORNING AND WILL ALSO ADD SOME BY MID TO LATE EVENING OVER THE KDVL REGION. DID NOT ADD ANY BLSN AS THERE IS A PRETTY DECENT INVERSION BUT THIS WILL ALSO HAVE TO BE WATCHED. SHOULD FINALLY BE OUT OF ADVISORY CRITERIA FOR THIS COLD STRETCH ON THU MORNING. THU HIGHS IN THE TEENS TO LOW 20S LOOK REALLY GOOD. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 252 PM CST WED JAN 8 2014 FOR FRI INTO SAT LEFT THE FORECAST DRY ALTHOUGH SEVERAL MODELS INDICATE SOME VERY LIGHT PCPN POSSIBLE IN THE EAST. LOOKING AT PORTIONS OF THE WEST OR SW FA GETTING SOUTHWEST OR WEST WINDS ON FRI AND SAT SO THOSE AREAS MAY GET A LITTLE WARMER. FOR SAT NIGHT THROUGH WED...TEMPS THROUGH THE PERIOD SHOULD REMAIN ABOVE TO EVEN WELL ABOVE NORMAL AT TIMES. SUNDAY APPEARS TO BE THE WARMEST DAY WITH 850MB TEMPS ABOVE 0C AND EVEN UP TO +6C IN THE SOUTH. THERE WILL BE PERIODIC CHANCES FOR SOME LIGHT SNOW IN NW FLOW ALOFT...AND PERHAPS A STRONGER CLIPPER SYSTEM MONDAY NIGHT INTO TUE...WITH STRONGER WINDS BEHIND A COLD FRONT. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT) ISSUED AT 1130 PM CST WED JAN 8 2014 AREAS OF MVFR CIGS WILL MOVE THROUGH THE REGION OVERNIGHT...LIKELY EXITING DURING THE LATE MORNING HOURS. THE 03Z RAP INDICATES THAT AN AREA OF IFR CIGS WILL DEVELOP DURING THE LATE MORNING HOURS AND REMAIN INTO THE AFTERNOON HOURS. CONSIDERING UPSTREAM OBSERVATIONS...IFR CIGS WOULD APPEAR TO BE ONLY A VERY LOW PROBABILITY. WINDS WILL CONTINUE TO BE BREEZY FROM THE SOUTH INTO THE AFTERNOON HOURS. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...WIND CHILL ADVISORY UNTIL 6 AM CST THURSDAY FOR NDZ008-016-027. MN...WIND CHILL ADVISORY UNTIL 6 AM CST THURSDAY FOR MNZ001-004>009- 013>017-023-024-032. && $$ UPDATE...TG SHORT TERM...GODON LONG TERM...GODON/DK AVIATION...TG
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
1039 PM EST FRI JAN 10 2014 .SYNOPSIS... AN APPROACHING UPPER LEVEL TROUGH WILL MOVE INTO THE AREA TONIGHT...WITH RAIN EXPECTED TONIGHT AND INTO SATURDAY. A COLD FRONT WILL CROSS THE REGION BY SATURDAY AFTERNOON...LOWERING TEMPERATURES THROUGH SUNDAY. HIGH PRESSURE WILL ENTER THE SOUTHEASTERN STATES ON SUNDAY...WITH RIDGING BRINGING FAIR CONDITIONS TO THE OHIO VALLEY THROUGH EARLY MONDAY. && .NEAR TERM /UNTIL 6 AM SATURDAY MORNING/... MOST LOCATIONS EXPERIENCING WIDESPREAD FOG ACROSS THE NORTHERN MIAMI VALLEY AND EAST CENTRAL INDIANA HAVE SEEN IMPROVING CONDITIONS OVER THE COUPLE HOURS. THEREFORE...THE DENSE FOG ADVISORY HAS BEEN CANCELLED. SOUTH AND EAST OF THE NORTHERN MIAMI VALLEY...JUST A FEW AREAS OF LIGHT PRECIPITATION ARE EXPECTED UNTIL MIDNIGHT...AS THE LEADING EDGE OF A LARGE AREA OF RAIN ARRIVES IN THE SOUTHWESTERN ZONES. PREVIOUS DISCUSSION > INCREASING ISENTROPIC LIFT AHEAD OF A DEEPENING MID- LEVEL TROUGH WILL GRADUALLY LEAD TO AN INCREASE IN PRECIPITATION POTENTIAL THIS EVENING...PRIMARILY FOR THE WESTERN HALF OF THE CWA. DESPITE THE RELATIVELY ABUNDANT LOW-LEVEL MOISTURE...IT IS NOT APPARENT THAT CURRENT ECHOES IN THE SOUTHWEST CWA ARE REACHING THE GROUND...SO MEASURABLE PRECIPITATION MAY STILL BE A FEW HOURS OFF. MOST OF THE IMPACTS FROM THE APPROACHING TROUGH AND COLD FRONT WILL BE COVERED IN THE SHORT TERM DISCUSSION. TEMPERATURES OVERNIGHT ARE EXPECTED TO REMAIN RELATIVELY STEADY FOR A WHILE...BEFORE RISING (ESPECIALLY IN THE SOUTHERN CWA) CLOSER TO DAYBREAK. THE RAP WAS USED AS A BASIS FOR THESE NON-DIURNAL TEMPERATURES...AS IT IS HANDLING THE CURRENT SITUATION WELL. && .SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/... AHEAD OF A MID-LEVEL TROUGH MOVING EAST OUT OF THE MISSISSIPPI VALLEY...A SURFACE LOW WILL TRACK NORTHEASTWARD INTO THE GREAT LAKES REGION ON SATURDAY. THIS WILL BRING A COLD FRONT THROUGH THE OHIO VALLEY BY SATURDAY AFTERNOON. AHEAD OF THE COLD FRONT...THE OHIO VALLEY WILL BE WITHIN A REGIME OF DEEP SOUTHERLY FLOW...ADVECTING A VERY MOIST AIR MASS INTO THE REGION. BY EARLY SATURDAY MORNING...PRECIPITABLE WATER VALUES WILL BE WELL OVER AN INCH ACROSS THE ILN CWA...EXCEEDING 300 PERCENT OF NORMAL FOR JANUARY. THE STRONGEST PUSH OF MOISTURE WILL COME ON THE NOSE OF A LOW LEVEL JET BETWEEN 08Z AND 12Z...FOCUSED PRIMARILY ON THE SOUTHERN AND SOUTHEASTERN SECTIONS OF THE ILN CWA. WITH SOUNDINGS APPEARING MOIST ADIABATIC (AS WOULD BE EXPECTED)...INSTABILITY WILL BE HARD TO COME BY. THERE APPEARS TO BE JUST ENOUGH CONDITIONAL ELEVATED INSTABILITY TO SUPPORT A CHANCE OF THUNDER IN THE SOUTH AND SOUTHEAST CWA EARLY SATURDAY MORNING...AND AT THE VERY LEAST...SOME OF THE SHOWERS WILL LIKELY BE A LITTLE BIT CONVECTIVE IN NATURE. THE LARGER-SCALE MODELS INDICATE PRECIPITATION TOTALS OF GENERALLY JUST UNDER AN INCH...WHILE SOME OF THE MESOSCALE MODELS SHOW AN AXIS OF OVER AN INCH THAT WORKS THROUGH THE SOUTH-CENTRAL PORTIONS OF THE ILN CWA. BASED ON THE APPEARANCE OF SIMULATED REFLECTIVITY ON THE HIGH-RES RUNS...AND THE POTENTIAL FOR SOME ISOLATED ELEVATED CONVECTIVE ELEMENTS...SOME LOCALIZED PRECIPITATION AMOUNTS MAY GET AS HIGH AS AN INCH AND A HALF. BASED ON FLASH FLOOD GUIDANCE AND MMEFS RUNS (USING NAEF/SREF/GEFS INPUT)...IT DOES NOT APPEAR THAT THIS WILL BE ENOUGH RAIN TO LEAD TO SIGNIFICANT FLOODING ISSUES. A FEW ACTION STAGE RIVER READINGS...OR PERHAPS AN ADVISORY OR TWO...MAY NOT BE OUT OF THE QUESTION. NON-DIURNAL TEMPERATURE TRENDS ARE BEING CONTINUED THROUGH SATURDAY...AS COLD FRONTAL PASSAGE OCCURS. DEEP MOISTURE WILL DISAPPEAR AFTER THE FRONT HAS PASSED...BUT POPS WILL BE MAINTAINED AS ADDITIONAL RAIN SHOWERS (MIXING WITH SNOW LATE) APPEAR LIKELY. THIS POST-FRONTAL REGIME (UNDER THE MID-LEVEL TROUGH AXIS) WILL BE CHARACTERIZED BY A MIXED LAYER WITH WEAK AND SHALLOW INSTABILITY...AND ABUNDANT LOW- LEVEL MOISTURE. EVENTUALLY...AS THE NIGHT PROGRESSES...MOISTURE BECOMES SHALLOW ENOUGH THAT ICE CRYSTALS MAY NOT BE ABLE TO FORM. FLURRIES HAVE BEEN INTRODUCED THROUGH SATURDAY NIGHT...BUT IT IS VERY POSSIBLE THAT THIS WILL END UP BEING DRIZZLE (OR EVEN FREEZING DRIZZLE BASED ON SURFACE TEMPS). BY SUNDAY MORNING...RIDGING WILL BE ENTERING THE CWA...WITH SURFACE HIGH PRESSURE BUILDING IN FROM THE SOUTH. THE LOW LEVEL MOISTURE MAY NOT ALLOW CLOUDS TO SCOUR VERY QUICKLY...BUT MOSTLY SUNNY SKIES ARE EXPECTED BY AFTERNOON FOR MOST OF THE CWA (WITH CLOUDS DISSIPATING EARLIER IN THE SOUTH). WITH THE CWA RETURNING TO A WARM ADVECTION PATTERN...TEMPS WILL RISE AGAIN ON SUNDAY...AND STRUGGLE TO EVEN CROSS BACK UNDER THE FREEZING MARK ON SUNDAY NIGHT / EARLY MONDAY MORNING. && .LONG TERM /MONDAY THROUGH FRIDAY/... RAIN WILL BE LIKELY MONDAY AS A SURGE OF GULF MOISTURE MOVES UP A FRONTAL BOUNDARY ON A SOUTHWEST UPPER FLOW. SOME LOCATIONS MAY SEE AN INCH OF RAIN WITH THIS EVENT. RAIN AND SNOW SHOWERS ARE POSSIBLE FOR TUESDAY IN THE NORTHWEST FLOW BEHIND THE FRONT. SNOW SHOWERS MAY LINGER ON WEDNESDAY IN THE COLDER NORTHWEST FLOW. A PERIOD OF DRY WEATHER IS INDICATED FOR THURSDAY WHEN A RIDGE OF HIGH PRESSURE IS FORECAST TO PUSH ACROSS THE REGION. SNOW SHOWERS WILL BE POSSIBLE AGAIN ON FRIDAY DUE TO A TROUGH AND ASSOCIATED MOISTURE AND COLD ADVECTION. TEMPERATURES WILL START ABOVE NORMAL MONDAY AND TUESDAY...WITH HIGHS MAINLY IN THE 40S. COLD ADVECTION WILL PUSH READINGS BELOW NORMAL ON WEDNESDAY AND FRIDAY WITH HIGHS IN THE 20S...WHILE THE RIDGE WILL PROVIDE SOME WARM ADVECTION AND NEAR NORMAL 30S FOR THURSDAY. && .AVIATION /04Z SATURDAY THROUGH WEDNESDAY/... ABUNDANT MOISTURE OVER COLD SURFACES WILL CONTINUE TO PRODUCE PERIODS OF IFR FOG AND CIGS ACROSS KDAY AND LOCATIONS NEAR THIS AREA THROUGH PORTIONS OF THE THE EVENING...BEFORE THIS BAND OF FOG LIFTS NORTHWARD. MVFR CIGS WILL BE LIKELY ELSEWHERE. THERE MAY BE A FEW HOUR WINDOW THIS EVENING WHERE THE SOUTHERN TERMINALS SEE VFR CONDITIONS...BEFORE RAIN BRINGS LOWERING CIGS AND VSBYS TO THOSE LOCATIONS. RAIN WILL SPREAD WEST TO EAST AFTER MIDNIGHT...AFFECTING ALL TERMINALS DURING THE PRE DAWN HOURS WITH MVFR VSBYS IFR CIGS. A COLD FRONT WILL MOVE ACROSS THE AREA DURING THE MORNING...WHICH WILL HELP VSBYS AND CIGS TO GRADUALLY IMPROVE...WHILE WINDS INCREASE OUT OF THE SOUTHWEST. BY THE LATE MORNING...CIGS SHOULD RISE TO MVFR WITH SOUTHWEST TO WEST WINDS GUSTING UP TO 25 KT. THESE WINDS AND CIGS WILL LIKELY PERSIST INTO THE EVENING. OUTLOOK...MVFR CEILINGS LIKELY THROUGH SATURDAY NIGHT. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...NONE. KY...NONE. IN...NONE. && $$ SYNOPSIS...HATZOS NEAR TERM...HATZOS/LATTO SHORT TERM...HATZOS LONG TERM...CONIGLIO AVIATION...LATTO
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
942 PM EST FRI JAN 10 2014 .SYNOPSIS... AN APPROACHING UPPER LEVEL TROUGH WILL MOVE INTO THE AREA TONIGHT...WITH RAIN EXPECTED TONIGHT AND INTO SATURDAY. A COLD FRONT WILL CROSS THE REGION BY SATURDAY AFTERNOON...LOWERING TEMPERATURES THROUGH SUNDAY. HIGH PRESSURE WILL ENTER THE SOUTHEASTERN STATES ON SUNDAY...WITH RIDGING BRINGING FAIR CONDITIONS TO THE OHIO VALLEY THROUGH EARLY MONDAY. && .NEAR TERM /UNTIL 6 AM SATURDAY MORNING/... MOST LOCATIONS EXPERIENCING WIDESPREAD FOG ACROSS THE NORTHERN MIAMI VALLEY AND EAST CENTRAL INDIANA HAVE SEEN IMPROVING CONDITIONS OVER THE PAST HOUR. WILL CONTINUE THE DENSE FOG ADVISORY IN EFFECT UNTIL MIDNIGHT FOR WAYNE CO INDIANA...AND PREBLE/DARKE OHIO WHERE THERE APPEARS TO BE QUARTER MILE VISIBILITIES REMAINING. OTHER LOCATIONS UNDER THE INITIAL ADVISORY PORTION THAT HAS BEEN CANCELLED HAVE THE MAJORITY OF OBS NOW COMING IN AT 2 MILES OR BETTER. HOWEVER...WITH THE CLOUD DECK ONLY A COUPLE HUNDRED FEET OFF THE SURFACE...PATCHY DENSE FOG WILL BE POSSIBLE FOR THE NEXT FEW HOURS. SOUTH AND EAST OF THE NORTHERN MIAMI VALLEY...JUST A FEW AREAS OF LIGHT PRECIPITATION ARE EXPECTED UNTIL MIDNIGHT...AS THE LEADING EDGE OF A LARGE AREA OF RAIN ARRIVES IN THE SOUTHWESTERN ZONES. PREVIOUS DISCUSSION > INCREASING ISENTROPIC LIFT AHEAD OF A DEEPENING MID- LEVEL TROUGH WILL GRADUALLY LEAD TO AN INCREASE IN PRECIPITATION POTENTIAL THIS EVENING...PRIMARILY FOR THE WESTERN HALF OF THE CWA. DESPITE THE RELATIVELY ABUNDANT LOW-LEVEL MOISTURE...IT IS NOT APPARENT THAT CURRENT ECHOES IN THE SOUTHWEST CWA ARE REACHING THE GROUND...SO MEASURABLE PRECIPITATION MAY STILL BE A FEW HOURS OFF. MOST OF THE IMPACTS FROM THE APPROACHING TROUGH AND COLD FRONT WILL BE COVERED IN THE SHORT TERM DISCUSSION. TEMPERATURES OVERNIGHT ARE EXPECTED TO REMAIN RELATIVELY STEADY FOR A WHILE...BEFORE RISING (ESPECIALLY IN THE SOUTHERN CWA) CLOSER TO DAYBREAK. THE RAP WAS USED AS A BASIS FOR THESE NON-DIURNAL TEMPERATURES...AS IT IS HANDLING THE CURRENT SITUATION WELL. && .SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/... AHEAD OF A MID-LEVEL TROUGH MOVING EAST OUT OF THE MISSISSIPPI VALLEY...A SURFACE LOW WILL TRACK NORTHEASTWARD INTO THE GREAT LAKES REGION ON SATURDAY. THIS WILL BRING A COLD FRONT THROUGH THE OHIO VALLEY BY SATURDAY AFTERNOON. AHEAD OF THE COLD FRONT...THE OHIO VALLEY WILL BE WITHIN A REGIME OF DEEP SOUTHERLY FLOW...ADVECTING A VERY MOIST AIR MASS INTO THE REGION. BY EARLY SATURDAY MORNING...PRECIPITABLE WATER VALUES WILL BE WELL OVER AN INCH ACROSS THE ILN CWA...EXCEEDING 300 PERCENT OF NORMAL FOR JANUARY. THE STRONGEST PUSH OF MOISTURE WILL COME ON THE NOSE OF A LOW LEVEL JET BETWEEN 08Z AND 12Z...FOCUSED PRIMARILY ON THE SOUTHERN AND SOUTHEASTERN SECTIONS OF THE ILN CWA. WITH SOUNDINGS APPEARING MOIST ADIABATIC (AS WOULD BE EXPECTED)...INSTABILITY WILL BE HARD TO COME BY. THERE APPEARS TO BE JUST ENOUGH CONDITIONAL ELEVATED INSTABILITY TO SUPPORT A CHANCE OF THUNDER IN THE SOUTH AND SOUTHEAST CWA EARLY SATURDAY MORNING...AND AT THE VERY LEAST...SOME OF THE SHOWERS WILL LIKELY BE A LITTLE BIT CONVECTIVE IN NATURE. THE LARGER-SCALE MODELS INDICATE PRECIPITATION TOTALS OF GENERALLY JUST UNDER AN INCH...WHILE SOME OF THE MESOSCALE MODELS SHOW AN AXIS OF OVER AN INCH THAT WORKS THROUGH THE SOUTH-CENTRAL PORTIONS OF THE ILN CWA. BASED ON THE APPEARANCE OF SIMULATED REFLECTIVITY ON THE HIGH-RES RUNS...AND THE POTENTIAL FOR SOME ISOLATED ELEVATED CONVECTIVE ELEMENTS...SOME LOCALIZED PRECIPITATION AMOUNTS MAY GET AS HIGH AS AN INCH AND A HALF. BASED ON FLASH FLOOD GUIDANCE AND MMEFS RUNS (USING NAEF/SREF/GEFS INPUT)...IT DOES NOT APPEAR THAT THIS WILL BE ENOUGH RAIN TO LEAD TO SIGNIFICANT FLOODING ISSUES. A FEW ACTION STAGE RIVER READINGS...OR PERHAPS AN ADVISORY OR TWO...MAY NOT BE OUT OF THE QUESTION. NON-DIURNAL TEMPERATURE TRENDS ARE BEING CONTINUED THROUGH SATURDAY...AS COLD FRONTAL PASSAGE OCCURS. DEEP MOISTURE WILL DISAPPEAR AFTER THE FRONT HAS PASSED...BUT POPS WILL BE MAINTAINED AS ADDITIONAL RAIN SHOWERS (MIXING WITH SNOW LATE) APPEAR LIKELY. THIS POST-FRONTAL REGIME (UNDER THE MID-LEVEL TROUGH AXIS) WILL BE CHARACTERIZED BY A MIXED LAYER WITH WEAK AND SHALLOW INSTABILITY...AND ABUNDANT LOW- LEVEL MOISTURE. EVENTUALLY...AS THE NIGHT PROGRESSES...MOISTURE BECOMES SHALLOW ENOUGH THAT ICE CRYSTALS MAY NOT BE ABLE TO FORM. FLURRIES HAVE BEEN INTRODUCED THROUGH SATURDAY NIGHT...BUT IT IS VERY POSSIBLE THAT THIS WILL END UP BEING DRIZZLE (OR EVEN FREEZING DRIZZLE BASED ON SURFACE TEMPS). BY SUNDAY MORNING...RIDGING WILL BE ENTERING THE CWA...WITH SURFACE HIGH PRESSURE BUILDING IN FROM THE SOUTH. THE LOW LEVEL MOISTURE MAY NOT ALLOW CLOUDS TO SCOUR VERY QUICKLY...BUT MOSTLY SUNNY SKIES ARE EXPECTED BY AFTERNOON FOR MOST OF THE CWA (WITH CLOUDS DISSIPATING EARLIER IN THE SOUTH). WITH THE CWA RETURNING TO A WARM ADVECTION PATTERN...TEMPS WILL RISE AGAIN ON SUNDAY...AND STRUGGLE TO EVEN CROSS BACK UNDER THE FREEZING MARK ON SUNDAY NIGHT / EARLY MONDAY MORNING. && .LONG TERM /MONDAY THROUGH FRIDAY/... RAIN WILL BE LIKELY MONDAY AS A SURGE OF GULF MOISTURE MOVES UP A FRONTAL BOUNDARY ON A SOUTHWEST UPPER FLOW. SOME LOCATIONS MAY SEE AN INCH OF RAIN WITH THIS EVENT. RAIN AND SNOW SHOWERS ARE POSSIBLE FOR TUESDAY IN THE NORTHWEST FLOW BEHIND THE FRONT. SNOW SHOWERS MAY LINGER ON WEDNESDAY IN THE COLDER NORTHWEST FLOW. A PERIOD OF DRY WEATHER IS INDICATED FOR THURSDAY WHEN A RIDGE OF HIGH PRESSURE IS FORECAST TO PUSH ACROSS THE REGION. SNOW SHOWERS WILL BE POSSIBLE AGAIN ON FRIDAY DUE TO A TROUGH AND ASSOCIATED MOISTURE AND COLD ADVECTION. TEMPERATURES WILL START ABOVE NORMAL MONDAY AND TUESDAY...WITH HIGHS MAINLY IN THE 40S. COLD ADVECTION WILL PUSH READINGS BELOW NORMAL ON WEDNESDAY AND FRIDAY WITH HIGHS IN THE 20S...WHILE THE RIDGE WILL PROVIDE SOME WARM ADVECTION AND NEAR NORMAL 30S FOR THURSDAY. && .AVIATION /03Z SATURDAY THROUGH WEDNESDAY/... ABUNDANT MOISTURE OVER COLD SURFACES WILL CONTINUE TO PRODUCE PERIODS OF IFR FOG AND CIGS ACROSS KDAY AND LOCATIONS NEAR THIS AREA THROUGH PORTIONS OF THE THE EVENING...BEFORE THIS BAND OF FOG LIFTS NORTHWARD. MVFR CIGS WILL BE LIKELY ELSEWHERE. THERE MAY BE A FEW HOUR WINDOW THIS EVENING WHERE THE SOUTHERN TERMINALS SEE VFR CONDITIONS...BEFORE RAIN BRINGS LOWERING CIGS AND VSBYS TO THOSE LOCATIONS. RAIN WILL SPREAD WEST TO EAST AFTER MIDNIGHT...AFFECTING ALL TERMINALS DURING THE PRE DAWN HOURS WITH MVFR VSBYS IFR CIGS. A COLD FRONT WILL MOVE ACROSS THE AREA DURING THE MORNING...WHICH WILL HELP VSBYS AND CIGS TO GRADUALLY IMPROVE...WHILE WINDS INCREASE OUT OF THE SOUTHWEST. BY THE LATE MORNING...CIGS SHOULD RISE TO MVFR WITH SOUTHWEST TO WEST WINDS GUSTING UP TO 25 KT. THESE WINDS AND CIGS WILL LIKELY PERSIST INTO THE EVENING. OUTLOOK...MVFR CEILINGS LIKELY THROUGH SATURDAY NIGHT. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...DENSE FOG ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR OHZ042-060. KY...NONE. IN...DENSE FOG ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR INZ050. && $$ SYNOPSIS...HATZOS NEAR TERM...LATTO/HATZOS SHORT TERM...HATZOS LONG TERM...CONIGLIO AVIATION...LATTO
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
704 PM EST FRI JAN 10 2014 .SYNOPSIS... AN APPROACHING UPPER LEVEL TROUGH WILL MOVE INTO THE AREA TONIGHT...WITH RAIN EXPECTED TONIGHT AND INTO SATURDAY. A COLD FRONT WILL CROSS THE REGION BY SATURDAY AFTERNOON...LOWERING TEMPERATURES THROUGH SUNDAY. HIGH PRESSURE WILL ENTER THE SOUTHEASTERN STATES ON SUNDAY...WITH RIDGING BRINGING FAIR CONDITIONS TO THE OHIO VALLEY THROUGH EARLY MONDAY. && .NEAR TERM /UNTIL 6 AM SATURDAY MORNING/... A QUICK UPDATE HAS BEEN PRODUCED TO ALLOW FOR THE ISSUANCE OF A DENSE FOG ADVISORY. THE AREA OF DENSE FOG HAS CONTINUED TO EXPAND NORTHWARD...ENVELOPING LARGE ENOUGH SECTIONS OF SEVERAL COUNTIES TO REQUIRE AN ADVISORY TO BE ISSUED. THE SOUTHERN EDGE OF THIS ADVISORY WILL LIKELY BE ABLE TO BE DROPPED EARLY...AS VISIBILITIES ARE VERY GRADUALLY IMPROVING FROM THE SOUTH. HOWEVER...THE NEWEST HIGH-RESOLUTION MODEL DATA INDICATES THAT SURFACE SATURATION IS LIKELY TO CONTINUE IN THE NORTHWESTERN CWA FOR AT LEAST SEVERAL MORE HOURS. PREVIOUS DISCUSSION > THE PRIMARY WEATHER CONCERN FOR THE NEAR TERM IS FOG POTENTIAL. A NARROW AXIS FROM THE WEST-CENTRAL CWA (AROUND FRANKLIN COUNTY INDIANA) THROUGH THE NORTHEAST CWA (DELAWARE COUNTY OHIO) CONTAINS A FEW OBSERVATION SITES REPORTING QUARTER-MILE DENSE FOG. RH PROJECTIONS AND SREF/HRRR/RAP VISIBILITY PRODUCTS ALL INDICATE A POTENTIAL FOR THIS TO CONTINUE TONIGHT...WITH THE LOWER VISIBILITIES GRADUALLY SHIFTING NORTH AND WEST WITH TIME. FOR NOW THIS THREAT WILL BE COVERED BY THE HWO AND A NEW SPECIAL WEATHER STATEMENT...BUT IF THE DENSE AREA EXPANDS AT ALL...AN ADVISORY MAY BECOME NECESSARY. RIGHT NOW...THIS AREA IS FAIRLY NARROW AND NOT WIDESPREAD ENOUGH TO REQUIRE A HEADLINE. INCREASING ISENTROPIC LIFT AHEAD OF A DEEPENING MID-LEVEL TROUGH WILL GRADUALLY LEAD TO AN INCREASE IN PRECIPITATION POTENTIAL THIS EVENING...PRIMARILY FOR THE WESTERN HALF OF THE CWA. DESPITE THE RELATIVELY ABUNDANT LOW-LEVEL MOISTURE...IT IS NOT APPARENT THAT CURRENT ECHOES IN THE SOUTHWEST CWA ARE REACHING THE GROUND...SO MEASURABLE PRECIPITATION MAY STILL BE A FEW HOURS OFF. MOST OF THE IMPACTS FROM THE APPROACHING TROUGH AND COLD FRONT WILL BE COVERED IN THE SHORT TERM DISCUSSION. TEMPERATURES OVERNIGHT ARE EXPECTED TO REMAIN RELATIVELY STEADY FOR A WHILE...BEFORE RISING (ESPECIALLY IN THE SOUTHERN CWA) CLOSER TO DAYBREAK. THE RAP WAS USED AS A BASIS FOR THESE NON-DIURNAL TEMPERATURES...AS IT IS HANDLING THE CURRENT SITUATION WELL. && .SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/... AHEAD OF A MID-LEVEL TROUGH MOVING EAST OUT OF THE MISSISSIPPI VALLEY...A SURFACE LOW WILL TRACK NORTHEASTWARD INTO THE GREAT LAKES REGION ON SATURDAY. THIS WILL BRING A COLD FRONT THROUGH THE OHIO VALLEY BY SATURDAY AFTERNOON. AHEAD OF THE COLD FRONT...THE OHIO VALLEY WILL BE WITHIN A REGIME OF DEEP SOUTHERLY FLOW...ADVECTING A VERY MOIST AIR MASS INTO THE REGION. BY EARLY SATURDAY MORNING...PRECIPITABLE WATER VALUES WILL BE WELL OVER AN INCH ACROSS THE ILN CWA...EXCEEDING 300 PERCENT OF NORMAL FOR JANUARY. THE STRONGEST PUSH OF MOISTURE WILL COME ON THE NOSE OF A LOW LEVEL JET BETWEEN 08Z AND 12Z...FOCUSED PRIMARILY ON THE SOUTHERN AND SOUTHEASTERN SECTIONS OF THE ILN CWA. WITH SOUNDINGS APPEARING MOIST ADIABATIC (AS WOULD BE EXPECTED)...INSTABILITY WILL BE HARD TO COME BY. THERE APPEARS TO BE JUST ENOUGH CONDITIONAL ELEVATED INSTABILITY TO SUPPORT A CHANCE OF THUNDER IN THE SOUTH AND SOUTHEAST CWA EARLY SATURDAY MORNING...AND AT THE VERY LEAST...SOME OF THE SHOWERS WILL LIKELY BE A LITTLE BIT CONVECTIVE IN NATURE. THE LARGER-SCALE MODELS INDICATE PRECIPITATION TOTALS OF GENERALLY JUST UNDER AN INCH...WHILE SOME OF THE MESOSCALE MODELS SHOW AN AXIS OF OVER AN INCH THAT WORKS THROUGH THE SOUTH-CENTRAL PORTIONS OF THE ILN CWA. BASED ON THE APPEARANCE OF SIMULATED REFLECTIVITY ON THE HIGH-RES RUNS...AND THE POTENTIAL FOR SOME ISOLATED ELEVATED CONVECTIVE ELEMENTS...SOME LOCALIZED PRECIPITATION AMOUNTS MAY GET AS HIGH AS AN INCH AND A HALF. BASED ON FLASH FLOOD GUIDANCE AND MMEFS RUNS (USING NAEF/SREF/GEFS INPUT)...IT DOES NOT APPEAR THAT THIS WILL BE ENOUGH RAIN TO LEAD TO SIGNIFICANT FLOODING ISSUES. A FEW ACTION STAGE RIVER READINGS...OR PERHAPS AN ADVISORY OR TWO...MAY NOT BE OUT OF THE QUESTION. NON-DIURNAL TEMPERATURE TRENDS ARE BEING CONTINUED THROUGH SATURDAY...AS COLD FRONTAL PASSAGE OCCURS. DEEP MOISTURE WILL DISAPPEAR AFTER THE FRONT HAS PASSED...BUT POPS WILL BE MAINTAINED AS ADDITIONAL RAIN SHOWERS (MIXING WITH SNOW LATE) APPEAR LIKELY. THIS POST-FRONTAL REGIME (UNDER THE MID-LEVEL TROUGH AXIS) WILL BE CHARACTERIZED BY A MIXED LAYER WITH WEAK AND SHALLOW INSTABILITY...AND ABUNDANT LOW- LEVEL MOISTURE. EVENTUALLY...AS THE NIGHT PROGRESSES...MOISTURE BECOMES SHALLOW ENOUGH THAT ICE CRYSTALS MAY NOT BE ABLE TO FORM. FLURRIES HAVE BEEN INTRODUCED THROUGH SATURDAY NIGHT...BUT IT IS VERY POSSIBLE THAT THIS WILL END UP BEING DRIZZLE (OR EVEN FREEZING DRIZZLE BASED ON SURFACE TEMPS). BY SUNDAY MORNING...RIDGING WILL BE ENTERING THE CWA...WITH SURFACE HIGH PRESSURE BUILDING IN FROM THE SOUTH. THE LOW LEVEL MOISTURE MAY NOT ALLOW CLOUDS TO SCOUR VERY QUICKLY...BUT MOSTLY SUNNY SKIES ARE EXPECTED BY AFTERNOON FOR MOST OF THE CWA (WITH CLOUDS DISSIPATING EARLIER IN THE SOUTH). WITH THE CWA RETURNING TO A WARM ADVECTION PATTERN...TEMPS WILL RISE AGAIN ON SUNDAY...AND STRUGGLE TO EVEN CROSS BACK UNDER THE FREEZING MARK ON SUNDAY NIGHT / EARLY MONDAY MORNING. && .LONG TERM /MONDAY THROUGH FRIDAY/... RAIN WILL BE LIKELY MONDAY AS A SURGE OF GULF MOISTURE MOVES UP A FRONTAL BOUNDARY ON A SOUTHWEST UPPER FLOW. SOME LOCATIONS MAY SEE AN INCH OF RAIN WITH THIS EVENT. RAIN AND SNOW SHOWERS ARE POSSIBLE FOR TUESDAY IN THE NORTHWEST FLOW BEHIND THE FRONT. SNOW SHOWERS MAY LINGER ON WEDNESDAY IN THE COLDER NORTHWEST FLOW. A PERIOD OF DRY WEATHER IS INDICATED FOR THURSDAY WHEN A RIDGE OF HIGH PRESSURE IS FORECAST TO PUSH ACROSS THE REGION. SNOW SHOWERS WILL BE POSSIBLE AGAIN ON FRIDAY DUE TO A TROUGH AND ASSOCIATED MOISTURE AND COLD ADVECTION. TEMPERATURES WILL START ABOVE NORMAL MONDAY AND TUESDAY...WITH HIGHS MAINLY IN THE 40S. COLD ADVECTION WILL PUSH READINGS BELOW NORMAL ON WEDNESDAY AND FRIDAY WITH HIGHS IN THE 20S...WHILE THE RIDGE WILL PROVIDE SOME WARM ADVECTION AND NEAR NORMAL 30S FOR THURSDAY. && .AVIATION /00Z SATURDAY THROUGH WEDNESDAY/... ABUNDANT MOISTURE OVER COLD SURFACES WILL CONTINUE TO PRODUCE PERIODS OF IFR FOG AND CIGS ACROSS KDAY AND LOCATIONS NEAR THIS AREA THROUGH PORTIONS OF THE THE EVENING...BEFORE THIS BAND OF FOG LIFTS NORTHWARD. MVFR CIGS WILL BE LIKELY ELSEWHERE. THERE MAY BE A FEW HOUR WINDOW THIS EVENING WHERE THE SOUTHERN TERMINALS SEE VFR CONDITIONS...BEFORE RAIN BRINGS LOWERING CIGS AND VSBYS TO THOSE LOCATIONS. RAIN WILL SPREAD WEST TO EAST AFTER MIDNIGHT...AFFECTING ALL TERMINALS DURING THE PRE DAWN HOURS WITH MVFR VSBYS IFR CIGS. A COLD FRONT WILL MOVE ACROSS THE AREA DURING THE MORNING...WHICH WILL HELP VSBYS AND CIGS TO GRADUALLY IMPROVE...WHILE WINDS INCREASE OUT OF THE SOUTHWEST. BY THE LATE MORNING...CIGS SHOULD RISE TO MVFR WITH SOUTHWEST TO WEST WINDS GUSTING UP TO 25 KT. THESE WINDS AND CIGS WILL LIKELY PERSIST INTO THE EVENING. OUTLOOK...MVFR CEILINGS LIKELY THROUGH SATURDAY NIGHT. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...DENSE FOG ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR OHZ026-034- 035-042>045-051>053-060-061. KY...NONE. IN...DENSE FOG ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR INZ050-058- 059. && $$ SYNOPSIS...HATZOS NEAR TERM...HATZOS SHORT TERM...HATZOS LONG TERM...CONIGLIO AVIATION...LATTO
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
1254 PM EST THU JAN 9 2014 .SYNOPSIS... A DISTURBANCE WILL BRING A MIX OF PRECIPITATION ACROSS THE AREA TODAY INTO TONIGHT. A STRONGER SYSTEM WILL BEGIN TO BRING RAIN TO THE AREA ON FRIDAY WITH MORE WIDESPREAD RAIN EXPECTED FRIDAY NIGHT INTO SATURDAY. HIGH PRESSURE WILL ALLOW FOR DRY CONDITIONS ON SUNDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... THE HRRR HAS BEEN HANDLING THE PLACEMENT OF THE LIGHT SNOW THE BEST THE PAST SEVERAL HOURS. WENT CLOSELY TO THE HRRR FOR PLACEMENT OF ADDITIONAL LIGHT SNOW OVER THE NEXT FEW HOURS ACROSS PRIMARILY SOUTHERN PORTIONS OF THE FA. THERE WILL BE A BRIEF LULL IN THE PRECIPITATION LATER THIS MORNING BEFORE ADDITIONAL PRECIPITATION ASSOCIATED WITH AN UPPER LEVEL DISTURBANCE BEGINS TO MOVE INTO THE REGION. LIGHT PRECIPITATION WILL BEGIN TO MOVE INTO WESTERN PORTIONS OF THE FA BY THIS AFTERNOON. PRECIPITATION CHANCES WILL SLOWLY INCREASE ACROSS THE FA THIS AFTERNOON AND INTO THE EVENING HOURS. NW PORTIONS OF THE FA ARE EXPECTED TO GET SOME LIGHT SNOW...SE LIGHT RAIN...AND THEN THE CHANCE FOR SOME LIGHT FREEZING RAIN IN BETWEEN. && .SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/... ISENTROPIC LIFT WILL INCREASE ACROSS THE FA THIS EVENING. PRECIPITATION CHANCES WILL INCREASE AND INCREASED PRECIPITATION CHANCES TO THE LIKELY CATEGORY. WENT NON DIURNAL FOR TEMPERATURES THURSDAY NIGHT. LOW TEMPERATURES WILL BE IN THE EVENING HOURS BEFORE SLOWLY RISING A COUPLE OF DEGREES OVERNIGHT THURSDAY NIGHT. PRECIPITATION WILL CONTINUE TO BE A MIX THURSDAY NIGHT. ACCUMULATING SNOW WILL PRIMARILY BE CONFINED TO THE NW HALF OF THE FA WITH AROUND AN INCH OR LESS OF SNOW EXPECTED. MANY LOCATIONS ACROSS CENTRAL AND SOUTHERN PORTIONS OF THE FA HAVE THE POTENTIAL FOR SOME LIGHT FREEZING RAIN AND SUBSEQUENTLY LIGHT ICE ACCUMULATION. ICE ACCUMULATIONS THAT DO OCCUR WILL BE LESS THAN A TENTH OF AN INCH. AS TEMPERATURES SLOWLY RISE THURSDAY NIGHT FREEZING RAIN WILL BECOME LESS OF AN ISSUE FROM SOUTH TO NORTH ACROSS THE AREA. SOME RESIDUAL SHOWER ACTIVITY WILL LINGER INTO THE FRIDAY MORNING HOURS. A MORE POTENT STORM SYSTEM WILL BEGIN TO MOVE INTO THE AREA ON FRIDAY AND BRING WIDESPREAD RAIN TO THE REGION FRIDAY NIGHT INTO SATURDAY. THERE ARE SOME SUBTLE DIFFERENCES IN THE TIMING OF THE MODELS WITH THIS PRECIPITATION HOWEVER MODELS ARE CONSISTENT IN BRINGING UPWARDS OF AN INCH OF RAIN ACROSS THE REGION. COOLER AIR WILL BEGIN TO WORK INTO THE REGION ON SATURDAY AND RAIN WILL TRANSITION BRIEFLY TO LIGHT SNOW ACROSS THE AREA. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... DRY WEATHER IS INDICATED FOR SUNDAY AND MONDAY AS HIGH PRESSURE BUILDS IN FROM THE SOUTHWEST. FOR MONDAY NIGHT AND TUESDAY...RAIN AND SNOW MAY DEVELOP AS LOW PRESSURE TRACKS UP THE EAST COAST. THIS EVENT WOULD AFFECT MAINLY SOUTHEASTERN LOCATIONS CLOSER TO THE SHIELD OF ATLANTIC MOISTURE. SNOW SHOWERS MAY OCCUR TUESDAY NIGHT AND WEDNESDAY IN THE COLDER NORTHWEST FLOW BEHIND THE DEPARTING COASTAL LOW. MODEL TEMPERATURE GUIDANCE SHOWS ABOVE NORMAL HIGHS MAINLY IN THE 40S FOR SUNDAY THROUGH TUESDAY. A SWITCH TO SLIGHTLY BELOW NORMAL HIGHS IN THE 30S IS ANTICIPATED FOR WEDNESDAY IN COLD ADVECTION. && .AVIATION /18Z THURSDAY THROUGH TUESDAY/... MID LEVEL ZONAL FLOW ACRS THE OHIO VALLEY WITH ISENTROPIC LIFT DEVELOPING ACRS THE TAFS SITES LATE THIS AFTN INTO THE EARLY EVENING. EXPECT LIGHT PRECIPITATION TO OVERSPREAD THE TAF SITES IN RESPONSE TO THIS ISENTROPIC LIFT. INITIALLY PRECIP EXPECTED TO START OUT AS SNOW BUT THEN CHANGE OVER TO RAIN UNDER THE INFLUENCE OF WARM AIR ADVECTION AHD OF MID LEVEL PERTURBATION. A PERIOD OF LIGHT FREEZING RAIN WILL BE POSSIBLE MAINLY ACRS THE NRN TAF SITES THIS EVENING DURG THE TRANSITION UNTIL TEMPERATURES WARM UP ABOVE FREEZING. HAVE NOT MENTIONED THIS FREEZING RAIN AT THIS TIME SINCE IT SHOULD BE LIMITED IN DURATION AND AMOUNT. BEST LIFT TO OCCUR THIS EVENING WHEN PRECIP IS EXPECTED TO BECOME WIDESPREAD. IFR VSBYS WILL BE LKLY WITH MVFR TO IFR CIGS EXPECTED. BEST LIFT SHIFTS EAST AROUND 06Z...WITH PRECIPITATION DIMINISHING. SOME LINGERING LIGHT RAIN OR DRIZZLE WL LKLY CONTINUE OVERNIGHT. NUMERICAL MODELS INDICATING A GOOD DEAL OF LOW LEVEL MOISTURE LATE TONIGHT. IFR CIGS WILL BE POSSIBLE LATE TONIGHT WITH THE BEST CHANCE ACRS THE NORTHERN TAF SITES. HAVE LIMITED IFR CIGS TO KDAY AND KILN BUT CAN NOT RULE OUT THIS CHANCE ACRS ALL TAF SITES. EXPECT IFR TO MVFR CONDITIONS TO BE SLOW TO IMPROVE FRIDAY WITH A GENERAL LULL IN PRECIP BEING IN BETWEEN SYSTEMS. OUTLOOK...MVFR CEILINGS LIKELY FRIDAY THROUGH SATURDAY NIGHT. MVFR VISIBILITIES POSSIBLE FRIDAY NIGHT AND SATURDAY. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...NONE. KY...NONE. IN...NONE. && $$ SYNOPSIS...NOVAK NEAR TERM...AR SHORT TERM...NOVAK LONG TERM...CONIGLIO AVIATION...AR
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
1248 PM EST THU JAN 9 2014 .SYNOPSIS... WEAK HIGH PRESSURE PASSES TODAY...FOLLOWED BY A WEAK DISTURBANCE TONIGHT. TEMPERATURES MODERATING INTO SATURDAY BEFORE COLD FRONT WITH RAIN CROSSES. WEAK HIGH PRESSURE PASSES SUNDAY. && .NEAR TERM /THROUGH TONIGHT/... UPDATE... WORKING ON THE AFTERNOON ISSUANCE AND HAVE REVAMPED THE POP GRIDS FOR TIMING USING THE SREF AND LOCAL HRRR AND WRF MODELS. STILL WORKING ON THE PRECIPITATION TYPES FOR TONIGHT. PREVIOUS DISCUSSION... SURFACE HIGH SHIFTS EASTWARD AS OVER-RUNNING WARM AIR AND ASSOCIATED SFC FRONT PUSH UP FROM THE SOUTH EAST. EXTENSIVE MID LEVEL CLOUD DECK PUSHING UP ACROSS EASTERN TN AND WV THIS MORNING AND WILL CONTINUE THIS PROCESS FOR THE NEXT 12 TO 24 HOURS. WEAK DISTURBANCE TRACKS NORTH AND ACROSS TONIGHT. THIS FEATURE WILL BRING SOME LIGHT SHOWERS TO THE FORECAST AREA. WITH WAA ALOFT...WE ARE LIKELY TO SEE A MIXED BAG OF PRECIPITATION...ALBEIT QPF AMOUNTS WILL BE QUITE LIGHT. HAVE BUMPED POPS AND EXTENDED MENTION OF ISOLD SHOWERS PAST 12 FRIDAY KEEPING QPF AMOUNTS ON THE LIGHT SIDE. LITTLE TO NO ADJUSTMENTS MADE TO TEMPS AS INHERITED FORECAST THAT STRADDLES THE MET AND MAV GUIDANCE LOOKING REASONABLE. && .SHORT TERM /FRIDAY THROUGH SUNDAY/... NOT MUCH CHANGE FROM PREV FORECAST. DID SPEED UP FRONT ON SATURDAY A BIT BASED ON LATEST MODEL RUNS. A FEW SPITS OR SPATS OF -FRZ RA POSSIBLE EARLY FRI MORNING WITH DEPARTING MID LEVEL SYS. LOW CLOUDS WILL HANG TOUGH THOUGH INTO FRIDAY NIGHT. IT WILL REMAIN QUITE MILD ON FRIDAY NIGHT AMID STRENGTHENING LOW LEVEL SW FLOW. AFOREMENTIONED COLD FRONT CROSSES 12-18Z ON SATURDAY. QPF AMOUNTS HALF AN INCH TO ONE INCH WILL BE COMMON WITH PERHAPS SOME GUSTY WINDS ON THE HILLTOPS AND RIDGES. HIGHS STILL LOOK TO REACH INTO MID TO UPPER 50S. DEEP MOISTURE QUICK PULLS OUT IN THE AFTERNOON WITH MUCH OF THE AREA BECOMING DRY SLOTTED UNTIL TROF AXIS CROSSES SATURDAY NIGHT. KEPT POPS GOING FOR THIS REASON AND INSERTED SOME DZ SATURDAY NIGHT WITH EXTENSIVE DRYING ALOFT AMID CLOUT TOPS/OMEGA ONLY REACHING INTO -4 TO -6C RANGE. AS TEMPS COOL...ALLOWED FOR SOME FRZ DZ ON THE RIDGES IN THE MOUNTAINS SATURDAY NIGHT. STILL HAVE SOME SHRA/SHSN IN AS WELL BUT THIS MAY END UP BEING MORE OF A MISTY/DZ SCENARIO. THE LOW STRATUS WILL GRADUALLY SCT OUT ON SUNDAY WITH WAA QUICKLY RETURNING. ANY DZ ENDS IN THE MORNING. WENT A BIT BELOW GUIDANCE ON SUNDAY GIVING SOME NOD TO THE LOW STRATUS FIRST HALF OF THE DAY BENEATH THE INVERSION. && .LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/... COLD FRONT WILL BE EAST OF CWA BY BEGINNING OF THE LONG TERM...WITH COLDER AIR FILTERING IN CHANGING RAIN TO SNOW...ESPECIALLY AT HIGHER ELEVATIONS...AS DEEPER MOISTURE PULLS OUT. UPPER TROUGH PASSES SATURDAY NIGHT...WITH A TRANSITION TO NW FLOW AND MORE UPSLOPE TYPE PRECIP SUNDAY. MODELS HAVE SOME DISAGREEMENT WITH A 500MB TROUGH LATE MONDAY PER GFS OR TUESDAY PER ECMWF. NOT ONLY TIMING DIFFERENCES...BUT GFS KEEPS EVERYTHING NORTH...WHILE ECMWF IS MORE OF A SOUTHERN SOLUTION. WITH UNCERTAINTY IN MODELS STUCK CLOSE TO WPC FROM MONDAY ON. THIS IS CLOSER TO THE ECMWF WITH A DRY DAY MONDAY AND THEN RAIN/SNOW SHOWERS LATE MONDAY NIGHT THROUGH TUESDAY...WITH UPSLOPE SNOW SHOWERS THROUGH WEDNESDAY. ALSO STAYED CLOSE TO WPC FOR TEMPS...IN GENERAL GOING A BIT COLDER THAN PREVIOUS FORECAST. && .AVIATION /17Z THURSDAY THROUGH MONDAY/... UPPER LEVEL TROUGH AND ASSOCIATED VORTICITY MAXIMUM WILL TRAVERSE THE MIDDLE OHIO VALLEY TONIGHT BRINGING GRADUALLY LOWERING CEILINGS THROUGH THE REST OF TODAY AND THE POSSIBILITY OF SOME MIXED PRECIPITATION. NUMERICAL GUIDANCE IS SHOWS DECENT AGREEMENT ON MVFR CEILINGS TONIGHT...ALTHOUGH THE MET GUIDANCE BRINGS THESE CEILINGS DOWN BELOW 2KFT. WILL COMPLY WITH THIS DATA SET AFTER THE PRECIPITATION ENDS...AND KEEP CEILINGS BETWEEN 2KFT AND 3KFT DURING THE PRECIPITATION. PRECIPITATION WILL BEGIN AFTER 03Z FRIDAY. FREEZING RAIN AND SLEET IS A POSSIBILITY...ESPECIALLY FOR THE NORTHERN TERMINALS OF PKB/CKB/EKN. SNOW IS ALSO BRIEFLY POSSIBLE AT THE ONSET. WINDS WILL BE VARIABLE THROUGH 00Z FRIDAY...TURNING SOUTH SOUTHEAST AT 5 TO 10 KNOTS. FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z FRIDAY... FORECAST CONFIDENCE: HIGH UNTIL 06Z. MEDIUM AFTER 06Z. ALTERNATE SCENARIOS: TIMING AND ONSET OF PRECIP MAY VARY. PRECIP TYPE MAY VARY. 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 18 19 20 21 22 23 00 01 02 03 04 05 EST 1HRLY 13 14 15 16 17 18 19 20 21 22 23 00 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 M M 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 M M CKB CONSISTENCY H H H H H H H H H H H H AFTER 18Z FRIDAY... IFR CONDITIONS IN RAIN COULD DEVELOP SATURDAY IN STRONG FLOW ALOFT. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...NONE. OH...NONE. KY...NONE. VA...NONE. && $$ SYNOPSIS...KMC/30 NEAR TERM...KMC/26 SHORT TERM...30 LONG TERM...MZ AVIATION...26
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
649 AM EST THU JAN 9 2014 .SYNOPSIS... A DISTURBANCE WILL BRING A MIX OF PRECIPITATION ACROSS THE AREA TODAY INTO TONIGHT. A STRONGER SYSTEM WILL BEGIN TO BRING RAIN TO THE AREA ON FRIDAY WITH MORE WIDESPREAD RAIN EXPECTED FRIDAY NIGHT INTO SATURDAY. HIGH PRESSURE WILL ALLOW FOR DRY CONDITIONS ON SUNDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... THE HRRR HAS BEEN HANDLING THE PLACEMENT OF THE LIGHT SNOW THE BEST THE PAST SEVERAL HOURS. WENT CLOSELY TO THE HRRR FOR PLACEMENT OF ADDITIONAL LIGHT SNOW OVER THE NEXT FEW HOURS ACROSS PRIMARILY SOUTHERN PORTIONS OF THE FA. THERE WILL BE A BRIEF LULL IN THE PRECIPITATION LATER THIS MORNING BEFORE ADDITIONAL PRECIPITATION ASSOCIATED WITH AN UPPER LEVEL DISTURBANCE BEGINS TO MOVE INTO THE REGION. LIGHT PRECIPITATION WILL BEGIN TO MOVE INTO WESTERN PORTIONS OF THE FA BY THIS AFTERNOON. PRECIPITATION CHANCES WILL SLOWLY INCREASE ACROSS THE FA THIS AFTERNOON AND INTO THE EVENING HOURS. NW PORTIONS OF THE FA ARE EXPECTED TO GET SOME LIGHT SNOW...SE LIGHT RAIN...AND THEN THE CHANCE FOR SOME LIGHT FREEZING RAIN IN BETWEEN. && .SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/... ISENTROPIC LIFT WILL INCREASE ACROSS THE FA THIS EVENING. PRECIPITATION CHANCES WILL INCREASE AND INCREASED PRECIPITATION CHANCES TO THE LIKELY CATEGORY. WENT NON DIURNAL FOR TEMPERATURES THURSDAY NIGHT. LOW TEMPERATURES WILL BE IN THE EVENING HOURS BEFORE SLOWLY RISING A COUPLE OF DEGREES OVERNIGHT THURSDAY NIGHT. PRECIPITATION WILL CONTINUE TO BE A MIX THURSDAY NIGHT. ACCUMULATING SNOW WILL PRIMARILY BE CONFINED TO THE NW HALF OF THE FA WITH AROUND AN INCH OR LESS OF SNOW EXPECTED. MANY LOCATIONS ACROSS CENTRAL AND SOUTHERN PORTIONS OF THE FA HAVE THE POTENTIAL FOR SOME LIGHT FREEZING RAIN AND SUBSEQUENTLY LIGHT ICE ACCUMULATION. ICE ACCUMULATIONS THAT DO OCCUR WILL BE LESS THAN A TENTH OF AN INCH. AS TEMPERATURES SLOWLY RISE THURSDAY NIGHT FREEZING RAIN WILL BECOME LESS OF AN ISSUE FROM SOUTH TO NORTH ACROSS THE AREA. SOME RESIDUAL SHOWER ACTIVITY WILL LINGER INTO THE FRIDAY MORNING HOURS. A MORE POTENT STORM SYSTEM WILL BEGIN TO MOVE INTO THE AREA ON FRIDAY AND BRING WIDESPREAD RAIN TO THE REGION FRIDAY NIGHT INTO SATURDAY. THERE ARE SOME SUBTLE DIFFERENCES IN THE TIMING OF THE MODELS WITH THIS PRECIPITATION HOWEVER MODELS ARE CONSISTENT IN BRINGING UPWARDS OF AN INCH OF RAIN ACROSS THE REGION. COOLER AIR WILL BEGIN TO WORK INTO THE REGION ON SATURDAY AND RAIN WILL TRANSITION BRIEFLY TO LIGHT SNOW ACROSS THE AREA. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... DRY WEATHER IS INDICATED FOR SUNDAY AND MONDAY AS HIGH PRESSURE BUILDS IN FROM THE SOUTHWEST. FOR MONDAY NIGHT AND TUESDAY...RAIN AND SNOW MAY DEVELOP AS LOW PRESSURE TRACKS UP THE EAST COAST. THIS EVENT WOULD AFFECT MAINLY SOUTHEASTERN LOCATIONS CLOSER TO THE SHIELD OF ATLANTIC MOISTURE. SNOW SHOWERS MAY OCCUR TUESDAY NIGHT AND WEDNESDAY IN THE COLDER NORTHWEST FLOW BEHIND THE DEPARTING COASTAL LOW. MODEL TEMPERATURE GUIDANCE SHOWS ABOVE NORMAL HIGHS MAINLY IN THE 40S FOR SUNDAY THROUGH TUESDAY. A SWITCH TO SLIGHTLY BELOW NORMAL HIGHS IN THE 30S IS ANTICIPATED FOR WEDNESDAY IN COLD ADVECTION. && .AVIATION /12Z THURSDAY THROUGH MONDAY/... LOW CLOUDS MAY IMPACT KDAY OVER THE NEXT HOUR OR SO. OTHERWISE EXPECT A MID TO HIGH DECK TO PERSIST. APPEARS THAT SOME LIGHT SNOW COULD DEVELOP OUT DURING THE AFTERNOON AND POTENTIALLY AFFECT KDAY TO KCMH/KLCK FOR A BRIEF PERIOD. BUT BETTER CHANCE OF PRECIPITATION WILL COME AFTER 00Z AREA WIDE AS A DISTURBANCE MOVES ACROSS THE REGION. THIS SHOULD START AS SNOW AT ALL TERMINALS WITH VISIBILITIES DROPPING TO IFR AND CEILINGS TO MVFR. TEMPERATURES MAY WARM JUST ENOUGH FOR PRECIPITATION TO CHANGE TO RAIN BEFORE ENDING WITH THE BEST CHANCE OF THAT OCCURRING IN THE CINCINNATI AREA. ONCE SNOW ENDS VISIBILITIES SHOULD COME UP TO MVFR BUT CEILINGS MAY LOWER BELOW 2000 FT. OUTLOOK...MVFR CEILINGS LIKELY FRIDAY THROUGH SATURDAY NIGHT. MVFR VISIBILITIES POSSIBLE FRIDAY NIGHT AND SATURDAY. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...NONE. KY...NONE. IN...NONE. && $$ SYNOPSIS...NOVAK NEAR TERM...NOVAK SHORT TERM...NOVAK LONG TERM...CONIGLIO AVIATION...
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
427 AM EST THU JAN 9 2014 .SYNOPSIS... A DISTURBANCE WILL BRING A MIX OF PRECIPITATION ACROSS THE AREA TODAY INTO TONIGHT. A STRONGER SYSTEM WILL BEGIN TO BRING RAIN TO THE AREA ON FRIDAY WITH MORE WIDESPREAD RAIN EXPECTED FRIDAY NIGHT INTO SATURDAY. HIGH PRESSURE WILL ALLOW FOR DRY CONDITIONS ON SUNDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... THE HRRR HAS BEEN HANDLING THE PLACEMENT OF THE LIGHT SNOW THE BEST THE PAST SEVERAL HOURS. WENT CLOSELY TO THE HRRR FOR PLACEMENT OF ADDITIONAL LIGHT SNOW OVER THE NEXT FEW HOURS ACROSS PRIMARILY SOUTHERN PORTIONS OF THE FA. THERE WILL BE A BRIEF LULL IN THE PRECIPITATION LATER THIS MORNING BEFORE ADDITIONAL PRECIPITATION ASSOCIATED WITH AN UPPER LEVEL DISTURBANCE BEGINS TO MOVE INTO THE REGION. LIGHT PRECIPITATION WILL BEGIN TO MOVE INTO WESTERN PORTIONS OF THE FA BY THIS AFTERNOON. PRECIPITATION CHANCES WILL SLOWLY INCREASE ACROSS THE FA THIS AFTERNOON AND INTO THE EVENING HOURS. NW PORTIONS OF THE FA ARE EXPECTED TO GET SOME LIGHT SNOW...SE LIGHT RAIN...AND THEN THE CHANCE FOR SOME LIGHT FREEZING RAIN IN BETWEEN. && .SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/... ISENTROPIC LIFT WILL INCREASE ACROSS THE FA THIS EVENING. PRECIPITATION CHANCES WILL INCREASE AND INCREASED PRECIPITATION CHANCES TO THE LIKELY CATEGORY. WENT NON DIURNAL FOR TEMPERATURES THURSDAY NIGHT. LOW TEMPERATURES WILL BE IN THE EVENING HOURS BEFORE SLOWLY RISING A COUPLE OF DEGREES OVERNIGHT THURSDAY NIGHT. PRECIPITATION WILL CONTINUE TO BE A MIX THURSDAY NIGHT. ACCUMULATING SNOW WILL PRIMARILY BE CONFINED TO THE NW HALF OF THE FA WITH AROUND AN INCH OR LESS OF SNOW EXPECTED. MANY LOCATIONS ACROSS CENTRAL AND SOUTHERN PORTIONS OF THE FA HAVE THE POTENTIAL FOR SOME LIGHT FREEZING RAIN AND SUBSEQUENTLY LIGHT ICE ACCUMULATION. ICE ACCUMULATIONS THAT DO OCCUR WILL BE LESS THAN A TENTH OF AN INCH. AS TEMPERATURES SLOWLY RISE THURSDAY NIGHT FREEZING RAIN WILL BECOME LESS OF AN ISSUE FROM SOUTH TO NORTH ACROSS THE AREA. SOME RESIDUAL SHOWER ACTIVITY WILL LINGER INTO THE FRIDAY MORNING HOURS. A MORE POTENT STORM SYSTEM WILL BEGIN TO MOVE INTO THE AREA ON FRIDAY AND BRING WIDESPREAD RAIN TO THE REGION FRIDAY NIGHT INTO SATURDAY. THERE ARE SOME SUBTLE DIFFERENCES IN THE TIMING OF THE MODELS WITH THIS PRECIPITATION HOWEVER MODELS ARE CONSISTENT IN BRINGING UPWARDS OF AN INCH OF RAIN ACROSS THE REGION. COOLER AIR WILL BEGIN TO WORK INTO THE REGION ON SATURDAY AND RAIN WILL TRANSITION BRIEFLY TO LIGHT SNOW ACROSS THE AREA. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... DRY WEATHER IS INDICATED FOR SUNDAY AND MONDAY AS HIGH PRESSURE BUILDS IN FROM THE SOUTHWEST. FOR MONDAY NIGHT AND TUESDAY...RAIN AND SNOW MAY DEVELOP AS LOW PRESSURE TRACKS UP THE EAST COAST. THIS EVENT WOULD AFFECT MAINLY SOUTHEASTERN LOCATIONS CLOSER TO THE SHIELD OF ATLANTIC MOISTURE. SNOW SHOWERS MAY OCCUR TUESDAY NIGHT AND WEDNESDAY IN THE COLDER NORTHWEST FLOW BEHIND THE DEPARTING COASTAL LOW. MODEL TEMPERATURE GUIDANCE SHOWS ABOVE NORMAL HIGHS MAINLY IN THE 40S FOR SUNDAY THROUGH TUESDAY. A SWITCH TO SLIGHTLY BELOW NORMAL HIGHS IN THE 30S IS ANTICIPATED FOR WEDNESDAY IN COLD ADVECTION. && .AVIATION /09Z THURSDAY THROUGH MONDAY/... LIGHT SNOW WILL MOVE EAST OF THE TERMINALS IN THE NEXT HOUR OR SO. THEN VFR CONDITIONS WILL PREVAIL THROUGH 00Z WITH MID TO HIGH CLOUDS PERSISTING. A DISTURBANCE WILL LIFT INTO THE REGION LATE IN THE DAY BRINGING PRECIPITATION AFTER 00Z. THIS WILL LIKELY BE LIGHT SNOW WHICH WOULD DROP VISIBILITIES TO IFR ALONG WITH MVFR CEILINGS. APPEARS THAT TEMPERATURES COULD WARM ENOUGH FOR PRECIPITATION TO CHANGE TO RAIN IN THE CINCINNATI AREA LATE IN THE TAF PERIOD. OUTLOOK...MVFR CEILINGS LIKELY LATE THURSDAY NIGHT THROUGH SATURDAY NIGHT. MVFR VISIBILITIES POSSIBLE FRIDAY NIGHT AND SATURDAY. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...NONE. KY...NONE. IN...NONE. && $$ SYNOPSIS...NOVAK NEAR TERM...NOVAK SHORT TERM...NOVAK LONG TERM...CONIGLIO AVIATION...
AREA FORECAST DISCUSSION
NWS NORMAN OK
1152 AM CST THU JAN 9 2014 .AVIATION... LOW CLOUDS MAY MIX OUT TEMPORARILY IN WESTERN OKLAHOMA THIS AFTERNOON... BUT OTHERWISE WILL LIKELY PERSIST THROUGH THE FORECAST PERIOD WITH MVFR OR MORE LIKELY IFR CONDITIONS. REDUCED VISIBILITIES IN FOG WILL ALSO REDEVELOP OVERNIGHT TONIGHT. THERE WILL BE RAIN CHANCES INCREASING ACROSS THE AREA /ESPECIALLY EAST/ OVERNIGHT INTO TOMORROW MORNING. HAVE INCLUDED RAIN EXPLICITLY IN THE KOKC AND KOUN TAFS... BUT OTHERWISE DID NOT INCLUDE IN THE TAFS WHERE CHANCES ARE LOWER THAN 50 PERCENT AS THE REDUCED VSBY/CIGS IN THE FOG WILL BE THE PRIMARY AVIATION ISSUES. && .PREV DISCUSSION... /ISSUED 1017 AM CST THU JAN 9 2014/ UPDATE... EXTENDED DENSE FOG AND FREEZING FOG ADVISORIES THROUGH 09/18Z. ADJUSTED TEMPS...AND WX. DISCUSSION... AREAS OF FOG AND FREEZING FOG CONTINUE TO PERSIST ACROSS MUCH OF THE REGION. OVERALL... SOME IMPROVEMENT IN VISIBILITIES HAS BEEN OBSERVED... BUT POCKETS OF DENSE FG/FZFG REMAIN. TEMPS CONTINUE TO STRUGGLE UNDER OVERCAST SKIES... HOWEVER... MOST LOCATIONS HAVE SLOWLY CLIMBED ABOVE FREEZING. WITH AT/NEAR FREEZING TEMPS ACROSS NRN/NWRN OK... WHERE FREEZING FOG REMAINS A HAZARD. NUMEROUS ACCIDENTS WERE REPORTED EARLIER THIS MORNING... HOWEVER... CONDITIONS HAVE IMPROVED PER OKDPS TRAFFIC MONITOR... BUT A FEW SLICK SPOTS LIKELY REMAIN. THE HRRR AND RUC SHOW SLOW IMPROVEMENT IN VISIBILITIES THROUGH THE EARLY AFTERNOON... AND THIS SEEMS REASONABLE GIVEN CURRENT TREND AND INCREASING SOUTH WINDS THIS AFTN. THEREFORE... EXTENDED THE DENSE FG AND FZFG ADVISORIES THROUGH 18Z. TRENDED BACK HOURLY TEMPS THIS MORNING/AFTN... GIVEN THE CLOUD COVER...FORECAST WAS RUNNING A TAD WARM COMPARED TO OBS. STILL EXPECT AFTN HIGHS IN THE MID/UPPER 30S TO LOW 40S. JTK PREV DISCUSSION... /ISSUED 525 AM CST THU JAN 9 2014/ DISCUSSION... PLEASE SEE THE AVIATION DISCUSSION BELOW. AVIATION... MAINLY IFR CIGS/VISBYS EXPECTED TODAY WITH THE EXCEPTION OF EARLY THIS MORNING. LIFR FOG AND CIGS ARE CURRENTLY PRESENT OVER MOST TERMINALS. CONDITIONS WILL IMPROVE SLOWLY THROUGHOUT THE DAY WITH VISBYS FIRST COMING UP AROUND 14-15Z AND THEN CIGS IMPROVING A BIT AROUND 18-20Z. WINDS WILL REMAIN LIGHT BECOMING MORE SOUTHERLY BY THIS AFTERNOON. THE WINDS WILL THEN INCREASE LATE TONIGHT AFTER 00Z FROM THE SOUTH AND BRIEF LIFR WILL RETURN DUE TO LOW CIGS/FOG/DRIZZLE. SOME ISOLATED TS WILL ALSO BE POSSIBLE NEAR THE END OF...OR JUST OUTSIDE OF...THIS FORECAST PERIOD MAINLY NEAR OKC/OUN AND PERHAPS LAW/SPS EARLY TOMORROW MORNING. WILL NOT MENTION ANY FOR NOW GIVEN LOW CONFIDENCE. PREV DISCUSSION... /ISSUED 434 AM CST THU JAN 9 2014/ DISCUSSION... WILL CONTINUE WITH ALL HEADLINES THROUGH 9 AM THIS MORNING AS TEMPS HOVER AROUND FREEZING ACROSS MOST OF THE REGION...AND CONTINUE TO SLOWLY FALL ACROSS THE NW AS A SFC RIDGE AXIS SLIDES EAST. SEVERAL SITES REPORTING DENSE FOG RIGHT NOW WEST OF I35...ALONG WITH SOME EARLIER OHP REPORTS...SO FGYS IN GOOD SHAPE TOO. WITH THE EXCEPTION OF THE WEST...VERY LITTLE CLEARING IS EXPECTED TODAY WITH REGARDS TO THE STRATUS SO TEMPS WILL REMAIN IN THE 30S AND 40S FOR MOST LOCATIONS. THE FORECAST HAS CHANGED A BIT FOR FRIDAY WITH THE NEXT EXPECTED SHORTWAVE TROUGH...CURRENTLY SEEN IN WV OVER THE WA/OR BORDER...NOT DIGGING AS FAR SOUTH AS ORIGINALLY ANTICIPATED. HOWEVER...COMBINED LIFT FROM STRONG ISENTROPIC ASCENT AND A SOUTHERN SHORTWAVE TROUGH MOVING OUT OF WEST TEXAS SHOULD MOST DEFINITELY BE ENOUGH TO SUPPORT AT LEAST MORE HEAVY DRIZZLE AND LIGHT RAIN LATE THURS NIGHT INTO EARLY FRIDAY MORNING. THIS WILL ESPECIALLY BE TRUE ACROSS CENTRAL...SOUTHERN AND SE OK. IN ADDITION...A STRONG SWSLY LLJ IS ANTICIPATED AND ASSOCIATED WAA LOOKS LIKE IT WILL NOW SUPPORT MORE ELEVATED INSTABILITY OVER THE SAME AREA. THEREFORE...ISO THUNDERSTORMS ARE MORE LIKELY AND SOME BRIEF HEAVY RAINFALL WILL BE POSSIBLE ACROSS SE/E OK WITHIN BEST MOISTURE AHEAD OF THE MID LEVEL SHORTWAVE TROUGH AXIS FRIDAY AFTERNOON. RAPID CLEARING AND A WEAK COLD FRONT ARE THEN EXPECTED THROUGH THE EVENING HOURS FRIDAY. TEMPS WILL ACTUALLY BE ABOVE NORMAL SAT AFTERNOON WITH CLEAR SKIES AND SHORTWAVE RIDGING OVERHEAD. EVEN WARMER TEMPS WILL DEVELOP SUNDAY WITH DOWNSLOPE LOW TO MID LEVEL SW/W FLOW PRESENT AHEAD OF THE NEXT APPROACHING MID LEVEL SHORTWAVE TROUGH AND WEAK COLD FRONT MOVING OUT OF THE ROCKIES. AGAIN...ONLY EXPECT BRIEF MODIFICATION OF AIRMASS WITH THIS FRONT WITH TEMPS REMAINING SEVERAL DEGREES ABOVE NORMAL MONDAY. THIS TREND WILL CONTINUE THROUGH MID NEXT WEEK...WITH TROUGHING REMAINING OVER THE EASTERN CONUS AND RIDGING OUT WEST. && .PRELIMINARY POINT TEMPS/POPS... OKLAHOMA CITY OK 41 38 56 32 / 10 70 50 0 HOBART OK 41 36 56 29 / 0 20 20 0 WICHITA FALLS TX 44 42 62 32 / 10 50 50 0 GAGE OK 41 32 52 26 / 0 10 10 0 PONCA CITY OK 37 33 51 28 / 10 40 40 0 DURANT OK 43 42 62 37 / 20 90 90 0 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...FREEZING FOG ADVISORY UNTIL NOON CST TODAY FOR OKZ004>007- 009>012-014>018-021-022-024. DENSE FOG ADVISORY UNTIL NOON CST TODAY FOR OKZ023-027-033>036. TX...NONE. && $$ 99/99/01
AREA FORECAST DISCUSSION
NWS NORMAN OK
1017 AM CST THU JAN 9 2014 .UPDATE... EXTENDED DENSE FOG AND FREEZING FOG ADVISORIES THROUGH 09/18Z. ADJUSTED TEMPS...AND WX. && .DISCUSSION... AREAS OF FOG AND FREEZING FOG CONTINUE TO PERSIST ACROSS MUCH OF THE REGION. OVERALL... SOME IMPROVEMENT IN VISIBILITIES HAS BEEN OBSERVED... BUT POCKETS OF DENSE FG/FZFG REMAIN. TEMPS CONTINUE TO STRUGGLE UNDER OVERCAST SKIES... HOWEVER... MOST LOCATIONS HAVE SLOWLY CLIMBED ABOVE FREEZING. WITH AT/NEAR FREEZING TEMPS ACROSS NRN/NWRN OK... WHERE FREEZING FOG REMAINS A HAZARD. NUMEROUS ACCIDENTS WERE REPORTED EARLIER THIS MORNING... HOWEVER... CONDITIONS HAVE IMPROVED PER OKDPS TRAFFIC MONITOR... BUT A FEW SLICK SPOTS LIKELY REMAIN. THE HRRR AND RUC SHOW SLOW IMPROVEMENT IN VISIBILITIES THROUGH THE EARLY AFTERNOON... AND THIS SEEMS REASONABLE GIVEN CURRENT TREND AND INCREASING SOUTH WINDS THIS AFTN. THEREFORE... EXTENDED THE DENSE FG AND FZFG ADVISORIES THROUGH 18Z. TRENDED BACK HOURLY TEMPS THIS MORNING/AFTN... GIVEN THE CLOUD COVER...FORECAST WAS RUNNING A TAD WARM COMPARED TO OBS. STILL EXPECT AFTN HIGHS IN THE MID/UPPER 30S TO LOW 40S. JTK && .PREV DISCUSSION... /ISSUED 525 AM CST THU JAN 9 2014/ DISCUSSION... PLEASE SEE THE AVIATION DISCUSSION BELOW. AVIATION... MAINLY IFR CIGS/VISBYS EXPECTED TODAY WITH THE EXCEPTION OF EARLY THIS MORNING. LIFR FOG AND CIGS ARE CURRENTLY PRESENT OVER MOST TERMINALS. CONDITIONS WILL IMPROVE SLOWLY THROUGHOUT THE DAY WITH VISBYS FIRST COMING UP AROUND 14-15Z AND THEN CIGS IMPROVING A BIT AROUND 18-20Z. WINDS WILL REMAIN LIGHT BECOMING MORE SOUTHERLY BY THIS AFTERNOON. THE WINDS WILL THEN INCREASE LATE TONIGHT AFTER 00Z FROM THE SOUTH AND BRIEF LIFR WILL RETURN DUE TO LOW CIGS/FOG/DRIZZLE. SOME ISOLATED TS WILL ALSO BE POSSIBLE NEAR THE END OF...OR JUST OUTSIDE OF...THIS FORECAST PERIOD MAINLY NEAR OKC/OUN AND PERHAPS LAW/SPS EARLY TOMORROW MORNING. WILL NOT MENTION ANY FOR NOW GIVEN LOW CONFIDENCE. PREV DISCUSSION... /ISSUED 434 AM CST THU JAN 9 2014/ DISCUSSION... WILL CONTINUE WITH ALL HEADLINES THROUGH 9 AM THIS MORNING AS TEMPS HOVER AROUND FREEZING ACROSS MOST OF THE REGION...AND CONTINUE TO SLOWLY FALL ACROSS THE NW AS A SFC RIDGE AXIS SLIDES EAST. SEVERAL SITES REPORTING DENSE FOG RIGHT NOW WEST OF I35...ALONG WITH SOME EARLIER OHP REPORTS...SO FGYS IN GOOD SHAPE TOO. WITH THE EXCEPTION OF THE WEST...VERY LITTLE CLEARING IS EXPECTED TODAY WITH REGARDS TO THE STRATUS SO TEMPS WILL REMAIN IN THE 30S AND 40S FOR MOST LOCATIONS. THE FORECAST HAS CHANGED A BIT FOR FRIDAY WITH THE NEXT EXPECTED SHORTWAVE TROUGH...CURRENTLY SEEN IN WV OVER THE WA/OR BORDER...NOT DIGGING AS FAR SOUTH AS ORIGINALLY ANTICIPATED. HOWEVER...COMBINED LIFT FROM STRONG ISENTROPIC ASCENT AND A SOUTHERN SHORTWAVE TROUGH MOVING OUT OF WEST TEXAS SHOULD MOST DEFINITELY BE ENOUGH TO SUPPORT AT LEAST MORE HEAVY DRIZZLE AND LIGHT RAIN LATE THURS NIGHT INTO EARLY FRIDAY MORNING. THIS WILL ESPECIALLY BE TRUE ACROSS CENTRAL...SOUTHERN AND SE OK. IN ADDITION...A STRONG SWSLY LLJ IS ANTICIPATED AND ASSOCIATED WAA LOOKS LIKE IT WILL NOW SUPPORT MORE ELEVATED INSTABILITY OVER THE SAME AREA. THEREFORE...ISO THUNDERSTORMS ARE MORE LIKELY AND SOME BRIEF HEAVY RAINFALL WILL BE POSSIBLE ACROSS SE/E OK WITHIN BEST MOISTURE AHEAD OF THE MID LEVEL SHORTWAVE TROUGH AXIS FRIDAY AFTERNOON. RAPID CLEARING AND A WEAK COLD FRONT ARE THEN EXPECTED THROUGH THE EVENING HOURS FRIDAY. TEMPS WILL ACTUALLY BE ABOVE NORMAL SAT AFTERNOON WITH CLEAR SKIES AND SHORTWAVE RIDGING OVERHEAD. EVEN WARMER TEMPS WILL DEVELOP SUNDAY WITH DOWNSLOPE LOW TO MID LEVEL SW/W FLOW PRESENT AHEAD OF THE NEXT APPROACHING MID LEVEL SHORTWAVE TROUGH AND WEAK COLD FRONT MOVING OUT OF THE ROCKIES. AGAIN...ONLY EXPECT BRIEF MODIFICATION OF AIRMASS WITH THIS FRONT WITH TEMPS REMAINING SEVERAL DEGREES ABOVE NORMAL MONDAY. THIS TREND WILL CONTINUE THROUGH MID NEXT WEEK...WITH TROUGHING REMAINING OVER THE EASTERN CONUS AND RIDGING OUT WEST. && .PRELIMINARY POINT TEMPS/POPS... OKLAHOMA CITY OK 41 38 56 32 / 10 70 50 0 HOBART OK 41 36 56 29 / 0 20 20 0 WICHITA FALLS TX 44 42 62 32 / 10 50 50 0 GAGE OK 41 32 52 26 / 0 10 10 0 PONCA CITY OK 37 33 51 28 / 10 40 40 0 DURANT OK 43 42 62 37 / 20 90 90 0 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...FREEZING FOG ADVISORY UNTIL NOON CST TODAY FOR OKZ004>007- 009>012-014>018-021-022-024. DENSE FOG ADVISORY UNTIL NOON CST TODAY FOR OKZ023-027-033>036. TX...NONE. && $$
AREA FORECAST DISCUSSION
NWS AMARILLO TX
1115 AM CST THU JAN 9 2014 .AVIATION... VFR CONDITIONS EXPECTED FOR TAF SITES FOR NEXT 24 HOURS. LOW LEVELS SHOULD REMAIN DRY ENOUGH TO PREVENT BR/FG OVERNIGHT. OTHERWISE...WINDS WILL BE SOUTHERLY TONIGHT VEERING TO THE WEST THEN NORTHWEST FRIDAY. && .PREV DISCUSSION... /ISSUED 912 AM CST THU JAN 9 2014/ UPDATE... QUICK UPDATE WAS SENT TO ALLOW THE FREEZING FOG ADVISORY TO EXPIRE AND TO ADJUST SKY/HIGH TEMP GRIDS FOR TODAY. SUNSHINE SHOULD BE ABUNDANT THROUGH EARLY TO MID AFTERNOON BEFORE HIGH CLOUDS START TO MOVE IN AND HIGH TEMPERATURES IN THE WESTERN 2/3RDS OF THE PANHANDLES SHOULD RESPOND NICELY WITH HIGHS WELL INTO THE 50S EXPECTED. PREV DISCUSSION... /ISSUED 726 AM CST THU JAN 9 2014/ UPDATE... HAVE CANCELLED FREEZING FOG ADVISORY FOR CENTRAL CORRIDOR OF FORECAST AREA. FREEZING FOG DEVELOPMENT IS NO LONGER EXPECTED IN THIS AREA. UPDATED TEXT PRODUCTS HAVE BEEN ISSUED. NO OTHER CHANGES TO FORECAST AT THIS TIME. COCKRELL PREV DISCUSSION... /ISSUED 528 AM CST THU JAN 9 2014/ AVIATION... MVFR BR EXPECTED FOR A FEW HOURS AT KAMA AS LIGHT AND VARIABLE SURFACE WINDS PERSIST. BY 16Z...SOUTH SOUTHWEST SURFACE WINDS EXPECTED TO INCREASE...CAUSING ANY REMAINING BR TO DISSIPATE. SURFACE WINDS EXPECTED TO GUST TO AROUND 25 KT TODAY WITH ONLY HIGH-LEVEL CLOUDS EXPECTED. MID- AND HIGH-LEVEL CLOUDS INCREASE OVERNIGHT AS SURFACE WINDS TREND TO WESTERLY. FOLLOWING DISSIPATION OF MORNING BR...VFR CONDITIONS EXPECTED THROUGH 12Z FRIDAY. COCKRELL PREV DISCUSSION... /ISSUED 258 AM CST THU JAN 9 2014/ DISCUSSION... FREEZING FOG SLOW TO MATERIALIZE THIS MORNING...BUT STARTING TO SEE EVIDENCE OF LOW CLOUDS AND FREEZING FOG OFF THE CAPROCK OVER THE EXTREME EASTERN AND SOUTHEASTERN TEXAS PANHANDLE AS OF 08Z TODAY. LATEST HRRR MODEL CONTINUES TO SHOW THE FREEZING FOG SPREADING WEST TO ROUGHLY A GUYMON TO AMARILLO AND CANYON LINE BY 12Z TODAY...AND THEN LIFTING THE FOG AND LOW CLOUDS BY 16Z TO 17Z TODAY. WILL KEEP FREEZING FOG ADVISORY IN PLACE AND EXPIRE THE ADVISORY AT 15Z TODAY. THE FREEZING FOG AND LOW CLOUDS SHOULD GIVE WAY TO SOME SUNSHINE THIS AFTERNOON AS SOUTHWESTERLY WINDS INCREASE TO AROUND 15 TO 20 MPH WITH HIGHER GUSTS. AN UPPER TROUGH DROPPING SOUTHEAST OUT OF THE GREAT BASIN AND CENTRAL ROCKIES TONIGHT SHOULD PUSH ACROSS THE PANHANDLES BY 18Z TO 21Z FRIDAY. MODELS ARE NOW IN AGREEMENT THAT THE UPPER TROUGH WILL COME THROUGH DRY AND USHER IN A COLD FRONT BY FRIDAY AFTERNOON. REMOVED ALL MENTION OF PRECIPITATION FROM THE GRIDS TONIGHT AND FRIDAY. UNSEASONABLY WARM OVER THE WEEKEND WITH DOWNSLOPING SOUTHWESTERLY WINDS INCREASING TO AROUND 15 TO 20 MPH WITH HIGHER GUSTS ON SUNDAY. ANOTHER COLD FRONT TO MOVE THROUGH THE PANHANDLES BY LATE SUNDAY OR SUNDAY NIGHT...FOLLOWED BY ANOTHER COLD FRONT BY NEXT TUESDAY OR WEDNESDAY. CONTINUED UNSEASONABLY WARM CONDITIONS AND DRY THIS WEEKEND THROUGH THE MIDDLE OF NEXT WEEK. SCHNEIDER FIRE WEATHER... ELEVATED FIRE WEATHER CONDITIONS COULD DEVELOP ON FRIDAY MAINLY OVER THE SOUTHWEST PORTION OF THE TEXAS PANHANDLE AS 20 FOOT WINDS INCREASE TO AROUND 15 TO 20 MPH WITH HIGHER GUSTS BY FRIDAY AFTERNOON AND MINIMUM AFTERNOON RELATIVE HUMIDITIES FALL TO AROUND 15 TO 20 PERCENT. ON SUNDAY...20 FOOT WINDS WILL INCREASE TO AROUND 15 TO 20 OR 25 MPH WITH HIGHER GUSTS AS MINIMUM AFTERNOON RELATIVE HUMIDITIES FALL TO AROUND 10 TO 20 PERCENT. ELEVATED FIRE WEATHER CONDITIONS MAY DEVELOP OVER PORTIONS OF THE PANHANDLES SUNDAY. SCHNEIDER && .AMA WATCHES/WARNINGS/ADVISORIES... TX...NONE. OK...NONE. && $$ 07/09
AREA FORECAST DISCUSSION...UPDATED
NWS AMARILLO TX
912 AM CST THU JAN 9 2014 .UPDATE... QUICK UPDATE WAS SENT TO ALLOW THE FREEZING FOG ADVISORY TO EXPIRE AND TO ADJUST SKY/HIGH TEMP GRIDS FOR TODAY. SUNSHINE SHOULD BE ABUNDANT THROUGH EARLY TO MID AFTERNOON BEFORE HIGH CLOUDS START TO MOVE IN AND HIGH TEMPERATURES IN THE WESTERN 2/3RDS OF THE PANHANDLES SHOULD RESPOND NICELY WITH HIGHS WELL INTO THE 50S EXPECTED. && .PREV DISCUSSION... /ISSUED 726 AM CST THU JAN 9 2014/ UPDATE... HAVE CANCELLED FREEZING FOG ADVISORY FOR CENTRAL CORRIDOR OF FORECAST AREA. FREEZING FOG DEVELOPMENT IS NO LONGER EXPECTED IN THIS AREA. UPDATED TEXT PRODUCTS HAVE BEEN ISSUED. NO OTHER CHANGES TO FORECAST AT THIS TIME. COCKRELL PREV DISCUSSION... /ISSUED 528 AM CST THU JAN 9 2014/ AVIATION... MVFR BR EXPECTED FOR A FEW HOURS AT KAMA AS LIGHT AND VARIABLE SURFACE WINDS PERSIST. BY 16Z...SOUTH SOUTHWEST SURFACE WINDS EXPECTED TO INCREASE...CAUSING ANY REMAINING BR TO DISSIPATE. SURFACE WINDS EXPECTED TO GUST TO AROUND 25 KT TODAY WITH ONLY HIGH-LEVEL CLOUDS EXPECTED. MID- AND HIGH-LEVEL CLOUDS INCREASE OVERNIGHT AS SURFACE WINDS TREND TO WESTERLY. FOLLOWING DISSIPATION OF MORNING BR...VFR CONDITIONS EXPECTED THROUGH 12Z FRIDAY. COCKRELL PREV DISCUSSION... /ISSUED 258 AM CST THU JAN 9 2014/ DISCUSSION... FREEZING FOG SLOW TO MATERIALIZE THIS MORNING...BUT STARTING TO SEE EVIDENCE OF LOW CLOUDS AND FREEZING FOG OFF THE CAPROCK OVER THE EXTREME EASTERN AND SOUTHEASTERN TEXAS PANHANDLE AS OF 08Z TODAY. LATEST HRRR MODEL CONTINUES TO SHOW THE FREEZING FOG SPREADING WEST TO ROUGHLY A GUYMON TO AMARILLO AND CANYON LINE BY 12Z TODAY...AND THEN LIFTING THE FOG AND LOW CLOUDS BY 16Z TO 17Z TODAY. WILL KEEP FREEZING FOG ADVISORY IN PLACE AND EXPIRE THE ADVISORY AT 15Z TODAY. THE FREEZING FOG AND LOW CLOUDS SHOULD GIVE WAY TO SOME SUNSHINE THIS AFTERNOON AS SOUTHWESTERLY WINDS INCREASE TO AROUND 15 TO 20 MPH WITH HIGHER GUSTS. AN UPPER TROUGH DROPPING SOUTHEAST OUT OF THE GREAT BASIN AND CENTRAL ROCKIES TONIGHT SHOULD PUSH ACROSS THE PANHANDLES BY 18Z TO 21Z FRIDAY. MODELS ARE NOW IN AGREEMENT THAT THE UPPER TROUGH WILL COME THROUGH DRY AND USHER IN A COLD FRONT BY FRIDAY AFTERNOON. REMOVED ALL MENTION OF PRECIPITATION FROM THE GRIDS TONIGHT AND FRIDAY. UNSEASONABLY WARM OVER THE WEEKEND WITH DOWNSLOPING SOUTHWESTERLY WINDS INCREASING TO AROUND 15 TO 20 MPH WITH HIGHER GUSTS ON SUNDAY. ANOTHER COLD FRONT TO MOVE THROUGH THE PANHANDLES BY LATE SUNDAY OR SUNDAY NIGHT...FOLLOWED BY ANOTHER COLD FRONT BY NEXT TUESDAY OR WEDNESDAY. CONTINUED UNSEASONABLY WARM CONDITIONS AND DRY THIS WEEKEND THROUGH THE MIDDLE OF NEXT WEEK. SCHNEIDER FIRE WEATHER... ELEVATED FIRE WEATHER CONDITIONS COULD DEVELOP ON FRIDAY MAINLY OVER THE SOUTHWEST PORTION OF THE TEXAS PANHANDLE AS 20 FOOT WINDS INCREASE TO AROUND 15 TO 20 MPH WITH HIGHER GUSTS BY FRIDAY AFTERNOON AND MINIMUM AFTERNOON RELATIVE HUMIDITIES FALL TO AROUND 15 TO 20 PERCENT. ON SUNDAY...20 FOOT WINDS WILL INCREASE TO AROUND 15 TO 20 OR 25 MPH WITH HIGHER GUSTS AS MINIMUM AFTERNOON RELATIVE HUMIDITIES FALL TO AROUND 10 TO 20 PERCENT. ELEVATED FIRE WEATHER CONDITIONS MAY DEVELOP OVER PORTIONS OF THE PANHANDLES SUNDAY. SCHNEIDER && .AMA WATCHES/WARNINGS/ADVISORIES... TX...NONE. OK...NONE. && $$ 07/09
AREA FORECAST DISCUSSION...UPDATED
NWS AMARILLO TX
726 AM CST THU JAN 9 2014 .UPDATE... HAVE CANCELLED FREEZING FOG ADVISORY FOR CENTRAL CORRIDOR OF FORECAST AREA. FREEZING FOG DEVELOPMENT IS NO LONGER EXPECTED IN THIS AREA. UPDATED TEXT PRODUCTS HAVE BEEN ISSUED. NO OTHER CHANGES TO FORECAST AT THIS TIME. COCKRELL && .PREV DISCUSSION... /ISSUED 528 AM CST THU JAN 9 2014/ AVIATION... MVFR BR EXPECTED FOR A FEW HOURS AT KAMA AS LIGHT AND VARIABLE SURFACE WINDS PERSIST. BY 16Z...SOUTH SOUTHWEST SURFACE WINDS EXPECTED TO INCREASE...CAUSING ANY REMAINING BR TO DISSIPATE. SURFACE WINDS EXPECTED TO GUST TO AROUND 25 KT TODAY WITH ONLY HIGH-LEVEL CLOUDS EXPECTED. MID- AND HIGH-LEVEL CLOUDS INCREASE OVERNIGHT AS SURFACE WINDS TREND TO WESTERLY. FOLLOWING DISSIPATION OF MORNING BR...VFR CONDITIONS EXPECTED THROUGH 12Z FRIDAY. COCKRELL PREV DISCUSSION... /ISSUED 258 AM CST THU JAN 9 2014/ DISCUSSION... FREEZING FOG SLOW TO MATERIALIZE THIS MORNING...BUT STARTING TO SEE EVIDENCE OF LOW CLOUDS AND FREEZING FOG OFF THE CAPROCK OVER THE EXTREME EASTERN AND SOUTHEASTERN TEXAS PANHANDLE AS OF 08Z TODAY. LATEST HRRR MODEL CONTINUES TO SHOW THE FREEZING FOG SPREADING WEST TO ROUGHLY A GUYMON TO AMARILLO AND CANYON LINE BY 12Z TODAY...AND THEN LIFTING THE FOG AND LOW CLOUDS BY 16Z TO 17Z TODAY. WILL KEEP FREEZING FOG ADVISORY IN PLACE AND EXPIRE THE ADVISORY AT 15Z TODAY. THE FREEZING FOG AND LOW CLOUDS SHOULD GIVE WAY TO SOME SUNSHINE THIS AFTERNOON AS SOUTHWESTERLY WINDS INCREASE TO AROUND 15 TO 20 MPH WITH HIGHER GUSTS. AN UPPER TROUGH DROPPING SOUTHEAST OUT OF THE GREAT BASIN AND CENTRAL ROCKIES TONIGHT SHOULD PUSH ACROSS THE PANHANDLES BY 18Z TO 21Z FRIDAY. MODELS ARE NOW IN AGREEMENT THAT THE UPPER TROUGH WILL COME THROUGH DRY AND USHER IN A COLD FRONT BY FRIDAY AFTERNOON. REMOVED ALL MENTION OF PRECIPITATION FROM THE GRIDS TONIGHT AND FRIDAY. UNSEASONABLY WARM OVER THE WEEKEND WITH DOWNSLOPING SOUTHWESTERLY WINDS INCREASING TO AROUND 15 TO 20 MPH WITH HIGHER GUSTS ON SUNDAY. ANOTHER COLD FRONT TO MOVE THROUGH THE PANHANDLES BY LATE SUNDAY OR SUNDAY NIGHT...FOLLOWED BY ANOTHER COLD FRONT BY NEXT TUESDAY OR WEDNESDAY. CONTINUED UNSEASONABLY WARM CONDITIONS AND DRY THIS WEEKEND THROUGH THE MIDDLE OF NEXT WEEK. SCHNEIDER FIRE WEATHER... ELEVATED FIRE WEATHER CONDITIONS COULD DEVELOP ON FRIDAY MAINLY OVER THE SOUTHWEST PORTION OF THE TEXAS PANHANDLE AS 20 FOOT WINDS INCREASE TO AROUND 15 TO 20 MPH WITH HIGHER GUSTS BY FRIDAY AFTERNOON AND MINIMUM AFTERNOON RELATIVE HUMIDITIES FALL TO AROUND 15 TO 20 PERCENT. ON SUNDAY...20 FOOT WINDS WILL INCREASE TO AROUND 15 TO 20 OR 25 MPH WITH HIGHER GUSTS AS MINIMUM AFTERNOON RELATIVE HUMIDITIES FALL TO AROUND 10 TO 20 PERCENT. ELEVATED FIRE WEATHER CONDITIONS MAY DEVELOP OVER PORTIONS OF THE PANHANDLES SUNDAY. SCHNEIDER && .PRELIMINARY POINT TEMPS/POPS... AMARILLO TX 50 28 51 24 58 / 0 10 5 0 0 BEAVER OK 43 25 47 25 57 / 0 5 5 0 0 BOISE CITY OK 49 26 49 22 55 / 0 5 5 0 0 BORGER TX 49 30 53 27 55 / 0 5 5 0 0 BOYS RANCH TX 54 29 52 23 57 / 0 5 5 0 0 CANYON TX 50 28 52 23 59 / 0 10 5 0 0 CLARENDON TX 48 31 56 26 59 / 0 10 10 0 0 DALHART TX 51 23 48 23 56 / 0 5 5 0 0 GUYMON OK 47 28 47 21 55 / 0 5 5 0 0 HEREFORD TX 54 28 53 23 59 / 0 5 5 0 0 LIPSCOMB TX 45 30 50 25 56 / 0 5 10 0 0 PAMPA TX 47 29 50 24 56 / 0 10 10 0 0 SHAMROCK TX 46 32 55 27 58 / 0 10 10 0 0 WELLINGTON TX 45 33 56 26 60 / 0 10 10 0 0 && .AMA WATCHES/WARNINGS/ADVISORIES... TX...FREEZING FOG ADVISORY UNTIL 9 AM CST THIS MORNING FOR THE FOLLOWING ZONES: COLLINGSWORTH...DONLEY...GRAY...HEMPHILL... LIPSCOMB...OCHILTREE...ROBERTS...WHEELER. OK...FREEZING FOG ADVISORY UNTIL 9 AM CST THIS MORNING FOR THE FOLLOWING ZONES: BEAVER. && $$ 03/11
AREA FORECAST DISCUSSION...UPDATED
NWS AMARILLO TX
528 AM CST THU JAN 9 2014 .AVIATION... MVFR BR EXPECTED FOR A FEW HOURS AT KAMA AS LIGHT AND VARIABLE SURFACE WINDS PERSIST. BY 16Z...SOUTH SOUTHWEST SURFACE WINDS EXPECTED TO INCREASE...CAUSING ANY REMAINING BR TO DISSIPATE. SURFACE WINDS EXPECTED TO GUST TO AROUND 25 KT TODAY WITH ONLY HIGH-LEVEL CLOUDS EXPECTED. MID- AND HIGH-LEVEL CLOUDS INCREASE OVERNIGHT AS SURFACE WINDS TREND TO WESTERLY. FOLLOWING DISSIPATION OF MORNING BR...VFR CONDITIONS EXPECTED THROUGH 12Z FRIDAY. COCKRELL && .PREV DISCUSSION... /ISSUED 258 AM CST THU JAN 9 2014/ DISCUSSION... FREEZING FOG SLOW TO MATERIALIZE THIS MORNING...BUT STARTING TO SEE EVIDENCE OF LOW CLOUDS AND FREEZING FOG OFF THE CAPROCK OVER THE EXTREME EASTERN AND SOUTHEASTERN TEXAS PANHANDLE AS OF 08Z TODAY. LATEST HRRR MODEL CONTINUES TO SHOW THE FREEZING FOG SPREADING WEST TO ROUGHLY A GUYMON TO AMARILLO AND CANYON LINE BY 12Z TODAY...AND THEN LIFTING THE FOG AND LOW CLOUDS BY 16Z TO 17Z TODAY. WILL KEEP FREEZING FOG ADVISORY IN PLACE AND EXPIRE THE ADVISORY AT 15Z TODAY. THE FREEZING FOG AND LOW CLOUDS SHOULD GIVE WAY TO SOME SUNSHINE THIS AFTERNOON AS SOUTHWESTERLY WINDS INCREASE TO AROUND 15 TO 20 MPH WITH HIGHER GUSTS. AN UPPER TROUGH DROPPING SOUTHEAST OUT OF THE GREAT BASIN AND CENTRAL ROCKIES TONIGHT SHOULD PUSH ACROSS THE PANHANDLES BY 18Z TO 21Z FRIDAY. MODELS ARE NOW IN AGREEMENT THAT THE UPPER TROUGH WILL COME THROUGH DRY AND USHER IN A COLD FRONT BY FRIDAY AFTERNOON. REMOVED ALL MENTION OF PRECIPITATION FROM THE GRIDS TONIGHT AND FRIDAY. UNSEASONABLY WARM OVER THE WEEKEND WITH DOWNSLOPING SOUTHWESTERLY WINDS INCREASING TO AROUND 15 TO 20 MPH WITH HIGHER GUSTS ON SUNDAY. ANOTHER COLD FRONT TO MOVE THROUGH THE PANHANDLES BY LATE SUNDAY OR SUNDAY NIGHT...FOLLOWED BY ANOTHER COLD FRONT BY NEXT TUESDAY OR WEDNESDAY. CONTINUED UNSEASONABLY WARM CONDITIONS AND DRY THIS WEEKEND THROUGH THE MIDDLE OF NEXT WEEK. SCHNEIDER FIRE WEATHER... ELEVATED FIRE WEATHER CONDITIONS COULD DEVELOP ON FRIDAY MAINLY OVER THE SOUTHWEST PORTION OF THE TEXAS PANHANDLE AS 20 FOOT WINDS INCREASE TO AROUND 15 TO 20 MPH WITH HIGHER GUSTS BY FRIDAY AFTERNOON AND MINIMUM AFTERNOON RELATIVE HUMIDITIES FALL TO AROUND 15 TO 20 PERCENT. ON SUNDAY...20 FOOT WINDS WILL INCREASE TO AROUND 15 TO 20 OR 25 MPH WITH HIGHER GUSTS AS MINIMUM AFTERNOON RELATIVE HUMIDITIES FALL TO AROUND 10 TO 20 PERCENT. ELEVATED FIRE WEATHER CONDITIONS MAY DEVELOP OVER PORTIONS OF THE PANHANDLES SUNDAY. SCHNEIDER && .PRELIMINARY POINT TEMPS/POPS... AMARILLO TX 50 28 51 24 58 / 0 10 5 0 0 BEAVER OK 43 25 47 25 57 / 0 5 5 0 0 BOISE CITY OK 49 26 49 22 55 / 0 5 5 0 0 BORGER TX 49 30 53 27 55 / 0 5 5 0 0 BOYS RANCH TX 54 29 52 23 57 / 0 5 5 0 0 CANYON TX 50 28 52 23 59 / 0 10 5 0 0 CLARENDON TX 48 31 56 26 59 / 0 10 10 0 0 DALHART TX 51 23 48 23 56 / 0 5 5 0 0 GUYMON OK 47 28 47 21 55 / 0 5 5 0 0 HEREFORD TX 54 28 53 23 59 / 0 5 5 0 0 LIPSCOMB TX 45 30 50 25 56 / 0 5 10 0 0 PAMPA TX 47 29 50 24 56 / 0 10 10 0 0 SHAMROCK TX 46 32 55 27 58 / 0 10 10 0 0 WELLINGTON TX 45 33 56 26 60 / 0 10 10 0 0 && .AMA WATCHES/WARNINGS/ADVISORIES... TX...FREEZING FOG ADVISORY UNTIL 9 AM CST THIS MORNING FOR THE FOLLOWING ZONES: ARMSTRONG...CARSON...COLLINGSWORTH... DONLEY...GRAY...HANSFORD...HEMPHILL...HUTCHINSON... LIPSCOMB...MOORE...OCHILTREE...POTTER...RANDALL...ROBERTS... SHERMAN...WHEELER. OK...FREEZING FOG ADVISORY UNTIL 9 AM CST THIS MORNING FOR THE FOLLOWING ZONES: BEAVER...TEXAS. && $$ 03/11
AREA FORECAST DISCUSSION
NWS AMARILLO TX
258 AM CST THU JAN 9 2014 .DISCUSSION... FREEZING FOG SLOW TO MATERIALIZE THIS MORNING...BUT STARTING TO SEE EVIDENCE OF LOW CLOUDS AND FREEZING FOG OFF THE CAPROCK OVER THE EXTREME EASTERN AND SOUTHEASTERN TEXAS PANHANDLE AS OF 08Z TODAY. LATEST HRRR MODEL CONTINUES TO SHOW THE FREEZING FOG SPREADING WEST TO ROUGHLY A GUYMON TO AMARILLO AND CANYON LINE BY 12Z TODAY...AND THEN LIFTING THE FOG AND LOW CLOUDS BY 16Z TO 17Z TODAY. WILL KEEP FREEZING FOG ADVISORY IN PLACE AND EXPIRE THE ADVISORY AT 15Z TODAY. THE FREEZING FOG AND LOW CLOUDS SHOULD GIVE WAY TO SOME SUNSHINE THIS AFTERNOON AS SOUTHWESTERLY WINDS INCREASE TO AROUND 15 TO 20 MPH WITH HIGHER GUSTS. AN UPPER TROUGH DROPPING SOUTHEAST OUT OF THE GREAT BASIN AND CENTRAL ROCKIES TONIGHT SHOULD PUSH ACROSS THE PANHANDLES BY 18Z TO 21Z FRIDAY. MODELS ARE NOW IN AGREEMENT THAT THE UPPER TROUGH WILL COME THROUGH DRY AND USHER IN A COLD FRONT BY FRIDAY AFTERNOON. REMOVED ALL MENTION OF PRECIPITATION FROM THE GRIDS TONIGHT AND FRIDAY. UNSEASONABLY WARM OVER THE WEEKEND WITH DOWNSLOPING SOUTHWESTERLY WINDS INCREASING TO AROUND 15 TO 20 MPH WITH HIGHER GUSTS ON SUNDAY. ANOTHER COLD FRONT TO MOVE THROUGH THE PANHANDLES BY LATE SUNDAY OR SUNDAY NIGHT...FOLLOWED BY ANOTHER COLD FRONT BY NEXT TUESDAY OR WEDNESDAY. CONTINUED UNSEASONABLY WARM CONDITIONS AND DRY THIS WEEKEND THROUGH THE MIDDLE OF NEXT WEEK. SCHNEIDER && .FIRE WEATHER... ELEVATED FIRE WEATHER CONDITIONS COULD DEVELOP ON FRIDAY MAINLY OVER THE SOUTHWEST PORTION OF THE TEXAS PANHANDLE AS 20 FOOT WINDS INCREASE TO AROUND 15 TO 20 MPH WITH HIGHER GUSTS BY FRIDAY AFTERNOON AND MINIMUM AFTERNOON RELATIVE HUMIDITIES FALL TO AROUND 15 TO 20 PERCENT. ON SUNDAY...20 FOOT WINDS WILL INCREASE TO AROUND 15 TO 20 OR 25 MPH WITH HIGHER GUSTS AS MINIMUM AFTERNOON RELATIVE HUMIDITIES FALL TO AROUND 10 TO 20 PERCENT. ELEVATED FIRE WEATHER CONDITIONS MAY DEVELOP OVER PORTIONS OF THE PANHANDLES SUNDAY. SCHNEIDER && .PRELIMINARY POINT TEMPS/POPS... AMARILLO TX 50 28 51 24 58 / 0 10 5 0 0 BEAVER OK 43 25 47 25 57 / 0 5 5 0 0 BOISE CITY OK 49 26 49 22 55 / 0 5 5 0 0 BORGER TX 49 30 53 27 55 / 0 5 5 0 0 BOYS RANCH TX 54 29 52 23 57 / 0 5 5 0 0 CANYON TX 50 28 52 23 59 / 0 10 5 0 0 CLARENDON TX 48 31 56 26 59 / 0 10 10 0 0 DALHART TX 51 23 48 23 56 / 0 5 5 0 0 GUYMON OK 47 28 47 21 55 / 0 5 5 0 0 HEREFORD TX 54 28 53 23 59 / 0 5 5 0 0 LIPSCOMB TX 45 30 50 25 56 / 0 5 10 0 0 PAMPA TX 47 29 50 24 56 / 0 10 10 0 0 SHAMROCK TX 46 32 55 27 58 / 0 10 10 0 0 WELLINGTON TX 45 33 56 26 60 / 0 10 10 0 0 && .AMA WATCHES/WARNINGS/ADVISORIES... TX...FREEZING FOG ADVISORY UNTIL 9 AM CST THIS MORNING FOR THE FOLLOWING ZONES: ARMSTRONG...CARSON...COLLINGSWORTH... DONLEY...GRAY...HANSFORD...HEMPHILL...HUTCHINSON... LIPSCOMB...MOORE...OCHILTREE...POTTER...RANDALL...ROBERTS... SHERMAN...WHEELER. OK...FREEZING FOG ADVISORY UNTIL 9 AM CST THIS MORNING FOR THE FOLLOWING ZONES: BEAVER...TEXAS. && $$ 03/11
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
1144 PM CST WED JAN 8 2014 .AVIATION... IFR CEILINGS IMPACTING KCDS WILL LIKELY DETERIORATE TO LIFR SHORTLY AFTER MIDNIGHT AS LOW LEVEL MOISTURE REMAINS IN PLACE COUPLED WITH DECREASING WINDS UNDERNEATH PRESSURE RISES. UNCERTAINTY STILL EXISTS AS TO WHETHER CEILINGS WILL DEVELOP AS FAR WEST AS KLBB...SO WILL KEEP PREVAILING VFR CONDITIONS IN THE FORECAST FOR NOW. SKIES WILL CLEAR LATE MORNING TO EARLY AFTERNOON THURSDAY AS WINDS TURN SOUTHERLY. BE CAUTIOUS OF ICING POTENTIAL TONIGHT THROUGHOUT THE LOWEST COUPLE THOUSAND FEET. && PREV DISCUSSION... /ISSUED 247 PM CST WED JAN 8 2014/ SHORT TERM... AFTER A BRIEF PERIOD OF NEAR ZONAL FLOW AHEAD OF AN UPPER LEVEL DISTURBANCE FLOW WILL VEER NWRLY FOR ABOUT 12 HOURS THIS EVENING THEN SWING AROUND TO SOUTHWESTERLY LATE THURSDAY AS ARCING UPPER LEVEL TROUGH APPROACHES FROM THE WEST. THE INITIAL DISTURBANCE...WHILE INDICATING OPEN ON OBJECTIVE AND MODEL ANALYSIS...APPEARS TO BE WEAKLY CLOSED ON WV IMAGERY THUS SUGGESTING THAT THE STRENGTH OF THE FEATURE MAY BE A BIT STRONGER THAN THE MODELS ARE SUGGESTING. WHILE THIS FIRST DISTURBANCE WILL NOT OFFER ANY RAINFALL...IT LIKELY WILL HELP THE MOIST ADVECTION TO OUR EAST WHICH IS ALREADY EXTENDING TO SRN KS. THE RAP WOULD APPEAR TO HAVE THE BEST HANDLE ON LOW LEVEL MOISTURE ATTM THOUGH ALL NWP SOLUTIONS INDICATE A WRAP-AROUND MORPHOLOGY ACROSS THE NORTHERN PANHANDLE. GIVEN THE OBSERVATIONAL EVIDENCE AND AMALGAMATING THE VARIOUS SOLUTIONS...CURRENT FORECAST THINKING WOULD BRING LOW CLOUDS INTO AT LEAST THE NORTHEASTERN THIRD OF THE FA OVERNIGHT AND PERHAPS AFFECTING THE NWRN ZONES AS WELL. AN ATTENDANT RISK OF PATCHY FOG WILL EXIST ACROSS THE ROLLING PLAINS THURSDAY MORNING WITH SKIES CLEARING THEREAFTER AHEAD OF THE NEXT SYSTEM. LONG TERM... MODEL TRENDS ARE LOOKING INCREASINGLY GRIMM FOR PRECIPITATION CHANCES ACROSS THE REGION FROM THURSDAY NIGHT INTO FRIDAY MORNING. CHANCES FOR PRECIPITATION HOWEVER HAVE NOT DIMINISHED FOR AREAS EAST OF THE FA EXTENDING INTO THE ROLLING PLAINS. MAXIMUM HEIGHT FALLS ARE TRENDING FARTHER NORTH WITH THIS SHARP TROUGH. ALTHOUGH THE NAM CONTINUES TO SHOW THE DOWNSTREAM UPPER LEVEL JET STREAK OVER THE AREA...THE GFS AND ECMWF SHOW A MORE EASTWARD POSITION ALONG WITH ITS ASSOCIATED UPPER LEVEL DIVERGENCE. FRONTOGENETICAL LIFT DURING THE DAY ON FRIDAY WILL BE TOO LATE TO INTERACT WITH THE UPPER LEVEL TROUGH THIS FAR WEST. ISENTROPIC LIFT WILL INCREASE THROUGH THE NIGHTTIME INTO EARLY FRIDAY MORNING BUT THE BEST LIFT WILL BE ACROSS NORTH TEXAS INTO OKLAHOMA. WEAK ELEVATED INSTABILITY ON FRIDAY MORNING MAY GENERATE SOME ISOLATED THUNDER WITHIN RAIN SHOWER ACTIVITY. THIS TROUGH WILL BE FOLLOWED BY STRONG SUBSIDENCE IN ITS WAKE ON FRIDAY ALONG WITH STRONG DOWNGLIDE ON THE ISENTROPIC SURFACES. A COLD FRONT WILL THEN FOLLOW ON FRIDAY AFTERNOON UNDER DRY NORTHWEST FLOW ALOFT. THE NEXT WAVE WILL ENTER THE PICTURE FROM SUNDAY NIGHT INTO MONDAY ALTHOUGH THERE ARE STILL CONSIDERABLE DIFFERENCES BETWEEN THE GFS AND ECMWF SOLUTIONS. THE ECMWF IS STILL MUCH SHARPER WITH THIS TROUGH DROPPING THROUGH THE NORTHWEST FLOW BUT WILL HAVE LITTLE MOISTURE TO WORK WITH. A FEW GFS ENSEMBLE MEMBERS ARE ALSO INDICATING A SIMILAR SOLUTION. ONE THING THESE MODELS DO AGREE UPON ARE STRONG WINDS ON SUNDAY AFTERNOON. ANALOG GUIDANCE DOES SHOW A POSSIBILITY FOR STRONG SURFACE WINDS WITH STRONG WINDS ALOFT SPREADING IN FROM THE NORTH. AFTER MONDAY...THE UPPER RIDGE WILL HIT THE GYM AND BECOME PUMPED UP OVER THE WEST COAST WITH A RETURN TO DRY NORTHWEST FLOW FOR WEST TEXAS. && .PRELIMINARY POINT TEMPS/POPS... FRIONA 48 18 58 30 54 / 0 0 0 20 0 TULIA 44 20 53 34 56 / 0 0 0 40 10 PLAINVIEW 48 21 53 36 57 / 0 0 0 40 10 LEVELLAND 53 22 54 38 58 / 0 0 0 40 10 LUBBOCK 53 22 53 38 59 / 0 0 0 50 10 DENVER CITY 53 26 55 39 58 / 0 0 0 40 10 BROWNFIELD 54 24 55 39 58 / 0 0 0 40 10 CHILDRESS 44 24 48 37 56 / 0 0 0 60 40 SPUR 53 26 52 40 61 / 0 0 0 60 30 ASPERMONT 53 29 52 44 63 / 0 0 0 70 50 && .LUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 31
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
520 PM CST FRI JAN 10 2014 .SHORT TERM...(TONIGHT THROUGH SATURDAY NIGHT) ISSUED AT 206 PM CST FRI JAN 10 2014 MAIN CONCERNS IN THE SHORT TERM WILL BE DEALING WITH WINTRY MIX INTO TONIGHT. A WINTER WEATHER ADVISORY IS IN EFFECT UNTIL 6 AM SATURDAY. WATER VAPOR IMAGERY SHOWING A DEEP MID-LEVEL TROUGH MOVING ACROSS CENTRAL CONUS AT THIS TIME. AT THE SURFACE...A TROUGH EXTENDED FROM ALONG THE DAKOTAS/MN BORDER...INTO EASTERN NEBRASKA/KANSAS. THESE FEATURES WERE PRODUCING ISENTROPIC LIFT AND MOISTURE TRANSPORT INTO THE AREA FOR A WINTRY MIX OF PRECIPITATION AT GROUND LEVEL. RADAR SHOWING RETURNS ACROSS THE ENTIRE AREA WITH AREAS OF MAINLY DRIZZLE AND FREEZING DRIZZLE BEING REPORTED. SOME SLEET WAS ALSO SHOWING UP ACROSS PARTS OF NORTHEAST IA. OTHERWISE...TEMPERATURES ACROSS THE AREA RANGED FROM THE MIDDLE 20S ACROSS NORTH CENTRAL WI...TO THE LOWER 30S ACROSS NORTHEAST IA INTO FAR SOUTHWEST WI. LOOK FOR THE MID-LEVEL/SURFACE TROUGH TO MOVE EAST THROUGH THE AREA TONIGHT...WITH MOST OF THE PRECIPITATION CHANGING OVER TO LIGHT SNOW THIS EVENING. THE ONLY EXCEPTION WILL BE ACROSS PORTIONS OF NORTHEAST IA INTO FAR SOUTHWEST AND CENTRAL WI WHERE THERE WILL BE LACK OF ICE ISSUES IN THE COLUMN AND WARMER AIR ALOFT. SO...A MIXTURE OF DRIZZLE...FREEZING DRIZZLE...SLEET AND LIGHT SNOW WILL STILL BE POSSIBLE THERE. WHERE THE SNOW FALLS...GENERALLY ALONG AND NORTHWEST OF A TOMAH/LA CROSSE/OELWEIN LINE...PERHAPS 1/2-1 INCH IS POSSIBLE. OF NOTE IS THE RAP SHOWING LOSS OF ICE IN THE CLOUD AGAIN AFTER MIDNIGHT...HINTING AT THE POSSIBILITY OF MIXING WITH OR CHANGING OVER TO LIGHT FREEZING DRIZZLE OVERNIGHT. WITH THIS IN MIND...WILL KEEP WINTER WEATHER ADVISORY GOING THROUGH 6 AM SATURDAY. OVERNIGHT LOWS ARE EXPECTED TO DIP INTO THE 20S. MAY STILL BE SOME LIGHT SNOW/FLURRY ACTIVITY EARLY ON SATURDAY MORNING...BUT LOOKING FOR ANY LINGERING PRECIPITATION TO SHIFT OFF TO THE EAST BY NOON AS A RIDGE OF HIGH PRESSURE BUILDS IN FROM THE PLAINS. AREAS WEST OF THE MISSISSIPPI WILL LIKELY SEE A GOOD AMOUNT OF SUNSHINE BY AFTERNOON WITH CLEARING PUSHING EAST OF THE MISSISSIPPI LATER IN THE AFTERNOON. HIGHS ON SATURDAY EXPECTED TO RISE INTO THE UPPER 20S TO LOWER 30S. RIDGE OF HIGH PRESSURE WILL CONTINUE TO MOVE EAST ACROSS THE AREA SATURDAY NIGHT FOR QUIET WEATHER CONDITIONS. WILL SEE SOME INCREASE IN MID/HIGH LEVEL CLOUDS THOUGH AHEAD OF A WARM FRONT PUSHING EAST OUT OF THE NORTHERN/CENTRAL PLAINS. OVERNIGHT LOWS WILL BE IN THE LOWER TO MIDDLE TEENS. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 206 PM CST FRI JAN 10 2014 MILDER PACIFIC ORIGIN AIR WILL PUSH INTO THE AREA ON SUNDAY WITH HIGHS EXPECTED TO TOP OFF IN THE LOWER/MIDDLE 30S. UNFORTUNATELY... INCREASING CLOUD COVER AND SOUTHWEST WINDS IN THE 10 TO 20 MPH RANGE WILL MAKE IT FEEL MORE LIKE THE LOWER/MIDDLE 20S. A COLD FRONT WILL THEN PUSH INTO/THROUGH THE AREA SUNDAY NIGHT. THIS WILL GIVE THE AREA A CHANCE OF A WINTRY MIX WITH A TRICKY THERMAL PROFILE IN PLACE. COLDER AIR UNDERCUTTING RELATIVELY MILDER AIR ALOFT MAY PRODUCE A LIGHT WINTRY MIX OF FREEZING RAIN/SLEET/SNOW AS OVERNIGHT LOWS FALL INTO THE TEENS/LOWER 20S. FORTUNATELY... PRECIPITATION LOOKS VERY LIGHT...BUT ANY FREEZING PRECIPITATION COULD CAUSE HEADACHES. WILL CONTINUE TO TO KEEP A CLOSE EYE ON THIS. COLDER AIR WILL FILTER INTO AREA MONDAY THROUGH TUESDAY AS A DEEP MID-LEVEL TROUGH CARVES OUT OVER THE CENTRAL CONUS. SOME EMBEDDED ENERGY WITHIN THE TROUGH WILL GIVE THE AREA A CHANCE FOR LIGHT SNOW AS WELL. LOOK FOR HIGHS MONDAY AND TUESDAY IN THE 20S WITH LOWS MONDAY NIGHT IN THE UPPER SINGLE DIGITS AND TEENS. ANOTHER SHOT AT SOME LIGHT SNOW LOOKS TO OCCUR WEDNESDAY NIGHT INTO THURSDAY AS WARM AIR ADVECTION TAKES PLACE AHEAD OF LOW PRESSURE MOVING ACROSS SOUTHERN CANADA. SOME LINGERING LIGHT SNOW OF FLURRY CHANCES WILL BE SEEN THURSDAY NIGHT AS THE COLD FRONT FROM THIS LOW PASSES THROUGH. MUCH COLDER AIR IS ON TAP GOING INTO FRIDAY AS ANOTHER MODIFIED SHOT OF ARCTIC AIR MAKES ITS WAY INTO THE AREA. HIGHS ARE EXPECTED TO DROP BACK INTO THE TEENS. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY NIGHT) ISSUED AT 520 PM CST FRI JAN 10 2014 PCPN WILL CONTINUE TO BE A FACTOR IN THE AVIATION FORECAST THROUGH THE EVENING HOURS...WITH A LOSS OF ICE IN THE CLOUD - PER BUFKIT SOUNDINGS - RESULTING IN PERIODS OF -FZDZ IN ADDITION TO -SN. THIS IS EVIDENCED VIA SFC OBS AND SATELLITE IMAGERY. MESO MODELS POINT TO MOST OF THE PCPN EXITING EAST BY 06Z. SUB 1 KFT CIGS SHOULD REMAIN PREDOMINANT THROUGH THE NIGHT TIME HOURS...WITH A GRADUAL INCREASE SAT MORNING. SHARP CUT OFF FROM CLOUD TO CLEAR EVIDENT IN RECENT SATELLITE IMAGERY...AND SKIES COULD GO FROM OVC TO SCT/SKC IN A SHORT PERIOD OF TIME. NOT ANTICIPATING THIS UNTIL LATER SAT AFTERNOON. FRONTAL PASSAGE WILL TURN WINDS TO THE WEST/NORTHWEST LATER THIS EVENING...AND TIGHT PRESSURE GRADIENT AND SOME CLEARING COULD LEAD TO HIGHER GUSTS SAT AFTERNOON. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...WINTER WEATHER ADVISORY UNTIL 6 AM CST SATURDAY FOR WIZ017-029- 034-041>044-053>055-061. MN...WINTER WEATHER ADVISORY UNTIL 6 AM CST SATURDAY FOR MNZ096. IA...WINTER WEATHER ADVISORY UNTIL 6 AM CST SATURDAY FOR IAZ010-011- 029-030. && $$ SHORT TERM...DAS LONG TERM....DAS AVIATION.....RIECK
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
411 PM CST THU JAN 9 2014 .SHORT TERM... TONIGHT AND FRIDAY MORNING...FORECAST CONFIDENCE MEDIUM. A MID LEVEL SHORTWAVE OVER CENTRAL IL THIS AFTERNOON WILL SHIFT EASTWARD THIS EVENING. WEAK LOW LEVEL WARM AIR ADVECTION AND ISENTROPIC LIFT OVER SOUTHERN WISCONSIN WITH THIS SHORTWAVE WILL EXIT SOUTHEAST WI BY LATE EVENING AS WELL...AND THE AREA OF LIGHT SNOW IN THE MILWAUKEE TO KENOSHA AREA WILL DIMINISH. ORIGINALLY WE WERE THINKING IT WOULD BE FREEZING DRIZZLE THIS AFTERNOON...BUT THE LOW LAYER AIR IS COOL ENOUGH TO DEVELOP ICE CRYSTALS AND THAT/S WHY WE/RE SEEING SNOW. THE ONLY FORCING LEFT AFTER MIDNIGHT FOR LOW CLOUDS AND POSSIBLE PATCHY FOG OR FREEZING DRIZZLE WILL BE IN THE LOWEST LAYERS...WHICH NAM AND RAP FCST SOUNDINGS SHOW THAT LAYER TO BE VERY SHALLOW...LESS THAN 5000 FEET. THEREFORE...WE COULD SEE A FEW BREAKS IN THE CLOUDS LATE TONIGHT. TEMPERATURES WILL DROP SLIGHTLY DURING THE EVENING AND THEN STAY STEADY OR GRADUALLY RISE THROUGH THE REST OF THE NIGHT. ON FRIDAY...A STRONGER SHORTWAVE WILL BE ROUNDING THE BASE OF A MID LEVEL TROUGH IN THE MORNING...THEN EJECTING INTO THE MIDWEST DURING THE AFTERNOON AND EVENING. SURFACE LOW PRESSURE DEVELOPING OVER THE CENTRAL PLAINS WILL SWING UP INTO SOUTHERN WISCONSIN BY FRIDAY EVENING. INCREASING LOW LEVEL WARM AIR ADVECTION AND ISENTROPIC LIFT WILL HELP TO SATURATE LOW LEVELS A LITTLE HIGHER IN THE MORNING...THUS A CHANCE FOR SOME FREEZING DRIZZLE. THE NAM AND CANADIAN MODELS ARE SLOWER WITH THIS MOISTURE RETURN THAN THE GFS AND ECMWF. MEANWHILE...WE WILL ALSO BE SATURATING FROM THE TOP DOWN...AND STRONG WARMING WILL BE OCCURRING AT 850-700MB. IT WILL BE A MATTER OF WHEN THE WHOLE COLUMN CAN SATURATE BEFORE RAIN OR FREEZING RAIN CAN FULLY DEVELOP. IN THE MEANTIME...THERE WILL BE A CHANCE FOR FREEZING DRIZZLE OR SLEET. FRIDAY AFTERNOON THROUGH SUNDAY...FORECAST CONFIDENCE MEDIUM MIXED PCPN...MAINLY RAIN OR FREEZING RAIN WILL DEVELOP NORTH AND OVERSPREAD THE CWA FRI AFT AND CONTINUE INTO THE EVENING AS WARM ADVECTION INCREASES VIA THE LEFT EXIT REGION OF A LOW LEVEL JET AS WELL AS THE APPROACH AND PASSAGE OF AN AMPLIFYING SHORTWAVE TROUGH. THE SFC LOW WILL TRACK FROM SE IA TO ERN LOWER MI FROM THE AFTERNOON THROUGH 12Z SAT AND DEEPEN FROM 997 MB TO 990 MB. SFC TEMPS TO RISE ABOVE FREEZING WITH A WARM LAYER ALOFT HOWEVER A FROZEN GROUND AND ROADS CAN STILL BECOME ICY. WENT WITH A WINTER WEATHER ADVISORY OVER SOUTH CENTRAL WI WHERE TEMPS WILL HOVER CLOSER TO THE FREEZING MARK VERSUS SLIGHTLY MILDER CONDITIONS OVER SE WI. THE INITIAL BAND OF PCPN COULD BE FREEZING RAIN OVER ALL OF SRN WI INITIALLY WITH TEMPS QUICKLY WARMING OVER SE WI AND ONLY RAIN EXPECTED. THE RAIN AND FREEZING RAIN WILL THEN CHANGE TO LIGHT SNOW WITH THE COLD FRONTAL PASSAGE. AROUND INCH OF SNOW IS EXPECTED OVER SOUTH CENTRAL WI...BUT MAINLY NORTH AND WEST OF MADISON WHERE COOLER TEMPS AT THE SFC AND ALOFT ARE EXPECTED. LIGHTER PCPN IS EXPECTED FOR THE LATE EVENING AND OVERNIGHT AS A DRY SLOT MOVES OVERHEAD. BRISK WLY WINDS AND COLD ADVECTION TO PREVAIL ON SAT FOLLOWED BY THE PASSAGE OF A SFC RIDGE SAT NT. COOLER TEMPS ARE EXPECTED BUT STILL ABOVE NORMAL. A PROGRESSIVE JET STREAM WILL BRING ANOTHER ROUND OF SLY WINDS...WARM ADVECTION...AND CHANCES OF MIXED PCPN FOR MAINLY SUN NT. .LONG TERM... MONDAY THROUGH THURSDAY...FORECAST CONFIDENCE MEDIUM NW FLOW TO PREVAIL WITH WEAK SYNOPTIC LOWS AND CHANCES OF LGT SNOW AFFECTING THE REGION FOR MON NT INTO TUE AND AGAIN ON THU. TEMPS TO BE AROUND OR SLIGHTLY ABOVE NORMAL. && .AVIATION/00Z TAFS/... VFR WITH INTERMITTENT MVFR CIGS ACROSS SOUTH CENTRAL AND SOUTHEAST WI THIS AFTERNOON. EXPECT AREA OF MVFR AND FUEL ALT TOWARD WEST CENTRAL WI TO SPREAD SOUTHEAST THIS EVENING. ONCE THOSE LOWER CEILINGS MOVE IN...NOT SURE IF THEY WILL GET OUT OF HERE OVERNIGHT OR IF THEY WILL JUST HANG AROUND THROUGH FRIDAY AFTERNOON. LIGHT SNOW IN SOUTHEAST WI EXPECTED TO EXIT BY LATE EVENING. GLOW LEVEL MOISTURE WILL CONTINUE TO INCREASE FRIDAY MORNING. THERE IS A SMALL CHANCE FOR FREEZING DRIZZLE IN THE MORNING...BUT QUESTIONABLE ABOUT DEEP ENOUGH LOW LEVEL MOISTURE. PATCHY FOG WILL ACCOMPANY THE WARMER...MOISTER AIR AS WELL. RAIN WILL BEGIN FRIDAY AFTERNOON...SPREADING FROM SOUTH TO NORTH. KEEP AN EYE ON PAVEMENT TEMPERATURES AS WELL AS SURFACE TEMPERATURES TO DETERMINE IF IT WILL FREEZE ONTO VARIOUS SURFACES. IT WILL BE HIGHLY VARIABLE ACROSS THE AREA. && .MARINE... LOW PRESSURE DEVELOPING IN THE PLAINS WILL RESULT IN GRADUALLY TIGHTENING PRESSURE GRADIENT TONIGHT INTO FRIDAY. EXPECTING WIND GUSTS TO EXCEED 22 KNOTS FRIDAY INTO SATURDAY AS LOW PRESSURE MOVES FROM THE CENTRAL PLAINS INTO WISCONSIN. HIGH RESOLUTION VSBL SATELLITE IMAGERY FROM WED REVEALS EXTENSIVE ICE COVER COVERING MAJORITY OF NEARSHORE WATERS. INCREASING SOUTH WINDS AND WARMER TEMPERATURES MAY CAUSE THE ICE TO BREAK UP A BIT OVER THE WEEKEND. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...WINTER WEATHER ADVISORY FROM NOON FRIDAY TO 6 AM CST SATURDAY FOR WIZ056-062-063-067. WINTER WEATHER ADVISORY FROM 3 PM FRIDAY TO 6 AM CST SATURDAY FOR WIZ046-047-057. LM...NONE. && $$ TONIGHT/FRIDAY AND AVIATION/MARINE...MRC FRIDAY NIGHT THROUGH THURSDAY...GEHRING
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
1203 PM CST THU JAN 9 2014 .UPDATE... TEMPERATURES ARE RISING QUICKLY INTO THE TEENS EARLY THIS AFTERNOON. AN AREA OF LOW CLOUDS ARE SPREADING NORTHWARD INTO SOUTHERN WISCONSIN...BUT THERE IS A BREAK TO THE SOUTH OF THIS BAND. NO FREEZING DRIZZLE OR SNOW SIGNALS WITH THIS INITIAL SHALLOW BAND. WEAK WARM AIR ADVECTION AND ISENTROPIC LIFT WILL LEAD TO LOW CLOUDS OVER SOUTHERN WI THROUGH LATE EVENING. RAP SOUNDINGS FROM THIS MORNING ARE SHOWING A SLIGHTLY COOLER SATURATED COLUMN FROM SFC TO 10KFT OVER FAR SOUTHERN WI THIS AFTERNOON AND EVENING WHICH WOULD SUGGEST A BETTER CHANCE FOR SNOW RATHER THAN FREEZING DRIZZLE. OBS IN CENTRAL/NORTHERN IL ARE SHOWING SNOW AT THIS TIME. THE WEAK SHORTWAVE OVER IL RESPONSIBLE FOR LOW CLOUDS AND WAA OVER SOUTHERN WI TODAY/THIS EVENING WILL SHIFT OFF TO THE EAST AFTER MIDNIGHT. WE COULD SEE SOME BREAKS IN THE CLOUDS LATE TONIGHT. && .AVIATION/18Z TAFS/...MVFR CIGS SPREADING INTO SOUTHERN WI SHOULD ONLY BE TEMPORARY AND MOVE OUT LATE IN THE AFTERNOON. ANOTHER ROUND OF LOW CLOUDS WITH DEEPER MOISTURE WILL SPREAD IN THIS EVENING AND HANG THROUGH THE NIGHT...POSSIBLY DEVELOPING BREAKS AFTER MIDNIGHT. GOOD CHANCE FOR MVFR CIGS THIS EVENING AND FUEL ALTERNATE CIGS LATE TONIGHT THROUGH FRIDAY MORNING AS LOW LEVEL MOISTURE CONTINUES TO INCREASE. THERE WILL ALSO BE A SMALL CHANCE FOR SOME -ZL OR LIGHT SNOW. PATCHY FOG WILL ACCOMPANY THE WARMER...MOISTER AIR AS WELL. && .PREV DISCUSSION... /ISSUED 348 AM CST THU JAN 9 2014/ TODAY...FORECAST CONFIDENCE...MEDIUM. WINDS WILL REMAIN MOSTLY BELOW 4 KNOTS THROUGH THE EARLY MORNING AS TEMPERATURES REMAIN IN THE BITTER COLD -5 TO -20 DEGREE RANGE. AS WINDS BEGIN TO INCREASE AFTER 14Z...EXPECT TEMPERATURES TO WARM RAPIDLY ENOUGH TO AVOID A PROLONGED PERIOD OF WIND CHILLS OF -20 OR COLDER. HENCE WL HOLD OFF ON WIND CHILL ADVY...BUT WILL REISSUE SPS FOR BITTER COLD TEMPERATURES AND LOCALIZED WIND CHILL VALUES THIS MORNING. TEMPERATURES SHOULD WARM QUICKLY TO ABOVE ZERO ONCE CLOUDS TO THE SOUTH AND WEST ADVANCE INTO SOUTHERN WI. BOTH AREAS OF CLOUDS BEING CAUSED BY WEAK MID-LEVEL SHORT WAVES AND SURGING WARM AIR ADVECTION TO THE EAST AND NORTH. LAYER Q-VECTOR CONVERGENCE AND ISENTROPIC OMEGA WITH BOTH WEAK SYSTEMS REMAIN TO THE NORTH AND SOUTH OF SOUTHERN WISCONSIN. HOWEVER AREA TO THE SOUTH HAS A BIT MORE LAYER MOISTURE TO WORK WITH AND LOWER LATE AFTERNOON CONDENSATION PRESSURE DEFICITS. CONTINUE SMALL CHANCE FOR LIGHT PRECIP IN SOUTH LATER THIS AFTN. MAY BE SOME VERY LIGHT SNOW OR FREEZING DRIZZLE AS LATE AFTN FORECAST SOUNDINGS SHOWING LESS THAN 70 PERCENT CHANCE FOR ICE CRYSTAL INITIATION IN CLOUD LAYER. TONIGHT...FORECAST CONFIDENCE...MEDIUM. LOWER CONDENSATION PRESSURE DEFICITS AND WEAK OMEGA JUST TO THE SOUTH MOVES OFF TO THE EAST DURING THE EVENING. HENCE WL REMOVE LOW POPS AFTER THE EVENING IN THE SOUTHEAST. HOWEVER THICKENING LOW LEVEL MOISTURE RIDING OVER COLD SURFACE AND WEAK LOW LEVEL WARM AIR ADVECTION MAY BE JUST ENOUGH TO TRIGGER SOME PATCHY FOG...FLURRIES AND FREEZING DRIZZLE. NOT EXPECTING ANY ACCUMULATION. TEMPERATURES LIKELY TO REMAIN STEADY OR RISE FOR MOST OF THE NIGHT. FRIDAY AND SATURDAY...FORECAST CONFIDENCE...MEDIUM LOW PRESSURE WILL APPROACH FRIDAY...MOVING THROUGH FRIDAY EVENING AND OVERNIGHT. THIS WILL BRING WIDESPREAD PRECIPITATION TO SOUTHERN WISCONSIN...WITH PRECIPITABLE WATER VALUES EXPECTED TO BE ABOUT 2 STANDARD DEVIATIONS HIGHER THAN NORMAL FOR THIS TIME OF YEAR. AS THE LOW LEVELS SATURATE EARLY FRIDAY...SOUNDINGS INDICATING THE SATURATION MAY NOT BE DEEP/COLD ENOUGH FOR ICE CRYSTAL FORMATION. THUS WENT WITH MAINLY FREEZING RAIN/DRIZZLE IN THE MORNING...AS SURFACE TEMPERATURES WILL STILL BE BELOW FREEZING. SURFACE TEMPS AND TEMPS ALOFT WILL CONTINUE TO RISE THROUGH THE DAY...WITH ALL RAIN EXPECTED ACROSS THE SOUTHEAST HALF OF THE FORECAST AREA BY LATE AFTERNOON. COULD SEE ANYTHING FROM RAIN...FREEZING RAIN...SLEET...OR SNOW FARTHER NORTHWEST. HARD TO NAIL DOWN AT THIS POINT GIVEN SOME DIFFERENCES AMONG MODEL TEMPERATURES...SO KEPT A GENERAL MIX. LOOKS LIKE TEMPERATURES SHOULD BEGIN TO COOL WEST TO EAST BY LATE FRIDAY EVENING...WITH PRECIP LIKELY TRANSITIONING FROM RAIN TO SNOW OVERNIGHT INTO SATURDAY MORNING. BEST CHANCE FOR ANY ACCUMULATIONS WILL BE MAINLY ACROSS THE NORTHWEST HALF OF THE FORECAST AREA...AS THE BULK OF MOISTURE WILL HAVE MOVED OUT BY THE TIME THE SOUTHEAST COOLS ENOUGH FOR SNOW. COULD SEE A COUPLE INCHES NORTHWEST...PARTICULARLY IF LATEST ECMWF/GFS/CANADIAN ARE RIGHT WITH DEFORMATION SNOW MOVING THROUGH SATURDAY MORNING. SUNDAY THROUGH WEDNESDAY...FORECAST CONFIDENCE...LOW LOOKS LIKE A COUPLE SHORTWAVES WILL ROLL THROUGH SUNDAY THROUGH TUESDAY...SO KEPT SOME POPS GOING. NOT VERY GOOD MODEL AGREEMENT WITH TIMING OR THE TEMPERATURE PROFILE...SO CONFIDENCE STILL ON THE LOW SIDE WITH THE SPECIFICS FOR NOW. WENT WITH CONSENSUS OF SOLUTIONS...RESULTING IN TEMPS REMAINING A FEW DEGREES ABOVE NORMAL ALONG WITH A CHANCE FOR RAIN/SNOW. LOOKS DRIER AND COLDER WEDNESDAY. AVIATION/12Z TAFS/...EXPECT INCREASING CLOUDS THIS MORNING POSSIBLY REACHING MVFR LEVELS LATER TODAY. GOOD CHANCE FOR LOWER CIGS TONIGHT AS LOW LEVEL MOISTURE CONTINUES TO INCREASE. THERE WILL ALSO BE A SMALL CHANCE FOR SOME -ZL. PATCHY FOG WILL ACCOMPANY THE WARMER...MOISTER AIR AS WELL. MARINE...LIGHT WEST WINDS WILL TURN TO THE SOUTH AND INCREASE TODAY AS HIGH PRESSURE MOVES OFF TO THE EAST. DEVELOPING LOW PRESSURE TROUGH IN THE PLAINS WILL RESULT IN GRADUALLY TIGHTENING PRESSURE GRADIENT LATER TODAY INTO FRIDAY. WIND GUSTS MAY BRIEFLY REACH SMALL CRAFT LEVELS LATE TODAY AND THIS EVENING BUT NOT ENOUGH CONFIDENCE IN ENOUGH OF A PROLONGED PERIOD TO HOIST SMALL CRAFT AT THIS TIME. BETTER CHANCE LATER FRIDAY INTO SATURDAY AS LOW PRESSURE MOVES FROM THE CENTRAL PLAINS INTO WISCONSIN. HIGH RESOLUTION VSBL SATELLITE IMAGERY FROM WED REVEALS EXTENSIVE ICE COVER COVERING MAJORITY OF NEARSHORE WATERS. INCREASING SOUTH WINDS AND WARMER TEMPERATURES MAY CAUSE THE ICE TO BREAK UP A BIT OVER THE WEEKEND. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...NONE. LM...NONE. && $$ UPDATE...MRC TODAY/TONIGHT AND AVIATION/MARINE...MBK FRIDAY THROUGH WEDNESDAY...DDV
AREA FORECAST DISCUSSION...UPDATED
NWS CHARLESTON SC
452 AM EST SAT JAN 11 2014 ...SEVERE THUNDERSTORMS POSSIBLE THIS AFTERNOON AND EVENING... .SYNOPSIS... A STRONG COLD FRONT WILL SWEEP ACROSS THE REGION THIS EVENING. HIGH PRESSURE WILL BUILD SUNDAY AND QUICKLY MOVE OFF THE COAST MONDAY...BEFORE ANOTHER COLD FRONT MOVES THROUGH THE AREA BY TUESDAY MORNING. HIGH PRESSURE WILL REBUILD DURING THE MIDDLE OF NEXT WEEK...WITH YET ANOTHER COLD FRONT APPROACHING BY FRIDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... THROUGH SUNRISE...VISIBILITIES CONTINUE TO IMPROVE AWAY FROM THE COAST THIS MORNING AS BOUNDARY LAYER WINDS INCREASE. VISIBILITIES HAVE INCREASED ABOVE ADVISORY THRESHOLDS FOR MUCH OF THE INTERIOR... SO THE DENSE FOG ADVISORY HAS BEEN CANCELLED FOR THOSE AREAS. AT THE COAST...DENSE SEA FOG CONTINUES TO MOVE INLAND. VISIBILITIES HAVE RAPIDLY DECREASED ACROSS MUCH OF THE CHARLESTON METRO AREA OVER THE PAST HOUR AND AREA WEBCAMS SUGGEST VISIBILITIES ARE NEAR ZERO AT TIMES. OPTED TO EXPAND THE DENSE FOG ADVISORY TO INCLUDE TIDAL BERKELEY AND CHARLESTON COUNTIES TO ACCOUNT FOR GOING TRENDS. DENSE SEA FOG WILL LINGER ACROSS ALL COASTAL ZONES... INCLUDING INLAND CHATHAM AND THE SAVANNAH METRO AREA...FOR SEVERAL MORE HOURS. A POTENTIALLY ACTIVE DAY IS ON TAP FOR SOUTHEAST SOUTH CAROLINA AND SOUTHEAST GEORGIA AS A COLD FRONT APPROACHES FROM THE WEST. AHEAD OF THE FRONT...INCREASING WARM AIR ADVECTION BEING DRIVEN BY A STRONG PRE-FRONTAL LOW-LEVEL JET WILL HELP PUSH TEMPERATURES INTO THE LOWER TO MID 70S FOR MOST AREAS AWAY FROM THE COAST... WHICH IS ABOUT 10-15 DEGREES ABOVE NORMAL. AS WARM AIR ADVECTION INTENSIFIES...ISOLATED TO SCATTERED SHOWERS WILL LIKELY BREAKOUT AND AFFECT PORTIONS OF THE AREA PRIOR TO THE ARRIVAL OF THE MAIN CONVECTIVE LINE. ATTM IT APPEARS THE MAIN CONVECTIVE LINE...POSSIBLY IN THE FORM OF A STRONG/SEVERE QUASI-LINEAR CONVECTIVE SYSTEM /QLCS/...WILL REACH THE FAR WESTERN ZONES BY EARLY AFTERNOON AND REACH THE COAST BY LATE AFTERNOON OR EARLY THIS EVENING. INSTABILITY PROGS AND MODIFIED POINT SOUNDINGS SUGGEST SBCAPE VALUES WILL RISE TO 800-1000 J/KG WITH LIFTED INDICES DROPPING AS LOW AS -4C. ALTHOUGH MID-LEVEL LAPSE RATES WILL BE POOR...HEALTHY 0-6KM BULK SHEAR OF 50-60 KT INDUCED BY STRONG LOW-LEVEL JETTING COUPLED WITH MODEST INSTABILITY WILL SUPPORT A RISK FOR SEVERE TSTMS WITHIN A TYPICAL MID-JANUARY HIGH SHEAR/LOW CAPE ENVIRONMENT. THE PRIMARY HAZARD RIGHT NOW LOOK TO BE DAMAGING WINDS WITH A RISK FOR ISOLATED TORNADOES WHERE DISCRETE CELLS OR EMBEDDED MESO-VORTICES WITHIN BOWING CONVECTIVE SEGMENTS CAN DEVELOP. RAP 0-1KM HELICITY VALUES INCREASE TO NEAR 300 M2/S2 AND THE HIGH SHEAR/LOW CAPE SHERBS3 TORNADO PARAMETER RISES ABOVE THE BENCH MARK OF 1 UNIT FOR MUCH OF THE AREA...ALL SUGGESTING THERE IS A REASONABLE RISK FOR TORNADOES. FOR TODAY...WILL HIGHLIGHT POPS NEAR 100 PERCENT FOR ALL AREAS WITH THE HIGHEST GRIDDED POPS PLACED WITH THE EXPECTED TIMING/PLACEMENT OF THE EXPECTED CONVECTIVE LINE. HIGHS WILL BE IN THE LOWER TO MID 70S UNDER MAINLY CLOUDY SKIES. WILL INCLUDE DAMAGING WIND AND TORNADO ATTRIBUTES IN ALL GRIDDED AND TEXT PRODUCTS AND HIGHLIGHT A POTENTIAL FOR SEVERE TSTMS IN THE HAZARDOUS WEATHER OUTLOOK. THE WINDOW OF GREATEST SEVERE THREAT LOOKS TO BE 1 PM THROUGH 7 PM. && .SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/... TONIGHT...CONDITIONS WILL RAPIDLY IMPROVE THIS EVENING AS THE PRIMARY CONVECTIVE LINE PUSHES OFFSHORE AND THE COLD FRONT MOVES THROUGH. EXPECT CLEARING TO OCCUR DURING THE EVENING HOURS WITH MAINLY CLEAR SKIES DEVELOPING BY MIDNIGHT...IF NOT SOONER. LOWS WILL RANGE FROM THE LOWER 40S WELL INLAND TO THE UPPER 40S AT THE BEACHES. SUNDAY...DRY HIGH PRESSURE WILL BUILD IN THE WAKE OF THE DEPARTING COLD FRONT...YET PROGRESSIVE FLOW ALOFT WILL PULL THE CENTER OF THE HIGH QUICKLY TOWARD THE NEARBY ATLANTIC WATERS. COLD ADVECTION WILL BE WEAK BEHIND THE FRONT...AND WITH WIND DIRECTIONS REMAINING GENERALLY WEST/SOUTHWEST...EXPECT ONLY A SLIGHT COOLING TREND TO OCCUR. HIGH TEMPERATURES IN THE MID TO UPPER 60S WILL BE COOLER THAN THE PREVIOUS DAY...YET STILL BE WELL ABOVE SEASONAL NORMALS. AN AMPLIFYING LONG WAVE TROUGH ACROSS THE CENTRAL PLAINS AFTER MIDNIGHT WILL SUPPORT BRIEF DOWNSTREAM HEIGHT RISES...AND WHEN COMBINED WITH WARM ADVECTION WITHIN BACKING LOW LEVEL FLOW...LOW TEMPERATURES IN THE UPPER 30S INLAND TO LOW 40S NEAR THE COAST WILL ALSO BE SEVERAL DEGREES WARMER THAN AVERAGE. MONDAY...SOUTHERN STREAM SHORTWAVE ENERGY TRACKING ACROSS THE GULF OF MEXICO WILL SPIN UP A SURFACE WAVE ALONG THE WESTERN PERIPHERY OF THE RETREATING ATLANTIC HIGH PRESSURE. THERE REMAINS NOTABLE DISAGREEMENT BETWEEN MODEL SOLUTIONS REGARDING THE STRENGTH AND TRACK OF THIS LOW PRESSURE WAVE AND TRAILING FRONT AS THEY PROGRESS TOWARD THE FORECAST AREA THROUGH THE DAY. IN GENERAL...A SOLID TAP INTO GULF MOISTURE WILL SUPPORT A SWATH OF PRECIPITATION ASSOCIATED WITH THE SYSTEM...AND EXPECT RAIN CHANCES TO INCREASE FROM SOUTHWEST TO NORTHEAST DURING THE LATE AFTERNOON TO EVENING TIME FRAME. WARM ADVECTION AND PRE-FRONTAL COMPRESSION WILL SUPPORT TEMPERATURES PEAKING IN THE MID TO UPPER 60S...EVEN AS CLOUD COVER GRADUALLY INCREASES. THE BEST RAIN POTENTIAL ACTUALLY APPEARS TO OCCUR OVERNIGHT INTO EARLY TUESDAY MORNING..AS THE SURFACE LOW LIFTS NORTH/NORTHEAST AND PULLS THE FRONT INTO THE REGION. LOW TEMPERATURES WILL BE QUITE MILD AS A RESULT...ONLY FALLING INTO THE UPPER 40S TO AROUND 50 DEGREES. TUESDAY...THE SYNOPTIC PATTERN REMAINS A BIT UNSETTLED EVEN AFTER THE FRONT MOVES OFFSHORE...WITH ANOTHER LARGE AREA OF UPPER LEVEL ENERGY SWEEPING SOUTHEAST FROM THE GREAT LAKES REGION. RAIN CHANCES WILL DECREASE DURING THE MORNING HOURS BEHIND THE DEPARTING COLD FRONT. HOWEVER DRY SURFACE HIGH PRESSURE IN ITS WAKE WILL BECOME SUPPRESSED TO THE SOUTH...AS YET ANOTHER FRONT DRIVEN BY THE AMPLIFYING UPPER SHORTWAVE DESCENDS FROM THE OHIO VALLEY LATE IN THE DAY. ONCE AGAIN...DOWNSLOPE FLOW AND THE LACK OF SOLID COLD ADVECTION WILL SUPPORT ABOVE NORMAL HIGH TEMPERATURES IN THE MID 60S. && .LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/... THE DEEPENING UPPER TROUGH WILL SHIFT OVER THE EAST COAST STATES ON WEDNESDAY...WITH A DRY COLD FRONT MOVING ACROSS THE REGION EARLY IN THE DAY. THERE APPEARS TO BE MORE NOTABLE COLD ADVECTION BEHIND THIS FRONT...AND EXPECT HIGH TEMPERATURES TO BE SUPPRESSED IN THE MID 50S UNDER MOSTLY CLEAR SKIES ON WEDNESDAY. LOW TEMPERATURES WEDNESDAY NIGHT WILL BE THE COLDEST SEEN IN DAYS...AS LIGHT WINDS AND LITTLE TO NO CLOUD COVER SET UP IDEAL RADIATIONAL COOLING CONDITIONS. A NEARLY ZONAL UPPER PATTERN ON THURSDAY WILL BE RATHER TRANSIENT...AS BROAD TROUGHING BECOMES THE DOMINANT FEATURE ALOFT FRIDAY AND SATURDAY. CONSIDERING DRY SURFACE HIGH PRESSURE WILL ALSO SETTLE OVER THE REGION...EXPECT TEMPERATURES TO BE GENERALLY BELOW NORMAL AND RAIN CHANCES TO REMAIN BELOW 15 PERCENT THROUGH THE EXTENDED FORECAST PERIOD. && .AVIATION /10Z SATURDAY THROUGH WEDNESDAY/... HIGH POTENTIAL FOR DENSE FOG AT BOTH TERMINALS OVERNIGHT...BUT THE DURATION AND TIMING REMAINS IN QUESTION. KSAV HAS ALREADY DROPPED TO 1/4 MILE BUT HAS BEEN JUMPING OVER THE PAST HOUR. SUSPECT THIS IS TEMPORARY WITH OBSERVATIONS TO THE SOUTH SHOWING STEADIER DENSE FOG TRENDS. AT KCHS...CIGS SHOULD CONTINUE TO LOWER OVER THE NEXT FEW HOURS...BUT THINK THE FOG RISK MAY BE SOMEWHAT LOWER HERE GIVEN SLIGHTLY HIGHER BOUNDARY LAYER FLOW FORECAST. STILL...DENSE SEA FOG IS MOVING SLOWLY INLAND ALONG THE CHARLESTON COUNTY COAST AND MAY EVENTUALLY ENVELOP KCHS PRIOR TO DAY BREAK. WILL CALL FOR PREVAILING LIFR AT KSAV 09-13Z AND PREVAILING MVFR WITH TEMPO LIFR AT KCHS TO TREND. CONDITIONS WILL SLOWLY IMPROVE DURING THE MORNING HOURS AS A COLD FRONT APPROACHES. A LINE OF SHOWERS...POSSIBLY IN THE FORM OF A SQUALL LINE...WILL MOVE ACROSS THE TERMINALS THIS AFTERNOON...ROUGHLY 20-23Z. WILL NOT INCLUDE TSRA JUST YET...BUT WILL SHOW PREVAILING LOW-END MVFR VSBYS AND CIGS IN HEAVY RAIN. WESTERLY WINDS AND SLOWLY IMPROVING CONDITIONS WILL OCCUR THIS EVENING. EXTENDED AVIATION OUTLOOK...EXPECT COLD FRONTAL PASSAGE THIS EVENING. CONDITIONS WILL BECOME VFR TONIGHT...WITH GUSTY WEST WINDS THROUGH SUNDAY MORNING. THERE IS A CHANCE OF SHOWERS/MVFR CONDITIONS LATE MONDAY INTO EARLY TUESDAY DUE TO ANOTHER FRONTAL SYSTEM. OTHERWISE...VFR CONDITIONS SHOULD PREVAIL THROUGH WEDNESDAY. && .MARINE... TODAY...THE RISK FOR WIDESPREAD DENSE SEA FOG WILL LINGER THROUGH MUCH OF THE MORNING HOURS AND MAY PERSIST INTO THE AFTERNOON HOURS AS WARM/MOIST AIR FLOWS OVER THE COLD SHELF WATERS. A MARINE DENSE FOG ADVISORY WILL REMAIN IN FORCE UNTIL 10 AM FOR ALL FORECAST ZONES...BUT MAY NEED TO BE EXTENDED INTO THE AFTERNOON HOURS DEPENDING ON TRENDS AND PILOT BOAT REPORTS LATER THIS MORNING. OTHERWISE...SOUTH WINDS WILL INCREASE TODAY AS A COLD FRONT DRAWS CLOSER. EXPECT WINDS TO INCREASE TO 15-20 KT NEARSHORE WATERS AND 20-25 KT OFFSHORE WATERS. SEAS WILL BUILD AS A RESULT...RISING TO 4-7 FT NEARSHORE WATERS AND 6-8 FT OFFSHORE WATERS. A LINE OF STRONG TO SEVERE TSTMS WILL LIKELY APPROACH THE LOCAL MARINE AREA LATE IN THE AFTERNOON...ALTHOUGH A FEW STRONG SHOWERS/TSTMS MAY POP OVER THE COASTAL WATERS PRIOR TO ARRIVAL OF THE PRIMARY CONVECTIVE LINE. SPECIAL MARINE WARNINGS MAY BE NEEDED. TONIGHT...THE SQUALL LINE WILL PUSH ACROSS THE WATERS THIS EVENING AND BE FOLLOWED BY THE COLD FRONT. WINDS WILL QUICKLY SHIFT WEST WITH THE FRONT AND INCREASE WITH THE ONSET OF COLD AIR ADVECTION. WINDS LOOK TO PEAK 20-25 KT NEARSHORE WATERS AND 25-30 KT OFFSHORE WATERS. RIGHT NOW WINDS LOOK TO REMAIN BELOW GALE FORCE...ALTHOUGH A BRIEF STINT OF 35 KT WINDS WILL BE POSSIBLE. WILL MAINTAIN SMALL CRAFT ADVISORIES FOR ALL WATERS...EXCLUDING THE CHARLESTON HARBOR. OFFSHORE WINDS WILL HAVE A DECAYING EFFECT OF SEAS OVER THE NEARSHORE WATERS WITH SEAS SUBSIDING BY ABOUT 1-2 FT...BUT SEAS OF 6-8 FT WILL LINGER OVER THE OFFSHORE WATERS WHERE THE FETCH WILL BE CONSIDERABLY LONGER. SUNDAY THROUGH WEDNESDAY...LINGERING SMALL CRAFT ADVISORIES WILL BE ABLE TO END BY SUNDAY MORNING/EARLY AFTERNOON...AS SURFACE HIGH PRESSURE RAPIDLY BUILDS OVER THE REGION IN THE WAKE OF THE COLD FRONT. MARINE CONDITIONS WILL THEN REMAIN RATHER QUIET THROUGH THE DAYTIME HOURS ON MONDAY. A WAVE OF LOW PRESSURE IN THE GULF OF MEXICO WILL LIFT TOWARD THE SOUTHEAST STATES LATE MONDAY...LIKELY PULLING A COLD FRONT OFF THE COAST BY TUESDAY MORNING. EXPECT A SURGE IN SOUTHERLY WINDS AHEAD OF THE SYSTEM EARLY TUESDAY...WITH THE POTENTIAL FOR ONLY MARGINAL ADVISORY-LEVEL WINDS ACROSS PORTIONS OF THE WATERS. A MORE SOLID SURGE INTO SMALL CRAFT ADVISORY CONDITIONS WILL OCCUR WITHIN COLD ADVECTION AND WESTERLY FLOW BEHIND A SECONDARY COLD FRONT MOVING THROUGH THE AREA EARLY WEDNESDAY. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...DENSE FOG ADVISORY UNTIL 10 AM EST THIS MORNING FOR GAZ117>119- 139-141. SC...DENSE FOG ADVISORY UNTIL 10 AM EST THIS MORNING FOR SCZ047>052. MARINE...DENSE FOG ADVISORY UNTIL 10 AM EST THIS MORNING FOR AMZ330-350- 352-354. SMALL CRAFT ADVISORY FROM 10 AM THIS MORNING TO 5 AM EST SUNDAY FOR AMZ352-354. SMALL CRAFT ADVISORY UNTIL 8 AM EST SUNDAY FOR AMZ350. SMALL CRAFT ADVISORY UNTIL 1 PM EST SUNDAY FOR AMZ374. && $$ ST
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
358 AM EST SAT JAN 11 2014 ...SEVERE THUNDERSTORMS POSSIBLE THIS AFTERNOON AND EVENING... .SYNOPSIS... A STRONG COLD FRONT WILL SWEEP ACROSS THE REGION THIS EVENING. HIGH PRESSURE WILL BUILD SUNDAY AND QUICKLY MOVE OFF THE COAST MONDAY...BEFORE ANOTHER COLD FRONT MOVES THROUGH THE AREA BY TUESDAY MORNING. HIGH PRESSURE WILL REBUILD DURING THE MIDDLE OF NEXT WEEK...WITH YET ANOTHER COLD FRONT APPROACHING BY FRIDAY. && .NEAR TERM /THROUGH TODAY/... THROUGH SUNRISE...AREAS OF DENSE FOG HAVE DEVELOPED ACROSS A GOOD PORTION OF THE FORECAST AREA EARLY THIS MORNING...WHILE SEA FOG IMPACTS THE COASTAL AREAS. BOUNDARY LAYER WINDS ARE PROGGED TO INCREASE OVER THE NEXT FEW HOURS...WHICH MAY LEAD TO IMPROVING VISIBILITIES PRIOR TO SUNRISE. IN FACT...VISIBILITIES ARE ALREADY STARTING TO IMPROVE SLIGHTLY SOUTH OF I-16...WHICH MAY BE THE BEGINNING OF A MORE SUSTAINED TREND. WILL CONTINUE TO MONITOR VISIBILITIES OVER THE NEXT FEW HOURS AND IT IS CERTAINLY POSSIBLE THAT PORTIONS OF THE DENSE FOG ADVISORY COULD BE CANCELLED EARLY. AT THE COAST...SEA FOG WILL NOT BE AS EASILY MOVED BY THE INCREASING BOUNDARY LAYER FLOW AND WE ARE MONITORING FOR A POSSIBLE EXPANSION OF THE DENSE FOG ADVISORY INTO CHARLESTON COUNTY WHERE COASTAL WEBCAMS SHOW VERY DENSE FOG...MAINLY EAST OF HIGHWAY 17. A POTENTIALLY ACTIVE DAY IS ON TAP FOR SOUTHEAST SOUTH CAROLINA AND SOUTHEAST GEORGIA AS A COLD FRONT APPROACHES FROM THE WEST. AHEAD OF THE FRONT...INCREASING WARM AIR ADVECTION BEING DRIVEN BY A STRONG PRE-FRONTAL LOW-LEVEL JET WILL HELP PUSH TEMPERATURES INTO THE LOWER TO MID 70S FOR MOST AREAS AWAY FROM THE COAST... WHICH IS ABOUT 10-15 DEGREES ABOVE NORMAL. AS WARM AIR ADVECTION INTENSIFIES...ISOLATED TO SCATTERED SHOWERS WILL LIKELY BREAKOUT AND AFFECT PORTIONS OF THE AREA PRIOR TO THE ARRIVAL OF THE MAIN CONVECTIVE LINE. ATTM IT APPEARS THE MAIN CONVECTIVE LINE...POSSIBLY IN THE FORM OF A STRONG/SEVERE QUASI-LINEAR CONVECTIVE SYSTEM /QLCS/...WILL REACH THE FAR WESTERN ZONES BY EARLY AFTERNOON AND REACH THE COAST BY LATE AFTERNOON OR EARLY THIS EVENING. INSTABILITY PROGS AND MODIFIED POINT SOUNDINGS SUGGEST SBCAPE VALUES WILL RISE TO 800-1000 J/KG WITH LIFTED INDICES DROPPING AS LOW AS -4C. ALTHOUGH MID-LEVEL LAPSE RATES WILL BE POOR...HEALTHY 0-6KM BULK SHEAR OF 50-60 KT INDUCED BY STRONG LOW-LEVEL JETTING COUPLED WITH MODEST INSTABILITY WILL SUPPORT A RISK FOR SEVERE TSTMS WITHIN A TYPICAL MID-JANUARY HIGH SHEAR/LOW CAPE ENVIRONMENT. THE PRIMARY HAZARD RIGHT NOW LOOK TO BE DAMAGING WINDS WITH A RISK FOR ISOLATED TORNADOES WHERE DISCRETE CELLS OR EMBEDDED MESO-VORTICES WITHIN BOWING CONVECTIVE SEGMENTS CAN DEVELOP. RAP 0-1KM HELICITY VALUES INCREASE TO NEAR 300 M2/S2 AND THE HIGH SHEAR/LOW CAPE SHERBS3 TORNADO PARAMETER RISES ABOVE THE BENCH MARK OF 1 UNIT FOR MUCH OF THE AREA...ALL SUGGESTING THERE IS A REASONABLE RISK FOR TORNADOES. FOR TODAY...WILL HIGHLIGHT POPS NEAR 100 PERCENT FOR ALL AREAS WITH THE HIGHEST GRIDDED POPS PLACED WITH THE EXPECTED TIMING/PLACEMENT OF THE EXPECTED CONVECTIVE LINE. HIGHS WILL BE IN THE LOWER TO MID 70S UNDER MAINLY CLOUDY SKIES. WILL INCLUDE DAMAGING WIND AND TORNADO ATTRIBUTES IN ALL GRIDDED AND TEXT PRODUCTS AND HIGHLIGHT A POTENTIAL FOR SEVERE TSTMS IN THE HAZARDOUS WEATHER OUTLOOK. THE WINDOW OF GREATEST SEVERE THREAT LOOKS TO BE 1 PM THROUGH 7 PM. && .SHORT TERM /TONIGHT THROUGH TUESDAY/... TONIGHT...CONDITIONS WILL RAPIDLY IMPROVE THIS EVENING AS THE PRIMARY CONVECTIVE LINE PUSHES OFFSHORE AND THE COLD FRONT MOVES THROUGH. EXPECT CLEARING TO OCCUR DURING THE EVENING HOURS WITH MAINLY CLEAR SKIES DEVELOPING BY MIDNIGHT...IF NOT SOONER. LOWS WILL RANGE FROM THE LOWER 40S WELL INLAND TO THE UPPER 40S AT THE BEACHES. SUNDAY...DRY HIGH PRESSURE WILL BUILD IN THE WAKE OF THE DEPARTING COLD FRONT...YET PROGRESSIVE FLOW ALOFT WILL PULL THE CENTER OF THE HIGH QUICKLY TOWARD THE NEARBY ATLANTIC WATERS. COLD ADVECTION WILL BE WEAK BEHIND THE FRONT...AND WITH WIND DIRECTIONS REMAINING GENERALLY WEST/SOUTHWEST...EXPECT ONLY A SLIGHT COOLING TREND TO OCCUR. HIGH TEMPERATURES IN THE MID TO UPPER 60S WILL BE COOLER THAN THE PREVIOUS DAY...YET STILL BE WELL ABOVE SEASONAL NORMALS. AN AMPLIFYING LONG WAVE TROUGH ACROSS THE CENTRAL PLAINS AFTER MIDNIGHT WILL SUPPORT BRIEF DOWNSTREAM HEIGHT RISES...AND WHEN COMBINED WITH WARM ADVECTION WITHIN BACKING LOW LEVEL FLOW...LOW TEMPERATURES IN THE UPPER 30S INLAND TO LOW 40S NEAR THE COAST WILL ALSO BE SEVERAL DEGREES WARMER THAN AVERAGE. MONDAY...SOUTHERN STREAM SHORTWAVE ENERGY TRACKING ACROSS THE GULF OF MEXICO WILL SPIN UP A SURFACE WAVE ALONG THE WESTERN PERIPHERY OF THE RETREATING ATLANTIC HIGH PRESSURE. THERE REMAINS NOTABLE DISAGREEMENT BETWEEN MODEL SOLUTIONS REGARDING THE STRENGTH AND TRACK OF THIS LOW PRESSURE WAVE AND TRAILING FRONT AS THEY PROGRESS TOWARD THE FORECAST AREA THROUGH THE DAY. IN GENERAL...A SOLID TAP INTO GULF MOISTURE WILL SUPPORT A SWATH OF PRECIPITATION ASSOCIATED WITH THE SYSTEM...AND EXPECT RAIN CHANCES TO INCREASE FROM SOUTHWEST TO NORTHEAST DURING THE LATE AFTERNOON TO EVENING TIME FRAME. WARM ADVECTION AND PRE-FRONTAL COMPRESSION WILL SUPPORT TEMPERATURES PEAKING IN THE MID TO UPPER 60S...EVEN AS CLOUD COVER GRADUALLY INCREASES. THE BEST RAIN POTENTIAL ACTUALLY APPEARS TO OCCUR OVERNIGHT INTO EARLY TUESDAY MORNING..AS THE SURFACE LOW LIFTS NORTH/NORTHEAST AND PULLS THE FRONT INTO THE REGION. LOW TEMPERATURES WILL BE QUITE MILD AS A RESULT...ONLY FALLING INTO THE UPPER 40S TO AROUND 50 DEGREES. TUESDAY...THE SYNOPTIC PATTERN REMAINS A BIT UNSETTLED EVEN AFTER THE FRONT MOVES OFFSHORE...WITH ANOTHER LARGE AREA OF UPPER LEVEL ENERGY SWEEPING SOUTHEAST FROM THE GREAT LAKES REGION. RAIN CHANCES WILL DECREASE DURING THE MORNING HOURS BEHIND THE DEPARTING COLD FRONT. HOWEVER DRY SURFACE HIGH PRESSURE IN ITS WAKE WILL BECOME SUPPRESSED TO THE SOUTH...AS YET ANOTHER FRONT DRIVEN BY THE AMPLIFYING UPPER SHORTWAVE DESCENDS FROM THE OHIO VALLEY LATE IN THE DAY. ONCE AGAIN...DOWNSLOPE FLOW AND THE LACK OF SOLID COLD ADVECTION WILL SUPPORT ABOVE NORMAL HIGH TEMPERATURES IN THE MID 60S. && .LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/... THE DEEPENING UPPER TROUGH WILL SHIFT OVER THE EAST COAST STATES ON WEDNESDAY...WITH A DRY COLD FRONT MOVING ACROSS THE REGION EARLY IN THE DAY. THERE APPEARS TO BE MORE NOTABLE COLD ADVECTION BEHIND THIS FRONT...AND EXPECT HIGH TEMPERATURES TO BE SUPPRESSED IN THE MID 50S UNDER MOSTLY CLEAR SKIES ON WEDNESDAY. LOW TEMPERATURES WEDNESDAY NIGHT WILL BE THE COLDEST SEEN IN DAYS...AS LIGHT WINDS AND LITTLE TO NO CLOUD COVER SET UP IDEAL RADIATIONAL COOLING CONDITIONS. A NEARLY ZONAL UPPER PATTERN ON THURSDAY WILL BE RATHER TRANSIENT...AS BROAD TROUGHING BECOMES THE DOMINANT FEATURE ALOFT FRIDAY AND SATURDAY. CONSIDERING DRY SURFACE HIGH PRESSURE WILL ALSO SETTLE OVER THE REGION...EXPECT TEMPERATURES TO BE GENERALLY BELOW NORMAL AND RAIN CHANCES TO REMAIN BELOW 15 PERCENT THROUGH THE EXTENDED FORECAST PERIOD. && .AVIATION /07Z SATURDAY THROUGH WEDNESDAY/... HIGH POTENTIAL FOR DENSE FOG AT BOTH TERMINALS OVERNIGHT...BUT THE DURATION AND TIMING REMAINS IN QUESTION. KSAV HAS ALREADY DROPPED TO 1/4 MILE BUT HAS BEEN JUMPING OVER THE PAST HOUR. SUSPECT THIS IS TEMPORARY WITH OBSERVATIONS TO THE SOUTH SHOWING STEADIER DENSE FOG TRENDS. AT KCHS...CIGS SHOULD CONTINUE TO LOWER OVER THE NEXT FEW HOURS...BUT THINK THE FOG RISK MAY BE SOMEWHAT LOWER HERE GIVEN SLIGHTLY HIGHER BOUNDARY LAYER FLOW FORECAST. STILL...DENSE SEA FOG IS MOVING SLOWLY INLAND ALONG THE CHARLESTON COUNTY COAST AND MAY EVENTUALLY ENVELOP KCHS PRIOR TO DAY BREAK. WILL CALL FOR PREVAILING LIFR AT KSAV 09-13Z AND PREVAILING MVFR WITH TEMPO LIFR AT KCHS TO TREND. CONDITIONS WILL SLOWLY IMPROVE DURING THE MORNING HOURS AS A COLD FRONT APPROACHES. A LINE OF SHOWERS...POSSIBLY IN THE FORM OF A SQUALL LINE...WILL MOVE ACROSS THE TERMINALS THIS AFTERNOON...ROUGHLY 20-23Z. WILL NOT INCLUDE TSRA JUST YET...BUT WILL SHOW PREVAILING LOW-END MVFR VSBYS AND CIGS IN HEAVY RAIN. WESTERLY WINDS AND SLOWLY IMPROVING CONDITIONS WILL OCCUR THIS EVENING. EXTENDED AVIATION OUTLOOK...EXPECT COLD FRONTAL PASSAGE THIS EVENING. CONDITIONS WILL BECOME VFR TONIGHT...WITH GUSTY WEST WINDS THROUGH SUNDAY MORNING. THERE IS A CHANCE OF SHOWERS/MVFR CONDITIONS LATE MONDAY INTO EARLY TUESDAY DUE TO ANOTHER FRONTAL SYSTEM. OTHERWISE...VFR CONDITIONS SHOULD PREVAIL THROUGH WEDNESDAY. && .MARINE... TODAY...THE RISK FOR DENSE SEA FOG WILL LINGER THROUGH MUCH OF THE MORNING HOURS AND MAY PERSIST INTO THE AFTERNOON HOURS AS WARM/MOIST AIR FLOWS OVER THE COLD SHELF WATERS. A MARINE DENSE FOG ADVISORY WILL REMAIN IN FORCE UNTIL 10 AM FOR ALL FORECAST ZONES...BUT MAY NEED TO BE EXTENDED INTO THE AFTERNOON HOURS DEPENDING ON TRENDS AND PILOT BOAT REPORTS LATER THIS MORNING. OTHERWISE...SOUTH WINDS WILL INCREASE TODAY AS A COLD FRONT DRAWS CLOSER. EXPECT WINDS TO INCREASE TO 15-20 KT NEARSHORE WATERS AND 20-25 KT OFFSHORE WATERS. SEAS WILL BUILD AS A RESULT...RISING TO 4-7 FT NEARSHORE WATERS AND 6-8 FT OFFSHORE WATERS. A LINE OF STRONG TO SEVERE TSTMS WILL LIKELY APPROACH THE LOCAL MARINE AREA LATE IN THE AFTERNOON...ALTHOUGH A FEW STRONG SHOWERS/TSTMS MAY POP OVER THE COASTAL WATERS PRIOR TO ARRIVAL OF THE PRIMARY CONVECTIVE LINE. SPECIAL MARINE WARNINGS MAY BE NEEDED. TONIGHT...THE SQUALL LINE WILL PUSH ACROSS THE WATERS THIS EVENING AND BE FOLLOWED BY THE COLD FRONT. WINDS WILL QUICKLY SHIFT WEST WITH THE FRONT AND INCREASE WITH THE ONSET OF COLD AIR ADVECTION. WINDS LOOK TO PEAK 20-25 KT NEARSHORE WATERS AND 25-30 KT OFFSHORE WATERS. RIGHT NOW WINDS LOOK TO REMAIN BELOW GALE FORCE...ALTHOUGH A BRIEF STINT OF 35 KT WINDS WILL BE POSSIBLE. WILL MAINTAIN SMALL CRAFT ADVISORIES FOR ALL WATERS...EXCLUDING THE CHARLESTON HARBOR. OFFSHORE WINDS WILL HAVE A DECAYING EFFECT OF SEAS OVER THE NEARSHORE WATERS WITH SEAS SUBSIDING BY ABOUT 1-2 FT...BUT SEAS OF 6-8 FT WILL LINGER OVER THE OFFSHORE WATERS WHERE THE FETCH WILL BE CONSIDERABLY LONGER. SUNDAY THROUGH WEDNESDAY...LINGERING SMALL CRAFT ADVISORIES WILL BE ABLE TO END BY SUNDAY MORNING/EARLY AFTERNOON...AS SURFACE HIGH PRESSURE RAPIDLY BUILDS OVER THE REGION IN THE WAKE OF THE COLD FRONT. MARINE CONDITIONS WILL THEN REMAIN RATHER QUIET THROUGH THE DAYTIME HOURS ON MONDAY. A WAVE OF LOW PRESSURE IN THE GULF OF MEXICO WILL LIFT TOWARD THE SOUTHEAST STATES LATE MONDAY...LIKELY PULLING A COLD FRONT OFF THE COAST BY TUESDAY MORNING. EXPECT A SURGE IN SOUTHERLY WINDS AHEAD OF THE SYSTEM EARLY TUESDAY...WITH THE POTENTIAL FOR ONLY MARGINAL ADVISORY-LEVEL WINDS ACROSS PORTIONS OF THE WATERS. A MORE SOLID SURGE INTO SMALL CRAFT ADVISORY CONDITIONS WILL OCCUR WITHIN COLD ADVECTION AND WESTERLY FLOW BEHIND A SECONDARY COLD FRONT MOVING THROUGH THE AREA EARLY WEDNESDAY. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...DENSE FOG ADVISORY UNTIL 10 AM EST THIS MORNING FOR GAZ087-088- 099>101-114>119-137>141. SC...DENSE FOG ADVISORY UNTIL 10 AM EST THIS MORNING FOR SCZ040-042- 043-047>049-051. MARINE...DENSE FOG ADVISORY UNTIL 10 AM EST THIS MORNING FOR AMZ330-350- 352-354. SMALL CRAFT ADVISORY FROM 10 AM THIS MORNING TO 5 AM EST SUNDAY FOR AMZ352-354. SMALL CRAFT ADVISORY UNTIL 8 AM EST SUNDAY FOR AMZ350. SMALL CRAFT ADVISORY UNTIL 1 PM EST SUNDAY FOR AMZ374. && $$ ST/WMS
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
242 AM EST SAT JAN 11 2014 .SYNOPSIS... A COLD FRONT WILL MOVE THROUGH THE FORECAST AREA THIS AFTERNOON. HIGH PRESSURE BEHIND THE FRONT WILL BE OVER OUR REGION SUNDAY. THE HIGH WILL MOVE OFF THE COAST SUNDAY NIGHT. ANOTHER COLD FRONT WILL MOVE INTO THE AREA MONDAY NIGHT. && .NEAR TERM /THROUGH TODAY/... HIGH LOW-LEVEL MOISTURE AND CONVERGENCE NEAR THE WEDGE/WARM FRONT HAS RESULTED IN WIDESPREAD FOG THIS MORNING. THERE WERE AREAS OF DENSE FOG AND WE HAVE ISSUED A DENSE FOG ADVISORY. THE HRRR MAINTAINS FOG OVER MUCH OF THE AREA THROUGH 1000 AM. THE FOG WILL LIKELY DIMINISH AS DEEPER MOISTURE AND INCREASED MIXING ASSOCIATED WITH THE FRONT NEARS THE AREA LATER THIS MORNING. HIGH MOISTURE ASSOCIATED WITH THE STRONG H85 JET AND LIFT WITH THE RIGHT ENTRANCE REGION OF THE H25 JET PLUS CONVERGENCE ALONG THE COLD FRONT SUPPORT CATEGORICAL POPS TODAY. THE NAM AND GFS ARE CLOSE WITH GENERAL RAINFALL TOTALS AROUND 0.6 OF AN INCH...BUT WITH PRECIPITABLE WATER NEAR 1.6 OF AN INCH HEAVIER AMOUNTS WILL LIKELY OCCUR IN SOME LOCATIONS. THE NAM DISPLAYS SURFACE-BASED LI/S LOWERING TO -1 TO -2 THIS AFTERNOON. THE INSTABILITY IS QUESTIONABLE BECAUSE IT SHOULD BE LIMITED BY FOG EARLY AND THEN WIDESPREAD SHOWERS. HOWEVER...IF SURFACE-BASED INSTABILITY DOES DEVELOP THEN SEVERE THUNDERSTORMS MAY OCCUR BECAUSE OF STRONG SHEAR. THE NAM AND GFS HAVE H85 WINDS NEAR 60 KNOTS. THE MAIN THREAT IS DAMAGING STRAIGHT-LINE WINDS BUT FORECAST HODOGRAPHS ALSO SUPPORT POSSIBLE TORNADOES. THE 03Z HRRR SHOWS THE MAIN CONVECTIVE LINE ABOUT TO ENTER THE WEST PART OF THE FORECAST AREA AT 100 PM. THIS MODEL ALSO SHOWS DEVELOPMENT AHEAD OF THIS LINE FARTHER SOUTH IN COASTAL GEORGIA WHICH MAY TEND TO LIMIT THE TRANSPORT OF MOISTURE AND INSTABILITY FARTHER NORTH AND INTO THE FORECAST AREA. THE 00Z SPC WRF DISPLAYS THE MAIN CONVECTIVE LINE IN THE FORECAST AREA DURING THE 300 PM TO 700 PM TIME FRAME...BUT THIS CONVECTION APPEARS TO WEAKEN AS UPSTREAM DEVELOPMENT NEAR THE COAST BECOMES MORE DOMINATE. WE USED THE COOLER TEMPERATURE GUIDANCE TODAY BECAUSE OF CLOUDINESS AND SHOWERS. && .SHORT TERM /TONIGHT THROUGH MONDAY/... DRYING WILL OCCUR BEHIND THE FRONT TONIGHT. THE SHOWER CHANCE WILL DECREASE RAPIDLY FROM WEST TO EAST DURING THE EVENING. HIGH PRESSURE WILL BE OVER THE FORECAST AREA SUNDAY. THE HIGH WILL MOVE OFF THE COAST SUNDAY NIGHT. THE TEMPERATURE GUIDANCE WAS CONSISTENT. TEMPERATURES WILL BE ABOVE NORMAL. && .LONG TERM /MONDAY NIGHT THROUGH FRIDAY/... THE GFS AND ECMWF DISPLAY MOISTURE ASSOCIATED WITH A COLD FRONT MONDAY NIGHT INTO TUESDAY. THE ECMWF CONTINUES TO INDICATE MORE MOISTURE COMPARED TO THE GFS. CONTINUED CHANCE POPS BECAUSE OF THE MODEL INCONSISTENCY. EXPECT A REINFORCING COLD FRONT WITH LIMITED MOISTURE WEDNESDAY. THE MODELS SHOW DRY RIDGING DOMINATING THURSDAY WITH YET ANOTHER COLD FRONT WILL LITTLE MOISTURE FRIDAY. ABOVE NORMAL TEMPERATURES SHOULD OCCUR AHEAD OF THE FRONT TUESDAY...WITH COOLING TO NEAR OR SLIGHTLY BELOW NORMAL BY THURSDAY. && .AVIATION /07Z SATURDAY THROUGH WEDNESDAY/... RESTRICTIONS DOMINATING THROUGH 12/00Z THEN CONDITIONS IMPROVING. SHOWERS HAVE DIMINISHED ACROSS THE TAF SITES...HOWEVER WITH CALM WINDS CIGS AND VSBYS HAVE LOWERED INTO THE LIFR RANGE. EXPECT CONDITIONS TO REMAIN LIFR THROUGH 13Z WHEN THE PRESSURE GRADIENT AHEAD OF THE COLD FRONT WILL INCREASE WINDS AND IMPROVE CIGS AND VSBYS TO IFR RANGE. COLD FRONT WILL MOVE INTO THE TAF SITES DURING THE MORNING ALONG WITH SHOWERS AND GUSTY WINDS. CONFIDENCE IN THUNDERSTORMS CONTINUES TO INCREASE...HOWEVER TIMING CONFIDENCE IS TOO LOW TO INCLUDE IN TAFS ATTM. BEST POTENTIAL FOR THUNDERSTORMS WILL BE 16Z THROUGH 22Z. CONDITIONS WILL RAPIDLY IMPROVE AS THE FRONT MOVES EAST OF THE TAF SITES WITH VFR CONDITIONS RETURNING TO ALL SITES BY 12/02Z. WINDS WILL BE LIGHT AND VARIABLE WINDS THROUGH 13Z THEN INCREASE STEADILY TO SOUTHERLY AT 15 KNOTS WITH GUSTS TO 25 KNOTS...FINALLY VEERING TO WESTERLY AT 10 KNOTS GUSTING TO 18 KNOTS BEHIND THE FRONT. EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE MONDAY NIGHT THROUGH TUESDAY MORNING IN SHOWERS ASSOCIATED WITH THE NEXT COLD FRONT. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...DENSE FOG ADVISORY UNTIL 10 AM EST THIS MORNING FOR SCZ015-016- 018-020>022-025>031-035>038-041. GA...DENSE FOG ADVISORY UNTIL 10 AM EST THIS MORNING FOR GAZ040- 063>065-077. && $$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
111 AM EST SAT JAN 11 2014 .SYNOPSIS... HIGH PRESSURE CENTERED OFF THE NORTHEAST COAST WILL CIRCULATE MOIST AIR FROM THE ATLANTIC INTO THE FORECAST AREA AHEAD OF A COLD FRONT APPROACHING FROM THE WEST. THE FRONT WILL MOVE THROUGH THE AREA SATURDAY. HIGH PRESSURE WILL BUILD IN BEHIND THE FRONT SUNDAY AND MONDAY. && .NEAR TERM /UNTIL 7 AM THIS MORNING/... MOISTURE HAS BECOME MORE SHALLOW BEHIND A MID- LEVEL SHORTWAVE THROUGH. EXPECT LIMITED SHOWER COVERAGE OVERNIGHT. THE HIGH LOW- LEVEL MOISTURE AND WEDGE/WARM FRONT IN THE AREA IS SUPPORTING FOG. OBSERVATION TRENDS AND THE HRRR SUPPORT DENSE FOG. WE HAVE ISSUED A DENSE FOG ADVISORY. && .SHORT TERM /7 AM THIS MORNING THROUGH MONDAY NIGHT/... ON SATURDAY A COLD FRONT APPROACHES FROM THE WEST AND MOVES ACROSS THE CWA SATURDAY AFTERNOON. RAIN CHANCES WILL INCREASE TO NEAR 100 PERCENT AHEAD OF THE FRONT FROM LATE SATURDAY MORNING THROUGH THE AFTERNOON. SEVERE WEATHER IS ALSO A CONCERN WITH THE WARM MOIST AIR MASS RESULTING IN LI/S UP TO -3 AND A STRONG LOW- LEVEL JET OF NEARLY 60 KTS. SPC HAS THE CWA IN A SLIGHT RISK FOR SEVERE. THE MAIN THREAT FOR SEVERE IS FROM DAMAGING WINDS IN THE CONVECTIVE LINE ASSOCIATED WITH THE FRONT. HOWEVER STRONG SHEAR MAY ALSO INCLUDE THE RISK FOR SOME ROTATION EMBEDDED IN THE LINE. DRYING WILL OCCUR BEHIND THE FRONT SATURDAY NIGHT. POPS WILL DECREASE RAPIDLY FROM WEST TO EAST SATURDAY EVENING. HIGH PRESSURE AND DRY WEATHER WITH TEMPERATURES ABOVE THE SEASONAL AVERAGE WILL BE ON TAP FOR SUNDAY AND MONDAY. && .LONG TERM /TUESDAY THROUGH FRIDAY/... THE MODELS DISPLAY MOISTURE ASSOCIATED WITH A COLD FRONT INTO EARLY TUESDAY MORNING. THE ECMWF SHOWS A MUCH STRONGER SYSTEM BRINGING LIKELY POPS. GFS WITH MUCH WEAKER SYSTEM PULLING TO THE NORTH TUESDAY. WILL CONTINUE CHANCE POPS. EXPECT A REINFORCING COLD FRONT WITH LIMITED MOISTURE WEDNESDAY. TIGHT PRESSURE GRADIENT EXPECTED WEDNESDAY RESULTING IN BREEZY CONDITIONS. ABOVE NORMAL TEMPERATURES SHOULD OCCUR TUESDAY...WITH NEAR OR SLIGHTLY BELOW NORMAL READINGS BEHIND THE FRONT BY THURSDAY. && .AVIATION /06Z SATURDAY THROUGH WEDNESDAY/... RESTRICTIONS DOMINATING THROUGH 12/00Z THEN CONDITIONS IMPROVING. SHOWERS HAVE DIMINISHED ACROSS THE TAF SITES...HOWEVER WITH CALM WINDS CIGS AND VSBYS HAVE LOWERED INTO THE LIFR RANGE. EXPECT CONDITIONS TO REMAIN LIFR THROUGH 13Z WHEN THE PRESSURE GRADIENT AHEAD OF THE COLD FRONT WILL INCREASE WINDS AND IMPROVE CIGS AND VSBYS TO IFR RANGE. COLD FRONT WILL MOVE INTO THE TAF SITES DURING THE MORNING ALONG WITH SHOWERS AND GUSTY WINDS. CONFIDENCE IN THUNDERSTORMS CONTINUES TO INCREASE...HOWEVER TIMING CONFIDENCE IS TOO LOW TO INCLUDE IN TAFS ATTM. BEST POTENTIAL FOR THUNDERSTORMS WILL BE 16Z THROUGH 22Z. CONDITIONS WILL RAPIDLY IMPROVE AS THE FRONT MOVES EAST OF THE TAF SITES WITH VFR CONDITIONS RETURNING TO ALL SITES BY 12/02Z. WINDS WILL BE LIGHT AND VARIABLE WINDS THROUGH 13Z THEN INCREASE STEADILY TO SOUTHERLY AT 15 KNOTS WITH GUSTS TO 25 KNOTS...FINALLY VEERING TO WESTERLY AT 10 KNOTS GUSTING TO 18 KNOTS BEHIND THE FRONT. EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE MONDAY NIGHT THROUGH TUESDAY MORNING IN SHOWERS ASSOCIATED WITH THE NEXT COLD FRONT. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...DENSE FOG ADVISORY UNTIL 10 AM EST THIS MORNING FOR SCZ015-016- 018-020>022-025>031-035>038-041. GA...DENSE FOG ADVISORY UNTIL 10 AM EST THIS MORNING FOR GAZ040- 063>065-077. && $$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
1220 AM EST SAT JAN 11 2014 .SYNOPSIS... HIGH PRESSURE CENTERED OFF THE NORTHEAST COAST WILL CIRCULATE MOIST AIR FROM THE ATLANTIC INTO THE FORECAST AREA AHEAD OF A COLD FRONT APPROACHING FROM THE WEST. THE FRONT WILL MOVE THROUGH THE AREA SATURDAY. HIGH PRESSURE WILL BUILD IN BEHIND THE FRONT SUNDAY AND MONDAY. && .NEAR TERM /UNTIL 7 AM THIS MORNING/... MOISTURE HAS BECOME MORE SHALLOW BEHIND A MID-LEVEL SHORTWAVE THROUGH. EXPECT LIMITED SHOWER COVERAGE OVERNIGHT. THE HIGH LOW- LEVEL MOISTURE AND WEDGE/WARM FRONT IN THE AREA IS SUPPORTING FOG. OBSERVATION TRENDS AND THE HRRR SUPPORT DENSE FOG. WE HAVE ISSUED A DENSE FOG ADVISORY. && .SHORT TERM /7 AM THIS MORNING THROUGH MONDAY NIGHT/... ON SATURDAY A COLD FRONT APPROACHES FROM THE WEST AND MOVES ACROSS THE CWA SATURDAY AFTERNOON. RAIN CHANCES WILL INCREASE TO NEAR 100 PERCENT AHEAD OF THE FRONT FROM LATE SATURDAY MORNING THROUGH THE AFTERNOON. SEVERE WEATHER IS ALSO A CONCERN WITH THE WARM MOIST AIR MASS RESULTING IN LI/S UP TO -3 AND A STRONG LOW- LEVEL JET OF NEARLY 60 KTS. SPC HAS THE CWA IN A SLIGHT RISK FOR SEVERE. THE MAIN THREAT FOR SEVERE IS FROM DAMAGING WINDS IN THE CONVECTIVE LINE ASSOCIATED WITH THE FRONT. HOWEVER STRONG SHEAR MAY ALSO INCLUDE THE RISK FOR SOME ROTATION EMBEDDED IN THE LINE. DRYING WILL OCCUR BEHIND THE FRONT SATURDAY NIGHT. POPS WILL DECREASE RAPIDLY FROM WEST TO EAST SATURDAY EVENING. HIGH PRESSURE AND DRY WEATHER WITH TEMPERATURES ABOVE THE SEASONAL AVERAGE WILL BE ON TAP FOR SUNDAY AND MONDAY. && .LONG TERM /TUESDAY THROUGH FRIDAY/... THE MODELS DISPLAY MOISTURE ASSOCIATED WITH A COLD FRONT INTO EARLY TUESDAY MORNING. THE ECMWF SHOWS A MUCH STRONGER SYSTEM BRINGING LIKELY POPS. GFS WITH MUCH WEAKER SYSTEM PULLING TO THE NORTH TUESDAY. WILL CONTINUE CHANCE POPS. EXPECT A REINFORCING COLD FRONT WITH LIMITED MOISTURE WEDNESDAY. TIGHT PRESSURE GRADIENT EXPECTED WEDNESDAY RESULTING IN BREEZY CONDITIONS. ABOVE NORMAL TEMPERATURES SHOULD OCCUR TUESDAY...WITH NEAR OR SLIGHTLY BELOW NORMAL READINGS BEHIND THE FRONT BY THURSDAY. && .AVIATION /05Z SATURDAY THROUGH WEDNESDAY/... HIGH CONFIDENCE IN RESTRICTIONS DOMINATING THE PERIOD. REGIONAL RADAR COMPOSITE SHOWS MOST OF THE MODERATE TO HEAVY RAIN HAS NOW SHIFTED NORTHEAST OF THE TAF SITES WITH SCATTERED SHOWERS AND DRIZZLE CONTINUING ACROSS THE AREA. EXPECT IFR/LIFR CONDITIONS TO CONTINUE OVERNIGHT AND INTO SATURDAY. CHANCES OF SHOWERS AND POSSIBLY THUNDERSTORMS WILL INCREASE SATURDAY AS A COLD FRONT APPROACHES. DID NOT INCLUDE MENTION OF THUNDER AT THIS TIME DUE TO LOW CONFIDENCE IN TIMING. WINDS WILL ROTATE FROM NORTHEASTERLY TO SOUTHERLY OVERNIGHT AND REMAIN LIGHT. WINDS WILL INCREASE ON SATURDAY AHEAD OF THE FRONTAL BOUNDARY AND BECOME MORE SOUTHWESTERLY BY LATE AFTERNOON AS THE COLD FRONT CROSSES THE AREA. HIGHER WIND GUSTS MAY MIX DOWN TO THE SURFACE PARTICULARLY IN THE CONVECTIVE LINE ASSOCIATED WITH THE FRONT. SHOWERS SHOULD SHIFT EAST OF THE AREA TOWARD THE END OF THE TAF PERIOD WITH RESTRICTIONS IMPROVING. EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE MONDAY NIGHT THROUGH TUESDAY MORNING IN SHOWERS ASSOCIATED WITH THE NEXT COLD FRONT. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...DENSE FOG ADVISORY UNTIL 10 AM EST THIS MORNING FOR SCZ015-016- 018-020>022-025>031-035>038-041. GA...DENSE FOG ADVISORY UNTIL 10 AM EST THIS MORNING FOR GAZ040- 063>065-077. && $$
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1141 PM CST FRI JAN 10 2014 .UPDATE... ISSUED AT 749 PM CST FRI JAN 10 2014 QUITE A FEW SITES NOW 1/2 TO 1/4 MILE ON VISIBILITIES AND SHOULD CONTINUE TO SEE VERY LOW VISIBILITIES BECOME WIDESPREAD WITH ABUNDANT MOISTURE AND DIMINISHING WINDS AHEAD OF PASSING SURFACE LOW. AS RESULT... HAVE ISSUED A DENSE FOG ADVISORY FOR THE ENTIRE CWA FOR THE REST OF TONIGHT. LATE TONIGHT... SAY AROUND 09Z OR SO WE MAY START TO SEE SOME IMPROVEMENT ON VISIBILITIES AS A FRONTAL BOUNDARY MOVES THROUGH THE REGION. THE POOR VISIBILITIES IN DENSE FOG COUPLED WITH ICY ROADWAYS ESPECIALLY NEAR/NORTH OF I-80 MAKING IT ONE OF THOSE NIGHTS BEST SUITED FOR NOT TRAVELING UNLESS NECESSARY. UPDATE ISSUED AT 444 PM CST FRI JAN 10 2014 EXPANDED ADVISORY TO INCLUDE JACKSON COUNTY IN IOWA AND JO DAVIESS AND STEPHENSON COUNTIES IN FAR NORTHERN ILLINOIS. REPORTS OF SEVERAL ROADS COMPLETELY COVERED IN JACKSON COUNTY... IA38...IA136 IA64. PAVEMENT TEMPS HOVERING AROUND FREEZING IN THESE AREAS ALLOWING FOR THE ICY CONDITIONS TO DEVELOP. COULD ACTUALLY SEE SOME IMPROVEMENT FOR A TIME THIS EVENING AS TEMPS CONTINUE TO SLOWLY CLIMB AHEAD OF AN APPROACHING SURFACE LOW. HOWEVER....ONCE THIS PASSES AND WINDS SHIFT TO WEST WILL SEE TEMPS DROP LATE THIS EVE AND OVERNIGHT AND MAY SEE MORE ICING WHETHER THROUGH REFREEZE OR POSSIBLY SOME LIGHT FREEZING DRIZZLE/FREEZING RAIN. UPDATE ISSUED AT 336 PM CST FRI JAN 10 2014 CALLS ARE NOW COMING IN REPORTING SLICK ROADS. THUS WILL HOIST A FREEZING RAIN ADVISORY FOR LATE AFTERNOON AND EVENING. TEMPORAL AND AREAL COVERAGE OF THE ADVISORY MAY NEED TO CHANGED THIS EVENING. && .SYNOPSIS... ISSUED AT 248 PM CST FRI JAN 10 2014 12Z UA ANALYSIS HAS A LLJ RUNNING FROM TEXAS INTO WESTERN MISSOURI. MOISTURE ASSOCIATED WITH THIS JET WAS IMPINGING UPON AN 850 MB WARM FRONT RUNNING FROM KANSAS INTO SOUTHERN ILLINOIS. RADAR TRENDS THROUGH MID AFTERNOON HAD A LARGE AREA OF RAIN FROM MISSOURI INTO ILLINOIS WITH LIGHTER RAIN/DRIZZLE MIXED WITH SOME FREEZING RAIN/DRIZZLE ACROSS IOWA. 18Z SFC ANALYSIS HAS A WEAK LOW NEAR KMHK WITH A WARM FRONT EAST ALONG THE MISSOURI RIVER. THE COLD FRONT RAN FROM THE LOW INTO SOUTHWEST OKLAHOMA. DEW POINTS WERE IN THE 20S AND 30S ACROSS THE UPPER MIDWEST AND GREAT LAKES WITH 40S AND HIGHER FROM THE OHIO VALLEY AND SOUTHERN PLAINS. && .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 248 PM CST FRI JAN 10 2014 BASED ON TRENDS FROM PRESSURE FALLS AND THE RAP MODEL...THE LOW SHOULD PASS OVER THE FAR NORTHWEST AREA BETWEEN KALO AND KCID THIS EVENING. WINDS WILL DECREASE AS THE LOW APPROACHES AND THE FOG IS EXPECTED TO BECOME MORE WIDESPREAD. RIGHT NOW NO ADVISORY FOR DENSE FOG IS PLANNED. HOWEVER...I WOULD NOT BE SURPRISED IF ONE IS NEEDED AT SOME POINT DURING THE EVENING. TEMPERATURES HAVE NOT BUDGED MUCH IN THE HIGHWAY 20 CORRIDOR FROM KDBQ ON WEST. THUS THIS AREA IS RIGHT ON THE CUSP OF SEEING FREEZING RAIN LATE THIS AFTERNOON AND EVENING AS LIFT CONTINUES TO INCREASE. HOWEVER...THE TRACK OF THE LOW SHOULD ALLOW TEMPERATURES TO RISE ABOUT ANOTHER DEGREE. FREEZING RAIN IS EXPECTED TO BE LOCALLY SPOTTY OVER THE FOUR NORTHWEST COUNTIES AND POSSIBLY WESTERN DUBUQUE COUNTY THROUGH MID EVENING. ONCE THE LOW PASSES...COLD AIR WILL SLOWLY BEGIN TO MOVE INTO THE AREA ALLOWING THE RAIN TO MIX WITH AND CHANGE TO SNOW FROM WEST TO EAST OVERNIGHT. DURING THE CHANGE OVER...A BRIEF PERIOD OF FREEZING RAIN WILL BE POSSIBLE. SNOW AMOUNTS WILL RANGE FROM A TRACE TO UNDER AN INCH. ON SATURDAY...LINGERING LIGHT SNOW WILL BE SEE OVER ROUGHLY THE NORTHEAST/EAST HALF OF THE AREA DURING THE MORNING. OTHERWISE DRY CONDITIONS ARE EXPECTED DURING THE DAY. SNOW AMOUNTS SATURDAY MORNING WILL BE A DUSTING AT BEST. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 248 PM CST FRI JAN 10 2014 NEARLY ZONAL UPPER AIR FLOW WILL BE OVER THE AREA THE REST OF THE WEEKEND THEN THE PATTERN CHANGES TO A RIDGE DOMINATED WESTERN U.S. AND A MEAN TROF SETTING UP OVER THE EAST. MILD CONDITIONS ARE ANTICIPATED FOR THE REGION SUNDAY AS UPPER RIDGING BUILDS OVER THE AREA SATURDAY NIGHT INTO SUNDAY. IN THE LOW LEVELS A SURFACE RIDGE WILL MOVE THROUGH THE REGION SATURDAY EVENING FOLLOWED BY STRONG LOW LEVEL WAA AHEAD OF A TROF DIGGING INTO THE SOUTHWEST U.S. AND A COLD FRONT OVER THE PLAINS. A LOW LEVEL THERMAL RIDGE CROSSES THE MID MISSISSIPPI VALLEY SUNDAY WITH H8 TEMPS PEAKING IN THE +8 TO +10C RANGE DURING THE AFTERNOON. GOOD MIXING IS ALSO SUGGESTED WITH A TIGHT SLP GRADIENT AHEAD OF THE COLD FRONT. EVEN WITH THE SNOW COVER...WE SHOULD SEE HIGHS TOPPING OUT IN THE MID 30S TO MID 40S. MODELS MOVE THE FRONT THROUGH THE REGION WITH OUT ANY PRECIPITATION SUNDAY NIGHT. THIS LOOKS REASONABLE WITH THE BETTER MOISTURE GETTING PUSHED OUT WELL AHEAD OF THE SYSTEM. THERE IS SOME CONCERN MONDAY WITH THE LESS PHASED ECM SOLUTION LIFTING A PIECE OF THE UPPER TROF OUT OF TEXAS...SENDING A SURFACE LOW NORTHEAST THROUGH THE OHIO VALLEY. THE ECMS PRECIP SHIELD WITH THIS FEATURE JUST MISSES THE SOUTHEAST CWFA MONDAY. MODELS DO AGREE ON A WEAK S/W RACING SOUTHEAST THROUGH THE DAKOTAS AND MN MONDAY AND MONDAY NIGHT WITH THE LATEST RUNS MOVING IT/S WEAK SURFACE LOW THROUGH IA AND FAVOR THE NORTHEAST CWFA FOR SOME LOW POPS FOR LIGHT SNOW. JUST A QUICK SHOT OF COLD AIR IS EXPECTED BEHIND THIS FEATURE WITH THE COLDEST TEMPS EXPECTED WEDNESDAY MORNING WITH LOWS IN THE SINGLE DIGITS AND TEENS. FOR THE END OF THE WEEK ANOTHER S/W MOVING OUT OF THE CANADIAN ROCKIES WILL SEND A SURFACE LOW EAST ALONG THE U.S. CANADIAN BORDER...DRAGGING A COLD FRONT THROUGH THE REGION WEDNESDAY NIGHT OR THURSDAY MORNING. THE FRONT SHOULD MOVE THROUGH DRY WITH A LARGE AREA OF HIGH PRESSURE OVER THE WESTERN GULF BLOCKING ANY MOISTURE RETURN. BUT THE NORTHEAST COULD SEE SOME LIGHT SNOW IN THE CYCLONIC FLOW AROUND THE SURFACE LOW AS IT MOVES INTO EASTERN CANADA THURSDAY NIGHT AND FRIDAY. MODELS SHOW THE SYSTEM DRAGGING DOWN ANOTHER CHUNK OF ARCTIC AIR WITH BOTH THE ECM AND GFS BRINGING H8 TEMPS AS COLD AS -22C OVER THE AREA THURSDAY NIGHT. THIS COULD RESULT IN SUBZERO TEMPERATURES OVER THE NORTH BY SATURDAY MORNING. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1135 PM CST FRI JAN 10 2014 CONDITIONS EXPECTED TO TREND FROM LIFR/VLIFR TO IFR OVERNIGHT AND EARLY SATURDAY AM. MAY SEE VFR CONDITIONS DEVELOP IN DECREASING CLOUDS BY MID SATURDAY AM THROUGH MIDDAY... BUT THEN MORE LOW CLOUDS WITH MVFR CIGS ARE SHOWN BY SEVERAL MODELS TO PROPAGATE BACK DOWN ACROSS EASTERN IOWA AND NORTHWEST ILLINOIS SATURDAY AFTN ESPECIALLY NORTH OF I-80 WITH SECONDARY COLD FRONT. ALL AREAS EXPECTED TO CLEAR AND RETURN TO VFR BY SATURDAY NIGHT AS HIGH PRESSURE BUILDS IN. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...DENSE FOG ADVISORY UNTIL 6 AM CST SATURDAY FOR BENTON-BUCHANAN- CEDAR-CLINTON-DELAWARE-DES MOINES-DUBUQUE-HENRY IA-IOWA- JACKSON-JEFFERSON-JOHNSON-JONES-KEOKUK-LEE-LINN-LOUISA- MUSCATINE-SCOTT-VAN BUREN-WASHINGTON. FREEZING RAIN ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR BENTON- BUCHANAN-CLINTON-DELAWARE-DUBUQUE-JACKSON-JONES-LINN. IL...DENSE FOG ADVISORY UNTIL 6 AM CST SATURDAY FOR BUREAU-CARROLL- HANCOCK-HENDERSON-HENRY IL-JO DAVIESS-MCDONOUGH-MERCER- PUTNAM-ROCK ISLAND-STEPHENSON-WARREN-WHITESIDE. FREEZING RAIN ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR CARROLL-JO DAVIESS-STEPHENSON-WHITESIDE. MO...DENSE FOG ADVISORY UNTIL 6 AM CST SATURDAY FOR CLARK-SCOTLAND. && $$ UPDATE...05 SYNOPSIS...08 SHORT TERM...08 LONG TERM...DLF AVIATION...05
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1128 PM CST FRI JAN 10 2014 .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 255 PM CST FRI JAN 10 2014 BEGINNING TO LOOK LIKE FZDZ MIGHT BE ABOUT ALL THE MPX AREA SEES FROM THE UPPER WAVES WORKING ACROSS THE CENTRAL CONUS NOW. THE PROBLEM CONTINUES TO BE A DELAYED PHASING OF A NORTHERN STREAM WAVE CURRENTLY HEADING FOR NW MN AND A SRN STREAM WAVE THAT IS MOVING UP OUT OF IA TOWARD WI. THESE TWO SYSTEMS DO NOT REALLY LOOK TO BECOME ONE UNTIL SAT MORNING OVER MICH. THE RUB THERE IS THAT THE SRN STREAM WAVE IS THE ONE WITH ALL OF THE MOISTURE AND THEREFORE PRECIPITATION AND WITH THESE SYSTEMS NOT PHASING UNTIL SATURDAY...WE ARE SEEING THE PRECIPITATION MOVING THROUGH FASTER AND FARTHER EAST TODAY/TONIGHT. RUNS OF THE HOPWRF TODAY HAVE BEEN PROGRESSIVELY INCHING A DEFORMATION BAND EAST WITH TIME AND WITH THE 15Z RUN ALL 4 MEMBERS ARE NOW SHOWING A BAND OF ENHANCED PRECIP FALLING FROM ABOUT DECORAH...IA UP TOWARD WAUSAU...EAST OF THE MPX CWA. ON RADAR...THERE IS A CLUSTER OF HIGHER RETURNS THAT MATCHES UP WELL WITH THESE PRECIPITATION SWATHS AND WITH THE HRRR PICKING UP ON THIS SCENARIO NOW AS WELL...CONFIDENCE IS BEGINNING TO INCREASE THAT THIS SYSTEM WILL BE A DUD IN THE SNOWFALL DEPARTMENT FOR THE MPX AREA. WITH ALL OF THAT SAID...STILL ANTICIPATE SOME LIGHT SNOW TO DEVELOP MAINLY EAST OF THE I-35 CORRIDOR AS THE SFC TROUGH THAT IS STILL HANGING OUT ALONG THE MN/DAKOTAS BORDER SLIDES EAST THIS EVENING...MEETING UP WITH THE DEEPER MOISTURE STREAMING NORTH INTO WI. HAVE FOLLOWED THE IDEA OF THE HRRR AND OTHER HI-RES MODELS WHICH SHOW JUST LIGHT QPF/SIMULATED REFLECTIVITY DEVELOPING OVER ERN MN WITHIN THE NEXT COUPLE OF HOURS BEFORE SLOWLY SLIDING EAST. SAID SFC TROUGH WILL CLEAR THE MPX AREA AROUND 9Z...WITH ANY SNOW LIKELY CUTTING OFF AFTER THAT. BASICALLY...THERE MIGHT BE ONE OR TWO LUCKY FOLKS OUT THERE THAT PICK UP A HALF INCH OF SNOW OUT OF THIS...OTHERWISE IT IS JUST A SEA OF LOW CLOUDS AND HAZE UNTIL THE SFC TROUGH CLEARS AND WINDS BECOME WNW. AS FOR TONIGHT...FOLLOWED THE IDEA OF THE RAP AND NAM OF SKIES SCATTERING OUT AT LEAST FOR A LITTLE WHILE AS BOUNDARY LAYER WINDS BECOME MORE WRLY...MUCH LIKE WHAT HAS BEEN SEEN TODAY ACROSS THE DAKOTAS. THINKING WE WOULD SEE SOME CLEARING...DID FOLLOW THE IDEA MOST GUIDANCE SHOWS OF KNOCKING LOWS BACK INTO THE LOWER TEENS FOR MUCH OF THE AREA WEST OF TWIN CITIES. NOT MUCH TO SAY ABOUT SATURDAY...OTHER CLOUDS CURRENTLY MOVING INTO NRN NODAK SWEEP THROUGH HERE DURING THE MORNING/EARLY AFTERNOON WITH HIGHS STILL LOOKING TO NESTLE UP INTO THE 5-10 DEGREES ABOVE NORMAL RANGE. SO MADE ONLY MINOR CHANGES TO EXISTING FORECAST...MAINLY JUST BLENDING IN LATEST BIAS CORRECTED MODEL DATA. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 255 PM CST FRI JAN 10 2014 LONGER TERM TRENDS CONTINUE TO INDICATE RATHER PROGRESSIVE UPPER LEVEL FLOW PATTERN OVER THE AREA DURING THE PERIOD. COOLING TREND APPEARS TO TAKE HOLD BY LATE IN THE PERIOD AS ANOTHER AREA OF COLD AIR DIVES SOUTHEAST ALONG THE AMPLIFYING HUDSON BAY VORTEX. A LIGHT MIX OF PRECIPITATION MAY STILL OCCUR UNDER STRONG WAA PATTERN UNDER STRONG 130KT H25 JET SUNDAY INTO SUNDAY NIGHT. WARMING ALOFT INDICATES FAVORABLE THICKNESS FOR POSSIBLE LIGHT ZR-/ZL- INTO THE DAY AS SURFACE TEMPERATURES WARM THROUGH THE LOWER 30S DURING TH DAY. WHATEVER IS LEFT INTO THE EVENING/SUNDAY OVERNIGHT WILL CHANGE OVER TO SNOW...BUT ONLY LIGHT QPF AMOUNTS ARE INDICATED. DETERMINISTIC EC AND GFS CONTINUE TO SHOW ANOTHER WEAK CLIPPER TYPE SYSTEM DIVING SOUTHEAST ALONG WEAK SURFACE BOUNDARY... AFFECTING MAINLY SOUTHERN CWA DURING THE MONDAY INTO MONDAY NIGHT PERIOD. TIMING IS IN QUESTION...WITH THE 12Z GFS A BIT FASTER THAN THE 12Z EC. WONT GET TOO CUTE ON TIMING OF THIS SYSTEM NOW...BUT WE COULD SEE SOME LIGHT SNOW ACCUMULATION WITH THIS AS IT PASSES THROUGH. BRIEF SHOT OF COLDER AIR ARRIVES FOR TUESDAY/TUESDAY NIGHT AHEAD OF NEXT SURGE OF PACIFIC AIR FOR WEDNESDAY. MODELS INDICATE THE NEXT MAIN SURGE OF ARCTIC AIR ARRIVES THURSDAY AND WILL LINGER THROUGH THE END OF THE PERIOD AS THE EASTERN CONUS TROUGH DIGS SOUTHEAST. AT THE MOMENT...IT DOESNT APPEAR TO BE AS COLD AS THE LAST WILL HAVE TO MONITOR DEVELOPMENT OF THE TROUGH INTO NEXT WEEK. COULD SEE SOME LIGHT SNOW/SNOW SHOWERS WITH THIS AS IT DIVES SOUTHEAST AND THE COLD AIR ARRIVES. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1054 PM CST FRI JAN 10 2014 SEVERAL COMPLICATING ISSUES ACRS THE COVERAGE AREA AFFECTING THE TAFS TONIGHT. IN WRN MN...FOG. IN CENTRAL-ERN MN...FOG AND LOW CEILINGS. IN WRN WI...LOW CEILINGS AND LEFTOVER -FZDZ/-SN. OVERALL...IFR-OR-WORSE CONDITIONS WILL BE COMMONPLACE THROUGH THE FIRST SEVERAL HOURS OF THE TAF PERIOD. CONDITIONS MAY WELL BE FLUCTUATING SO AMENDMENTS MAY WELL BE FAIRLY FREQUENT TO UPDATE THE FIRST 6 HRS. BY DAYBREAK...PRECIP AND FOG SHOULD NO LONGER BE ISSUES BUT SOME MVFR CIGS MAY REMAIN...ESP IN WRN WI. OVER MN...THE SHIFT TO WLY WINDS WILL AID IN BRINGING IN SOME DRIER AIR TO HELP SCOUR OUT THE LLVL MOISTURE. VFR CONDS THRU LATE MRNG THEN ANOTHER SWATH OF LOWER CLOUDS ON THE BACKSIDE OF AN UPR TROF WILL MOVE THRU. CLOUDS LOOK TO BE MAINLY LOW-END VFR...POSSIBLY MVFR. BY LATE DAY...VFR CONDS PREVAIL WHILE WINDS BACK TO SSE AND DIMINISH IN SPEED. KMSP...IFR CONDS TO START WITH STILL SOME OCNL BOUTS OF -FZDZ FOR THE FIRST COUPLE OF HOURS...THEN CONDS IMPROVE THRU THE REST OF THE PRE-DAWN HOURS. VFR FOR MIDDAY...THEN ADDITIONAL CEILINGS RETURN MID-TO-LATE DAY. AM NOT THINKING THESE WILL BE MVFR BUT THAT POSSIBILITY CERTAINLY CANNOT BE RULED OUT. AFTER THE SWATH OF MIDLVL CEILINGS EXIT BY LATE AFTN...VFR CONDS EXPECTED TMRW NIGHT. WINDS WILL SWING AROUND TO WLY...WHICH WILL AID IN CLEARING OUT THE LOW CLOUDS AND FOG TNGT...THEN REMAIN WLY THRU THE DAY BEFORE BACKING SAT EVE. /OUTLOOK FOR KMSP/ SUN...VFR. WINDS SW 10-15 KTS. MON...VFR. CHC MVFR/-SN OVERNIGHT. WINDS W-SW 5-10 KTS. TUE...VFR. CHC MVFR CIGS. WINDS NW 15G25 KTS. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. && $$ SHORT TERM...MPG LONG TERM...DWE AVIATION...JPC
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1152 PM CST Fri Jan 10 2014 .UPDATE: Issued at 945 PM CST Fri Jan 10 2014 The new swath of rain with the warm conveyor was centered from just west of Litchfield through the St. Louis metro into southeast MO. It is moving rather quickly to the northeast and should exit much if not all of MO before midnight as the progressive upstream trof continues to advance east and dry air moves in aloft. Adjustments this evening were just temporal trends with the rain and temperatures. During the overnight period and more specifically after 09z I increased the pops through central and northeast MO. There is a growing area of rain and snow across eastern KS due to what appears to be a mid-upper level deformation zone. The RAP and HRRR rotate this precipitation into the aforementioned area after 09z and weaken it by 12z. My pops while higher than the previous forecast may not be high enough if it maintains more identity. Glass && .SHORT TERM: (Through Tonight) Issued at 1217 PM CST Fri Jan 10 2014 Focus will be precip tonight, but in two areas. First, the ongoing RA that will be moving out of the region late tonight. The second, is precip associated with the upper trof currently over the Plains. Believe ongoing precip will be confined to the ern half of the CWA at the beginning of the period. Precip shud continue pushing quickly ewd and only be in the far ern counties by Midnight. Not much change in the way of QPF thru tonight. The other area of precip may be across nrn portions of the CWA late tonight as the upper trof moves thru. Mdls are in fairly good agreement with timing/placement of this feature. However, mdls suggest a lack of available moisture will prevent any precip by the time the trof reaches the CWA. POPs or mention of flurries may need to be added to these areas late tonight. As for temps, expect temps to remain steady or even rise ahead of the cdfnt as it moves thru the area. Resultant temps are around the warmer guidance as airmass behind the fnt is not that cold based on upstream obs. Tilly .LONG TERM: (Saturday through Next Friday) Issued at 251 PM CST Fri Jan 10 2014 (Saturday through Monday) After further critique of the latest guidance for Sat, have decided to add slight chance for SN continuing into the early morning hours. There is still a lot of uncertainty if enuf moisture will remain to produce SN, but believe it is worthy of slight chances. If the SN does occur, with the relatively warm bndy temps, do not anticipate much in the way of accumulations. Next system reaches the region on Sun night into Mon as another deep trof approaches the region. For now, have kept POPs in the low chance range due to a fair amount of uncertainty among guidance regarding strength and placement of the trof and sfc reflection. Continued trend twd warm temps with upper ridging moving into the region. (Tuesday through Friday) Period begins with a focus on precip chances on Tues as a clipper approaches the area. Each mdl has a different soln with vast differences between them. Given the system is a clipper, will likely have low confidence in any given soln until much closer to Tues. For now, will just add slight chances for SN and refine the fcst as time approaches. As for temps, have tried to trend twd a compromise of guidance. Have low confidence in any single soln as area remains under meridional flow, producing warming and cooling periods. Tilly && .AVIATION: (For the 06z TAFs through 06z Saturday Night) Issued at 1128 PM CST Fri Jan 10 2014 Satellite imagery and upstream surface obs suggest that cigs will remain IFR to MVFR overnight before improving to VFR during the morning due to the arrival of drier air and the onset of mixing. The cold front which has already moved through KCOU/KUIN will reach KSUS/KCPS within a few hours. Winds will turn westerly behind the front and remain westerly for most of the TAF period. Decreasing winds near an approaching surface high, very moist grounds, and radiational cooling will probably cause fog and/or stratus to redevelop on Saturday night. A period of rain or snow is possible at KCOU this morning between 09-12z, but confidence is too low to include in the TAF. Later shifts will need to monitor upstream trends across KS and western MO. Specifics for KSTL: Satellite imagery and upstream surface obs suggest that currently variable cigs will settle to MVFR overnight before improving to VFR during the morning due to the arrival of drier air and the onset of mixing. Winds will turn westerly behind a cold front within a few hours and then remain westerly for most of the TAF period. Decreasing winds near an approaching surface high, very moist grounds, and radiational cooling will probably cause fog and/or stratus to redevelop on Saturday night. Kanofsky && .LSX WATCHES/WARNINGS/ADVISORIES: MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS RALEIGH NC
305 AM EST SAT JAN 11 2014 .SYNOPSIS...AS HIGH PRESSURE MOVES FARTHER OFFSHORE...A VIGOROUS COLD FRONT MOVES ACROSS THE REGION TODAY AND THIS EVENING. HIGH PRESSURE QUICKLY BUILDS BACK INTO THE REGION SUNDAY BEHIND THE COLD FRONT. ANOTHER COLD FRONT APPROACHES FROM THE WEST LATE MONDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 305 AM SATURDAY... DEEP UPPER TROUGH WAS MOVING EAST ON WATER VAPOR IMAGERY EARLY THIS MORNING TOWARD THE MISSISSIPPI RIVER...AND THIS TROUGH WILL MOVE ACROSS CENTRAL NORTH CAROLINA OVERNIGHT TONIGHT. IN ADVANCE...THE LATEST SURFACE ANALYSIS SHOWED A WEDGE FRONT ESSENTIALLY BISECTING CENTRAL NORTH CAROLINA...WITH TEMPERATURES STILL LINGERING IN THE UPPER 30S IN THE IMMEDIATE TRIAD...TO THE MID 60S TOWARD KCTZ. IN FACT...THE TEMPERATURE AT KRDU WAS IN THE MID 40S WHILE THE TEMPERATURE AT THE NWS OFFICE TO THE EAST ACROSS TOWN WAS NEAR 60. THE WEDGE SHOULD START TO BREAK DOWN IN ADVANCE OF THE COLD FRONT...BUT IT COULD BE A SLOW PROCESS...AND WILL STAY ON THE COOLER SIDE OF GUIDANCE WITH THE HIGH TODAY IN THE TRIAD. FROM U.S. 1 EAST...ANTICIPATE ENOUGH WARM ADVECTION THAT TEMPERATURES SHOULD RISE TO VALUE NEAR 70 TO THE MID 70S...WARMEST FAR SOUTHEAST. WILL NOTE RECORD HIGHS AT KRDU OF 75 AND KFAY OF 79 BOTH SET IN 1930. NOT GOING THAT WARM...AND NONE OF THE GUIDANCE SUGGESTS THAT LEVEL OF WARMTH CURRENTLY. THE WARMTH...THOUGH...WILL HELP IN DEVELOPING SOME INSTABILITY DURING THE LATE MORNING AND AFTERNOON. THE GFS IS MORE UNSTABLE THAN THE RAP...WITH THE FORMER SUGGESTING LIFTED INDICES FALLING TO -2C TO -4C ALONG AND EAST OF U.S. 1 BY THE AFTERNOON...ALONG WITH 700J/KG OF CAPE IN THE LOWEST KM AS A STRONG 700MB SHORTWAVE MOVES INTO THE AREA...AHEAD OF A 110KT 500MB JET AND WINDS OF AT LEAST 65KT AT 850MB. THE RAP ONLY FORECASTS ABOUT 200J/KG OF SURFACE-BASED CAPE...BUT EVEN WITH THE CAPE FORECAST OF THE RAP...AND THE LIMITED MIXING ON THE GFS BUFR SOUNDINGS...THERE COULD EXIST ENOUGH BOUNDARY LAYER INSTABILITY WITH THE STRONG WINDS ALOFT AND 60KT OF 0-3KM SHEAR THAT A STRONGLY FORCED LINE OF SHOWERS...WITH ISOLATED THUNDER...MOVES ACROSS CENTRAL NORTH CAROLINA MAINLY THIS AFTERNOON. THE SPC OUTLOOK CONTINUES TO NOTE A SLIGHT RISK FOR CENTRAL NORTH CAROLINA AND THIS SEEMS REASONABLE...AND WILL CONTINUE THE MENTION OF A DAMAGING WIND THREAT FOR MOST OF CENTRAL NORTH CAROLINA IN THE HWO. AS DRY AND MORE STABLE AIR MOVES WEST TO EAST ACROSS THE AREA...ANY SEVERE THREAT SHOULD DIMINISH BY EARLY EVENING IN THE COASTAL PLAIN. CANNOT COMPLETELY RULE OUT AN ISOLATED TORNADO GIVEN THE 0-3KM HELICITY FORECAST BY THE GFS BETWEEN 100 AND 300M2/S2... WITH SIMILAR VALUES FORECAST BY THE LATEST RAP. IN TERMS OF OTHER ITEMS TO CONSIDER...MANY AREAS OF FOG THIS MORNING ACROSS CENTRAL NORTH CAROLINA BUT VISIBILITIES WERE PRIMARILY ABOVE A HALF-MILE. A FEW POCKETS OF VISIBILITY FROM A HALF-MILE OR LESS. FOR NOW AM NOT PLANNING A DENSE FOG ADVISORY...BUT WILL CONTINUE TO MONITOR THIS. IN ADDITION...AS THE SURFACE GRADIENT TIGHTENS THIS AFTERNOON AHEAD OF THE FRONT...WILL CONTINUE TO ANTICIPATE WITH MIXING GRADIENT WIND GUSTS TO 35MPH. TONIGHT...MORE STABLE AIR MOVES INTO CENTRAL NORTH CAROLINA WITH THE GFS BUFR SOUNDINGS FAIRLY SUBSIDENT BY 06Z. LINGERING SHOWERS...AND A POSSIBLE THUNDERSTORM IN THE COASTAL PLAIN EARLY TONIGHT... DIMINISH WEST-TO-EAST AS PRECIPITABLE WATER VALUES FALL TO AROUND A QUARTER-INCH BY 12Z SUNDAY. THE STRONG UPPER TROUGH WILL BE PUSHING THROUGH CENTRAL NORTH CAROLINA AND EXPECT A FEW MID-LEVEL CLOUDS ASSOCIATED WITH IT...BUT MODELS ARE STRONGLY DRY DURING THE OVERNIGHT HOURS. OVERNIGHT LOWS UPPER 30S IN THE TRIAD TO THE MID 40S TOWARD KCTZ...AROUND 40 IN THE U.S. 1 CORRIDOR. && .SHORT TERM /SUNDAY THROUGH TUESDAY/... AS OF 305 AM SATURDAY... SUNDAY...SUBSIDENCE CONTINUES OVERALL...WITH PRECIPITABLE WATER VALUES FALLING BELOW A QUARTER-INCH SUNDAY UNDER BUILDING HIGH PRESSURE SURFACE AND ALOFT. WITH MIXING...THE GFS BUFR SOUNDINGS SUGGEST A FEW WIND GUSTS TO AROUND 20KT SUNDAY BEFORE WINDS SLACKEN AS THE MID-LEVEL TROUGH PULLS AWAY TO THE EAST AND SURFACE HIGH PRESSURE BUILDS OVERHEAD. HIGHS IN THE MID 50 TO AROUND 60. SUNDAY NIGHT...THE MID-LEVEL RIDGE AXIS MOVES EAST WHICH COULD ALLOW A RETURN OF A FEW HIGH CLOUDS INTO CENTRAL NORTH CAROLINA DURING THE OVERNIGHT HOURS AS THE UPPER FLOW BACKS SOUTHWEST. THE RELATIVELY STRONGER 300MB WINDS REMAIN SOUTHWEST OF CENTRAL NORTH CAROLINA SUNDAY NIGHT THROUGH 12Z MONDAY...THOUGH...SO ANY HIGH CLOUDS THAT MOVE IN SHOULD BE SCATTERED TO POSSIBLY THIN BROKEN AT TIMES. OVERNIGHT LOWS IN THE 30S...COOLEST AND CLOSE TO FREEZING IN SOME OF THE TYPICALLY COOLER LOCATIONS OF THE NORTHEAST PIEDMONT AND THE NORTHERN COASTAL PLAIN. -DJF A SHORTWAVE TROUGH IN PROGRESSIVE FLOW ALOFT WILL AMPLIFY ACROSS THE PLAINS AND MS VALLEY MONDAY...WITH PRECEDING SOUTHWESTERLY FLOW ALOFT YIELDING CONSIDERABLE MID-HIGH CLOUDINESS DOWNSTREAM ACROSS THE CAROLINAS AND MIDDLE ATLANTIC. DESPITE THE INCREASING CLOUDINESS...TEMPERATURES WILL TREND ABOVE AVERAGE BY SOME 8-12 DEGREES...IN RETURN SSW FLOW AROUND PROGRESSIVE SURFACE HIGH PRESSURE IN THE WESTERN ATLANTIC. MODEL DIFFERENCES THAT DEVELOP EARLY IN THE PERIOD - SIMILAR TO THOSE EVIDENT DURING THE PAST SEVERAL MODEL ITERATIONS - CONTINUE TO PLAGUE THE MON NIGHT-TUE TIME FRAME. THAT IS...THE ECMWF AND ASSOCIATED ENSEMBLE MEMBERS FAVOR A SLOWER TROUGH PROGRESSION...WITH MORE SOUTHERN STREAM DOMINANCE...AND CONSEQUENTLY ALLOW FOR MORE APPRECIABLE MOISTURE TRANSPORT FARTHER INLAND THAN A MORE SUPPRESSED/OFFSHORE GFS AND GFS ENSEMBLE MEAN SOLUTION. WILL FOLLOW PREVIOUS FORECAST CONTINUITY AND CONTINUED WPC PREFERENCE TOWARD THE WETTER-FOR CENTRAL-NC ECMWF SOLUTIONS...AND AS SUCH...CARRY A HIGH CHANCE TO LOW LIKELY PROBABILITY OF RAIN MON NIGHT-TUE...WITH PRECIPITATION AMOUNTS IN THE QUARTER TO HALF INCH RANGE. CONTINUED RELATIVELY MILD...WITH TEMPERATURES ABOUT 10 DEGREES ABOVE AVERAGE. && .LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/... AS OF 305 AM SATURDAY... MODEL DIFFERENCES CONTINUE INTO THE MEDIUM RANGE/LONG TERM...WITH THE ECMWF AND ASSOCIATED ENSEMBLE MEMBERS ON THE SLOWER AND MORE AMPLIFIED ENVELOPE OF SOLUTIONS REGARDING A TRAILING SHORTWAVE TROUGH AND ASSOCIATED STRONG CLIPPER SURFACER LOW FORECAST TO MIGRATE ACROSS THE UPPER MIDWEST AND LOWER GREAT LAKES...AND SOME DEGREE OF SECONDARY COASTAL CYCLOGENESIS ALONG THE MIDDLE ATLANTIC COAST CENTERED AROUND WED. SINCE THE SHORTWAVE TROUGH IN QUESTION IS AN ELONGATED AXIS OF SHEAR VORTICITY SOUTHWEST OF THE ALEUTIANS...IN A REGION OUTSIDE OF THE DOMAIN OF THE EC AND GFS MODEL DATA AVAILABLE TO RAH...IT IS DIFFICULT TO HAVE A PREFERENCE TOWARD ONE CLUSTER OF SOLUTIONS OVER THE OTHER. BOTH CLUSTERS OF SOLUTIONS ARE RELATIVELY MOISTURE-STARVED THROUGH A DEEP LAYER AT OUR LATITUDE - NOT SURPRISING SINCE THE PRIMARY VORT AND CLIPPER SFC LOW PASS TO OUR NORTH - SO WE WILL ACCORDINGLY MAINTAIN THE FLAVOR OF THE PREVIOUS FORECAST...WITH JUST A SLIGHT CHANCE OF PRECIPITATION CENTERED ON THE DAY WED. THERMAL PROFILES INDEED APPEAR QUITE COLD...PARTICULARLY ABOVE THE BOUNDARY LAYER (IN THE H85-7 LAYER)..CHARACTERISTIC OF STEEP LAPSE RATE ALOFT/MOISTURE-STARVED SYSTEMS. THE NON-SPECIFIC MENTION OF "RAIN OR SNOW" WILL SUFFICE UNTIL A CLEARER MODEL PREFERENCE AND/OR CONSENSUS BECOMES APPARENT. CLEARING IN BRIEF MODIFIED POLAR HIGH PRESSURE WILL FOLLOW FOR THU...IN ADVANCE OF YET ANOTHER SHARPENING TROUGH ALOFT AND APPROACHING MOISTURE-STARVED SURFACE FRONTAL ZONE IN CONTINUED STRONGLY PROGRESSIVE FLOW ALOFT...FOR THE END OF THE WEEK. && .AVIATION /06Z SATURDAY THROUGH WEDNESDAY/... AS OF 105 AM SATURDAY... WIDESPREAD IFR TO VLIFR CONDITIONS CONTINUE OVER CENTRAL NORTH CAROLINA EARLY THIS MORNING WITH RAIN BECOMING MORE SCATTERED FOR A PERIOD AS IT TRANSITIONS TO A MORE SHOWERY CHARACTER. LOW-LEVEL WIND SHEAR REMAINS A CONCERN...ALTHOUGH MARGINAL BASED ON THE CRITERIA DUE TO THE GRADUAL VEERING AND INCREASE OF THE WIND SPEED WITH HEIGHT ALOFT. STILL...CONTINUING THE MENTION OF LOW-LEVEL WIND SHEAR THROUGH THE EARLY MORNING HOURS FROM THE TRIAD THROUGH THE TRIANGLE...DEEPER INTO THE WEDGED AIR MASS. DURING SATURDAY...A VIGOROUS COLD FRONT MOVES ACROSS THE AREA WITH A LIKELY BAND OF SHOWERS...AND AT LEAST ISOLATED THUNDERSTORMS. GUSTY WINDS WITH THE BAND ARE POSSIBLE IN THE TRIAD...BUT INSTABILITY INCREASES TO THE EAST...AND IT IS NOTED IN THE FORECASTS FOR KRDU...KFAY...AND KRWI WEST GUSTS TO 40KT DURING THE AFTERNOON WHEN IT IS EXPECTED A STRONGLY-FORCED LINE WILL MOVE ACROSS CENTRAL NORTH CAROLINA. RAPID DRYING TAKES PLACE LATE THIS AFTERNOON AND THIS EVENING...WITH CONDITIONS RETURNING TO VFR WEST-TO-EAST ACCOMPANIED BY A NOTICEABLE WEST WIND THAT REMAINS FOR MUCH OF THE NIGHT. WEST-NORTHWEST GUSTS TO AROUND 20KT ARE POSSIBLE WITH MIXING SUNDAY BEFORE WINDS DIMINISH SUNDAY AFTERNOON. FOR MONDAY THROUGH WEDNESDAY...A PERIOD OF SUB-VFR CONDITIONS IS POSSIBLE MONDAY NIGHT INTO EARLY TUESDAY WITH A CHANCE OF LIGHT RAIN. ANOTHER PERIOD OF SUB-VFR CONDITIONS COULD OCCUR LATE TUESDAY NIGHT INTO EARLY WEDNESDAY. LIGHT PRECIPITATION IS POSSIBLE THEN AS WELL. && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...DJF NEAR TERM...DJF SHORT TERM...DJF/MWS LONG TERM...MWS AVIATION...DJF
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
332 AM EST SAT JAN 11 2014 .SYNOPSIS... LOW PRESSURE OVER THE CENTRAL GREAT LAKES REGION WILL MOVE NORTHEAST TO WESTERN QUEBEC THIS EVENING. A COLD FRONT SOUTH FROM THE LOW WILL MOVE EAST ACROSS THE AREA TODAY. SUNDAY...HIGH PRESSURE OVER THE GULF COAST STATES WILL BUILD ACROSS THE AREA. ANOTHER COLD FRONT WILL FOLLOW ON MONDAY. && .NEAR TERM /THROUGH TODAY/... USED A COMBINATION OF THE NAM AND THE HRRR FOR THE NEAR TERM FROM THE PREDAWN HOURS THROUGH THE DAY. WILL BEGIN WITH CATEGORICAL POPS EVERYWHERE BUT WILL BEGIN TO TAPER ALMOST IMMEDIATELY FROM THE WEST BEHIND THE COLD FRONT. RADAR SHOWING WHAT THE EARLIER HRRR HINTED AT WITH THE FIRST SURGE HAVING EXITED TO THE NORTHEAST AND THE SECOND SURGE OF PRECIP MOVING IN. AND YET ANOTHER WAVE NEAR THE OHIO RIVER. EVENTUALLY THIS MAY ALL BLEND TOGETHER EARLY THIS MORNING WITH THE HEAVIEST RAINFALL ACROSS THE CENTRAL COUNTIES OF THE CWA...WITH THE FOCUS MOVING TO THE EASTERN COUNTIES AROUND/AFTER DAWN. BY 15Z BROUGHT POPS TO CHANCE IN THE FAR WEST. MODELS DO SHOW ANOTHER SURFACE TROF/SHORT WAVE ALOFT ROTATING THROUGH THE AREA THAT COULD BRING A FEW SHOWERS TO THE AREA AGAIN IN THE AFTERNOON. AS FOR TEMPS...EXPECT HIGHS TO BE IN THE MORNING WITH TEMPS FALLING DURING MUCH OF THE DAY. && .SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/... AGAIN USED MAINLY NAM TIMING THROUGH THE SHORT TERM BLENDING INTO THE GFS TUESDAY. FOR TONIGHT MODELS SHOW THE UPPER TROF ACROSS THE GREAT LAKE SHIFTING EAST THROUGH THE NIGHT AS A SHORT WAVE RIDGE BUILDS IN. HIGH PRESSURE ACROSS THE GULF COAST STATES WILL ALSO EXTEND NORTH INTO THE OHIO VALLEY. WILL BEGIN WITH CLOUDS ACROSS THE EAST HALF OF THE AREA WHERE THE DEEPEST MOISTURE REMAINS AT 12Z HOWEVER IN THE WEST WILL DROP CLOUDS TO PC IN THE MORNING. FOR THE AFTERNOON WILL DECREASE CLOUDS IN THE EAST AS WELL. NEXT SYSTEM WILL COME MONDAY. LOW PRESSURE WILL MOVE EAST ACROSS ONTARIO MONDAY REACHING JAMES BAY BY EVENING. THE ASSOCIATED COLD FRONT WILL MOVE EAST ACROSS THE AREA DURING THE DAY MONDAY. THE NAM DEVELOPS MOST OF THE PRECIP ACROSS THE EASTERN HALF OF THE AREA AS A SURGE OF MOISTURE MOVING OUT OF THE GULF COAST MERGES WITH THE FRONT MOVING THROUGH THE AREA. THE GFS DOESNT SHOW THIS AS AGGRESSIVELY HOWEVER SO WHILE THE HIGHEST POPS ARE ACROSS THE EAST IN THE AFTERNOON DID BACK OFF LIKELY TO HIGH CHANCE NUMBERS. AFTER A 6 TO 12 HOURS BREAK MODELS BRING A CLIPPER THROUGH THE AREA. THE GFS IS A BIT FASTER AT 12Z TUESDAY WITH THE MOISTURE AND SURFACE LOW SO SPLIT THE DIFFERENCE AND BROUGHT SNOW IN CLOUDS BUT ESSENTIALLY BOTH MODELS WOULD SUGGEST SNOW SOMETIME TUESDAY CONTINUING TUESDAY NIGHT. FAIRLY MILD TEMPS...COOLING OFF MID WEEK. && .LONG TERM /WEDNESDAY THROUGH FRIDAY/... SEASONAL TEMPERATURES WEDNESDAY THROUGH FRIDAY. BETTER AGREEMENT ON THE PATH OF LOW PRESSURE FROM WESTERN CANADA STAYING NORTH OF THE GREAT LAKES FOR THURSDAY. RIDGING WEDNESDAY WILL PROVIDE FOR RELATIVELY FAIR WEATHER...ALTHOUGH A FEW LIGHT SNOW SHOWERS MAY LINGER ACROSS NE OH/NW PA TO START. THE WARM FRONT EARLY THURSDAY MORNING DOES NOT HAVE A BIG PUSH OF WARM AIR WITH IT AND WILL MODERATE TEMPS ONLY TO NEAR FREEZING. AT THIS POINT IT LOOKS LIKE PRECIP ARRIVES THURSDAY NIGHT AND LINGERS INTO FRIDAY. AT THIS POINT AN EASTERN U.S. TROUGH WILL HAVE RETURNED TO END THE WEEK. && .AVIATION /06Z SATURDAY THROUGH WEDNESDAY/... CONFIDENCE IN THIS FORECAST IS PRETTY POOR DUE TO THE RAPID UP AND DOWN SWINGS OF CEILINGS AND VISIBILITIES ACROSS AREA. THIS IS ALL THANKS TO A WARM FRONTAL BOUNDARY ACROSS THE AREA. SOME DOWN SLOPE FLOW IS TAKING PLACE AND THIS SHOULD HELP TO IMPROVE CONDITIONS OVER THE EAST ALONG WITH SOMEWHAT DRIER AIR MOVING INTO THE REGION HELPING TO SUPPRESS RAINFALL. COLD FRONT WILL PUSH THROUGH THE AREA DURING THE DAY TOMORROW AND WE SHOULD SEE IMPROVEMENT IN CEILINGS AND VISIBILITIES FROM WEST TO EAST. MAY EVEN SEE SOME CLEARING AT VERY END OF THE PERIOD FOR FINDLAY. LEFT MENTION OF SNOW OUT FOR NOW DUE TO LIMITED CHANCES THAT IT WILL OCCUR. WINDS SHIFT TO MORE WESTERLY AFTER COLD FRONTAL PASSAGE IN THE AFTERNOON. OUTLOOK...NON VFR LATE SATURDAY NIGHT...ESPECIALLY IN THE SNOWBELT. SOME NON VFR MON THRU WED. && .MARINE... SOUTH FLOW SHIFT SOUTHWEST WITH THE PASSAGE OF A COLD FRONT. SOME COLD AIR ADVECTION MAY AID IN ALLOWING WINDS TO MIX DOWN AND YIELD GALE FORCE WINDS FOR THE EASTERN TWO THIRDS OF THE LAKE. WILL CONTINUE THE GALE WARNING THAT WAS PREVIOUSLY ISSUED FOR LATER THIS AFTERNOON AND EVENING. THIS MAY CAUSE SHIFTING/RIDGING/RAFTING OF ICE ON THE LAKE. SOUTHWEST WINDS DIMINISH FOR SUNDAY AS A RIDGE MOVES OVERHEAD. MONDAYS COLD FRONT WILL ONLY SHIFT WINDS FROM THE SOUTH TO THE SOUTHWEST. LOW PRESSURE FROM THE NORTHERN PLAINS TAKES A PATH ACROSS THE MIDWEST AND LOWER GREAT LAKES EITHER TUESDAY OR WEDNESDAY. WINDS WILL FINALLY GO NORTHWEST AFTER THE PASSAGE OF THIS SYSTEM. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...GALE WARNING FROM 4 PM THIS AFTERNOON TO 5 AM EST SUNDAY FOR LEZ061-144>149-164>169. && $$ SYNOPSIS...TK NEAR TERM...TK SHORT TERM...TK LONG TERM...OUDEMAN AVIATION...LOMBARDY MARINE...OUDEMAN
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
1251 AM EST SAT JAN 11 2014 .SYNOPSIS... AN APPROACHING UPPER LEVEL TROUGH WILL MOVE INTO THE AREA TONIGHT...WITH RAIN EXPECTED TONIGHT AND INTO SATURDAY. A COLD FRONT WILL CROSS THE REGION BY SATURDAY AFTERNOON...LOWERING TEMPERATURES THROUGH SUNDAY. HIGH PRESSURE WILL ENTER THE SOUTHEASTERN STATES ON SUNDAY...WITH RIDGING BRINGING FAIR CONDITIONS TO THE OHIO VALLEY THROUGH EARLY MONDAY. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... MOST LOCATIONS EXPERIENCING WIDESPREAD FOG ACROSS THE NORTHERN MIAMI VALLEY AND EAST CENTRAL INDIANA HAVE SEEN IMPROVING CONDITIONS OVER THE COUPLE HOURS. THEREFORE...THE DENSE FOG ADVISORY HAS BEEN CANCELLED. SOUTH AND EAST OF THE NORTHERN MIAMI VALLEY...JUST A FEW AREAS OF LIGHT PRECIPITATION ARE EXPECTED UNTIL MIDNIGHT...AS THE LEADING EDGE OF A LARGE AREA OF RAIN ARRIVES IN THE SOUTHWESTERN ZONES. PREVIOUS DISCUSSION > INCREASING ISENTROPIC LIFT AHEAD OF A DEEPENING MID- LEVEL TROUGH WILL GRADUALLY LEAD TO AN INCREASE IN PRECIPITATION POTENTIAL THIS EVENING...PRIMARILY FOR THE WESTERN HALF OF THE CWA. DESPITE THE RELATIVELY ABUNDANT LOW-LEVEL MOISTURE...IT IS NOT APPARENT THAT CURRENT ECHOES IN THE SOUTHWEST CWA ARE REACHING THE GROUND...SO MEASURABLE PRECIPITATION MAY STILL BE A FEW HOURS OFF. MOST OF THE IMPACTS FROM THE APPROACHING TROUGH AND COLD FRONT WILL BE COVERED IN THE SHORT TERM DISCUSSION. TEMPERATURES OVERNIGHT ARE EXPECTED TO REMAIN RELATIVELY STEADY FOR A WHILE...BEFORE RISING (ESPECIALLY IN THE SOUTHERN CWA) CLOSER TO DAYBREAK. THE RAP WAS USED AS A BASIS FOR THESE NON-DIURNAL TEMPERATURES...AS IT IS HANDLING THE CURRENT SITUATION WELL. && .SHORT TERM /6 AM THIS MORNING THROUGH SUNDAY NIGHT/... AHEAD OF A MID-LEVEL TROUGH MOVING EAST OUT OF THE MISSISSIPPI VALLEY...A SURFACE LOW WILL TRACK NORTHEASTWARD INTO THE GREAT LAKES REGION ON SATURDAY. THIS WILL BRING A COLD FRONT THROUGH THE OHIO VALLEY BY SATURDAY AFTERNOON. AHEAD OF THE COLD FRONT...THE OHIO VALLEY WILL BE WITHIN A REGIME OF DEEP SOUTHERLY FLOW...ADVECTING A VERY MOIST AIR MASS INTO THE REGION. BY EARLY SATURDAY MORNING...PRECIPITABLE WATER VALUES WILL BE WELL OVER AN INCH ACROSS THE ILN CWA...EXCEEDING 300 PERCENT OF NORMAL FOR JANUARY. THE STRONGEST PUSH OF MOISTURE WILL COME ON THE NOSE OF A LOW LEVEL JET BETWEEN 08Z AND 12Z...FOCUSED PRIMARILY ON THE SOUTHERN AND SOUTHEASTERN SECTIONS OF THE ILN CWA. WITH SOUNDINGS APPEARING MOIST ADIABATIC (AS WOULD BE EXPECTED)...INSTABILITY WILL BE HARD TO COME BY. THERE APPEARS TO BE JUST ENOUGH CONDITIONAL ELEVATED INSTABILITY TO SUPPORT A CHANCE OF THUNDER IN THE SOUTH AND SOUTHEAST CWA EARLY SATURDAY MORNING...AND AT THE VERY LEAST...SOME OF THE SHOWERS WILL LIKELY BE A LITTLE BIT CONVECTIVE IN NATURE. THE LARGER-SCALE MODELS INDICATE PRECIPITATION TOTALS OF GENERALLY JUST UNDER AN INCH...WHILE SOME OF THE MESOSCALE MODELS SHOW AN AXIS OF OVER AN INCH THAT WORKS THROUGH THE SOUTH-CENTRAL PORTIONS OF THE ILN CWA. BASED ON THE APPEARANCE OF SIMULATED REFLECTIVITY ON THE HIGH-RES RUNS...AND THE POTENTIAL FOR SOME ISOLATED ELEVATED CONVECTIVE ELEMENTS...SOME LOCALIZED PRECIPITATION AMOUNTS MAY GET AS HIGH AS AN INCH AND A HALF. BASED ON FLASH FLOOD GUIDANCE AND MMEFS RUNS (USING NAEF/SREF/GEFS INPUT)...IT DOES NOT APPEAR THAT THIS WILL BE ENOUGH RAIN TO LEAD TO SIGNIFICANT FLOODING ISSUES. A FEW ACTION STAGE RIVER READINGS...OR PERHAPS AN ADVISORY OR TWO...MAY NOT BE OUT OF THE QUESTION. NON-DIURNAL TEMPERATURE TRENDS ARE BEING CONTINUED THROUGH SATURDAY...AS COLD FRONTAL PASSAGE OCCURS. DEEP MOISTURE WILL DISAPPEAR AFTER THE FRONT HAS PASSED...BUT POPS WILL BE MAINTAINED AS ADDITIONAL RAIN SHOWERS (MIXING WITH SNOW LATE) APPEAR LIKELY. THIS POST-FRONTAL REGIME (UNDER THE MID-LEVEL TROUGH AXIS) WILL BE CHARACTERIZED BY A MIXED LAYER WITH WEAK AND SHALLOW INSTABILITY...AND ABUNDANT LOW- LEVEL MOISTURE. EVENTUALLY...AS THE NIGHT PROGRESSES...MOISTURE BECOMES SHALLOW ENOUGH THAT ICE CRYSTALS MAY NOT BE ABLE TO FORM. FLURRIES HAVE BEEN INTRODUCED THROUGH SATURDAY NIGHT...BUT IT IS VERY POSSIBLE THAT THIS WILL END UP BEING DRIZZLE (OR EVEN FREEZING DRIZZLE BASED ON SURFACE TEMPS). BY SUNDAY MORNING...RIDGING WILL BE ENTERING THE CWA...WITH SURFACE HIGH PRESSURE BUILDING IN FROM THE SOUTH. THE LOW LEVEL MOISTURE MAY NOT ALLOW CLOUDS TO SCOUR VERY QUICKLY...BUT MOSTLY SUNNY SKIES ARE EXPECTED BY AFTERNOON FOR MOST OF THE CWA (WITH CLOUDS DISSIPATING EARLIER IN THE SOUTH). WITH THE CWA RETURNING TO A WARM ADVECTION PATTERN...TEMPS WILL RISE AGAIN ON SUNDAY...AND STRUGGLE TO EVEN CROSS BACK UNDER THE FREEZING MARK ON SUNDAY NIGHT / EARLY MONDAY MORNING. && .LONG TERM /MONDAY THROUGH FRIDAY/... RAIN WILL BE LIKELY MONDAY AS A SURGE OF GULF MOISTURE MOVES UP A FRONTAL BOUNDARY ON A SOUTHWEST UPPER FLOW. SOME LOCATIONS MAY SEE AN INCH OF RAIN WITH THIS EVENT. RAIN AND SNOW SHOWERS ARE POSSIBLE FOR TUESDAY IN THE NORTHWEST FLOW BEHIND THE FRONT. SNOW SHOWERS MAY LINGER ON WEDNESDAY IN THE COLDER NORTHWEST FLOW. A PERIOD OF DRY WEATHER IS INDICATED FOR THURSDAY WHEN A RIDGE OF HIGH PRESSURE IS FORECAST TO PUSH ACROSS THE REGION. SNOW SHOWERS WILL BE POSSIBLE AGAIN ON FRIDAY DUE TO A TROUGH AND ASSOCIATED MOISTURE AND COLD ADVECTION. TEMPERATURES WILL START ABOVE NORMAL MONDAY AND TUESDAY...WITH HIGHS MAINLY IN THE 40S. COLD ADVECTION WILL PUSH READINGS BELOW NORMAL ON WEDNESDAY AND FRIDAY WITH HIGHS IN THE 20S...WHILE THE RIDGE WILL PROVIDE SOME WARM ADVECTION AND NEAR NORMAL 30S FOR THURSDAY. && .AVIATION /06Z SATURDAY THROUGH WEDNESDAY/... AREA OF SHOWERS WITH EMBEDDED THUNDER WILL CROSS THE TAF SITES IN THE NEXT FEW HOURS. KEPT KDAY OUT OF THE THUNDER ATTM AS THE NARROW AREA OF LIGHTNING STRIKES IN THE HEAVIEST RAIN APPEARS TO COINCIDE STRONGLY WITH THE MODEL TAKE OF 1000-850MB STRONGEST THETA E ADVECTION WHICH WILL REMAIN ALONG AND E OF THE I-71 CORRIDOR AND SHIFT EASTWARD THIS MORNING. WINDS WILL PICK UP IN THE 15-18Z TIME FRAME AS THE COLD FRONT CROSSES THE REGION. SUSTAINED 14-17KT WITH GUSTS TO 25 AND 30KT OUT OF THE WEST WILL PREVAIL FROM THIS TIME THROUGH ABOUT 0-1Z. LOW MVFR CIGS WILL IMPROVE SLIGHTLY DURING THE DAY DUE TO THE STRONGER WINDS AND THEN DROP BACK DOWN TO IFR OVERNIGHT WHEN THE GRADIENT RELAXES SOME. THE H5 TROUGH IS CROSSING THE REGION 3-6Z TOMORROW NIGHT AND SOME SCATTERED SHOWERS OR AT LEAST LOWER CIGS ARE POSSIBLE TOWARDS THE END OF THE TAF PERIOD. OUTLOOK...MVFR CEILINGS LIKELY THROUGH DAYBREAK SUNDAY. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...NONE. KY...NONE. IN...NONE. && $$ SYNOPSIS...HATZOS NEAR TERM...HATZOS/LATTO SHORT TERM...HATZOS LONG TERM...CONIGLIO AVIATION...FRANKS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1105 PM CST FRI JAN 10 2014 .SHORT TERM...(TONIGHT THROUGH SATURDAY NIGHT) ISSUED AT 206 PM CST FRI JAN 10 2014 MAIN CONCERNS IN THE SHORT TERM WILL BE DEALING WITH WINTRY MIX INTO TONIGHT. A WINTER WEATHER ADVISORY IS IN EFFECT UNTIL 6 AM SATURDAY. WATER VAPOR IMAGERY SHOWING A DEEP MID-LEVEL TROUGH MOVING ACROSS CENTRAL CONUS AT THIS TIME. AT THE SURFACE...A TROUGH EXTENDED FROM ALONG THE DAKOTAS/MN BORDER...INTO EASTERN NEBRASKA/KANSAS. THESE FEATURES WERE PRODUCING ISENTROPIC LIFT AND MOISTURE TRANSPORT INTO THE AREA FOR A WINTRY MIX OF PRECIPITATION AT GROUND LEVEL. RADAR SHOWING RETURNS ACROSS THE ENTIRE AREA WITH AREAS OF MAINLY DRIZZLE AND FREEZING DRIZZLE BEING REPORTED. SOME SLEET WAS ALSO SHOWING UP ACROSS PARTS OF NORTHEAST IA. OTHERWISE...TEMPERATURES ACROSS THE AREA RANGED FROM THE MIDDLE 20S ACROSS NORTH CENTRAL WI...TO THE LOWER 30S ACROSS NORTHEAST IA INTO FAR SOUTHWEST WI. LOOK FOR THE MID-LEVEL/SURFACE TROUGH TO MOVE EAST THROUGH THE AREA TONIGHT...WITH MOST OF THE PRECIPITATION CHANGING OVER TO LIGHT SNOW THIS EVENING. THE ONLY EXCEPTION WILL BE ACROSS PORTIONS OF NORTHEAST IA INTO FAR SOUTHWEST AND CENTRAL WI WHERE THERE WILL BE LACK OF ICE ISSUES IN THE COLUMN AND WARMER AIR ALOFT. SO...A MIXTURE OF DRIZZLE...FREEZING DRIZZLE...SLEET AND LIGHT SNOW WILL STILL BE POSSIBLE THERE. WHERE THE SNOW FALLS...GENERALLY ALONG AND NORTHWEST OF A TOMAH/LA CROSSE/OELWEIN LINE...PERHAPS 1/2-1 INCH IS POSSIBLE. OF NOTE IS THE RAP SHOWING LOSS OF ICE IN THE CLOUD AGAIN AFTER MIDNIGHT...HINTING AT THE POSSIBILITY OF MIXING WITH OR CHANGING OVER TO LIGHT FREEZING DRIZZLE OVERNIGHT. WITH THIS IN MIND...WILL KEEP WINTER WEATHER ADVISORY GOING THROUGH 6 AM SATURDAY. OVERNIGHT LOWS ARE EXPECTED TO DIP INTO THE 20S. MAY STILL BE SOME LIGHT SNOW/FLURRY ACTIVITY EARLY ON SATURDAY MORNING...BUT LOOKING FOR ANY LINGERING PRECIPITATION TO SHIFT OFF TO THE EAST BY NOON AS A RIDGE OF HIGH PRESSURE BUILDS IN FROM THE PLAINS. AREAS WEST OF THE MISSISSIPPI WILL LIKELY SEE A GOOD AMOUNT OF SUNSHINE BY AFTERNOON WITH CLEARING PUSHING EAST OF THE MISSISSIPPI LATER IN THE AFTERNOON. HIGHS ON SATURDAY EXPECTED TO RISE INTO THE UPPER 20S TO LOWER 30S. RIDGE OF HIGH PRESSURE WILL CONTINUE TO MOVE EAST ACROSS THE AREA SATURDAY NIGHT FOR QUIET WEATHER CONDITIONS. WILL SEE SOME INCREASE IN MID/HIGH LEVEL CLOUDS THOUGH AHEAD OF A WARM FRONT PUSHING EAST OUT OF THE NORTHERN/CENTRAL PLAINS. OVERNIGHT LOWS WILL BE IN THE LOWER TO MIDDLE TEENS. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 206 PM CST FRI JAN 10 2014 MILDER PACIFIC ORIGIN AIR WILL PUSH INTO THE AREA ON SUNDAY WITH HIGHS EXPECTED TO TOP OFF IN THE LOWER/MIDDLE 30S. UNFORTUNATELY... INCREASING CLOUD COVER AND SOUTHWEST WINDS IN THE 10 TO 20 MPH RANGE WILL MAKE IT FEEL MORE LIKE THE LOWER/MIDDLE 20S. A COLD FRONT WILL THEN PUSH INTO/THROUGH THE AREA SUNDAY NIGHT. THIS WILL GIVE THE AREA A CHANCE OF A WINTRY MIX WITH A TRICKY THERMAL PROFILE IN PLACE. COLDER AIR UNDERCUTTING RELATIVELY MILDER AIR ALOFT MAY PRODUCE A LIGHT WINTRY MIX OF FREEZING RAIN/SLEET/SNOW AS OVERNIGHT LOWS FALL INTO THE TEENS/LOWER 20S. FORTUNATELY... PRECIPITATION LOOKS VERY LIGHT...BUT ANY FREEZING PRECIPITATION COULD CAUSE HEADACHES. WILL CONTINUE TO TO KEEP A CLOSE EYE ON THIS. COLDER AIR WILL FILTER INTO AREA MONDAY THROUGH TUESDAY AS A DEEP MID-LEVEL TROUGH CARVES OUT OVER THE CENTRAL CONUS. SOME EMBEDDED ENERGY WITHIN THE TROUGH WILL GIVE THE AREA A CHANCE FOR LIGHT SNOW AS WELL. LOOK FOR HIGHS MONDAY AND TUESDAY IN THE 20S WITH LOWS MONDAY NIGHT IN THE UPPER SINGLE DIGITS AND TEENS. ANOTHER SHOT AT SOME LIGHT SNOW LOOKS TO OCCUR WEDNESDAY NIGHT INTO THURSDAY AS WARM AIR ADVECTION TAKES PLACE AHEAD OF LOW PRESSURE MOVING ACROSS SOUTHERN CANADA. SOME LINGERING LIGHT SNOW OF FLURRY CHANCES WILL BE SEEN THURSDAY NIGHT AS THE COLD FRONT FROM THIS LOW PASSES THROUGH. MUCH COLDER AIR IS ON TAP GOING INTO FRIDAY AS ANOTHER MODIFIED SHOT OF ARCTIC AIR MAKES ITS WAY INTO THE AREA. HIGHS ARE EXPECTED TO DROP BACK INTO THE TEENS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1105 PM CST FRI JAN 10 2014 THE -SN/-FZDZ CONTINUED TO SHIFT EAST LATE THIS EVENING...AND WILL LIKELY BE EAST OF KRST AROUND 06Z. TRENDS SUGGEST CLOSER TO 09Z FOR KLSE. CLOUDS WILL BE TRICKY AS THEY CONTINUE TO BOUNCE BETWEEN IFR AND MVFR. SOME SUB 500 FT WOULD ALSO SEEM LIKELY AT KRST. MEANWHILE...LATEST FOG/STRATUS SATELLITE IMAGERY DEPICTS A CLEARING WEDGE BEHIND THE PASSING COLD FRONT. THIS COULD REACH KRST BY 12Z. MORE CLOUDS FOUND ACROSS NORTHERN MN...ROTATING SOUTH/SOUTHEAST POST A LOW OVER SOUTHERN CANADA. RAP/NAM/GFS ALL SUGGEST THAT THE CLOUDS WOULD SLIDE ACROSS THE TAF SITES BY LATE MORNING...EXITING BY MID/LATE AFTERNOON. GOING TO TRY AND TIME A TEMPO GROUP FOR WHEN A BREAK IN THE CIGS IS MORE LIKELY THIS MORNING...ALTHOUGH CONFIDENCE IS SHAKY. PRESSURE GRADIENT WILL TIGHTEN SAT...AND THERE COULD BE SOME GUSTS IN THE AFTERNOON...ESPECIALLY IF THE ANTICIPATED CLEARING OCCURS. ANTICIPATING VFR CONDITIONS SAT NIGHT. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...WINTER WEATHER ADVISORY UNTIL 6 AM CST SATURDAY FOR WIZ017-029- 034-041>044-053>055-061. MN...WINTER WEATHER ADVISORY UNTIL 6 AM CST SATURDAY FOR MNZ096. IA...WINTER WEATHER ADVISORY UNTIL 6 AM CST SATURDAY FOR IAZ010-011- 029-030. && $$ SHORT TERM...DAS LONG TERM....DAS AVIATION.....RIECK
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
335 AM PST SAT JAN 11 2014 .DISCUSSION...AS OF 3:06 AM PST SATURDAY...A 975 MB LOW IS DEEPENING WEST OF SEATTLE BEFORE IT BEGINS TO FILL AND MOVE INLAND. A COLD FRONT EXTENDS SOUTHWARD FROM THE PARENT LOW AND WILL MOVE INTO FAR NORTHERN CALIFORNIA TODAY. LIGHT RAIN WAS REPORTED THE LAST FEW HOURS IN CRESCENT CITY AND ALL EYES WILL BE ON THIS PRECIP AS IT SLOWLY MAKES ITS WAY TOWARDS THE NORTH BAY BY LATE THIS MORNING OR EARLY AFTERNOON. MODEL CONSENSUS REMAINS GOOD WITH THE NAM/GFS AND EVEN THE RAP/HRRR SHORT RANGE MODELS SHOWING LIGHT RAINFALL BETWEEN 18-00Z THIS AFTERNOON. THE BEST CHANCE FOR SEEING SHOWERS WILL BE ACROSS SONOMA COUNTY BUT CANT COMPLETELY RULE OUT SHOWERS OR SPRINKLES FROM THE GOLDEN GATE DOWN TO THE SANTA CRUZ MOUNTAINS. THERE IS LITTLE OR NO COLD ADVECTION OR JET DYNAMICS THIS FAR SOUTH AND EXPECT NO PRECIP FOR THE SANTA CLARA VALLEY AND EAST BAY VALLEYS WITH SUCH A WEAK BOUNDARY. IN A NORMAL YEAR RAINFALL LIKE THIS WOULD HARDLY BE WORTH MENTIONING AS NORMAL RAINFALL PER DAY THIS TIME OF YEAR IS ALMOST 0.25 PER DAY IN THE NORTH BAY. PERHAPS VENADO WILL SEE UPWARDS OF A QUARTER INCH BUT ONLY EXPECT A FEW HUNDREDTHS FOR MOST REPORTING LOCATIONS FROM THE GOLDEN GATE NORTH WITH TRACE AMOUNTS SOUTH OF THE CITY. ANY LINGERING SHOWERS WILL QUICKLY END BY THIS EVENING WITH SOME LINGERING BOUNDARY LAYER MOISTURE ALLOWING SOME FOG TO FORM OVERNIGHT. HIGH PRESSURE WILL BEGIN TO BUILD SUNDAY BUT TEMPERATURES ARE FORECAST TO STAY IN THE LOW TO MID 60S. UNSEASONABLY STRONG HIGH PRESSURE STRENGTHENS MONDAY AND CONTINUES FOR MOST OF NEXT WEEK. 850 MB TEMPS ARE PROGGED TO REACH 16 CELSIUS BY TUESDAY MORNING WHICH WOULD REPRESENT THE 99TH PERCENTILE EVER RECORDED AT THE OAKLAND UPPER AIR SITE SHOULD IT VERIFY WITH DATA GOING BACK TO 1948. THERE WILL BE A PERIOD OF AT LEAST MODERATE OFFSHORE WINDS IN THE HILLS LATE SUNDAY NIGHT INTO MONDAY. STILL DOESN`T LOOK LIKE WIND ADVISORY CRITERIA WILL BE MET. FROM MONDAY AFTERNOON INTO TUESDAY SUSTAINED BUT LIGHT EASTERLY FLOW WILL DEVELOP OVER ALMOST ALL OF COASTAL CALIFORNIA WITH THE BOUNDARY LAYER BECOMING VERY DRY. RECORD OR NEAR RECORD HIGHS WILL BE POSSIBLE MONDAY THROUGH WEDS WITH TUESDAY LOOKING LIKE THE WARMEST DAY AT THIS TIME WITH LOCAL DOWN-SLOPE WARMING BEING MAXIMIZED. IRONICALLY THE BIGGEST IMPACT MAY END UP BEING FIRE WEATHER CONCERNS. PLEASE SEE FIRE WEATHER BELOW FOR MORE ON THAT. THE RIDGE WILL STAY IN PLACE AT LEAST THROUGH FRIDAY ALTHOUGH THE WINDS LOOK TO TURN ONSHORE BY THE END OF THE WEEK. THE MODELS HINT AT A FRONT BUMPING INTO THE RIDGE BY NEXT WEEKEND BUT ALSO SHOW ANY PRECIP FALLING APART BEFORE MOVING ONSHORE. AT THIS POINT WERE WATCHING THE EXTENDED 2 WEEK FORECAST FOR ANY HOPE OF A PATTERN CHANGE. THE 240 HOUR FORECAST FROM THE ECMWF SHOWS A STRONG 180 KT JET ACROSS THE PACIFIC WHILE THE 12-16 DAY GFS RUNS SHOW SOME ENERGY BREAKING THROUGH THE RIDGE. ITS GETTING HARD BUT WILL HAVE TO STAY PATIENT AND SEE IF THE PATTERN BREAKS AT ALL AFTER MLK WEEKEND. && .AVIATION...AS OF 3:30 AM PST SATURDAY...LOW CONFIDENCE AND COMPLICATED FORECAST AS A MIX OF CLOUDS COVER THE REGION WITH A FORECASTED FROPA LATER TODAY. THROUGH THE MORNING HOURS...MOSTLY VFR CONDITIONS WITH MID-HIGH LEVEL CLOUDS. SPEAKING OF HIGH CLOUDS THEY ARE MAKING IT DIFF TO SEE ANY STRATUS OR FOG ON THE SATELLITE. KSTS IS STILL REPORTING FOG. WILL KEEP FOG AT KSTS THROUGH THE MORNING HOURS. FOR SF BAY...DELAYED ANY CIGS/STRATUS UNTIL ALMOST 15Z. NOT EVEN THAT CONF STRATUS WILL ACTUALLY DEVELOP. A FRONT WILL SWEEP THROUGH 18-20Z WITH POSS -RA FOR KSTS AND VCSH AROUND SF BAY AND NO RAIN MENTION S OF SF BAY. CLEAR SKIES BEHIND THE FRONT WITH POSS PATCHY FOG TONIGHT. VICINITY OF KSFO...VFR TO START THEN DEV CIGS AROUND 15Z...PT SOUNDS AND HRRR MODEL REALLY MOISTEN THE LOW LEVELS. POSS CIGS AND VCSH LATER THIS AFTERNOON WITH THE FRONTAL PASSAGE. WINDS WILL INCREASE SLIGHTLY AS WELL. VFR CONDITIONS BEHIND THE FRONT. LOW CONF. KSFO BRIDGE APPROACH...SIMILAR TO KSFO. MONTEREY BAY AREA TERMINALS...PATCHY FOG LINGERS...BUT NONE BEING REPORTED AT KSNS/KMRY. WILL KEEP AN EYE ON THIS...OTHERWISE VFR CONDITIONS. POSS CIGS LATER TODAY AS THE FRONT APPROACHES. MEDIUM CONF. && .MARINE...AS OF 3:30 AM PST SATURDAY...NO REAL CHANGE IN THE FORECAST. MODELS STILL SEEM ON TRACK TO GENERATE BUILDING NORTHWEST SWELL OVER THE COASTAL WATERS LATER TODAY.NW SWELL 14 TO 18 FEET TONIGHT/SUNDAY WITH A PERIOD OF 15-16 SECONDS. THIS WILL TRANSLATE TO LARGER SURF ALONG THE BEACHES. GIVEN THE PERIOD AND SWELL HEIGHT SQUARED SEAS SEEM PLAUSIBLE. SWELLS QUICKLY SUBSIDE SUNDAY INTO MONDAY. && .FIRE WEATHER...AS OF 3:06 AM SATURDAY...SOME LIGHT RAIN TODAY IN THE NORTH BAY BUT IN GENERAL NOT EXPECTING WIDESPREAD WETTING RAINS (GREATER THAN A TENTH). NORTHEAST WINDS WILL DEVELOP ACROSS THE NORTH AND EAST BAY HILLS LATER SUNDAY NIGHT INTO MONDAY. EVENT LOOKS MODERATE IN STRENGTH WITH 925 MB WINDS IN THE 15-30 KT RANGE. RH VALUES WILL INITIALLY REMAIN HIGH...AROUND 40% WITH MORE NOTED DRYING OCCURRING LATER MONDAY AFTERNOON INTO TUESDAY. BY TUESDAY THE COMBINATION OF RECORD WARMTH...RECORD DRY FUELS AND DRY EASTERLY FLOW WILL AT THE VERY LEAST ELEVATE FIRE DANGER AND FIRE WEATHER CONCERNS EVEN THOUGH STRICT RED FLAG CRITERIA MAY NOT BE MET. SOUTHERN CALIFORNIA MAY BE DEALING WITH A SANTA ANA AND FIRE RESOURCES AT A MINIMUM GIVEN THE TIME OF YEAR. CURRENT RH...TEMP AND WIND TRENDS BY TUESDAY LOOK EERILY SIMILAR TO WHEN THE PFEIFFER FIRE STARTED LAST MONTH IN BIG SUR. && .CLIMATE...RECORD HIGH SUMMARY FOR NEXT WEEK: CITY MON 1/13/14 TUES 1/14/14 WEDS 1/15/14 ----------------------------------------------------------------- KENTFIELD 65 IN 1994 68 IN 1924 67 IN 1945 SAN RAFAEL 68 IN 2009 68 IN 1967 73 IN 1967 NAPA 81 IN 1924 72 IN 1924 70 IN 1966 SAN FRANCISCO 72 IN 2009 69 IN 2009 73 IN 2009 SFO AIRPORT 72 IN 2009 67 IN 1948 69 IN 1974 OAKLAND DT 78 IN 2009 70 IN 2009 75 IN 2009 OAKLAND AP 69 IN 2009 65 IN 2009 74 IN 2009 RICHMOND 69 IN 2012 66 IN 1959 72 IN 2009 LIVERMORE 73 IN 2009 68 IN 2009 75 IN 1920 MOUNTAIN VIEW 71 IN 2009 73 IN 2009 72 IN 2009 SAN JOSE 75 IN 2009 73 IN 2009 73 IN 2009 GILROY 73 IN 2009 74 IN 2009 72 IN 2012 MONTEREY 77 IN 2009 76 IN 2009 76 IN 2009 SANTA CRUZ 80 IN 1948 81 IN 1975 75 IN 2009 SALINAS 84 IN 2009 80 IN 2009 79 IN 2009 KING CITY 83 IN 2009 76 IN 1981 82 IN 2009 && .MTR WATCHES/WARNINGS/ADVISORIES... .TDAY...SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM FROM 3 PM SCA...PT PINOS TO PT PIEDRAS BLANCAS 10-60 NM FROM 3 PM && $$ PUBLIC FORECAST: RWW AVIATION: MM MARINE: MM CLIMATE: RC/RWW 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 MOUNT HOLLY NJ
1040 AM EST SAT JAN 11 2014 .SYNOPSIS... AN INTENSIFYING LOW PRESSURE SYSTEM OVER THE UPPER PENINSULA OF MICHIGAN WILL MOVE NORTHEAST TOWARD JAMES BAY IN CANADA TODAY. ITS ASSOCIATED COLD FRONT WILL CROSS THE REGION TONIGHT. HIGH PRESSURE WILL THEN BUILD OVER THE AREA SUNDAY AND MONDAY, FOLLOWED BY ANOTHER COLD FRONT ON TUESDAY. A SECONDARY COLD FRONT IS EXPECTED TO MOVE THROUGH THE AREA WEDNESDAY WITH A LOW PRESSURE SYSTEM POSSIBLY DEVELOPING ALONG IT NEAR OUR FORECAST AREA. A HIGH PRESSURE SYSTEM FROM THE SOUTHERN ROCKIES WILL THEN NOSE INTO THE REGION ON THURSDAY. AN ARCTIC COLD FRONT IS FORECAST TO MOVE THROUGH THE AREA LATER FRIDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... SHARP TEMPERATURE BOUNDARY ACROSS THE AREA HAS BEEN ONE OF THE FORECAST CHALLENGES THIS MORNING. STRONG S WINDS AND MUCH MILDER TEMPERATURE LIE ON THE WARMER SIDE OF THIS BOUNDARY. HAVE USED LATEST LAV AND RUC GUIDANCE TO BEST CAPTURE FORECAST TRENDS. ADDED ISOLATED THUNDER TO NW HALF OF FORECAST AREA THRU 18Z AS SOME ISOLATED LIGHTNING STRIKES WERE DETECTED IN THE HEAVIER PRECIPITATION. VERY HIGH DEWPOINTS OVER COLD MARINE WATERS HAVE RESULTED IN WIDESPREAD FOG AND THAT WAS ADDED TO THE GRIDDED FORECAST WITH VISIBILITIES A HALF MILE OR LESS. STARTING TO SEE RESPONSE FROM SMALLER CREEKS AND STREAMS IN NW PART OF FORECAST AREA FROM RAIN SO FAR. MORE DETAILS IN HYDROLOGY SECTION. PREVIOUS DISCUSSION FOLLOWS. LOW PRESSURE WILL MOVE FROM THE UPPER GREAT LAKES THIS MORNING NORTHEASTWARD INTO SOUTHERN CANADA BY TONIGHT. AN ATTACHED COLD FRONT WILL APPROACH THE WESTERN AREAS LATE THIS AFTERNOON. A DEEP MOIST SRLY FLOW WILL BE ACROSS THE AREA THROUGH THE DAY...AND SEVERAL SHORT WAVES WILL BRING PERIODS OF RAIN AND PSBLY A FEW TSTMS (SOUTH) TO THE REGION. POPS ARE CATEGORICAL THROUGH THE DAY. THE GREATEST CHC FOR THUNDER IS MOSTLY SOUTH (DELMARVA/SRN NJ) WHERE GREATER INSTABILITY WILL RESIDE. SPC HAS THESE AREAS IN THE SGT CHC FOR THUNDER TODAY. WINDS JUST OFF THE DECK ARE RATHER STRONG TODAY...THE DEGREE OF MIXING SHOULD NOT BE THAT GREAT WITH THE WARMER AIR ARRIVING OVER A COOLER SFC AIR MASS...ALTHOUGH A WIND ADV WAS CONSIDERED...WE DECIDED INSTEAD TO ISSUE AND SPS WITH THE MENTION OF GUSTY WINDS NEAR TSTMS TODAY. SPOTTY GUSTS AROUND 40-45 MPH POSSIBLE. TEMPS TODAY WILL CONTINUE THE SLOW UPWARD TREND AS OF LATE. TEMPS OVER THE SRN AREAS (WHICH ARE ALREADY IN THE 50S) SHOULD REACH THE MID 60S...WHILE THEN NRN AREAS WILL REACH THE LOW/MID 50S. QPF WILL AVERAGE AROUND 1.0 TO 1.5 INCHES ACROSS MOST AREAS TODAY AND EARLY TONIGHT...LOCAL 2.0 INCH AMTS ARE POSSIBLE. SEE HYDRO SECTION BELOW FOR MORE INFO. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SUNDAY/... CONDITIONS WILL IMPROVE OVERNIGHT AS THE COLD FRONT PASSES OFF THE COAST 01Z-03Z. WINDS WILL BECOME WRLY AND PCPN WILL END FROM W TO E. TEMPERATURES WILL DROP BACK THROUGH THE 40S (SOUTH) AND INTO THE LOW/MID 30S OVER THE NRN AREAS. PCPN WILL END AS RAIN IN ALL AREAS WITH THE COLDER AIR ARRIVING LATER AT NIGHT. WINDS WILL BE SOMEWHAT GUSTY WITH GUSTS 15-20 MPH EXPECTED OVERNIGHT. && .LONG TERM /SUNDAY THROUGH FRIDAY/... A VERY ACTIVE WEATHER PATTERN IS EXPECTED IN THE LONG TERM AS WE HEAD BACK TOWARD A COLDER REGIME. THE GFS INITIALIZATION LOOKED BETTER THAN THE WRF-NMMB, THE 500MB TROF IS DEEPER. THE 850MB AND 925MB INITIALIZATION AVERAGED ABOUT A DEGREE TOO LOW. THIS IS A TENDENCY THAT HAS BEEN AROUND FOR A COUPLE OF NIGHTS AND PROBABLY ONE OF THE REASONS FOR MORE SNOW NORTHWEST YESTERDAY. FARTHER INTO THE LONG TERM, THE MEDIUM RANGE MODELS ARE STARTING TO COME CLOSER WITH DOUBLE BARREL THREATS TUESDAY AND WEDNESDAY AND A CANADIAN OR ARCTIC CFP AT THE END OF THE DETERMINISTIC PERIOD. HERE WE TOOK A MODELING CONSENSUS UNTIL THE DETAILS CAN BE SORTED BETTER. THE TUESDAY SYSTEM`S TROF THAT IS NOW IN THE GULF OF ALASKA SHOULD GET INTO THE DENSER SOUNDING NETWORK ON SUNDAY. A BRISK BUT DRY DAY FOR SUNDAY. WITH THE NORTHWEST FLOW OFF ONTARIO AND AT LEAST A HIGH ENOUGH INVERSION, WE DID INCLUDE SOME SNOW FLURRIES FOR THE POCONOS. ELSEWHERE, THE FCST SOUNDINGS ARE NOT EXPECTED TO BE REACHED AND MOSTLY SUNNY SKIES SHOULD OCCUR. GUIDANCE HAS BEEN EDGING COOLER AND WE LOWERED MAX TEMPS SLIGHTLY, MORE IN LINE WITH GFS MOS THAN NAM MOS. IF THERE IS GOING TO BE A RADIATIONAL COOLING NIGHT, IT WILL BE SUNDAY NIGHT AS THE RIDGE AXIS GETS CLOSEST TO OUR CWA UNDER CLEAR SKIES. THE CAA IS ALSO DONE. WE WENT WITH THE LOWER STAT GUIDANCE IN OUTLYING/MORE RURAL AREAS AND A COMPROMISE ELSEWHERE. A SOUTHWEST FLOW OF MILDER AIR ON MONDAY. THIS REBOUND MAY BE TEMPERED BY SOME RETURN FLOW MOISTURE (CLOUDS) AS BY THEN THE RIDGE AXIS WILL BE EAST OF OUR REGION. BASED ON FCST 925MB TEMPS, WE REMAINED OPTIMISTIC ABOUT THE COASTAL PLAIN LOCATIONS REACHING THE 50S. SO WE ARE AT OR SLIGHTLY ABOVE STAT GUIDANCE. THE NEXT PCPN EVENT IS SLATED FOR MONDAY NIGHT AND TUESDAY. THE GFS REMAINS AMONG THE FASTEST. MOST OF THE OTHER MODELS 500MB TROF IS DEEPER AND THIS TIME OF YEAR DEEPER SOLUTIONS NORMALLY PREVAIL. SO WE SLOWED THE TIMING DOWN CLOSER TO THE ECMWF. DEEPER ALSO MEANS WETTER WITH MORE GULF MOISTURE INVOLVEMENT. WE WILL KEEP A BUNCH OF EYES ON THIS FACET. PTYPE LOOKS TO BE MAINLY RAIN. SLOWER TIMING ALSO MEAN HIGHER TEMPS AND WE KEPT MINS AND MAX TEMPS CLOSE TO CONTINUITY. THERE SHOULD BE A PCPN BREAK ON TUESDAY NIGHT BEFORE THE NEXT COLD FRONT ARRIVES ON WEDNESDAY. HERE THE GFS REMAINS FASTER AND DOES NOT DIG THE NEXT NEXT TROF AS MUCH AS OTHER MEDIUM RANGE MODELS. THE ECMWF WHILE IT REMAINS STRONGER WITH THE COLD AIR CYCLOGEN ALONG THE FRONT, HAS BACKED AWAY FROM THE DEEPER/MORE SOUTHERN DEVELOPMENT IT HAD LAST NIGHT. ONE OF THE REASONS IS THE CLOSED LOW OVER EASTERN QUEBEC HAS DP/DTING BEEN LIFTING NORTHWARD WITH EACH SUCCEEDING RUN. THIS HAS DEFACTOED THE NAO TO BE LESS NEGATIVE AND THUS A MORE NORTHERN DEVELOPMENT. THIS IS FAR FROM BEING ETCHED IN STONE AND THIS ONE WOULD BE COLD ENOUGH TO HAVE SOME SNOW OCCUR. AFTER THIS LOW DEPARTS, HIGH PRESSURE WILL BUILD INTO THE REGION. WHILE TEMPERATURES SHOULD RETURN CLOSER TO NORMAL, THIS HIGH`S ORIGIN IS FROM THE PACIFIC. SO UNLIKE LAST WEEK`S VERSION, THIS AIR MASS HAS MORE OF ITS COLDNESS (RELATIVE TO NORMAL) IN THE UPPER HALF OF THE TROPOSPHERE. THE NEXT COLD FRONT IS SCHEDULED FOR FRIDAY. THIS ONE MAY BE MOISTURE STARVED. BUT THE ENSUING HIGH BEHIND THIS FRONT IS COMING FROM WESTERN CANADA AND WILL BRING EVEN COLDER AIR BACK INTO THE REGION. PLEASE DONT CURB YOUR ENTHUSIASM. && .AVIATION /16Z SATURDAY THROUGH WEDNESDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. POOR FLYING CONDITIONS AT MOST SITES THIS MORNING AND EXPECTED INTO THIS AFTERNOON WITH PERIODS OF IFR CONDITIONS IN LOW CEILINGS AND VISIBILITIES IN FOG AND RAIN. A LOW LEVEL JET IS IN PLACE AND WILL CONTINUE FOR MUCH OF THE DAY. TWO THOUSAND FT WINDS IN THE 50 TO 60 KNOT RANGE. A FEW TSTMS MAY OCCUR THIS AFTERNOON SOUTH/EAST...BUT THEY WERE NOT PLACED IN THE TAFS ATTM. COLD FRONT WILL APPROACH THE WRN TERMINALS 21-23Z. TONIGHT...THE COLD FRONT WILL CROSS THE DEL VALLEY 23Z-01Z AND THE OFF TH COAST 01Z-03Z. WINDS WILL SHIFT TO WRLY AND REMAIN GUSTY FOLLOWING THE FRONT. THE SHOWERS WILL END FROM W TO E AND THEN CIGS/VSBYS WILL IMPROVE BACK TO VFR A FEW HOURS AFTER FROPA. SKIES MAY IMPROVE BACK TO FEW/SCT BY DAWN SUNDAY. OUTLOOK... SUNDAY AND SUNDAY NIGHT...VFR. WEST-NORTHWEST WINDS 15-20 KNOTS AND GUSTY, DIMINISHING AT NIGHT. MONDAY...PREDOMINATELY VFR. GUSTY SOUTHWEST WINDS DEVELOPING. MONDAY NIGHT AND TUESDAY...VFR GIVING WAY TO POSSIBLE MVFR IN RAIN. POSSIBLY SNOW POCONO AIRPORTS. TUESDAY NIGHT...A VFR PERIOD. CONFIDENCE OF TIMING BETWEEN SYSTEMS IS LOW. WEDNESDAY...MVFR TO IFR CONDITIONS POSSIBLE WITH A GREATER INFILTRATION OF SNOW AS A PRECIPITATION TYPE. GUSTY NORTHWEST WINDS LATER WEDNESDAY. && .MARINE... MID-MORNING MARINE FORECAST UPDATE ADDED WIDESPREAD FOG WITH VISIBILITIES DOWN TO A HALF MILE (AND EVEN LOWER IN SOME LOCATIONS) DUE TO MILD HIGH DEW POINT AIR OVER COLD MARINE WATERS. GALE WARNINGS CONTINUE IN PLACE. PREVIOUS DISCUSSION BELOW. MARINE PRODUCTS WERE UPDATED JUST BEFORE 700 AM TO PLACE THE GALE WARNING IN EFFECT. BUOYS ARE ALREADY SHOWING GUSTS APPROACHING GALES...AND THE TREND LOOKS TO CONTINUE. ONE CHANGE MADE TO THE ONGOING FLAGS FOR THE WATERS. THE GALE WARNING FOR THE OCEAN WAS ALSO PLACED OVER DEL BAY WITH THE LOW LEVEL WINDS EXPECTED TO GUST AT THE ELEVATED WIND PLATFORMS OVER THE BAY. THE WINDS AND SEAS WILL STEADILY INCREASE TODAY AS THE SRLY FLOW AHEAD OF THE APPROACHING LOW/FRONT REMAIN OVER THE REGION. OCCASIONAL SHOWERS WILL BE ON THE WATERS THROUGH THE EVENING. THERE IS A CHC FOR A TSTM WITH LOCAL HIGHER WINDS/SEAS OVER ALL THE WATERS THIS AFTERNOON INTO THE EVENING. AREAS OF FOG ARE ALSO EXPECTED WITH THE HIGHER DEW POINTS MOVING ACROSS THE COLD WATERS...THERE MAY BE JUST ENOUGH WINDS TO MIX IT INTO A LOW OVC HOWEVER. CONFID IN LOW VSBY DENSE FOG IS LOW...SO IT WAS NOT PLACED IN THE GRIDS. TONIGHT...WINDS SHIFT WRLY/NWRLY AND THE PCPN ENDS AFTER MIDNIGHT. GALES WILL LIKELY BE REPLACED WITH SCA FLAGS FOR A WHILE LATER TONIGHT. OUTLOOK... SUNDAY...SMALL CRAFT CONDITIONS ARE EXPECTED...DIMINISHING LATE IN THE DAY AS THE CAA WEAKENS AS DOES THE WESTERLY FLOW. MONDAY AND MONDAY NIGHT...POSSIBLE LOW END SMALL CRAFT ADVISORY CRITERIA IN SOUTHERLY FLOW PRECEDING A COLD FRONT. TUESDAY...NEAR SMALL CRAFT ADVISORY CRITERIA ON THE OCEAN AS ANOTHER COLD FRONT MOVES THROUGH. SUB SMALL CRAFT ADVISORY CRITERIA ON DELAWARE BAY. TUESDAY NIGHT AND WEDNESDAY...A POSSIBLE SMALL CRAFT ADVISORY LULL PERIOD WITH AN INCREASING LIKELIHOOD OF SMALL CRAFT ADVISORY CRITERIA RETURNING BEHIND THE PASSAGE OF THE NEXT COLD FRONT. && .HYDROLOGY... ALREADY STARTING TO SEE SOME RESPONSE IN SMALLER CREEKS AND STREAMS TO RAINFALL SO FAR (WHICH HAS BEEN A HALF INCH OR LESS). HEAVIER RAIN LIES AHEAD. ALSO SEEING REPORTS IN SOCIAL MEDIA OF EXTREME PONDING OF WATER FROM RAIN THAT HAS FALLEN SO FAR DUE TO GROUND BEING FROZEN. THIS WILL PROMOTE HIGHER LEVELS OF RUNOFF FROM TODAY`S RAIN, LEADING TO A HIGHER RISK OF FLASH FLOODING AND MORE SIGNIFICANT STREAM RESPONSE TO RAINFALL. PREVIOUS DISCUSSION BELOW. INTO TONIGHT, A PLUME OF PW VALUES UP TO 1.5 INCHES IS FORECAST TO SURGE ACROSS OUR AREA AHEAD OF A STRONG COLD FRONT. THERE IS A GOOD AMOUNT OF FLOW AND ALSO FORCING TO PRODUCE A SHIELD OF RAIN, SOME OF WHICH WILL BE MODERATE TO HEAVY AT TIMES. THE SYSTEM IS FORECAST TO BE PROGRESSIVE, THEREFORE HEAVIER RAIN SHOULD TEND TO BE MORE LIMITED IN DURATION. HOWEVER, DURING TIMES OF HEAVIER RAIN THERE CAN BE PONDING OF WATER ON ROADWAYS AND SOME FLOODING IN AREAS OF POOR DRAINAGE. THE 1-HOUR AND 3-HOUR FLASH FLOOD GUIDANCE IS THE LOWEST GENERALLY ACROSS THE INTERSTATE 95 CORRIDOR. IN ADDITION, WE HAVE HAD ICE JAMS ON SOME AREA RIVERS AND RIVER/CREEK ICE CONTINUES. IT IS DIFFICULT TO KNOW HOW THE ICE BEHAVES, THEREFORE RAPID CHANGES IN WATER LEVELS CAN OCCUR. A RAPID WARM UP IS ANTICIPATED TODAY WITH THE AREA GETTING WELL INTO THE 50S AND EVEN SOME LOWER TO MID 60S. MUCH OF THE REGION THOUGH HAS LITTLE SNOW COVER SO THERE WILL BE LESS RUNOFF FROM THIS. BUT, THE TOP LAYER OF GROUND IS FROZEN AND UNLESS IT DOES A QUICK THAW, RUNOFF WILL BE VERY EFFICIENT. WALKING OUTSIDE THE OFFICE OVERNIGHT, THERE IS SOME GIVE TO THE GROUND, BUT NOT MUCH YET. SOME ENSEMBLE GUIDANCE INDICATES THAT SEVERAL RIVER FORECAST POINTS GET TO FLOOD STAGE, ESPECIALLY SMALLER STREAMS. THEREFORE, A FLOOD WATCH REMAINS IN EFFECT FOR MOST OF OUR CWA FOR THIS AFTERNOON AND NIGHT. OUTSIDE OF THE FLOOD WATCH, SOME PONDING OF WATER ON ROADS AND POOR DRAINAGE FLOODING IS POSSIBLE. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...FLOOD WATCH THROUGH LATE TONIGHT FOR PAZ054-055-060>062-070- 071-101>106. NJ...FLOOD WATCH THROUGH LATE TONIGHT FOR NJZ001-007>010-012-013- 015>019. DE...FLOOD WATCH THROUGH LATE TONIGHT FOR DEZ001. MD...FLOOD WATCH THROUGH LATE TONIGHT FOR MDZ008. MARINE...GALE WARNING UNTIL 1 AM EST SUNDAY FOR ANZ430-431-450>455. && $$ SYNOPSIS...GIGI/MIKETTA NEAR TERM...SZATKOWSKI/O`HARA SHORT TERM...SZATKOWSKI/O`HARA LONG TERM...GIGI AVIATION...GIGI/SZATKOWSKI/MIKETTA/O`HARA MARINE...GIGI/SZATKOWSKI/MIKETTA/O`HARA HYDROLOGY...SZATKOWSKI/
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
1100 AM EST SAT JAN 11 2014 .UPDATE (REST OF TODAY THROUGH SUNDAY)... 15Z WATER VAPOR AND H4 RAP ANALYSIS SHOW A HIGHLY AMPLIFIED UPPER LEVEL PATTERN IN PLACE ACROSS THE CONUS. MAIN PLAYER FOR OUR FORECAST THE NEXT 24 HOURS WILL IS A DEEP AND SHARP LONGWAVE TROUGH EJECTING EASTWARD FROM THE CENTRAL PLAINS INTO THE EASTERN STATES. THE BASE OF THIS TROUGH EXTENDS SOUTHWARD TO THE NORTHERN GULF COAST AND WILL PIVOT INTO THE SOUTHEASTERN STATES THROUGH THE EVENING AND OVERNIGHT HOURS. THIS TROUGH IS "BOOKENDED" BY LONGWAVE RIDGES OVER BOTH THE INTER-MOUNTAIN WEST AND NOW EXITING OFF THE ATLANTIC SEABOARD. AT THE SURFACE...HIGH PRESSURE RIDGE IS BEING SHOVED SOUTH AND EAST OUT OF THE PENINSULA IN RESPONSE TO THE APPROACH OF A SURFACE COLD FRONT AHEAD OF THE UPPER TROUGH. THIS FRONT CURRENTLY EXTENDS DOWN FROM NORTHERN GEORGIA TO THE WESTERN FLORIDA PANHANDLE AND NORTH-CENTRAL GULF OF MEXICO. SOUTHERLY FLOW AHEAD OF THE FRONT IS BRINGING WITH IT A WARM AND HUMID BOUNDARY LAYER. THIS HIGH DEWPOINT AIR OVER THE NOW COOL SHELF WATERS OF THE EASTERN AND NORTHEASTERN GULF OF MEXICO IS RESULTING IN AREAS/WIDESPREAD SEA FOG (SOME VERY DENSE) OVER THE COASTAL WATERS. THE FOG IS MOST PREVALENT TO THE NORTH OF SARASOTA AND CONDITION WILL REMAIN FAVORABLE FOR THE REDUCED VISIBILITIES THROUGH AT LEAST THE EARLY EVENING UNTIL THE COLD FRONT CAN PASS AND CLEAR THE MORE HUMID AIRMASS AWAY. GENERALLY SPEAKING WE LOOK FOR DEWPOINTS TO BE 3-5+ DEGREES WARMER THAN THE SURFACE WATER TEMPERATURES FOR A SIGNIFICANT THREAT OF SEA FOG. AFTER LAST WEEKS "COLD SNAP"...THE SHELF WATERS COOLED OFF CONSIDERABLY AND HAVE ALLOWED THESE CONDITIONS TO BE MET. A MARINE DENSE FOG ADVISORY IS IN EFFECT TO THE NORTH OF ENGLEWOOD THROUGH THE EARLY EVENING AND MULTIPLE REPORTS OF VISIBILITY NEAR ZERO HAVE BEEN RECEIVED THIS MORNING FROM AREAS TO THE WEST OF EGMONT KEY. ENOUGH WITH THE FOG...ON TO THE COLD FRONT LATER TODAY AND TONIGHT. AS MENTIONED ABOVE...THE UPPER TROUGH WILL PIVOT EASTWARD AND FORCE THE COLD FRONT THROUGH THE AREA TONIGHT. LOW/MID LEVEL WAA ALONG WITH DEEP SYNOPTIC FORCING/DCVA/QV CONVERGENCE AHEAD OF THE TROUGH AXIS ARE SUPPORTING MULTIPLE MCS CLUSTERS OF SHOWERS/STORMS FROM GA/AL TO THE NORTH-CENTRAL GULF LATE THIS MORNING. THIS FORCING ALONG WITH A FAVORABLE RRQ JET PLACEMENT WILL SHIFT EASTWARD WITH TIME INCREASING THE CHANCES FOR SHOWERS AND A FEW STORMS TO OUR ZONES NORTH OF TAMPA BAY BY THE LATE AFTERNOON HOURS. THE BEST CHANCES BEFORE SUNSET WILL BE UP TOWARD CITRUS/LEVY COUNTIES. ELSEWHERE...THE SYNOPTIC FORCING WILL NOT ARRIVE DURING THE DAYLIGHT HOURS...BUT AN INCREASINGLY UNSTABLE ENVIRONMENT MAY ALLOW FOR A FEW SCT SHOWERS TO DEVELOP BY LATE AFTERNOON ACROSS THE INTERIOR PENINSULA. SOME OF THE MORE RELIABLE HIGH-RES GUIDANCE MEMBERS SUCH AS THE HRRR ARE HINTING AT THIS POSSIBILITY AND HAVE INCLUDED A 30% CHANCE POP INLAND (JUST IN CASE). DURING THE EVENING HOURS THE BEST SYNOPTIC FORCING ARRIVES OVER THE NORTHERN PENINSULA ALONG WITH THE COLD FRONT/PRE-FRONTAL TROUGH FOR LOW LEVEL FOCUS. THE CHANCES FOR A BAND OF SHOWERS AND STORM IS FAIRLY HIGH AND HENCE SO ARE THE POPS. THE STORM PREDICTION CENTER HAS OUTLOOKED CITRUS AND LEVY COUNTY FOR A SLIGHT RISK OF SEVERE WEATHER THIS EVENING. WHILE IT IS NOT COMPLETELY OUT OF THE QUESTION FOR A FEW STRONGER STORMS...THE LOW LEVEL JET IS QUITE LIMITED THIS FAR SOUTH AND WILL BE STARTING TO EXIT THE AREA. ALSO...HIGHLY QUESTIONABLE IF ANY OF THESE STORMS WILL BE TRULY ROOTED AT THE SURFACE WITH THE FLOW DEVELOPING OFF THE COOLER SHELF WATERS. MORE LIKELY THAT ANY STORMS WILL BE AT LEAST PARTIALLY ELEVATED WHICH WILL FURTHER LIMIT THE WIND THREAT. THIS DOES NOT MEAN THAT BRIEF HEAVY RAIN AND LIGHTNING MAY NOT BE A THREAT WITH ANY STRONGER CELLS SINCE THE OVERALL FORCING FOR ASCENT IS QUITE STRONG. DESPITE THE LIMITING FACTORS...WE WILL CONTINUE TO MONITOR THE LOW LEVEL ENVIRONMENT IN CASE CONDITIONS BECOME MORE FAVORABLE FOR SURFACE BASED PARCELS OVER THE NORTHERN NATURE COAST AS THE DAY PROGRESSES. THE COLD FRONT AND ASSOCIATED CLUSTERS OF SHOWERS/ISOLATED STORMS WILL SHIFT SOUTH AND EAST ACROSS THE AREA THIS EVENING AND BE MAINLY SOUTH OF TAMPA BAY BY THE SECOND HALF OF THE NIGHT. THE CONVECTION WILL ALSO BECOME LESS ORGANIZED AND LIKELY MORE BROKEN WITH TIME AS THE UPPER LEVEL FORCING AND JET DYNAMICS PIVOTS AWAY FROM THE REGION. JUST HAVE CHANCE POPS FOR SHOWERS TO THE SOUTH OF TAMPA BAY AFTER MIDNIGHT AND END ALL RAIN DOWN TO EVEN FORT MYERS BY SUNRISE ON SUNDAY. A DRIER AIRMASS ALONG WITH SEASONABLE TEMPERATURES AND CLEARING SKIES WILL FILL THE REMAINDER OF THE WEEKEND AS HEIGHTS RISE ALOFT OF THE PENINSULA...AND SURFACE HIGH PRESSURE SLIDES EASTWARD INTO THE REGION FROM THE EASTERN GULF. ENJOY YOUR SATURDAY AND WATCH OUT FOR THE FOG ALONG THE COAST. && .AVIATION... EARLY MORNING IFR/LIFR CIGS WITH PATCHY BR ARE NOW LIFTING WITH ONLY IFR CIGS AT SRQ/PIE/TPA. AFT 15Z EXPECT VFR...LCL MVFR CIGS...WITH GUSTY WINDS THROUGH THE AFTERNOON. APPROACHING FRONT WITH MAINLY SHRA ARRIVES TONIGHT WITH SOME MVFR TO IFR CONDITIONS. && .MARINE... A COLD FRONT WILL APPROACH THE AREA THROUGH THE DAY WITH INCREASING SOUTH TO SOUTHWEST WINDS AHEAD OF IT. AREAS OF DENSE MARINE FOG WILL BE PRESENT ACROSS THE FORECAST WATERS UNTIL THE FRONTAL PASSAGE THIS EVENING. HIGH PRESSURE WILL THEN BUILD BACK INTO THE REGION SUNDAY THROUGH MONDAY. THE NEXT COLD FRONT IS EXPECTED TO MOVE THROUGH THE AREA ON TUESDAY WITH ANOTHER PERIOD OF INCREASED WINDS EXPECTED. && .PRELIMINARY POINT TEMPS/POPS... TPA 77 59 72 55 / 40 60 10 10 FMY 83 65 79 57 / 20 40 10 10 GIF 82 58 72 53 / 40 60 10 10 SRQ 78 61 72 53 / 40 60 10 10 BKV 80 52 71 44 / 60 60 10 10 SPG 77 61 70 58 / 40 60 10 10 && .TBW WATCHES/WARNINGS/ADVISORIES... FL...LAKE WIND ADVISORY UNTIL 6 PM EST THIS EVENING FOR COASTAL CHARLOTTE-COASTAL CITRUS-COASTAL HERNANDO-COASTAL HILLSBOROUGH-COASTAL LEE-COASTAL LEVY-COASTAL MANATEE- COASTAL PASCO-COASTAL SARASOTA-DESOTO-HARDEE- HIGHLANDS-INLAND CHARLOTTE-INLAND CITRUS-INLAND HERNANDO-INLAND HILLSBOROUGH-INLAND LEE-INLAND LEVY- INLAND MANATEE-INLAND PASCO-INLAND SARASOTA-PINELLAS- POLK-SUMTER. GULF WATERS...DENSE FOG ADVISORY UNTIL 5 PM EST THIS AFTERNOON FOR ENGLEWOOD TO TARPON SPRINGS OUT 20 NM-ENGLEWOOD TO TARPON SPRINGS OUT 20 TO 60 NM-TARPON SPRINGS TO SUWANNEE RIVER OUT 20 NM-TARPON SPRINGS TO SUWANNEE RIVER OUT 20 TO 60 NM. && $$ UPDATE/MARINE...MROCZKA AVIATION...RUDE
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
720 AM EST SAT JAN 11 2014 ...SEVERE THUNDERSTORMS POSSIBLE THIS AFTERNOON AND EVENING... .SYNOPSIS... A STRONG COLD FRONT WILL SWEEP ACROSS THE REGION THIS EVENING. HIGH PRESSURE WILL BUILD SUNDAY AND QUICKLY MOVE OFF THE COAST MONDAY...BEFORE ANOTHER COLD FRONT MOVES THROUGH THE AREA BY TUESDAY MORNING. HIGH PRESSURE WILL REBUILD DURING THE MIDDLE OF NEXT WEEK...WITH YET ANOTHER COLD FRONT APPROACHING BY FRIDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AN ACTIVE DAY IS ON TAP FOR SOUTHEAST SOUTH CAROLINA AND SOUTHEAST GEORGIA AS A COLD FRONT APPROACHES FROM THE WEST. AHEAD OF THE FRONT...INCREASING WARM AIR ADVECTION BEING DRIVEN BY A STRONG PRE-FRONTAL LOW-LEVEL JET WILL HELP PUSH TEMPERATURES INTO THE LOWER-MID 70S FOR MOST AREAS AWAY FROM THE COAST... WHICH IS ABOUT 10-15 DEGREES ABOVE NORMAL. AS WARM AIR ADVECTION INTENSIFIES...ISOLATED TO SCATTERED SHOWERS WILL LIKELY BREAKOUT AND AFFECT PORTIONS OF THE AREA PRIOR TO THE ARRIVAL OF THE MAIN CONVECTIVE LINE. ATTM IT APPEARS THE MAIN CONVECTIVE LINE... POSSIBLY IN THE FORM OF A STRONG/SEVERE QUASI-LINEAR CONVECTIVE SYSTEM /QLCS/...WILL REACH THE FAR WESTERN ZONES BY EARLY AFTERNOON AND REACH THE COAST BY LATE AFTERNOON OR EARLY THIS EVENING. H3R INSTABILITY PROGS AND NAM/RAP MODIFIED POINT SOUNDINGS SUGGEST SBCAPE VALUES WILL RISE TO 900-1200 J/KG WITH LIFTED INDICES DROPPING AS LOW AS -4 TO -6C. ALTHOUGH MID-LEVEL LAPSE RATES WILL BE POOR...HEALTHY 0-6KM BULK SHEAR OF 50-60 KT INDUCED BY STRONG LOW-LEVEL JETTING COUPLED WITH MODEST INSTABILITY WILL SUPPORT A RISK FOR SEVERE TSTMS WITHIN A TYPICAL MID-JANUARY HIGH SHEAR/LOW CAPE ENVIRONMENT. THE PRIMARY HAZARD RIGHT NOW LOOK TO BE DAMAGING WINDS WITH A RISK FOR ISOLATED TORNADOES WHERE DISCRETE CELLS OR EMBEDDED MESO-VORTICES WITHIN BOWING CONVECTIVE LINE SEGMENTS CAN DEVELOP. RAP 0-1KM HELICITY VALUES INCREASE TO NEAR 300 M2/S2 AND THE HIGH SHEAR/LOW CAPE SHERBS3 TORNADO PARAMETER RISES ABOVE THE BENCH MARK OF 1 UNIT FOR MUCH OF THE AREA...ALL SUGGESTING THERE IS A REASONABLE RISK FOR TORNADOES. FOR TODAY...WILL HIGHLIGHT POPS NEAR 100 PERCENT FOR ALL AREAS WITH THE HIGHEST GRIDDED POPS PLACED WITH THE EXPECTED TIMING/PLACEMENT OF THE EXPECTED CONVECTIVE LINE. HIGHS WILL BE IN THE LOWER TO MID 70S UNDER MAINLY CLOUDY SKIES. WILL INCLUDE DAMAGING WIND AND TORNADO ATTRIBUTES IN ALL GRIDDED AND TEXT PRODUCTS AND HIGHLIGHT A POTENTIAL FOR SEVERE TSTMS IN THE HAZARDOUS WEATHER OUTLOOK. THE WINDOW OF GREATEST SEVERE THREAT LOOKS TO BE 1 PM THROUGH 7 PM. && .SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/... TONIGHT...CONDITIONS WILL RAPIDLY IMPROVE THIS EVENING AS THE PRIMARY CONVECTIVE LINE PUSHES OFFSHORE AND THE COLD FRONT MOVES THROUGH. EXPECT CLEARING TO OCCUR DURING THE EVENING HOURS WITH MAINLY CLEAR SKIES DEVELOPING BY MIDNIGHT...IF NOT SOONER. LOWS WILL RANGE FROM THE LOWER 40S WELL INLAND TO THE UPPER 40S AT THE BEACHES. SUNDAY...DRY HIGH PRESSURE WILL BUILD IN THE WAKE OF THE DEPARTING COLD FRONT...YET PROGRESSIVE FLOW ALOFT WILL PULL THE CENTER OF THE HIGH QUICKLY TOWARD THE NEARBY ATLANTIC WATERS. COLD ADVECTION WILL BE WEAK BEHIND THE FRONT...AND WITH WIND DIRECTIONS REMAINING GENERALLY WEST/SOUTHWEST...EXPECT ONLY A SLIGHT COOLING TREND TO OCCUR. HIGH TEMPERATURES IN THE MID TO UPPER 60S WILL BE COOLER THAN THE PREVIOUS DAY...YET STILL BE WELL ABOVE SEASONAL NORMALS. AN AMPLIFYING LONG WAVE TROUGH ACROSS THE CENTRAL PLAINS AFTER MIDNIGHT WILL SUPPORT BRIEF DOWNSTREAM HEIGHT RISES...AND WHEN COMBINED WITH WARM ADVECTION WITHIN BACKING LOW LEVEL FLOW...LOW TEMPERATURES IN THE UPPER 30S INLAND TO LOW 40S NEAR THE COAST WILL ALSO BE SEVERAL DEGREES WARMER THAN AVERAGE. MONDAY...SOUTHERN STREAM SHORTWAVE ENERGY TRACKING ACROSS THE GULF OF MEXICO WILL SPIN UP A SURFACE WAVE ALONG THE WESTERN PERIPHERY OF THE RETREATING ATLANTIC HIGH PRESSURE. THERE REMAINS NOTABLE DISAGREEMENT BETWEEN MODEL SOLUTIONS REGARDING THE STRENGTH AND TRACK OF THIS LOW PRESSURE WAVE AND TRAILING FRONT AS THEY PROGRESS TOWARD THE FORECAST AREA THROUGH THE DAY. IN GENERAL...A SOLID TAP INTO GULF MOISTURE WILL SUPPORT A SWATH OF PRECIPITATION ASSOCIATED WITH THE SYSTEM...AND EXPECT RAIN CHANCES TO INCREASE FROM SOUTHWEST TO NORTHEAST DURING THE LATE AFTERNOON TO EVENING TIME FRAME. WARM ADVECTION AND PRE-FRONTAL COMPRESSION WILL SUPPORT TEMPERATURES PEAKING IN THE MID TO UPPER 60S...EVEN AS CLOUD COVER GRADUALLY INCREASES. THE BEST RAIN POTENTIAL ACTUALLY APPEARS TO OCCUR OVERNIGHT INTO EARLY TUESDAY MORNING..AS THE SURFACE LOW LIFTS NORTH/NORTHEAST AND PULLS THE FRONT INTO THE REGION. LOW TEMPERATURES WILL BE QUITE MILD AS A RESULT...ONLY FALLING INTO THE UPPER 40S TO AROUND 50 DEGREES. TUESDAY...THE SYNOPTIC PATTERN REMAINS A BIT UNSETTLED EVEN AFTER THE FRONT MOVES OFFSHORE...WITH ANOTHER LARGE AREA OF UPPER LEVEL ENERGY SWEEPING SOUTHEAST FROM THE GREAT LAKES REGION. RAIN CHANCES WILL DECREASE DURING THE MORNING HOURS BEHIND THE DEPARTING COLD FRONT. HOWEVER DRY SURFACE HIGH PRESSURE IN ITS WAKE WILL BECOME SUPPRESSED TO THE SOUTH...AS YET ANOTHER FRONT DRIVEN BY THE AMPLIFYING UPPER SHORTWAVE DESCENDS FROM THE OHIO VALLEY LATE IN THE DAY. ONCE AGAIN...DOWNSLOPE FLOW AND THE LACK OF SOLID COLD ADVECTION WILL SUPPORT ABOVE NORMAL HIGH TEMPERATURES IN THE MID 60S. && .LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/... THE DEEPENING UPPER TROUGH WILL SHIFT OVER THE EAST COAST STATES ON WEDNESDAY...WITH A DRY COLD FRONT MOVING ACROSS THE REGION EARLY IN THE DAY. THERE APPEARS TO BE MORE NOTABLE COLD ADVECTION BEHIND THIS FRONT...AND EXPECT HIGH TEMPERATURES TO BE SUPPRESSED IN THE MID 50S UNDER MOSTLY CLEAR SKIES ON WEDNESDAY. LOW TEMPERATURES WEDNESDAY NIGHT WILL BE THE COLDEST SEEN IN DAYS...AS LIGHT WINDS AND LITTLE TO NO CLOUD COVER SET UP IDEAL RADIATIONAL COOLING CONDITIONS. A NEARLY ZONAL UPPER PATTERN ON THURSDAY WILL BE RATHER TRANSIENT...AS BROAD TROUGHING BECOMES THE DOMINANT FEATURE ALOFT FRIDAY AND SATURDAY. CONSIDERING DRY SURFACE HIGH PRESSURE WILL ALSO SETTLE OVER THE REGION...EXPECT TEMPERATURES TO BE GENERALLY BELOW NORMAL AND RAIN CHANCES TO REMAIN BELOW 15 PERCENT THROUGH THE EXTENDED FORECAST PERIOD. && .AVIATION /12Z SATURDAY THROUGH WEDNESDAY/... FOG IS IN THE PROCESS OF LIFTING INTO VERY LOW STRATUS DECKS AT BOTH TERMINALS AS BOUNDARY LAYER WINDS INCREASE. LIFR CIGS WILL LINGER THROUGH ABOUT 14Z BEFORE SLOWLY RISING. UNTIL THEN...CIGS WILL REMAIN VERY NEAR AIRFIELD MINIMUMS AND WELL BELOW ALTERNATE MINIMUMS. VFR SHOULD RETURN BY LATE MORNING. SQUALL LINE WILL AFFECT THE TERMINALS THIS AFTERNOON...ROUGHLY FROM 20-23Z. WILL INCLUDE LOW-END MVFR CONDITIONS IN TSRA FOR NOW...BUT BRIEF STINTS AS LOW AS LIFR WILL BE POSSIBLE IN HEAVIER POCKETS OF RAIN. THE FRONT WILL CLEAR THE TERMINALS THIS EVENING...ROUGHLY 00-23Z WITH VFR CONDITIONS RETURNING THROUGH THE NIGHT AS CLEARING TAKES HOLD. EXTENDED AVIATION OUTLOOK...THERE IS A CHANCE OF SHOWERS/MVFR CONDITIONS LATE MONDAY INTO EARLY TUESDAY DUE TO ANOTHER FRONTAL SYSTEM. && .MARINE... SATELLITE AND GOES LIFR PROBABILITIES SUGGEST SEA FOG HAS MOVED INTO THE GEORGIA OFFSHORE WATERS. HAVE EXPANDED THE MARINE DENSE FOG ADVISORY TO INCLUDE THIS AREA THROUGH 10 PM. TODAY...THE RISK FOR WIDESPREAD DENSE SEA FOG WILL LINGER THROUGH MUCH OF THE MORNING HOURS AND MAY PERSIST INTO THE AFTERNOON HOURS AS WARM/MOIST AIR FLOWS OVER THE COLD SHELF WATERS. A MARINE DENSE FOG ADVISORY WILL REMAIN IN FORCE UNTIL 10 AM FOR ALL FORECAST ZONES...BUT MAY NEED TO BE EXTENDED INTO THE AFTERNOON HOURS DEPENDING ON TRENDS AND PILOT BOAT REPORTS LATER THIS MORNING. OTHERWISE...SOUTH WINDS WILL INCREASE TODAY AS A COLD FRONT DRAWS CLOSER. EXPECT WINDS TO INCREASE TO 15-20 KT NEARSHORE WATERS AND 20-25 KT OFFSHORE WATERS. SEAS WILL BUILD AS A RESULT...RISING TO 4-7 FT NEARSHORE WATERS AND 6-8 FT OFFSHORE WATERS. A LINE OF STRONG TO SEVERE TSTMS WILL LIKELY APPROACH THE LOCAL MARINE AREA LATE IN THE AFTERNOON...ALTHOUGH A FEW STRONG SHOWERS/TSTMS MAY POP OVER THE COASTAL WATERS PRIOR TO ARRIVAL OF THE PRIMARY CONVECTIVE LINE. SPECIAL MARINE WARNINGS MAY BE NEEDED. TONIGHT...THE SQUALL LINE WILL PUSH ACROSS THE WATERS THIS EVENING AND BE FOLLOWED BY THE COLD FRONT. WINDS WILL QUICKLY SHIFT WEST WITH THE FRONT AND INCREASE WITH THE ONSET OF COLD AIR ADVECTION. WINDS LOOK TO PEAK 20-25 KT NEARSHORE WATERS AND 25-30 KT OFFSHORE WATERS. RIGHT NOW WINDS LOOK TO REMAIN BELOW GALE FORCE...ALTHOUGH A BRIEF STINT OF 35 KT WINDS WILL BE POSSIBLE. WILL MAINTAIN SMALL CRAFT ADVISORIES FOR ALL WATERS...EXCLUDING THE CHARLESTON HARBOR. OFFSHORE WINDS WILL HAVE A DECAYING EFFECT OF SEAS OVER THE NEARSHORE WATERS WITH SEAS SUBSIDING BY ABOUT 1-2 FT...BUT SEAS OF 6-8 FT WILL LINGER OVER THE OFFSHORE WATERS WHERE THE FETCH WILL BE CONSIDERABLY LONGER. SUNDAY THROUGH WEDNESDAY...LINGERING SMALL CRAFT ADVISORIES WILL BE ABLE TO END BY SUNDAY MORNING/EARLY AFTERNOON...AS SURFACE HIGH PRESSURE RAPIDLY BUILDS OVER THE REGION IN THE WAKE OF THE COLD FRONT. MARINE CONDITIONS WILL THEN REMAIN RATHER QUIET THROUGH THE DAYTIME HOURS ON MONDAY. A WAVE OF LOW PRESSURE IN THE GULF OF MEXICO WILL LIFT TOWARD THE SOUTHEAST STATES LATE MONDAY...LIKELY PULLING A COLD FRONT OFF THE COAST BY TUESDAY MORNING. EXPECT A SURGE IN SOUTHERLY WINDS AHEAD OF THE SYSTEM EARLY TUESDAY...WITH THE POTENTIAL FOR ONLY MARGINAL ADVISORY-LEVEL WINDS ACROSS PORTIONS OF THE WATERS. A MORE SOLID SURGE INTO SMALL CRAFT ADVISORY CONDITIONS WILL OCCUR WITHIN COLD ADVECTION AND WESTERLY FLOW BEHIND A SECONDARY COLD FRONT MOVING THROUGH THE AREA EARLY WEDNESDAY. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...DENSE FOG ADVISORY UNTIL 10 AM EST THIS MORNING FOR GAZ117-119- 139-141. SC...DENSE FOG ADVISORY UNTIL 10 AM EST THIS MORNING FOR SCZ048>052. MARINE...DENSE FOG ADVISORY UNTIL 10 AM EST THIS MORNING FOR AMZ330-350- 352-354-374. SMALL CRAFT ADVISORY UNTIL 5 AM EST SUNDAY FOR AMZ352-354. SMALL CRAFT ADVISORY UNTIL 8 AM EST SUNDAY FOR AMZ350. SMALL CRAFT ADVISORY UNTIL 1 PM EST SUNDAY FOR AMZ374. && $$ ST/WMS
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
621 AM EST SAT JAN 11 2014 ...SEVERE THUNDERSTORMS POSSIBLE THIS AFTERNOON AND EVENING... .SYNOPSIS... A STRONG COLD FRONT WILL SWEEP ACROSS THE REGION THIS EVENING. HIGH PRESSURE WILL BUILD SUNDAY AND QUICKLY MOVE OFF THE COAST MONDAY...BEFORE ANOTHER COLD FRONT MOVES THROUGH THE AREA BY TUESDAY MORNING. HIGH PRESSURE WILL REBUILD DURING THE MIDDLE OF NEXT WEEK...WITH YET ANOTHER COLD FRONT APPROACHING BY FRIDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... VSBYS HAVE IMPROVED ACROSS INLAND JASPER AND INLAND CHATHAM COUNTIES. THE DENSE FOG ADVISORY HAS BEEN CANCELLED FOR THESE TWO ZONES. THE ADVISORY REMAINS IN EFFECT FOR ALL COASTAL ZONES...INCLUDING TIDAL BERKELEY UNTIL 10 AM. 1 PM TO 7 PM TIMING FOR SEVERE TSTMS STILL LOOKS ON TRACK PER H3R OUTPUT. TODAY...AN ACTIVE DAY IS ON TAP FOR SOUTHEAST SOUTH CAROLINA AND SOUTHEAST GEORGIA AS A COLD FRONT APPROACHES FROM THE WEST. AHEAD OF THE FRONT...INCREASING WARM AIR ADVECTION BEING DRIVEN BY A STRONG PRE-FRONTAL LOW-LEVEL JET WILL HELP PUSH TEMPERATURES INTO THE LOWER-MID 70S FOR MOST AREAS AWAY FROM THE COAST... WHICH IS ABOUT 10-15 DEGREES ABOVE NORMAL. AS WARM AIR ADVECTION INTENSIFIES...ISOLATED TO SCATTERED SHOWERS WILL LIKELY BREAKOUT AND AFFECT PORTIONS OF THE AREA PRIOR TO THE ARRIVAL OF THE MAIN CONVECTIVE LINE. ATTM IT APPEARS THE MAIN CONVECTIVE LINE... POSSIBLY IN THE FORM OF A STRONG/SEVERE QUASI-LINEAR CONVECTIVE SYSTEM /QLCS/...WILL REACH THE FAR WESTERN ZONES BY EARLY AFTERNOON AND REACH THE COAST BY LATE AFTERNOON OR EARLY THIS EVENING. H3R INSTABILITY PROGS AND NAM/RAP MODIFIED POINT SOUNDINGS SUGGEST SBCAPE VALUES WILL RISE TO 900-1200 J/KG WITH LIFTED INDICES DROPPING AS LOW AS -4 TO -6C. ALTHOUGH MID-LEVEL LAPSE RATES WILL BE POOR...HEALTHY 0-6KM BULK SHEAR OF 50-60 KT INDUCED BY STRONG LOW-LEVEL JETTING COUPLED WITH MODEST INSTABILITY WILL SUPPORT A RISK FOR SEVERE TSTMS WITHIN A TYPICAL MID-JANUARY HIGH SHEAR/LOW CAPE ENVIRONMENT. THE PRIMARY HAZARD RIGHT NOW LOOK TO BE DAMAGING WINDS WITH A RISK FOR ISOLATED TORNADOES WHERE DISCRETE CELLS OR EMBEDDED MESO-VORTICES WITHIN BOWING CONVECTIVE LINE SEGMENTS CAN DEVELOP. RAP 0-1KM HELICITY VALUES INCREASE TO NEAR 300 M2/S2 AND THE HIGH SHEAR/LOW CAPE SHERBS3 TORNADO PARAMETER RISES ABOVE THE BENCH MARK OF 1 UNIT FOR MUCH OF THE AREA...ALL SUGGESTING THERE IS A REASONABLE RISK FOR TORNADOES. FOR TODAY...WILL HIGHLIGHT POPS NEAR 100 PERCENT FOR ALL AREAS WITH THE HIGHEST GRIDDED POPS PLACED WITH THE EXPECTED TIMING/PLACEMENT OF THE EXPECTED CONVECTIVE LINE. HIGHS WILL BE IN THE LOWER TO MID 70S UNDER MAINLY CLOUDY SKIES. WILL INCLUDE DAMAGING WIND AND TORNADO ATTRIBUTES IN ALL GRIDDED AND TEXT PRODUCTS AND HIGHLIGHT A POTENTIAL FOR SEVERE TSTMS IN THE HAZARDOUS WEATHER OUTLOOK. THE WINDOW OF GREATEST SEVERE THREAT LOOKS TO BE 1 PM THROUGH 7 PM. && .SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/... TONIGHT...CONDITIONS WILL RAPIDLY IMPROVE THIS EVENING AS THE PRIMARY CONVECTIVE LINE PUSHES OFFSHORE AND THE COLD FRONT MOVES THROUGH. EXPECT CLEARING TO OCCUR DURING THE EVENING HOURS WITH MAINLY CLEAR SKIES DEVELOPING BY MIDNIGHT...IF NOT SOONER. LOWS WILL RANGE FROM THE LOWER 40S WELL INLAND TO THE UPPER 40S AT THE BEACHES. SUNDAY...DRY HIGH PRESSURE WILL BUILD IN THE WAKE OF THE DEPARTING COLD FRONT...YET PROGRESSIVE FLOW ALOFT WILL PULL THE CENTER OF THE HIGH QUICKLY TOWARD THE NEARBY ATLANTIC WATERS. COLD ADVECTION WILL BE WEAK BEHIND THE FRONT...AND WITH WIND DIRECTIONS REMAINING GENERALLY WEST/SOUTHWEST...EXPECT ONLY A SLIGHT COOLING TREND TO OCCUR. HIGH TEMPERATURES IN THE MID TO UPPER 60S WILL BE COOLER THAN THE PREVIOUS DAY...YET STILL BE WELL ABOVE SEASONAL NORMALS. AN AMPLIFYING LONG WAVE TROUGH ACROSS THE CENTRAL PLAINS AFTER MIDNIGHT WILL SUPPORT BRIEF DOWNSTREAM HEIGHT RISES...AND WHEN COMBINED WITH WARM ADVECTION WITHIN BACKING LOW LEVEL FLOW...LOW TEMPERATURES IN THE UPPER 30S INLAND TO LOW 40S NEAR THE COAST WILL ALSO BE SEVERAL DEGREES WARMER THAN AVERAGE. MONDAY...SOUTHERN STREAM SHORTWAVE ENERGY TRACKING ACROSS THE GULF OF MEXICO WILL SPIN UP A SURFACE WAVE ALONG THE WESTERN PERIPHERY OF THE RETREATING ATLANTIC HIGH PRESSURE. THERE REMAINS NOTABLE DISAGREEMENT BETWEEN MODEL SOLUTIONS REGARDING THE STRENGTH AND TRACK OF THIS LOW PRESSURE WAVE AND TRAILING FRONT AS THEY PROGRESS TOWARD THE FORECAST AREA THROUGH THE DAY. IN GENERAL...A SOLID TAP INTO GULF MOISTURE WILL SUPPORT A SWATH OF PRECIPITATION ASSOCIATED WITH THE SYSTEM...AND EXPECT RAIN CHANCES TO INCREASE FROM SOUTHWEST TO NORTHEAST DURING THE LATE AFTERNOON TO EVENING TIME FRAME. WARM ADVECTION AND PRE-FRONTAL COMPRESSION WILL SUPPORT TEMPERATURES PEAKING IN THE MID TO UPPER 60S...EVEN AS CLOUD COVER GRADUALLY INCREASES. THE BEST RAIN POTENTIAL ACTUALLY APPEARS TO OCCUR OVERNIGHT INTO EARLY TUESDAY MORNING..AS THE SURFACE LOW LIFTS NORTH/NORTHEAST AND PULLS THE FRONT INTO THE REGION. LOW TEMPERATURES WILL BE QUITE MILD AS A RESULT...ONLY FALLING INTO THE UPPER 40S TO AROUND 50 DEGREES. TUESDAY...THE SYNOPTIC PATTERN REMAINS A BIT UNSETTLED EVEN AFTER THE FRONT MOVES OFFSHORE...WITH ANOTHER LARGE AREA OF UPPER LEVEL ENERGY SWEEPING SOUTHEAST FROM THE GREAT LAKES REGION. RAIN CHANCES WILL DECREASE DURING THE MORNING HOURS BEHIND THE DEPARTING COLD FRONT. HOWEVER DRY SURFACE HIGH PRESSURE IN ITS WAKE WILL BECOME SUPPRESSED TO THE SOUTH...AS YET ANOTHER FRONT DRIVEN BY THE AMPLIFYING UPPER SHORTWAVE DESCENDS FROM THE OHIO VALLEY LATE IN THE DAY. ONCE AGAIN...DOWNSLOPE FLOW AND THE LACK OF SOLID COLD ADVECTION WILL SUPPORT ABOVE NORMAL HIGH TEMPERATURES IN THE MID 60S. && .LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/... THE DEEPENING UPPER TROUGH WILL SHIFT OVER THE EAST COAST STATES ON WEDNESDAY...WITH A DRY COLD FRONT MOVING ACROSS THE REGION EARLY IN THE DAY. THERE APPEARS TO BE MORE NOTABLE COLD ADVECTION BEHIND THIS FRONT...AND EXPECT HIGH TEMPERATURES TO BE SUPPRESSED IN THE MID 50S UNDER MOSTLY CLEAR SKIES ON WEDNESDAY. LOW TEMPERATURES WEDNESDAY NIGHT WILL BE THE COLDEST SEEN IN DAYS...AS LIGHT WINDS AND LITTLE TO NO CLOUD COVER SET UP IDEAL RADIATIONAL COOLING CONDITIONS. A NEARLY ZONAL UPPER PATTERN ON THURSDAY WILL BE RATHER TRANSIENT...AS BROAD TROUGHING BECOMES THE DOMINANT FEATURE ALOFT FRIDAY AND SATURDAY. CONSIDERING DRY SURFACE HIGH PRESSURE WILL ALSO SETTLE OVER THE REGION...EXPECT TEMPERATURES TO BE GENERALLY BELOW NORMAL AND RAIN CHANCES TO REMAIN BELOW 15 PERCENT THROUGH THE EXTENDED FORECAST PERIOD. && .AVIATION /11Z SATURDAY THROUGH WEDNESDAY/... FOG IS IN THE PROCESS OF LIFTING INTO VERY LOW STRATUS DECKS AT BOTH TERMINALS AS BOUNDARY LAYER WINDS INCREASE. LIFR CIGS WILL LINGER THROUGH ABOUT 14Z BEFORE SLOWLY RISING. UNTIL THEN...CIGS WILL REMAIN VERY NEAR AIRFIELD MINIMUMS AND WELL BELOW ALTERNATE MINIMUMS. VFR SHOULD RETURN BY LATE MORNING. SQUALL LINE WILL AFFECT THE TERMINALS THIS AFTERNOON...ROUGHLY FROM 20-23Z. WILL INCLUDE LOW-END MVFR CONDITIONS IN TSRA FOR NOW...BUT BRIEF STINTS AS LOW AS LIFR WILL BE POSSIBLE IN HEAVIER POCKETS OF RAIN. THE FRONT WILL CLEAR THE TERMINALS THIS EVENING...ROUGHLY 00-23Z WITH VFR CONDITIONS RETURNING THROUGH THE NIGHT AS CLEARING TAKES HOLD. EXTENDED AVIATION OUTLOOK...THERE IS A CHANCE OF SHOWERS/MVFR CONDITIONS LATE MONDAY INTO EARLY TUESDAY DUE TO ANOTHER FRONTAL SYSTEM. && .MARINE... TODAY...THE RISK FOR WIDESPREAD DENSE SEA FOG WILL LINGER THROUGH MUCH OF THE MORNING HOURS AND MAY PERSIST INTO THE AFTERNOON HOURS AS WARM/MOIST AIR FLOWS OVER THE COLD SHELF WATERS. A MARINE DENSE FOG ADVISORY WILL REMAIN IN FORCE UNTIL 10 AM FOR ALL FORECAST ZONES...BUT MAY NEED TO BE EXTENDED INTO THE AFTERNOON HOURS DEPENDING ON TRENDS AND PILOT BOAT REPORTS LATER THIS MORNING. OTHERWISE...SOUTH WINDS WILL INCREASE TODAY AS A COLD FRONT DRAWS CLOSER. EXPECT WINDS TO INCREASE TO 15-20 KT NEARSHORE WATERS AND 20-25 KT OFFSHORE WATERS. SEAS WILL BUILD AS A RESULT...RISING TO 4-7 FT NEARSHORE WATERS AND 6-8 FT OFFSHORE WATERS. A LINE OF STRONG TO SEVERE TSTMS WILL LIKELY APPROACH THE LOCAL MARINE AREA LATE IN THE AFTERNOON...ALTHOUGH A FEW STRONG SHOWERS/TSTMS MAY POP OVER THE COASTAL WATERS PRIOR TO ARRIVAL OF THE PRIMARY CONVECTIVE LINE. SPECIAL MARINE WARNINGS MAY BE NEEDED. TONIGHT...THE SQUALL LINE WILL PUSH ACROSS THE WATERS THIS EVENING AND BE FOLLOWED BY THE COLD FRONT. WINDS WILL QUICKLY SHIFT WEST WITH THE FRONT AND INCREASE WITH THE ONSET OF COLD AIR ADVECTION. WINDS LOOK TO PEAK 20-25 KT NEARSHORE WATERS AND 25-30 KT OFFSHORE WATERS. RIGHT NOW WINDS LOOK TO REMAIN BELOW GALE FORCE...ALTHOUGH A BRIEF STINT OF 35 KT WINDS WILL BE POSSIBLE. WILL MAINTAIN SMALL CRAFT ADVISORIES FOR ALL WATERS...EXCLUDING THE CHARLESTON HARBOR. OFFSHORE WINDS WILL HAVE A DECAYING EFFECT OF SEAS OVER THE NEARSHORE WATERS WITH SEAS SUBSIDING BY ABOUT 1-2 FT...BUT SEAS OF 6-8 FT WILL LINGER OVER THE OFFSHORE WATERS WHERE THE FETCH WILL BE CONSIDERABLY LONGER. SUNDAY THROUGH WEDNESDAY...LINGERING SMALL CRAFT ADVISORIES WILL BE ABLE TO END BY SUNDAY MORNING/EARLY AFTERNOON...AS SURFACE HIGH PRESSURE RAPIDLY BUILDS OVER THE REGION IN THE WAKE OF THE COLD FRONT. MARINE CONDITIONS WILL THEN REMAIN RATHER QUIET THROUGH THE DAYTIME HOURS ON MONDAY. A WAVE OF LOW PRESSURE IN THE GULF OF MEXICO WILL LIFT TOWARD THE SOUTHEAST STATES LATE MONDAY...LIKELY PULLING A COLD FRONT OFF THE COAST BY TUESDAY MORNING. EXPECT A SURGE IN SOUTHERLY WINDS AHEAD OF THE SYSTEM EARLY TUESDAY...WITH THE POTENTIAL FOR ONLY MARGINAL ADVISORY-LEVEL WINDS ACROSS PORTIONS OF THE WATERS. A MORE SOLID SURGE INTO SMALL CRAFT ADVISORY CONDITIONS WILL OCCUR WITHIN COLD ADVECTION AND WESTERLY FLOW BEHIND A SECONDARY COLD FRONT MOVING THROUGH THE AREA EARLY WEDNESDAY. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...DENSE FOG ADVISORY UNTIL 10 AM EST THIS MORNING FOR GAZ117-119- 139-141. SC...DENSE FOG ADVISORY UNTIL 10 AM EST THIS MORNING FOR SCZ048>052. MARINE...DENSE FOG ADVISORY UNTIL 10 AM EST THIS MORNING FOR AMZ330-350- 352-354. SMALL CRAFT ADVISORY FROM 10 AM THIS MORNING TO 5 AM EST SUNDAY FOR AMZ352-354. SMALL CRAFT ADVISORY UNTIL 8 AM EST SUNDAY FOR AMZ350. SMALL CRAFT ADVISORY UNTIL 1 PM EST SUNDAY FOR AMZ374. && $$ ST/WMS
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
329 AM CST SAT JAN 11 2014 .DISCUSSION... 857 PM CST REGIONAL SATELLITE IMAGERY SHOWS A PRONOUNCED MID LEVEL DRY SLOT PUNCHING IN ACROSS EASTERN IOWA AND FAR NORTHWESTERN ILLINOIS THIS EVENING. THIS FEATURE SHOULD CONTINUE EASTWARD ACROSS NORTHERN ILLINOIS OVERNIGHT...AND THIS WILL MARK AN END TO THE MUCH OF THE RAIN AND A TRANSITION TO DRIZZLE AND FOG ACROSS MUCH OF THE AREA AFTER MIDNIGHT. I WILL CONTINUE THE CURRENT FREEZING RAIN HEADLINE AS IS FOR NOW...DUE TO ALL THE REPORTS OF ICING AND BAD TRAVEL CONDITIONS ON AREA ROADS AND SIDE WALKS. WITH TIME...TEMPERATURES AND DEW POINTS IN THE MID TO UPPER 30S SHOULD SLOWLY WARM THE GROUND ENOUGH TO LIMIT ICING OVERNIGHT...BUT BY THIS TIME MOST OF THE PRECIP SHOULD BE DONE ANYWAYS. THE OTHER CONCERN WE ARE WATCHING OVER THE NEXT FEW HOURS IS THAT OF DENSE FOG. SEVERAL SITES ACROSS EASTERN IOWA AND INTO NORTHWESTERN ILLINOIS ARE REPORTING VISIBILITIES DROPPING DOWN AROUND A QUARTER MILE IN FOG. IT APPEARS THE MAIN THREAT FOR DENSE FOG WILL FOLLOW CLOSELY WITH THE TRACK OF THE SURFACE LOW...WHICH IS EXPECTED TO PUSH RIGHT ACROSS NORTHWESTERN ILLINOIS AND SOUTHERN WISCONSIN TONIGHT. SOME OF THIS DENSER FOG COULD GET INTO MY WESTERN AREAS. HOWEVER...I AM A LITTLE RELUCTANT TO ISSUE A DENSE FOG ADVISORY FOR THESE AREAS AS IT APPEARS THE DENSER FOG MAY BE SHORT LIVED...ONLY LASTING A COUPLE HOURS...WITH CONDITIONS IMPROVING RAPIDLY WITH THE PASSAGE OF THE SURFACE LOW AND COLD FRONT. I WILL CONTINUE TO MONITOR THE TRENDS...AND I MAY JUST COVER WITH AN SPS UNLESS IT BECOMES CLEAR THAT THE FOG COULD LAST A BIT LONGER. KJB //PREV DISCUSSION... 624 PM CST WE DECIDED TO ISSUE A FREEZING RAIN ADVISORY THROUGH THIS EVENING. ALTHOUGH AIR TEMPERATURES CONTINUE TO WARM TO NEAR 40...THE COLD GROUND IS ALLOWING AREA ROADS TO BECOME ICY. WE RECEIVED NUMEROUS REPORTS OF ACCIDENTS AND EVEN CLOSED HIGHWAYS ACROSS NORTH CENTRAL ILLINOIS. THE ILLINOIS STATE POLICE IS URGING DRIVERS TO STAY HOME THIS EVENING ACROSS NORTH CENTRAL ILLINOIS. GIVEN HOW BAD CONDITIONS APPEAR TO BE...WE HAVE OPTED TO GO WITH A FREEZING RAIN ADVISORY IN SPITE OF CONTINUED WARMING. WITH TIME THE ROAD TEMPS SHOULD WARM AND END THE THREAT FOR ICING. KJB && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 09Z... * IFR OR LOWER CIGS AND OCCASIONALLY VSBY UNTIL SUNRISE * VSBY RETURNS TO VFR AFTER SUNRISE SHORTLY AFTER WIND SHIFT TO WEST * IFR CIGS LIKELY TO PERSIST THROUGH MID MORNING WITH POSSIBLE IMPROVEMENT TO MVFR THIS AFTERNOON IZZI //DISCUSSION...UPDATED 09Z... HIGHLY VARIABLE VSBY IN THE WARM SECTOR AHEAD OF THE COLD FRONT WITH SOME LOCATIONS DOWN TO 1/4SM AND OTHERS STILL VFR...INCLUDING ORD/MDW. STILL FEEL THERE IS A GOOD SHOT AT ORD/MDW AT LEAST TEMPORARILY SEEING RATHER DENSE FOG DEVELOP FOR A TIME PRIOR TO WIND SHIFT TO THE WEST JUST BEFORE SUNRISE. REST OF TRENDS FROM PREVIOUS TAF LOOK GOOD. IZZI UPDATED 06Z... AREAS OF RAIN WILL CONTINUE TO AFFECT THE CHGO METRO TERMINALS THRU EARLY PART OF THE OVERNIGHT HOURS. IFR/LIFR CIGS WILL PERSIST IN THE MOIST SOUTHERLY WINDS TONIGHT IN ADVANCE OF APPROACHING COLD FRONT WITH AREAS OF IFR VSBY EXPECTED THROUGH REST OF THE OVERNIGHT HOURS. COLD FRONT SHOULD MOVE THROUGH RFD AROUND 09Z AND THROUGH CHGO METRO AROUND 11Z WITH WIND SHIFT TO WEST AND A SLOW FILTERING IN OF SLIGHTLY DRIER CONDITIONS RESULTING IN IMPROVING VSBY EARLY SATURDAY MORNING. STRATUS (MOSTLY IFR) EXTENDS BACK ACROSS ALL OF IOWA AND IS UNLIKELY TO MIX OUT SATURDAY...SO WOULD ANTICIPATE LOW CIGS TO HANG AROUND INTO SATURDAY AFTERNOON AND POSSIBLY INTO EVENING. SOME IMPROVEMENT TO LOW END MVFR IS POSSIBLE SATURDAY AFTERNOON. IZZI //ORD AND MDW CONFIDENCE...UPDATED 09Z... * HIGH CONFIDENCE IN IFR CIGS THROUGH AT LEAST MID MORNING * LOW-MEDIUM CONFIDENCE IN IMPROVEMENT TO MVFR TODAY * NO CONFIDENCE IN CIG FORECAST THIS EVENING * LOW CONFIDENCE THROUGH SUNRISE...HIGH CONFIDENCE IN VSBY REST OF TODAY * HIGH CONFIDENCE IN WIND FORECAST IZZI //OUTLOOK FOR ORD/MDW FOR 12Z SUNDAY-12Z FRIDAY...UPDATED 00Z... SUNDAY...STRONG SOUTH WINDS...LLWS POSSIBLE AFTERNOON/EARLY EVENING. VFR PROBABLE. MONDAY...VFR. TUESDAY...CHANCE OF SNOW/IFR. WEDNESDAY AND THURSDAY...VFR PROBABLE. MDB && .MARINE... 155 AM CST APPEARS AS THOUGH WE WILL ENTER ANOTHER BUSY PERIOD ON LAKE MICHIGAN WITH SEVERAL BOUTS OF GALES EXPECTED OVER THE NEXT WEEK AND ONLY BRIEF TIME WINDOWS OF LIGHTER WINDS. A MODERATELY STRONG WEST WIND WILL DEVELOP TODAY IN THE WAKE OF LOW PRESSURE DEPARTING THE REGION WITH A BRIEF LULL IN THE WINDS LATE TONIGHT INTO EARLY SUNDAY MORNING AS THEY BACK TO SOUTHWEST. AN INTENSE AND FAST MOVING LOW WILL RACE EAST ACROSS CANADA SUNDAY RESULTING IN A PERIOD OF SOUTH GALES...PROBABLY HIGHER END GALES OVER NORTHERN PORTIONS OF THE LAKE SUNDAY AFTERNOON AND EVENING. WHILE WINDS SHOULD EASE BELOW GALE FORCE BY MONDAY MORNING THEY SHOULD REMAIN FAIRLY STRONG THROUGH THE DAY MONDAY. TRACK/TIMING DIFFERENCES EXIST REGARDING A FAIRLY STRONG CLIPPER RACING SOUTHEAST INTO THE MIDWEST TUESDAY WITH ANOTHER PERIOD OF STRONG NORTHERLY WINDS AND POSSIBLE GALES IN THE WAKE OF THAT SYSTEM LATE TUESDAY OR EARLY WEDNESDAY. YET ANOTHER PERIOD OF GALES LOOKS LIKE A GOOD BET BY THURSDAY. IZZI && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...GALE WATCH...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565- LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868- LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...11 AM SUNDAY TO 3 AM 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 National Weather Service Lincoln IL 242 AM CST Sat Jan 11 2014 .DISCUSSION... ISSUED 240 AM CST Sat Jan 11 2014 Area of dense fog has been rolling eastward across the state early this morning ahead of a cold front, which was just crossing the Illinois/Iowa border at 2 am. The back edge of the fog is about 50-75 miles east of the front, so am most concerned east of the Illinois River for the next few hours. The lingering rain was mainly along the Indiana border and should be out of the forecast area soon. Temperatures have remained quite mild overnight, with upper 30s and lower 40s in many areas except the far northwest. Main forecast concerns involve precipitation chances next week, with periodic clipper systems zipping southeast. Also have some concerns with the extent of cold air late next week, with discrepancies between the GFS and ECMWF models on how far south the cold air will surge. SHORT TERM...Today through Monday: Will drop the dense fog advisory west of the Illinois River. HRRR has been doing a reasonable job with the low visibilities, and the threat will be more across the east. Will expand the advisory to cover the remainder of the CWA east of I-57 for a few hours early this morning, and extend the time a bit to around 7 am. Much of the fog should be out of the area by that point, except perhaps around Champaign and Danville. Deep upper trough to quickly swing eastward today, followed by another broadening trough early next week. Southerly winds to 25-30 mph and decent sunshine should boost temperatures into the mid-upper 40s everywhere, with some lower 50s in the southwest and southeast corners of the CWA. Cooler conditions on Monday as a cold front passes with the trough. Surge of moisture pushing northeast from the lower Mississippi Valley ahead of the trough has trended a bit further east with the latest model runs, and associated rainfall may largely miss us. Have maintained some 30-40% PoP`s mainly in the morning across the eastern CWA, but would not be surprised to see those continue to lower with subsequent forecasts. LONG TERM...Tuesday through Friday: Active upper pattern on tap for the upcoming week, with concerns for light precipitation and surge of cold air. Regarding the precipitation, first clipper will be racing southeast Monday night. The GFS is much more progressive and keeps the precip to the north, while the ECMWF and GEM models favor a more southern track and somewhat higher chances of precip. Have raised PoP`s a bit from the initialization levels to favor these latter models, and will mention a chance of snow on Tuesday, with a mix in the afternoon in the central and south. Second and stronger system will track more across the northern Great Lakes region and have kept precip chances out of our area, but Thursday and Thursday night will be rather windy. Latest ECMWF continues its trend of plunging a lobe of cold air much further south than the GFS late in the week, as the former model digs the eastern U.S. trough much deeper. 850 mb temps of -18C on the ECMWF would favor some teens for highs by Friday, while the GFS`s trough is already well to our east. Have not gone as cold as the ECMWF, but will continue with highs below freezing in all areas on Friday. Geelhart && .AVIATION... ISSUED 1147 PM CST Fri Jan 10 2014 The cold front is just arriving in far western IL as of 05z, and will progress eastward across the terminal sites over the next 5-6 hours. Dense fog has begun to expand eastward with BMI and CMI down to 1/4SM FG. HRRR and RAP hi-res models still show widespread coverage of dense fog across a majority of central IL overnight, gradually clearing from the west late, with PIA vis improving to vfr after 11z. Have gone more pessimistic with vis across the board through sunrise, with the VLIFR mainly across the north. SPI and DEC have dodged the dense fog so far, but can not rule out a brief period of FG the rest of the night. Dense fog may linger at CMI to 13z, then clear out to VFR quickly. Clouds will remain in the IFR/LIFR range through much of the morning. Some VLIFR may continue at BMI until after sunrise as well. Clouds should improve to MVFR Sat afternoon, with a clearing line expected to push across the area by Sat evening. Winds will shift from S-SW to W with the cold FROPA, with winds shifting at PIA around 07-08z, and at CMI toward 12z. Wind speeds should remain steady in the 09-13kt range overnight, with gusts to 22-24kt returning Sat morning as mixing deepens. Shimon && .ILX WATCHES/WARNINGS/ADVISORIES... DENSE FOG ADVISORY until 7 AM CST this morning for ILZ031-037-038-045-046-055>057-062-063-066>073. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
155 AM CST SAT JAN 11 2014 .DISCUSSION... 857 PM CST REGIONAL SATELLITE IMAGERY SHOWS A PRONOUNCED MID LEVEL DRY SLOT PUNCHING IN ACROSS EASTERN IOWA AND FAR NORTHWESTERN ILLINOIS THIS EVENING. THIS FEATURE SHOULD CONTINUE EASTWARD ACROSS NORTHERN ILLINOIS OVERNIGHT...AND THIS WILL MARK AN END TO THE MUCH OF THE RAIN AND A TRANSITION TO DRIZZLE AND FOG ACROSS MUCH OF THE AREA AFTER MIDNIGHT. I WILL CONTINUE THE CURRENT FREEZING RAIN HEADLINE AS IS FOR NOW...DUE TO ALL THE REPORTS OF ICING AND BAD TRAVEL CONDITIONS ON AREA ROADS AND SIDE WALKS. WITH TIME...TEMPERATURES AND DEW POINTS IN THE MID TO UPPER 30S SHOULD SLOWLY WARM THE GROUND ENOUGH TO LIMIT ICING OVERNIGHT...BUT BY THIS TIME MOST OF THE PRECIP SHOULD BE DONE ANYWAYS. THE OTHER CONCERN WE ARE WATCHING OVER THE NEXT FEW HOURS IS THAT OF DENSE FOG. SEVERAL SITES ACROSS EASTERN IOWA AND INTO NORTHWESTERN ILLINOIS ARE REPORTING VISIBILITIES DROPPING DOWN AROUND A QUARTER MILE IN FOG. IT APPEARS THE MAIN THREAT FOR DENSE FOG WILL FOLLOW CLOSELY WITH THE TRACK OF THE SURFACE LOW...WHICH IS EXPECTED TO PUSH RIGHT ACROSS NORTHWESTERN ILLINOIS AND SOUTHERN WISCONSIN TONIGHT. SOME OF THIS DENSER FOG COULD GET INTO MY WESTERN AREAS. HOWEVER...I AM A LITTLE RELUCTANT TO ISSUE A DENSE FOG ADVISORY FOR THESE AREAS AS IT APPEARS THE DENSER FOG MAY BE SHORT LIVED...ONLY LASTING A COUPLE HOURS...WITH CONDITIONS IMPROVING RAPIDLY WITH THE PASSAGE OF THE SURFACE LOW AND COLD FRONT. I WILL CONTINUE TO MONITOR THE TRENDS...AND I MAY JUST COVER WITH AN SPS UNLESS IT BECOMES CLEAR THAT THE FOG COULD LAST A BIT LONGER. KJB //PREV DISCUSSION... 624 PM CST WE DECIDED TO ISSUE A FREEZING RAIN ADVISORY THROUGH THIS EVENING. ALTHOUGH AIR TEMPERATURES CONTINUE TO WARM TO NEAR 40...THE COLD GROUND IS ALLOWING AREA ROADS TO BECOME ICY. WE RECEIVED NUMEROUS REPORTS OF ACCIDENTS AND EVEN CLOSED HIGHWAYS ACROSS NORTH CENTRAL ILLINOIS. THE ILLINOIS STATE POLICE IS URGING DRIVERS TO STAY HOME THIS EVENING ACROSS NORTH CENTRAL ILLINOIS. GIVEN HOW BAD CONDITIONS APPEAR TO BE...WE HAVE OPTED TO GO WITH A FREEZING RAIN ADVISORY IN SPITE OF CONTINUED WARMING. WITH TIME THE ROAD TEMPS SHOULD WARM AND END THE THREAT FOR ICING. KJB && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 06Z... * IFR OR LOWER CIGS AND OCCASIONALLY VSBY OVERNIGHT * VSBY RETURNS TO VFR AFTER SUNRISE SHORTLY AFTER WIND SHIFT TO WEST * IFR CIGS LIKELY TO PERSIST THROUGH LATE MORNING WITH POSSIBLE IMPROVEMENT TO MVFR SATURDAY AFTERNOON IZZI //DISCUSSION...UPDATED 06Z... AREAS OF RAIN WILL CONTINUE TO AFFECT THE CHGO METRO TERMINALS THRU EARLY PART OF THE OVERNIGHT HOURS. IFR/LIFR CIGS WILL PERSIST IN THE MOIST SOUTHERLY WINDS TONIGHT IN ADVANCE OF APPROACHING COLD FRONT WITH AREAS OF IFR VSBY EXPECTED THROUGH REST OF THE OVERNIGHT HOURS. COLD FRONT SHOULD MOVE THROUGH RFD AROUND 09Z AND THROUGH CHGO METRO AROUND 11Z WITH WIND SHIFT TO WEST AND A SLOW FILTERING IN OF SLIGHTLY DRIER CONDITIONS RESULTING IN IMPROVING VSBY EARLY SATURDAY MORNING. STRATUS (MOSTLY IFR) EXTENDS BACK ACROSS ALL OF IOWA AND IS UNLIKELY TO MIX OUT SATURDAY...SO WOULD ANTICIPATE LOW CIGS TO HANG AROUND INTO SATURDAY AFTERNOON AND POSSIBLY INTO EVENING. SOME IMPROVEMENT TO LOW END MVFR IS POSSIBLE SATURDAY AFTERNOON. IZZI //ORD AND MDW CONFIDENCE...UPDATED 06Z... * HIGH CONFIDENCE IN IFR CIGS THROUGH AT LEAST MID MORNING SATURDAY * LOW CONFIDENCE IN IMPROVEMENT TO MVFR SATURDAY * NO CONFIDENCE IN CIGS SATURDAY EVENING * LOW CONFIDENCE IN VSBY TRENDS REST OF THE OVERNIGHT...HIGH CONFIDENCE IN VSBY SATURDAY * HIGH CONFIDENCE IN WIND FORECAST IZZI //OUTLOOK FOR ORD/MDW FOR 12Z SUNDAY-12Z FRIDAY...UPDATED 00Z... SUNDAY...STRONG SOUTH WINDS...LLWS POSSIBLE AFTERNOON/EARLY EVENING. VFR PROBABLE. MONDAY...VFR. TUESDAY...CHANCE OF SNOW/IFR. WEDNESDAY AND THURSDAY...VFR PROBABLE. MDB && .MARINE... 155 AM CST APPEARS AS THOUGH WE WILL ENTER ANOTHER BUSY PERIOD ON LAKE MICHIGAN WITH SEVERAL BOUTS OF GALES EXPECTED OVER THE NEXT WEEK AND ONLY BRIEF TIME WINDOWS OF LIGHTER WINDS. A MODERATELY STRONG WEST WIND WILL DEVELOP TODAY IN THE WAKE OF LOW PRESSURE DEPARTING THE REGION WITH A BRIEF LULL IN THE WINDS LATE TONIGHT INTO EARLY SUNDAY MORNING AS THEY BACK TO SOUTHWEST. AN INTENSE AND FAST MOVING LOW WILL RACE EAST ACROSS CANADA SUNDAY RESULTING IN A PERIOD OF SOUTH GALES...PROBABLY HIGHER END GALES OVER NORTHERN PORTIONS OF THE LAKE SUNDAY AFTERNOON AND EVENING. WHILE WINDS SHOULD EASE BELOW GALE FORCE BY MONDAY MORNING THEY SHOULD REMAIN FAIRLY STRONG THROUGH THE DAY MONDAY. TRACK/TIMING DIFFERENCES EXIST REGARDING A FAIRLY STRONG CLIPPER RACING SOUTHEAST INTO THE MIDWEST TUESDAY WITH ANOTHER PERIOD OF STRONG NORTHERLY WINDS AND POSSIBLE GALES IN THE WAKE OF THAT SYSTEM LATE TUESDAY OR EARLY WEDNESDAY. YET ANOTHER PERIOD OF GALES LOOKS LIKE A GOOD BET BY THURSDAY. IZZI && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...NONE. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion National Weather Service Lincoln IL 1147 PM CST Fri Jan 10 2014 .DISCUSSION... ISSUED 900 PM CST Fri Jan 10 2014 Dense fog potential will increase as the cold front progresses across Illinois. We already issued a dense fog advisory for areas NW of the IL river, but the latest runs of the RAP and HRRR both show dense fog developing after midnight across nearly all of the remainder of the KILX CWA. Forecast soundings and current dewpoint depressions support that scenario, so may need to expand the advisory eastward by late evening. Upstream obs along the southern portion of the cold front are not as supportive of dense fog farther southeast, but we have had more snow melt from a deeper snow pack in our areas. Steady rainfall has generally become confined to areas southeast of I-70. A secondary batch of rain has redeveloped from STL to Jacksonville and is progressing to the ENE into our area. It should mainly affect areas along and southeast of I-55 over the next 4-6 hours. Colder air arriving behind the cold front will have the potential to change any lingering sprinkles or light rain west of I-55 into snow. However, subsidence should prevail by that time and precip should be minimal after the cold air arrives. Low temperatures are expected to dip below freezing NW of the IL river, with around freezing east to the I-55 corridor. That could help create some slippery conditions on untreated and secondary roads. Updates to the forecast grids this evening mainly covered the addition of fog and dense fog, as well as minor low temp adjustments. We also added slight chance of rain or snow lingering in the NE early Sat morning. The remainder of the forecast looks on track. Updated info will be available shortly. Shimon && .AVIATION... ISSUED 1147 PM CST Fri Jan 10 2014 The cold front is just arriving in far western IL as of 05z, and will progress eastward across the terminal sites over the next 5-6 hours. Dense fog has begun to expand eastward with BMI and CMI down to 1/4SM FG. HRRR and RAP hi-res models still show widespread coverage of dense fog across a majority of central IL overnight, gradually clearing from the west late, with PIA vis improving to vfr after 11z. Have gone more pessimistic with vis across the board through sunrise, with the VLIFR mainly across the north. SPI and DEC have dodged the dense fog so far, but can not rule out a brief period of FG the rest of the night. Dense fog may linger at CMI to 13z, then clear out to VFR quickly. Clouds will remain in the IFR/LIFR range through much of the morning. Some VLIFR may continue at BMI until after sunrise as well. Clouds should improve to MVFR Sat afternoon, with a clearing line expected to push across the area by Sat evening. Winds will shift from S-SW to W with the cold fropa, with winds shifting at PIA around 07-08z, and at CMI toward 12z. Wind speeds should remain steady in the 09-13kt range overnight, with gusts to 22-24kt returning Sat morning as mixing deepens. Shimon && .PREV DISCUSSION... ISSUED 253 PM CST Fri Jan 10 2014 Main issues for this forecast package include the rain tonight and then more chances for end of the weekend and beginning of next week. Models look in pretty good agreement through about 66hrs but then differ with intensity of next system and the resulting precip. Extended models do begin to look better once we get to the end of next week. So, confidence in forecast in the near term is good, but wanes with the next system(s) for the end of the weekend and the beginning of next week. So, will take a blend for now. SHORT TERM...Tonight through Monday Rain will continue to move across the area tonight and should begin to wane after midnight, and then be east and northeast of the area by morning. By then, the low pressure area associated with the pcpn will have moved into the Grt Lks region and the 500mb trough will be pushing through the region. So, beyond tonight, dry weather is expected for tomorrow through Sunday. After some ridging, another weak front will move into the area late Sunday night. The return of moisture ahead of this system looks weak and doesn`t seem to arrive until the frontal system is about halfway through the area. So will have chance of pcpn for Monday in the east and southeast only. Will also have a slight chc of pcpn for Sun night, but this will not show up in the worded forecast. Pcpn type should also be just rain as temps should be warm enough through the atmosphere to support all liquid and nothing frozen, and surface temps will be above freezing. Temps will continue to warm as area sits in a somewhat zonal pattern for the weekend. Guidance numbers look ok, but went a little warmer in the southeast for tonight. LONG TERM...Monday night through Friday The beginning of the extended is where the models really look different. The GFS brings another wave down across the area for Monday night through Tue, while the ECMWF has stronger southern stream energy that holds some pcpn back for Monday night and into Tuesday. Because of the differences, not confident enough to put chc pops in the forecast at this time. So will just have slight chc pops for the time period. Both models show a second wave/trough coming into the area from the northwest, so little bit cooler weather will move into the region. This will cause the pcpn type to be more of snow or rain/snow mix in the south part of the cwa. However, since this will be slight chc, the pops will not be seen in the worded forecast. But cloudy skies will be mentioned. Remainder of the extended period, and next week, will be dry. GFS brings additional chances of pcpn through the area, but ECMWF does not. For now, going with a dry forecast seems best. Temps will slightly warmer for Tue, but then become cooler again for Wed and again on Friday. MEX numbers seem to have a good handle on this currently. Auten && .ILX WATCHES/WARNINGS/ADVISORIES... DENSE FOG ADVISORY until 6 AM CST Saturday FOR ILZ027>030-036- 040. && $$
AREA FORECAST DISCUSSION
NWS RALEIGH NC
650 AM EST SAT JAN 11 2014 .SYNOPSIS...AS HIGH PRESSURE MOVES FARTHER OFFSHORE...A VIGOROUS COLD FRONT MOVES ACROSS THE REGION TODAY AND THIS EVENING. HIGH PRESSURE QUICKLY BUILDS BACK INTO THE REGION SUNDAY BEHIND THE COLD FRONT. ANOTHER COLD FRONT APPROACHES FROM THE WEST LATE MONDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 305 AM SATURDAY... DEEP UPPER TROUGH WAS MOVING EAST ON WATER VAPOR IMAGERY EARLY THIS MORNING TOWARD THE MISSISSIPPI RIVER...AND THIS TROUGH WILL MOVE ACROSS CENTRAL NORTH CAROLINA OVERNIGHT TONIGHT. IN ADVANCE...THE LATEST SURFACE ANALYSIS SHOWED A WEDGE FRONT ESSENTIALLY BISECTING CENTRAL NORTH CAROLINA...WITH TEMPERATURES STILL LINGERING IN THE UPPER 30S IN THE IMMEDIATE TRIAD...TO THE MID 60S TOWARD KCTZ. IN FACT...THE TEMPERATURE AT KRDU WAS IN THE MID 40S WHILE THE TEMPERATURE AT THE NWS OFFICE TO THE EAST ACROSS TOWN WAS NEAR 60. THE WEDGE SHOULD START TO BREAK DOWN IN ADVANCE OF THE COLD FRONT...BUT IT COULD BE A SLOW PROCESS...AND WILL STAY ON THE COOLER SIDE OF GUIDANCE WITH THE HIGH TODAY IN THE TRIAD. FROM U.S. 1 EAST...ANTICIPATE ENOUGH WARM ADVECTION THAT TEMPERATURES SHOULD RISE TO VALUE NEAR 70 TO THE MID 70S...WARMEST FAR SOUTHEAST. WILL NOTE RECORD HIGHS AT KRDU OF 75 AND KFAY OF 79 BOTH SET IN 1930. NOT GOING THAT WARM...AND NONE OF THE GUIDANCE SUGGESTS THAT LEVEL OF WARMTH CURRENTLY. THE WARMTH...THOUGH...WILL HELP IN DEVELOPING SOME INSTABILITY DURING THE LATE MORNING AND AFTERNOON. THE GFS IS MORE UNSTABLE THAN THE RAP...WITH THE FORMER SUGGESTING LIFTED INDICES FALLING TO -2C TO -4C ALONG AND EAST OF U.S. 1 BY THE AFTERNOON...ALONG WITH 700J/KG OF CAPE IN THE LOWEST KM AS A STRONG 700MB SHORTWAVE MOVES INTO THE AREA...AHEAD OF A 110KT 500MB JET AND WINDS OF AT LEAST 65KT AT 850MB. THE RAP ONLY FORECASTS ABOUT 200J/KG OF SURFACE-BASED CAPE...BUT EVEN WITH THE CAPE FORECAST OF THE RAP...AND THE LIMITED MIXING ON THE GFS BUFR SOUNDINGS...THERE COULD EXIST ENOUGH BOUNDARY LAYER INSTABILITY WITH THE STRONG WINDS ALOFT AND 60KT OF 0-3KM SHEAR THAT A STRONGLY FORCED LINE OF SHOWERS...WITH ISOLATED THUNDER...MOVES ACROSS CENTRAL NORTH CAROLINA MAINLY THIS AFTERNOON. THE SPC OUTLOOK CONTINUES TO NOTE A SLIGHT RISK FOR CENTRAL NORTH CAROLINA AND THIS SEEMS REASONABLE...AND WILL CONTINUE THE MENTION OF A DAMAGING WIND THREAT FOR MOST OF CENTRAL NORTH CAROLINA IN THE HWO. AS DRY AND MORE STABLE AIR MOVES WEST TO EAST ACROSS THE AREA...ANY SEVERE THREAT SHOULD DIMINISH BY EARLY EVENING IN THE COASTAL PLAIN. CANNOT COMPLETELY RULE OUT AN ISOLATED TORNADO GIVEN THE 0-3KM HELICITY FORECAST BY THE GFS BETWEEN 100 AND 300M2/S2... WITH SIMILAR VALUES FORECAST BY THE LATEST RAP. IN TERMS OF OTHER ITEMS TO CONSIDER...MANY AREAS OF FOG THIS MORNING ACROSS CENTRAL NORTH CAROLINA BUT VISIBILITIES WERE PRIMARILY ABOVE A HALF-MILE. A FEW POCKETS OF VISIBILITY FROM A HALF-MILE OR LESS. FOR NOW AM NOT PLANNING A DENSE FOG ADVISORY...BUT WILL CONTINUE TO MONITOR THIS. IN ADDITION...AS THE SURFACE GRADIENT TIGHTENS THIS AFTERNOON AHEAD OF THE FRONT...WILL CONTINUE TO ANTICIPATE WITH MIXING GRADIENT WIND GUSTS TO 35MPH. TONIGHT...MORE STABLE AIR MOVES INTO CENTRAL NORTH CAROLINA WITH THE GFS BUFR SOUNDINGS FAIRLY SUBSIDENT BY 06Z. LINGERING SHOWERS...AND A POSSIBLE THUNDERSTORM IN THE COASTAL PLAIN EARLY TONIGHT... DIMINISH WEST-TO-EAST AS PRECIPITABLE WATER VALUES FALL TO AROUND A QUARTER-INCH BY 12Z SUNDAY. THE STRONG UPPER TROUGH WILL BE PUSHING THROUGH CENTRAL NORTH CAROLINA AND EXPECT A FEW MID-LEVEL CLOUDS ASSOCIATED WITH IT...BUT MODELS ARE STRONGLY DRY DURING THE OVERNIGHT HOURS. OVERNIGHT LOWS UPPER 30S IN THE TRIAD TO THE MID 40S TOWARD KCTZ...AROUND 40 IN THE U.S. 1 CORRIDOR. && .SHORT TERM /SUNDAY THROUGH TUESDAY/... AS OF 305 AM SATURDAY... SUNDAY...SUBSIDENCE CONTINUES OVERALL...WITH PRECIPITABLE WATER VALUES FALLING BELOW A QUARTER-INCH SUNDAY UNDER BUILDING HIGH PRESSURE SURFACE AND ALOFT. WITH MIXING...THE GFS BUFR SOUNDINGS SUGGEST A FEW WIND GUSTS TO AROUND 20KT SUNDAY BEFORE WINDS SLACKEN AS THE MID-LEVEL TROUGH PULLS AWAY TO THE EAST AND SURFACE HIGH PRESSURE BUILDS OVERHEAD. HIGHS IN THE MID 50 TO AROUND 60. SUNDAY NIGHT...THE MID-LEVEL RIDGE AXIS MOVES EAST WHICH COULD ALLOW A RETURN OF A FEW HIGH CLOUDS INTO CENTRAL NORTH CAROLINA DURING THE OVERNIGHT HOURS AS THE UPPER FLOW BACKS SOUTHWEST. THE RELATIVELY STRONGER 300MB WINDS REMAIN SOUTHWEST OF CENTRAL NORTH CAROLINA SUNDAY NIGHT THROUGH 12Z MONDAY...THOUGH...SO ANY HIGH CLOUDS THAT MOVE IN SHOULD BE SCATTERED TO POSSIBLY THIN BROKEN AT TIMES. OVERNIGHT LOWS IN THE 30S...COOLEST AND CLOSE TO FREEZING IN SOME OF THE TYPICALLY COOLER LOCATIONS OF THE NORTHEAST PIEDMONT AND THE NORTHERN COASTAL PLAIN. -DJF A SHORTWAVE TROUGH IN PROGRESSIVE FLOW ALOFT WILL AMPLIFY ACROSS THE PLAINS AND MS VALLEY MONDAY...WITH PRECEDING SOUTHWESTERLY FLOW ALOFT YIELDING CONSIDERABLE MID-HIGH CLOUDINESS DOWNSTREAM ACROSS THE CAROLINAS AND MIDDLE ATLANTIC. DESPITE THE INCREASING CLOUDINESS...TEMPERATURES WILL TREND ABOVE AVERAGE BY SOME 8-12 DEGREES...IN RETURN SSW FLOW AROUND PROGRESSIVE SURFACE HIGH PRESSURE IN THE WESTERN ATLANTIC. MODEL DIFFERENCES THAT DEVELOP EARLY IN THE PERIOD - SIMILAR TO THOSE EVIDENT DURING THE PAST SEVERAL MODEL ITERATIONS - CONTINUE TO PLAGUE THE MON NIGHT-TUE TIME FRAME. THAT IS...THE ECMWF AND ASSOCIATED ENSEMBLE MEMBERS FAVOR A SLOWER TROUGH PROGRESSION...WITH MORE SOUTHERN STREAM DOMINANCE...AND CONSEQUENTLY ALLOW FOR MORE APPRECIABLE MOISTURE TRANSPORT FARTHER INLAND THAN A MORE SUPPRESSED/OFFSHORE GFS AND GFS ENSEMBLE MEAN SOLUTION. WILL FOLLOW PREVIOUS FORECAST CONTINUITY AND CONTINUED WPC PREFERENCE TOWARD THE WETTER-FOR CENTRAL-NC ECMWF SOLUTIONS...AND AS SUCH...CARRY A HIGH CHANCE TO LOW LIKELY PROBABILITY OF RAIN MON NIGHT-TUE...WITH PRECIPITATION AMOUNTS IN THE QUARTER TO HALF INCH RANGE. CONTINUED RELATIVELY MILD...WITH TEMPERATURES ABOUT 10 DEGREES ABOVE AVERAGE. && .LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/... AS OF 305 AM SATURDAY... MODEL DIFFERENCES CONTINUE INTO THE MEDIUM RANGE/LONG TERM...WITH THE ECMWF AND ASSOCIATED ENSEMBLE MEMBERS ON THE SLOWER AND MORE AMPLIFIED ENVELOPE OF SOLUTIONS REGARDING A TRAILING SHORTWAVE TROUGH AND ASSOCIATED STRONG CLIPPER SURFACER LOW FORECAST TO MIGRATE ACROSS THE UPPER MIDWEST AND LOWER GREAT LAKES...AND SOME DEGREE OF SECONDARY COASTAL CYCLOGENESIS ALONG THE MIDDLE ATLANTIC COAST CENTERED AROUND WED. SINCE THE SHORTWAVE TROUGH IN QUESTION IS AN ELONGATED AXIS OF SHEAR VORTICITY SOUTHWEST OF THE ALEUTIANS...IN A REGION OUTSIDE OF THE DOMAIN OF THE EC AND GFS MODEL DATA AVAILABLE TO RAH...IT IS DIFFICULT TO HAVE A PREFERENCE TOWARD ONE CLUSTER OF SOLUTIONS OVER THE OTHER. BOTH CLUSTERS OF SOLUTIONS ARE RELATIVELY MOISTURE-STARVED THROUGH A DEEP LAYER AT OUR LATITUDE - NOT SURPRISING SINCE THE PRIMARY VORT AND CLIPPER SFC LOW PASS TO OUR NORTH - SO WE WILL ACCORDINGLY MAINTAIN THE FLAVOR OF THE PREVIOUS FORECAST...WITH JUST A SLIGHT CHANCE OF PRECIPITATION CENTERED ON THE DAY WED. THERMAL PROFILES INDEED APPEAR QUITE COLD...PARTICULARLY ABOVE THE BOUNDARY LAYER (IN THE H85-7 LAYER)..CHARACTERISTIC OF STEEP LAPSE RATE ALOFT/MOISTURE-STARVED SYSTEMS. THE NON-SPECIFIC MENTION OF "RAIN OR SNOW" WILL SUFFICE UNTIL A CLEARER MODEL PREFERENCE AND/OR CONSENSUS BECOMES APPARENT. CLEARING IN BRIEF MODIFIED POLAR HIGH PRESSURE WILL FOLLOW FOR THU...IN ADVANCE OF YET ANOTHER SHARPENING TROUGH ALOFT AND APPROACHING MOISTURE-STARVED SURFACE FRONTAL ZONE IN CONTINUED STRONGLY PROGRESSIVE FLOW ALOFT...FOR THE END OF THE WEEK. && .AVIATION /12Z SATURDAY THROUGH WEDNESDAY/... AS OF 650 AM SATURDAY... WIDESPREAD IFR TO VLIFR CONDITIONS CONTINUED OVER CENTRAL NORTH CAROLINA EARLY THIS MORNING WITH RAIN BECOMING MORE SCATTERED FOR A PERIOD AS IT TRANSITIONED TO A MORE SHOWERY CHARACTER. LOW-LEVEL WIND SHEAR REMAINED A CONCERN TOWARD THE TRIAD...WITH WIND SPEEDS STILL FAIRLY LIGHT AND NORTHERLY AT THE SURFACE THERE...VEERING RAPIDLY TO THE SOUTH AROUND 40KT BY 2000FT. IN ADDITION...ELEVATED THUNDERSTORMS WERE MOVING TOWARD THE TRIAD AND HAVE NOTED A TEMPORARY CONDITION WITH THUNDER IN THE KINT AND KGSO TAFS EARLY THIS MORNING. DURING THE REST OF THE DAY...A VIGOROUS COLD FRONT MOVES ACROSS THE AREA WITH A LIKELY BAND OF SHOWERS...AND AT LEAST ISOLATED THUNDERSTORMS. GUSTY WINDS WITH THE BAND ARE POSSIBLE IN THE TRIAD...BUT INSTABILITY INCREASES TO THE EAST...AND IT IS NOTED IN THE FORECASTS FOR KRDU...KFAY...AND KRWI WEST GUSTS TO 40KT DURING THE AFTERNOON WHEN IT IS EXPECTED A STRONGLY-FORCED LINE WILL MOVE ACROSS CENTRAL NORTH CAROLINA. NOTED SIMILAR CONDITIONS IN THE TRIAD WITH THE EXPECTED BAND...JUST SLIGHTLY LESS IN TERMS OF THE SPEED OF THE WESTERLY WIND GUSTS DUE TO LESSER INSTABILITY THERE. RAPID DRYING TAKES PLACE LATE THIS AFTERNOON AND THIS EVENING...WITH CONDITIONS RETURNING TO VFR WEST-TO-EAST ACCOMPANIED BY A NOTICEABLE WEST WIND THAT REMAINS FOR MUCH OF THE NIGHT. WEST-NORTHWEST GUSTS TO AROUND 20KT ARE POSSIBLE WITH MIXING SUNDAY BEFORE WINDS DIMINISH SUNDAY AFTERNOON. FOR MONDAY THROUGH WEDNESDAY...A PERIOD OF SUB-VFR CONDITIONS IS POSSIBLE MONDAY NIGHT INTO EARLY TUESDAY WITH A CHANCE OF LIGHT RAIN. ANOTHER PERIOD OF SUB-VFR CONDITIONS COULD OCCUR LATE TUESDAY NIGHT INTO EARLY WEDNESDAY. LIGHT PRECIPITATION IS POSSIBLE THEN AS WELL. && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...DJF NEAR TERM...DJF SHORT TERM...DJF/MWS LONG TERM...MWS AVIATION...DJF
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
858 AM EST SAT JAN 11 2014 .SYNOPSIS... LOW PRESSURE OVER THE CENTRAL GREAT LAKES REGION WILL MOVE NORTHEAST TO WESTERN QUEBEC THIS EVENING. A COLD FRONT SOUTH FROM THE LOW WILL MOVE EAST ACROSS THE AREA TODAY. SUNDAY...HIGH PRESSURE OVER THE GULF COAST STATES WILL BUILD ACROSS THE AREA. ANOTHER COLD FRONT WILL FOLLOW ON MONDAY. && .NEAR TERM /THROUGH TONIGHT/... SECONDARY COLD FRONT OVER INDIANA REGENERATING SHOWERS TO THE WEST AS THE PRIMARY FRONT PUSHES EAST OF YOUNGSTOWN. SOME FOG DEVELOPED IN THE MORE STABLE AIR ON THE BACKSIDE OF THE INITIAL FRONT OVER NORTHWEST OH NEAR TOLEDO. WITH THE APPROACH OF THE SECOND FRONT WE EXPECT THIS TO IMPROVE OVER THE NEXT HOUR. THE SHOWERS WILL OVERSPREAD THE AREA BUT WE AREN`T LOOKING AT SIGNIFICANT AMOUNTS OF PRECIPITATION...PERHAPS A FEW MORE TENTHS OF AN INCH TODAY. WITH THE PASSAGE OF THE FRONT THIS AFTERNOON THROUGH EARLY EVENING WE WILL SEE TEMPERATURES FALL WITH A BRIEF TRANSITION OVER TO SNOW. THE AIR WILL COOL FASTER THAN THE GROUND SO WILL SEE A FAIR AMOUNT OF MELTING BEFORE ANY OF THE SNOW BEGINS TO STICK AND ACCUMULATE...BY WHICH TIME THE MOISTURE WILL BE LIMITED. && .SHORT TERM /SUNDAY THROUGH TUESDAY NIGHT/... AGAIN USED MAINLY NAM TIMING THROUGH THE SHORT TERM BLENDING INTO THE GFS TUESDAY. FOR TONIGHT MODELS SHOW THE UPPER TROF ACROSS THE GREAT LAKE SHIFTING EAST THROUGH THE NIGHT AS A SHORT WAVE RIDGE BUILDS IN. HIGH PRESSURE ACROSS THE GULF COAST STATES WILL ALSO EXTEND NORTH INTO THE OHIO VALLEY. WILL BEGIN WITH CLOUDS ACROSS THE EAST HALF OF THE AREA WHERE THE DEEPEST MOISTURE REMAINS AT 12Z HOWEVER IN THE WEST WILL DROP CLOUDS TO PC IN THE MORNING. FOR THE AFTERNOON WILL DECREASE CLOUDS IN THE EAST AS WELL. NEXT SYSTEM WILL COME MONDAY. LOW PRESSURE WILL MOVE EAST ACROSS ONTARIO MONDAY REACHING JAMES BAY BY EVENING. THE ASSOCIATED COLD FRONT WILL MOVE EAST ACROSS THE AREA DURING THE DAY MONDAY. THE NAM DEVELOPS MOST OF THE PRECIP ACROSS THE EASTERN HALF OF THE AREA AS A SURGE OF MOISTURE MOVING OUT OF THE GULF COAST MERGES WITH THE FRONT MOVING THROUGH THE AREA. THE GFS DOESNT SHOW THIS AS AGGRESSIVELY HOWEVER SO WHILE THE HIGHEST POPS ARE ACROSS THE EAST IN THE AFTERNOON DID BACK OFF LIKELY TO HIGH CHANCE NUMBERS. AFTER A 6 TO 12 HOURS BREAK MODELS BRING A CLIPPER THROUGH THE AREA. THE GFS IS A BIT FASTER AT 12Z TUESDAY WITH THE MOISTURE AND SURFACE LOW SO SPLIT THE DIFFERENCE AND BROUGHT SNOW IN CLOUDS BUT ESSENTIALLY BOTH MODELS WOULD SUGGEST SNOW SOMETIME TUESDAY CONTINUING TUESDAY NIGHT. FAIRLY MILD TEMPS...COOLING OFF MID WEEK. && .LONG TERM /WEDNESDAY THROUGH FRIDAY/... SEASONAL TEMPERATURES WEDNESDAY THROUGH FRIDAY. BETTER AGREEMENT ON THE PATH OF LOW PRESSURE FROM WESTERN CANADA STAYING NORTH OF THE GREAT LAKES FOR THURSDAY. RIDGING WEDNESDAY WILL PROVIDE FOR RELATIVELY FAIR WEATHER...ALTHOUGH A FEW LIGHT SNOW SHOWERS MAY LINGER ACROSS NE OH/NW PA TO START. THE WARM FRONT EARLY THURSDAY MORNING DOES NOT HAVE A BIG PUSH OF WARM AIR WITH IT AND WILL MODERATE TEMPS ONLY TO NEAR FREEZING. AT THIS POINT IT LOOKS LIKE PRECIP ARRIVES THURSDAY NIGHT AND LINGERS INTO FRIDAY. AT THIS POINT AN EASTERN U.S. TROUGH WILL HAVE RETURNED TO END THE WEEK. && .AVIATION /12Z SATURDAY THROUGH WEDNESDAY/... LOW CONFIDENCE FORECAST CONTINUES. MOST MODEL GUIDANCE WOULD HAVE HAD US ALL IFR/MFR THROUGH THE NIGHT AND INSTEAD MOST LOCATIONS HAVE BEEN MVFR/VFR WITH THE EXCEPTION OF TOL. EARLY MORNING RUNS OF THE HRRR COME IN CLOSEST TO CURRENT REALITY SO HAVE LEANED THAT DIRECTION WITH THE FORECAST. MAIN AREA OF RAIN WILL EXIT EAST DURING THE FIRST PART OF THE MORNING. SCATTERED SHOWERS WILL REMAIN IN ITS WAKE WITH A COLD FRONT CROSSING TOL LATE MORNING...AND ERIE EARLY EVENING. FOG AND LOW STRATUS LURK TO THE WEST ACROSS NW OH AND MI/IND AHEAD OF THE COLD FRONT. HRRR DID NOT REALLY GET THIS IFR PAST THE I-71 CORRIDOR AND CLE/MFD. ALL OTHERS JUST DROP TO MVFR LATER. SLOW IMPROVEMENT OVERNIGHT...BUT REMAINING MVFR OVERCAST THROUGH 12Z SUN. PRECIPITATION CHANCES AFTER 00Z SUN VERY LIMITED AND LEFT OUT OF TAF FORECAST. SOUTHERLY WINDS WILL SHIFT SLIGHTLY TO THE SOUTHWEST AND THEN TO THE WEST LATER. GUSTS WILL DEVELOP OF 20 TO 25 KNOTS...SUBSIDING OVERNIGHT. OUTLOOK...SOME NON VFR MON THRU WED. && .MARINE... SOUTH FLOW SHIFT SOUTHWEST WITH THE PASSAGE OF A COLD FRONT. SOME COLD AIR ADVECTION MAY AID IN ALLOWING WINDS TO MIX DOWN AND YIELD GALE FORCE WINDS FOR THE EASTERN TWO THIRDS OF THE LAKE. WILL CONTINUE THE GALE WARNING THAT WAS PREVIOUSLY ISSUED FOR LATER THIS AFTERNOON AND EVENING. THIS MAY CAUSE SHIFTING/RIDGING/RAFTING OF ICE ON THE LAKE. SOUTHWEST WINDS DIMINISH FOR SUNDAY AS A RIDGE MOVES OVERHEAD. MONDAYS COLD FRONT WILL ONLY SHIFT WINDS FROM THE SOUTH TO THE SOUTHWEST. LOW PRESSURE FROM THE NORTHERN PLAINS TAKES A PATH ACROSS THE MIDWEST AND LOWER GREAT LAKES EITHER TUESDAY OR WEDNESDAY. WINDS WILL FINALLY GO NORTHWEST AFTER THE PASSAGE OF THIS SYSTEM. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...GALE WARNING FROM 4 PM THIS AFTERNOON TO 5 AM EST SUNDAY FOR LEZ061-144>149-164>169. && $$ SYNOPSIS...TK NEAR TERM...JAMISON/TK SHORT TERM...TK LONG TERM...OUDEMAN AVIATION...OUDEMAN MARINE...OUDEMAN
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
653 AM EST SAT JAN 11 2014 .SYNOPSIS... LOW PRESSURE OVER THE CENTRAL GREAT LAKES REGION WILL MOVE NORTHEAST TO WESTERN QUEBEC THIS EVENING. A COLD FRONT SOUTH FROM THE LOW WILL MOVE EAST ACROSS THE AREA TODAY. SUNDAY...HIGH PRESSURE OVER THE GULF COAST STATES WILL BUILD ACROSS THE AREA. ANOTHER COLD FRONT WILL FOLLOW ON MONDAY. && .NEAR TERM /THROUGH TONIGHT/... UPDATE...UDJUSTED POPS BASED ON RADAR. ALSO BROUGHT LIKELY POPS BACK TO THE NORTHWEST FOR A TIME LATE THIS MORNING AS SHOWERS FROM NRN INDIANA GET INTO THE AREA. BOOSTED HIGHS A COUPLE DEGREES AS WELL. ORIGINAL...USED A COMBINATION OF THE NAM AND THE HRRR FOR THE NEAR TERM FROM THE PREDAWN HOURS THROUGH THE DAY. WILL BEGIN WITH CATEGORICAL POPS EVERYWHERE BUT WILL BEGIN TO TAPER ALMOST IMMEDIATELY FROM THE WEST BEHIND THE COLD FRONT. RADAR SHOWING WHAT THE EARLIER HRRR HINTED AT WITH THE FIRST SURGE HAVING EXITED TO THE NORTHEAST AND THE SECOND SURGE OF PRECIP MOVING IN. AND YET ANOTHER WAVE NEAR THE OHIO RIVER. EVENTUALLY THIS MAY ALL BLEND TOGETHER EARLY THIS MORNING WITH THE HEAVIEST RAINFALL ACROSS THE CENTRAL COUNTIES OF THE CWA...WITH THE FOCUS MOVING TO THE EASTERN COUNTIES AROUND/AFTER DAWN. BY 15Z BROUGHT POPS TO CHANCE IN THE FAR WEST. MODELS DO SHOW ANOTHER SURFACE TROF/SHORT WAVE ALOFT ROTATING THROUGH THE AREA THAT COULD BRING A FEW SHOWERS TO THE AREA AGAIN IN THE AFTERNOON. AS FOR TEMPS...EXPECT HIGHS TO BE IN THE MORNING WITH TEMPS FALLING DURING MUCH OF THE DAY. && .SHORT TERM /SUNDAY THROUGH TUESDAY NIGHT/... AGAIN USED MAINLY NAM TIMING THROUGH THE SHORT TERM BLENDING INTO THE GFS TUESDAY. FOR TONIGHT MODELS SHOW THE UPPER TROF ACROSS THE GREAT LAKE SHIFTING EAST THROUGH THE NIGHT AS A SHORT WAVE RIDGE BUILDS IN. HIGH PRESSURE ACROSS THE GULF COAST STATES WILL ALSO EXTEND NORTH INTO THE OHIO VALLEY. WILL BEGIN WITH CLOUDS ACROSS THE EAST HALF OF THE AREA WHERE THE DEEPEST MOISTURE REMAINS AT 12Z HOWEVER IN THE WEST WILL DROP CLOUDS TO PC IN THE MORNING. FOR THE AFTERNOON WILL DECREASE CLOUDS IN THE EAST AS WELL. NEXT SYSTEM WILL COME MONDAY. LOW PRESSURE WILL MOVE EAST ACROSS ONTARIO MONDAY REACHING JAMES BAY BY EVENING. THE ASSOCIATED COLD FRONT WILL MOVE EAST ACROSS THE AREA DURING THE DAY MONDAY. THE NAM DEVELOPS MOST OF THE PRECIP ACROSS THE EASTERN HALF OF THE AREA AS A SURGE OF MOISTURE MOVING OUT OF THE GULF COAST MERGES WITH THE FRONT MOVING THROUGH THE AREA. THE GFS DOESNT SHOW THIS AS AGGRESSIVELY HOWEVER SO WHILE THE HIGHEST POPS ARE ACROSS THE EAST IN THE AFTERNOON DID BACK OFF LIKELY TO HIGH CHANCE NUMBERS. AFTER A 6 TO 12 HOURS BREAK MODELS BRING A CLIPPER THROUGH THE AREA. THE GFS IS A BIT FASTER AT 12Z TUESDAY WITH THE MOISTURE AND SURFACE LOW SO SPLIT THE DIFFERENCE AND BROUGHT SNOW IN CLOUDS BUT ESSENTIALLY BOTH MODELS WOULD SUGGEST SNOW SOMETIME TUESDAY CONTINUING TUESDAY NIGHT. FAIRLY MILD TEMPS...COOLING OFF MID WEEK. && .LONG TERM /WEDNESDAY THROUGH FRIDAY/... SEASONAL TEMPERATURES WEDNESDAY THROUGH FRIDAY. BETTER AGREEMENT ON THE PATH OF LOW PRESSURE FROM WESTERN CANADA STAYING NORTH OF THE GREAT LAKES FOR THURSDAY. RIDGING WEDNESDAY WILL PROVIDE FOR RELATIVELY FAIR WEATHER...ALTHOUGH A FEW LIGHT SNOW SHOWERS MAY LINGER ACROSS NE OH/NW PA TO START. THE WARM FRONT EARLY THURSDAY MORNING DOES NOT HAVE A BIG PUSH OF WARM AIR WITH IT AND WILL MODERATE TEMPS ONLY TO NEAR FREEZING. AT THIS POINT IT LOOKS LIKE PRECIP ARRIVES THURSDAY NIGHT AND LINGERS INTO FRIDAY. AT THIS POINT AN EASTERN U.S. TROUGH WILL HAVE RETURNED TO END THE WEEK. && .AVIATION /12Z SATURDAY THROUGH WEDNESDAY/... LOW CONFIDENCE FORECAST CONTINUES. MOST MODEL GUIDANCE WOULD HAVE HAD US ALL IFR/MFR THROUGH THE NIGHT AND INSTEAD MOST LOCATIONS HAVE BEEN MVFR/VFR WITH THE EXCEPTION OF TOL. EARLY MORNING RUNS OF THE HRRR COME IN CLOSEST TO CURRENT REALITY SO HAVE LEANED THAT DIRECTION WITH THE FORECAST. MAIN AREA OF RAIN WILL EXIT EAST DURING THE FIRST PART OF THE MORNING. SCATTERED SHOWERS WILL REMAIN IN ITS WAKE WITH A COLD FRONT CROSSING TOL LATE MORNING...AND ERIE EARLY EVENING. FOG AND LOW STRATUS LURK TO THE WEST ACROSS NW OH AND MI/IND AHEAD OF THE COLD FRONT. HRRR DID NOT REALLY GET THIS IFR PAST THE I-71 CORRIDOR AND CLE/MFD. ALL OTHERS JUST DROP TO MVFR LATER. SLOW IMPROVEMENT OVERNIGHT...BUT REMAINING MVFR OVERCAST THROUGH 12Z SUN. PRECIPITATION CHANCES AFTER 00Z SUN VERY LIMITED AND LEFT OUT OF TAF FORECAST. SOUTHERLY WINDS WILL SHIFT SLIGHTLY TO THE SOUTHWEST AND THEN TO THE WEST LATER. GUSTS WILL DEVELOP OF 20 TO 25 KNOTS...SUBSIDING OVERNIGHT. OUTLOOK...SOME NON VFR MON THRU WED. && .MARINE... SOUTH FLOW SHIFT SOUTHWEST WITH THE PASSAGE OF A COLD FRONT. SOME COLD AIR ADVECTION MAY AID IN ALLOWING WINDS TO MIX DOWN AND YIELD GALE FORCE WINDS FOR THE EASTERN TWO THIRDS OF THE LAKE. WILL CONTINUE THE GALE WARNING THAT WAS PREVIOUSLY ISSUED FOR LATER THIS AFTERNOON AND EVENING. THIS MAY CAUSE SHIFTING/RIDGING/RAFTING OF ICE ON THE LAKE. SOUTHWEST WINDS DIMINISH FOR SUNDAY AS A RIDGE MOVES OVERHEAD. MONDAYS COLD FRONT WILL ONLY SHIFT WINDS FROM THE SOUTH TO THE SOUTHWEST. LOW PRESSURE FROM THE NORTHERN PLAINS TAKES A PATH ACROSS THE MIDWEST AND LOWER GREAT LAKES EITHER TUESDAY OR WEDNESDAY. WINDS WILL FINALLY GO NORTHWEST AFTER THE PASSAGE OF THIS SYSTEM. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...GALE WARNING FROM 4 PM THIS AFTERNOON TO 5 AM EST SUNDAY FOR LEZ061-144>149-164>169. && $$ SYNOPSIS...TK NEAR TERM...TK SHORT TERM...TK LONG TERM...OUDEMAN AVIATION...OUDEMAN MARINE...OUDEMAN
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
637 AM EST SAT JAN 11 2014 .SYNOPSIS... LOW PRESSURE OVER THE CENTRAL GREAT LAKES REGION WILL MOVE NORTHEAST TO WESTERN QUEBEC THIS EVENING. A COLD FRONT SOUTH FROM THE LOW WILL MOVE EAST ACROSS THE AREA TODAY. SUNDAY...HIGH PRESSURE OVER THE GULF COAST STATES WILL BUILD ACROSS THE AREA. ANOTHER COLD FRONT WILL FOLLOW ON MONDAY. && .NEAR TERM /THROUGH TONIGHT/... USED A COMBINATION OF THE NAM AND THE HRRR FOR THE NEAR TERM FROM THE PREDAWN HOURS THROUGH THE DAY. WILL BEGIN WITH CATEGORICAL POPS EVERYWHERE BUT WILL BEGIN TO TAPER ALMOST IMMEDIATELY FROM THE WEST BEHIND THE COLD FRONT. RADAR SHOWING WHAT THE EARLIER HRRR HINTED AT WITH THE FIRST SURGE HAVING EXITED TO THE NORTHEAST AND THE SECOND SURGE OF PRECIP MOVING IN. AND YET ANOTHER WAVE NEAR THE OHIO RIVER. EVENTUALLY THIS MAY ALL BLEND TOGETHER EARLY THIS MORNING WITH THE HEAVIEST RAINFALL ACROSS THE CENTRAL COUNTIES OF THE CWA...WITH THE FOCUS MOVING TO THE EASTERN COUNTIES AROUND/AFTER DAWN. BY 15Z BROUGHT POPS TO CHANCE IN THE FAR WEST. MODELS DO SHOW ANOTHER SURFACE TROF/SHORT WAVE ALOFT ROTATING THROUGH THE AREA THAT COULD BRING A FEW SHOWERS TO THE AREA AGAIN IN THE AFTERNOON. AS FOR TEMPS...EXPECT HIGHS TO BE IN THE MORNING WITH TEMPS FALLING DURING MUCH OF THE DAY. && .SHORT TERM /SUNDAY THROUGH TUESDAY NIGHT/... AGAIN USED MAINLY NAM TIMING THROUGH THE SHORT TERM BLENDING INTO THE GFS TUESDAY. FOR TONIGHT MODELS SHOW THE UPPER TROF ACROSS THE GREAT LAKE SHIFTING EAST THROUGH THE NIGHT AS A SHORT WAVE RIDGE BUILDS IN. HIGH PRESSURE ACROSS THE GULF COAST STATES WILL ALSO EXTEND NORTH INTO THE OHIO VALLEY. WILL BEGIN WITH CLOUDS ACROSS THE EAST HALF OF THE AREA WHERE THE DEEPEST MOISTURE REMAINS AT 12Z HOWEVER IN THE WEST WILL DROP CLOUDS TO PC IN THE MORNING. FOR THE AFTERNOON WILL DECREASE CLOUDS IN THE EAST AS WELL. NEXT SYSTEM WILL COME MONDAY. LOW PRESSURE WILL MOVE EAST ACROSS ONTARIO MONDAY REACHING JAMES BAY BY EVENING. THE ASSOCIATED COLD FRONT WILL MOVE EAST ACROSS THE AREA DURING THE DAY MONDAY. THE NAM DEVELOPS MOST OF THE PRECIP ACROSS THE EASTERN HALF OF THE AREA AS A SURGE OF MOISTURE MOVING OUT OF THE GULF COAST MERGES WITH THE FRONT MOVING THROUGH THE AREA. THE GFS DOESNT SHOW THIS AS AGGRESSIVELY HOWEVER SO WHILE THE HIGHEST POPS ARE ACROSS THE EAST IN THE AFTERNOON DID BACK OFF LIKELY TO HIGH CHANCE NUMBERS. AFTER A 6 TO 12 HOURS BREAK MODELS BRING A CLIPPER THROUGH THE AREA. THE GFS IS A BIT FASTER AT 12Z TUESDAY WITH THE MOISTURE AND SURFACE LOW SO SPLIT THE DIFFERENCE AND BROUGHT SNOW IN CLOUDS BUT ESSENTIALLY BOTH MODELS WOULD SUGGEST SNOW SOMETIME TUESDAY CONTINUING TUESDAY NIGHT. FAIRLY MILD TEMPS...COOLING OFF MID WEEK. && .LONG TERM /WEDNESDAY THROUGH FRIDAY/... SEASONAL TEMPERATURES WEDNESDAY THROUGH FRIDAY. BETTER AGREEMENT ON THE PATH OF LOW PRESSURE FROM WESTERN CANADA STAYING NORTH OF THE GREAT LAKES FOR THURSDAY. RIDGING WEDNESDAY WILL PROVIDE FOR RELATIVELY FAIR WEATHER...ALTHOUGH A FEW LIGHT SNOW SHOWERS MAY LINGER ACROSS NE OH/NW PA TO START. THE WARM FRONT EARLY THURSDAY MORNING DOES NOT HAVE A BIG PUSH OF WARM AIR WITH IT AND WILL MODERATE TEMPS ONLY TO NEAR FREEZING. AT THIS POINT IT LOOKS LIKE PRECIP ARRIVES THURSDAY NIGHT AND LINGERS INTO FRIDAY. AT THIS POINT AN EASTERN U.S. TROUGH WILL HAVE RETURNED TO END THE WEEK. && .AVIATION /12Z SATURDAY THROUGH WEDNESDAY/... LOW CONFIDENCE FORECAST CONTINUES. MOST MODEL GUIDANCE WOULD HAVE HAD US ALL IFR/MFR THROUGH THE NIGHT AND INSTEAD MOST LOCATIONS HAVE BEEN MVFR/VFR WITH THE EXCEPTION OF TOL. EARLY MORNING RUNS OF THE HRRR COME IN CLOSEST TO CURRENT REALITY SO HAVE LEANED THAT DIRECTION WITH THE FORECAST. MAIN AREA OF RAIN WILL EXIT EAST DURING THE FIRST PART OF THE MORNING. SCATTERED SHOWERS WILL REMAIN IN ITS WAKE WITH A COLD FRONT CROSSING TOL LATE MORNING...AND ERIE EARLY EVENING. FOG AND LOW STRATUS LURK TO THE WEST ACROSS NW OH AND MI/IND AHEAD OF THE COLD FRONT. HRRR DID NOT REALLY GET THIS IFR PAST THE I-71 CORRIDOR AND CLE/MFD. ALL OTHERS JUST DROP TO MVFR LATER. SLOW IMPROVEMENT OVERNIGHT...BUT REMAINING MVFR OVERCAST THROUGH 12Z SUN. PRECIPITATION CHANCES AFTER 00Z SUN VERY LIMITED AND LEFT OUT OF TAF FORECAST. SOUTHERLY WINDS WILL SHIFT SLIGHTLY TO THE SOUTHWEST AND THEN TO THE WEST LATER. GUSTS WILL DEVELOP OF 20 TO 25 KNOTS...SUBSIDING OVERNIGHT. OUTLOOK...SOME NON VFR MON THRU WED. && .MARINE... SOUTH FLOW SHIFT SOUTHWEST WITH THE PASSAGE OF A COLD FRONT. SOME COLD AIR ADVECTION MAY AID IN ALLOWING WINDS TO MIX DOWN AND YIELD GALE FORCE WINDS FOR THE EASTERN TWO THIRDS OF THE LAKE. WILL CONTINUE THE GALE WARNING THAT WAS PREVIOUSLY ISSUED FOR LATER THIS AFTERNOON AND EVENING. THIS MAY CAUSE SHIFTING/RIDGING/RAFTING OF ICE ON THE LAKE. SOUTHWEST WINDS DIMINISH FOR SUNDAY AS A RIDGE MOVES OVERHEAD. MONDAYS COLD FRONT WILL ONLY SHIFT WINDS FROM THE SOUTH TO THE SOUTHWEST. LOW PRESSURE FROM THE NORTHERN PLAINS TAKES A PATH ACROSS THE MIDWEST AND LOWER GREAT LAKES EITHER TUESDAY OR WEDNESDAY. WINDS WILL FINALLY GO NORTHWEST AFTER THE PASSAGE OF THIS SYSTEM. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...GALE WARNING FROM 4 PM THIS AFTERNOON TO 5 AM EST SUNDAY FOR LEZ061-144>149-164>169. && $$ SYNOPSIS...TK NEAR TERM...TK SHORT TERM...TK LONG TERM...OUDEMAN AVIATION...OUDEMAN MARINE...OUDEMAN
AREA FORECAST DISCUSSION
NWS PORTLAND OR
328 AM PST SAT JAN 11 2014 .SYNOPSIS...OUR STRONGEST STORM SO FAR THIS SEASON IS PUSHING A COLD FRONT ONSHORE INTO WASHINGTON AND OREGON THIS MORNING. EXPECT A PERIOD OF STRONG WINDS AND LOCALLY HEAVY RAIN THIS MORNING AS THE FRONT MOVES THROUGH...THEN MORE GUSTY WINDS AND SQUALLY SHOWERS AS THE PARENT LOW MOVES ONSHORE LATER TODAY. SNOW LEVELS WILL FALL BELOW THE CASCADE PASSES BEHIND THE COLD FRONT...RESULTING IN THE FIRST HEAVY SNOW IN QUITE SOME TIME FOR THE CASCADES. A WARM FRONT WILL FOLLOW WITH MORE RAIN SUNDAY...THEN HIGH PRESSURE WILL BRING A DRYING TREND NEXT WEEK. && .SHORT TERM...AN IMPRESSIVE COMPLEX LOW PRESSURE SYSTEM IS EVIDENT ON INFRARED SATELLITE IMAGERY WITH A CENTER NEAR 48N/135W. AN ASSOCIATED OCCLUDED FRONT WRAPS AROUND THIS SYSTEM AND INTO BRITISH COLUMBIA...WITH A STRONG ATTENDANT COLD FRONT APPROACHING MOVING ONSHORE INTO WESTERN WA AND NEAR ASTORIA THIS MOMENT. THIS COLD FRONT WILL MOVE EAST ACROSS THE DISTRICT THIS MORNING...BRINGING A PERIOD OF LOCALLY HEAVY RAIN AND STRONG WINDS...FOLLOWED BY COLDER AIR AND LOWERING SNOW LEVELS. NOT MUCH RAIN HAS FALLEN IN THE WILLAMETTE VALLEY THUS FAR AS DRY SOUTHERLY FLOW HAS DOMINATED MUCH OF THE NIGHT. THE DRYING PRODUCED BY THE SOUTHERLY FLOW HAS ALLOWED DECENT MIXING OF THE BOUNDARY LAYER DESPITE THE FACT IT IS NIGHT TIME. GUSTS HAVE ALREADY REACHED AS HIGH AS 45 MPH IN THE PORTLAND AREA. THIS WAS ENOUGH TO BRIEFLY KNOCK OUT POWER TO OUR OFFICE HERE IN PARKROSE/NE PORTLAND...AND A FEW OTHER POWER OUTAGES HAVE ALREADY BEEN REPORTED IN THE PORTLAND METRO AREA. THE WINDS HAVE BEEN QUITE A BIT STRONGER ALONG THE COAST AND IN THE COAST RANGE...ALREADY EXCEEDING OUR PREVIOUS STRONGEST WINDS OF THE SEASON FROM OUR STORM BACK IN LATE SEPTEMBER. ASTORIA AIRPORT HAS REPORTED A FEW GUSTS IN EXCESS OF 60 MPH...WITH THE HIGHEST BEING 64 MPH. THE NOAA/NOS WIND SENSOR AT GARIBALDI REPORTED 73 MPH AND AN ODOT WIND SENSOR ON THE MEGLER BRIDGE NEAR ASTORIA HAS REPORTED A PEAK GUST OF 79 MPH SO FAR. THE BIG WINNER IS THE BPA SITE ON NASELLE RIDGE IN PACIFIC COUNTY WA WITH A GUST OF 93 MPH...BUT THIS SITE IS HIGHLY ELEVATED AT 2000 FT AND EXPOSED. THIS COINCIDES NICELY WITH THE 75 KT WINDS SHOWN BY THE KLGX DOPPLER RADAR AT AROUND 2000 FT MSL. THE FIRST PEAK OF WINDS WILL COME JUST AHEAD OF THE FRONT AS IT MOVES ONSHORE EARLY THIS MORNING...WITH GUSTS 40-50 MPH POSSIBLE THROUGHOUT THE INLAND VALLEYS...GUSTS UP TO 65 MPH IN THE COASTAL COMMUNITIES...AND 70-80 MPH BEACHES AND HEADLANDS. EXPECT A BRIEF LULL AFTER THE FRONT MOVES THROUGH AS RAIN STABILIZES THE ATMOSPHERE AND PRESSURE GRADIENTS BRIEFLY SLACKEN. A SECOND SURGE OF WIND WILL COME THIS AFTERNOON AS AN IMPRESSIVE BENT-BACK OCCLUSION FEATURE PUSHES ONSHORE. THE RAP MODEL HAS BEEN DAUNTING WITH 60-70 KT WINDS HOVERING JUST 1500-2500 FT ABOVE THE VALLEY FLOOR AS THIS FEATURE MOVES ONSHORE. THE LATEST RUNS ONLY SEEM TO BE GETTING STRONGER. 00Z/06Z NAM BUFR SOUNDINGS ARE A LITTLE MORE CONSERVATIVE...WITH 55-65 KT WINDS 3000-4000 FT MSL. EITHER WAY THERE WILL BE THE POTENTIAL FOR ISOLATED GUSTS UP TO 60 MPH IN THE INTERIOR LOWLANDS TODAY...ESPECIALLY IN SQUALLY SHOWERS AND ISOLATED THUNDERSTORMS...BUT THESE SHOULD NOT BE WIDESPREAD ENOUGH TO WARRANT A HIGH WIND WARNING. IT WILL BE CLOSE THOUGH...AND CERTAINLY BEARS WATCHING. AT THIS POINT IT SEEMS LIKE A SOLID WIND ADVISORY IS THE BEST WAY TO GO FOR THE INLAND VALLEYS. THE COAST AND COAST RANGE WILL BE A DIFFERENT STORY...AND THAT IS WHY WE HAVE THE HIGH WIND WARNING IN EFFECT THROUGH THIS EVENING. EXPECT GUSTS 55-65 MPH TO IMPACT THE COASTAL COMMUNITIES AS THE LOW AND BENT-BACK OCCLUSION MOVE ONSHORE...ESPECIALLY ON THE NORTH COAST. THE GOOD NEWS IS THAT THIS SYSTEM WILL BE A FAST MOVER. THE INITIAL SHOT OF FOCUSED...HEAVY RAIN WILL PROBABLY BE TO SHORT TO CAUSE HYDRO ISSUES. THE HIGHER TERRAIN WILL SEE A QUICK INCH OF RAIN FROM THE COLD FRONT ITSELF THIS MORNING...WHILE THE VALLEYS GET 0.25-0.50 INCH. BEHIND THE FRONT...COLDER AIR WILL MOVE IN AND DROP THE SNOW LEVELS TO AROUND 3000-3500 FEET. MEANWHILE FLOW WILL TURN WESTERLY... GREAT FOR OROGRAPHICS IN THE CASCADES. THIS WILL RESULT IN A MUCH-NEEDED HEAVY SNOW EVENT IN THE CASCADES...WITH 1 TO 2 FEET OF SNOW FALLING IN THE HIGHER ELEVATIONS THIS WEEKEND. THE SNOW WILL COME WITH A SIGNIFICANT AMOUNT OF WIND...CAUSING BLOWING AND DRIFTING OF SNOW. A WARM FRONT SUNDAY WILL BRING ANOTHER SHOT OF PRECIPITATION SUNDAY. A DECENT MOISTURE PLUME WILL OVERRUN THE EXISTING COLD AIR AS A MILD UPPER LEVEL RIDGE SLOWLY BUILDS NORTHWARD OFF THE WEST COAST. THIS SHOULD RESULT IN ANOTHER SHOT OF RAIN...RANGING FROM ABOUT 0.25-0.50 INCH IN THE VALLEYS TO 1-2 INCHES IN THE HIGHER TERRAIN WITH THE HIGHEST AMOUNTS IN THE NORTH. THE WARM FRONT/BAROCLINIC ZONE WILL SLOWLY PUSH NORTH SUN/MON AS THE UPPER RIDGE BUILDS. THIS SHOULD DRY OUT THE FORECAST AREA FROM SOUTH TO NORTH...BUT STRENGTHENING INVERSIONS SHOULD ALLOW FOG TO QUICKLY DEVELOP IN THE VALLEYS. BY MON NIGHT MOST OF SW WASHINGTON AND NW OREGON SHOULD BE DRY...WITH FOG IN THE VALLEYS AND MILDER CONDITIONS UP ABOVE. WEAGLE .LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...MONDAY NIGHT THROUGH FRIDAY...KEPT A SLIGHT CHANCE FOR SOME LINGERING SHOWERS LATE MONDAY ACROSS THE NORTHERN ZONES. AFTER THIS...MODELS ARE IN GOOD AGREEMENT THAT AN UPPER LEVEL RIDGE WILL DEVELOP OVER THE REGION AND DOMINATE THE PATTERN UNTIL NEXT WEEKEND. AS A RESULT...NO PRECIP IS EXPECTED THROUGH FRIDAY EXCEPT FOR PERHAPS A LITTLE LIGHT RAIN IN SW WASHINGTON ZONES EARLY WEDNESDAY IN ASSOCIATION WITH A SHORTWAVE DISTURBANCE PROGGED TO MOVE ACROSS NORTHERN WASHINGTON. OTHERWISE EXPECT DAILY FOG TO DEVELOP ACROSS THE VALLEY LOCATIONS. THE UPPER LEVEL RIDGE WILL AMPLIFY BY THURSDAY AND OFFSHORE FLOW WILL DEVELOP INTO FRIDAY. FORECAST MODELS INDICATE THAT THE NEXT FRONTAL SYSTEM WILL ARRIVE ACROSS THE PACIFIC NORTHWEST FOR NEXT WEEKEND. TEMPERATURES WILL BE NEAR SEASONAL NORMS...WITH HIGHS GENERALLY IN THE UPPER 40S AND LOWS IN THE MID 30S THROUGH THE EXTENDED PERIOD. CULLEN && .AVIATION...FRONT NEAR THE COAST BRINGING RAIN...STRONG WINDS AT THE SURFACE AND ALOFT ALONG WITH MVFR TO IFR CONDITIONS. THE FRONT IS EXPECTED AT THE COAST AROUND 12Z AND A COUPLE OF HOURS LATER FOR THE INLAND TAF LOCATIONS. EXPECT MVFR CONDITIONS WITH THE FRONT...THEN TRENDING TO VFR BEHIND THE FRONT LATER IN THE MORNING. THERE WILL BE PLENTY OF SHOWERS AROUND THROUGH THE REST OF THE DAY INTO THE EVENING. EXPECT PERIODS OF MVFR TO DEVELOP IN SOME OF THESE SHOWERS. THE MOUNTAINS WILL BE OBSCURED THROUGH THE NEXT 24 HOURS. THE BIGGEST IMPACT FROM THIS FRONTAL SYSTEM WILL LIKELY BE VERY GUSTY WINDS AHEAD AND WITH THE FRONT. WIND SHEAR WILL LIKELY BE A CONCERN FOR MANY SITES AS A LOW LEVEL JET OF 60+ KT IS BEING ADVERTISED BY THE FCST MODELS BETWEEN 1500 AND 2000 FT. EXPECT THE GUSTY WINDS TO CONTINUE WELL INTO THE AFTERNOON. KPDX AND APPROACHES...FRONT NEAR THE COAST SHOULD MOVE ACROSS THE TERMINAL AROUND 14Z...WITH RAPID IMPROVEMENT TO VFR MID TO LATE MORNING. EXPECT PLENTY OF SHOWERS AROUND THROUGH THE REMAINDER OF THE DAY...WITH PERIODS OF MVFR DEVELOPING DURING SHOWERS. ALSO...LOOK FOR VERY GUSTY S/SW WINDS TO DEVELOP AFTER MIDNIGHT AND CONTINUE THROUGH MUCH OF THE DAY. PYLE/MH && .MARINE...THE COLD FRONT MOVED THROUGH BUOY 46089 AROUND 09Z...BUT WINDS THERE HAVE BARELY BEEN GALES. CLOSER IN THERE IS GOOD EVIDENCE OF A COASTAL JET WITH NEAR SHORE BUOYS AND BEACH WIND OBSERVATIONS INDICATING STORM FORCE GUSTS AFFECTING THE NORTHERN COASTAL WATERS AND THE COLUMBIA RIVER ENTRANCE. ON THE CENTRAL COASTAL WATERS WINDS ARE WEAKER BUT COULD SEE BRIEF STORM FORCE GUSTS AS THE FRONT MOVES THROUGH. THE FRONT IS EXPECTED TO MOVE ASHORE 4 TO 5 AM. BEHIND THE FRONT WINDS WILL VEER TO THE SOUTHWEST AND EASE. THERE COULD BE A PERIOD OF SUB GALE WINDS. HOWEVER...MODELS HAVE BEEN QUITE CONSISTENT WITH A STRONG TROUGH FOLLOWING THE FRONT MOVING INTO THE WATERS LATER IN THE MORNING FOR ANOTHER ROUND OF GALE TO STORM FORCE WIND GUSTS. ASCAT SATELLITE WINDS FROM THE 06Z PASS MATCHED UP QUITE WELL WITH THE NAM BOUNDARY LEVEL WINDS. WITH INCREASED CONFIDENCE IN THE MODELS HAVE DECIDED TO EXTEND THE STORM WARNING FOR THE NORTHERN WATERS THROUGH THE AFTERNOON...BUT LIKELY IT WILL BE OCCASIONAL GUSTS TO 45 TO 50 KT MAINLY ASSOCIATED WITH RAIN SHOWERS. ALSO HAVE LOWERED THE STORM WARNING TO GALES FOR THE CENTRAL COAST GIVEN THE TRACK THE MODELS ARE TAKING THE TROUGH. THE SEAS WILL BECOME EXTREMELY HAZARDOUS TODAY AND TONIGHT. LATEST GUIDANCE CONTINUES THE TREND OF KEEPING MAX SEAS AROUND 30 FT THIS EVENING. THE WESTERLY SWELL WILL CLIMB ABOVE 20 FT THIS MORNING PEAK NEAR 30 FT THIS EVENING...AND LIKELY DROP BELOW 20 FT SUN AFTERNOON. THIS LOOKS TO BE A DYNAMIC FETCH SITUATION AND THE MODELS MAY BE TOO QUICK TO DECAY THE OFFSHORE SEAS. MODELS ALSO TEND TO BE TOO SLOW BUILDING THE SEAS IN THESE SITUATIONS. WENT A LITTLE HIGHER ON THE MAX SEAS THAN ENP OR GWW AND DECAYED THEM A BIT MORE SLOWLY. UNFORTUNATELY THE CORE OF THE HIGHEST SWELL IS IN A DATA VOID AREA SO THERE IS NO GROUND TRUTH DATA TO PERFORM FURTHER ANALYSIS AGAINST MODEL OUTPUT IN THE OFFSHORE WATERS. SINCE THE MODELS HAVE BEEN QUITE CONSISTENT CONFIDENCE IN FORECAST IS HIGH. BY SUN WINDS AND SEAS WILL BE WINDING DOWN AS HIGH PRES BUILD TO THE SOUTHWEST OF OREGON FOR A CALMER PERIOD THROUGH MID NEXT WEEK. && .PQR WATCHES/WARNINGS/ADVISORIES... OR...WINTER STORM WARNING FROM 6 AM THIS MORNING TO 4 AM PST SUNDAY FOR CASCADES IN LANE COUNTY-NORTHERN OREGON CASCADES. WIND ADVISORY UNTIL 10 PM PST THIS EVENING FOR CENTRAL WILLAMETTE VALLEY-GREATER PORTLAND METRO AREA-LOWER COLUMBIA-SOUTH WILLAMETTE VALLEY. HIGH WIND WARNING UNTIL 10 PM PST THIS EVENING FOR CENTRAL COAST RANGE OF WESTERN OREGON-CENTRAL OREGON COAST-COAST RANGE OF NORTHWEST OREGON-NORTH OREGON COAST. HIGH SURF WARNING FROM 4 PM THIS AFTERNOON TO 10 AM PST SUNDAY FOR CENTRAL OREGON COAST-NORTH OREGON COAST. WA...WINTER STORM WARNING FROM 6 AM THIS MORNING TO 4 AM PST SUNDAY FOR SOUTH WASHINGTON CASCADES. WIND ADVISORY UNTIL 10 PM PST THIS EVENING FOR GREATER VANCOUVER AREA-I-5 CORRIDOR IN COWLITZ COUNTY. HIGH WIND WARNING UNTIL 10 PM PST THIS EVENING FOR SOUTH WASHINGTON COAST-WILLAPA HILLS. HIGH SURF WARNING FROM 4 PM THIS AFTERNOON TO 10 AM PST SUNDAY FOR SOUTH WASHINGTON COAST. PZ...STORM WARNING UNTIL 3 PM PST THIS AFTERNOON FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO CASCADE HEAD OR OUT 60 NM. GALE WARNING UNTIL 3 PM PST THIS AFTERNOON FOR COASTAL WATERS FROM CASCADE HEAD OR TO FLORENCE OR OUT 60 NM. SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL 4 AM PST SUNDAY. && MORE WEATHER INFORMATION ONLINE AT.. HTTP://WEATHER.GOV/PORTLAND INTERACT WITH US VIA SOCIAL MEDIA WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.PORTLAND.GOV WWW.TWITTER.COM/NWSPORTLAND THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
621 AM CST SAT JAN 11 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 339 AM CST SAT JAN 11 2014 MAIN FORECAST ADJUSTMENT FOR TODAY WAS TO INCREASE CLOUD COVER THIS MORNING ALONG AND EAST OF THE JAMES RIVER. AN AREA OF STRATUS ASSOCIATED WITH THE LOW LEVEL COLD AIR ADVECTION PUSH IS MOVING SOUTH INTO THE AREA. PREFER A SOLUTION CLOSER TO THE GEM REGIONAL...HRRR AND RAP...WHICH ALL SEEM TO HAVE A DECENT HANDLE ON THIS CLOUD COVER. SOME DISAGREEMENT ON HOW FAST CLOUDS MOVE OUT OF THE AREA OR DISSIPATE...BUT CONSENSUS IS THAT WE SEE RAPID CLEARING BY EARLY TO MID AFTERNOON. THUS WHILE A GOOD PORTION OF THE MORNING MAY END UP CLOUDY...WE SHOULD STILL SEE SOME SUN OVER THE ENTIRE AREA BY AFTERNOON. ADJUSTED HIGHS UP SOME IN SOUTH CENTRAL SOUTH DAKOTA WHERE MID 40S SEEM LIKELY...AND SOME IN THE DOWNSLOPE AREA EAST OF THE BUFFALO RIDGE...WHERE WE WILL LIKELY HIT OR JUST SURPASS THE FREEZING MARK. OTHERWISE THE GOING HIGHS SEEMED IN GOOD SHAPE. WINDS WILL BE BLUSTERY THIS MORNING INTO EARLY AFTERNOON AS WE MIX INTO A 20 TO 30 KT JET AT 925 MB. THE RESULT SHOULD BE A PERIOD WHERE WINDS GUST 20 TO 30 MPH...STRONGEST ALONG THE MISSOURI RIVER AND OUR FAR EASTERN CWA. THESE WINDS SHOULD THEN BEGIN TO TAPER OFF AS WE GO THROUGH THE AFTERNOON HOURS INTO THE EVENING AS THE CORE OF WINDS ALOFT PUSHES EAST AND THE SURFACE RIDGE AXIS MOVES ACROSS. LOW TEMPERATURES A BIT TRICKY TONIGHT. WE WILL LIKELY SEE A QUICK EVENING DROP IN TEMPERATURES AS WINDS LIGHTEN UP. HOWEVER SOUTHERLY WINDS WILL QUICKLY PICK BACK UP AGAIN BY MID EVENING...ENHANCING MIXING AND CAUSING A WARMING TREND THROUGH THE REST OF THE NIGHT. JUST HOW FAR WE FALL IN THE EVENING IS ALWAYS HARD TO SAY. FOR NOW WILL GO WITH LOW TO MID 20S OVER A MAJORITY OF THE AREA...WITH LOW 30S IN SOUTH CENTRAL SOUTH DAKOTA. BY 12Z...TEMPERATURES WILL HAVE RISEN INTO THE 30 TO 40 DEGREE RANGE. OTHER ISSUE TONIGHT WILL BE STRONG WINDS ALONG AND JUST EAST OF THE BUFFALO RIDGE IN SOUTHWEST MINNESOTA. 925MB WINDS SUGGEST THAT THIS AREA COULD SEE A PERIOD WHERE WINDS GUST AROUND 30 TO 40 MPH...MAINLY FROM AROUND MIDNIGHT TO 5 AM OR SO. THE REST OF US WILL SEE SUSTAINED SOUTHERLY WINDS INCREASE GENERALLY INTO THE 10 TO 20 MPH RANGE. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 339 AM CST SAT JAN 11 2014 IN THE INTERMEDIATE TERM...THE NAM APPEARS TO HAVE SOME ISSUES WITH WAVE PLACEMENT AND TIMING WHEN COMPARED TO THE GLOBAL MODELS. THEREFORE THE ECMWF AND GFS WERE FOLLOWED IN THE SUNDAY THROUGH TUESDAY NIGHT PERIODS. BASICALLY THERE ARE THREE COLD FRONTAL PASSAGES TO MONITOR...SUNDAY NIGHT AND MONDAY NIGHT...AND THE LAST ONE IN THE EXTENDED PERIOD ON WEDNESDAY NIGHT. THE GFS IS ABOUT 6 HOURS FASTER THEN THE ECMWF WITH THE FRONTAL PASSAGES SUNDAY NIGHT AND MONDAY NIGHT...AND FOR THAT MATTER ON THURSDAY NIGHT ALSO. WITH THE GFS USUALLY A BIT FAST...TRENDED MORE WITH THE ECMWF FOR FRONTAL TIMING. INITIALLY...SUNDAY STILL LOOKS LIKE A PLEASANT DAY AS SUBTLE SURFACE TROUGHING MOVES ACROSS THE FORECAST AREA. GIVEN THE 925MB TEMPERATURES OFF OF BOTH THE GFS AND ECMWF...WIDESPREAD 40S FOR HIGHS ARE WARRANTED. THIS GO AROUND...THE WEIGHTED MODEL GUIDANCE LOOKED THE BEST AS IT CAPTURED THE DOWNSLOPE FLOW ON THE EAST SIDE OF THE BUFFALO RIDGE IN SW MN...AND THE STRONGER WARMING OVER AREAS WHICH ARE EITHER FREE OF SNOW COVER OR NEARLY FREE. THE SNOW COVERED AREAS IT KEPT IN THE LOWER 40S WHICH LOOKS VERY REASONABLE AT THIS TIME. THEN THE FIRST OF THE THREE COLD FRONTS COMES DOWN SUNDAY NIGHT WHICH STILL LOOKS TO BE A DRY PASSAGE. LOWS WILL LIKELY RANGE FROM THE MID TEENS ALONG THE HIGHWAY 14 CORRIDOR...TO THE LOWER 20S IN THE MO RIVER VALLEY. 925MB WINDS ARE AVERAGING ABOUT 25 TO 35 KNOTS WHICH SUGGESTS A BREEZY NIGHT OF ABOUT 15 TO 30 MPH AT THE SURFACE. BEHIND THE COLD FRONT...MONDAY WILL BE COOLER BUT STILL ABOVE SEASONAL NORMALS. AGAIN FOLLOWING THE ECMWF TIMING CLOSER THEN THE GFS...A SURFACE TROUGH/WARM FRONT WILL MOVE INTO OUR SOUTHERN AND WESTERN ZONES BY AFTERNOON. AHEAD OF THIS TROUGH...IT IS LIKELY THAT HIGHS WILL NOT REACH 30 IN SW MN. BUT THE WESTERLY FLOW BEHIND THE TROUGH SHOULD GIVE 40 TO 45 DEGREE READINGS IN OUR SOUTH CENTRAL SD ZONES...AS WELL AS ABOUT 40 IN SIOUX CITY. THE NEXT COLD FRONT THEN SWEEPS THROUGH AFTER MONDAY EVENING. THIS FRONT HAS A LITTLE BETTER LIFT WITH IT...MORE WIND OFF THE SURFACE...A STRONG PV SURGE AND SOME BETTER MOISTURE DEPTH. HOWEVER MEASURABLE PRECIPITATION MAY BE TOUGH TO FIND...SO BELIEVE THAT ONLY LOW POPS ARE CURRENTLY WARRANTED NORTH OF SIOUX CITY AND STORM LAKE IOWA. 925MB TO 850MB TEMPERATURES SUGGEST THAT MUCH OF THE PRECIPITATION COULD BE A LIGHT MIX OF RAIN OR SNOW MONDAY EVENING...DEPENDING ON WHICH MODEL ONE BELIEVES. FOR INSTANCE THE FASTER GFS WOULD SUPPORT PRIMARILY SNOW...WHILE THE ECMWF WOULD SUGGEST LIGHT RAIN OTHER THAN IN SW MN. SO FOR NOW THIS FAR OUT... PREFERRED JUST LIGHT RAIN OR SNOW UNTIL THE SYSTEM TIMING SETTLES DOWN A BIT. THEN AFTER MIDNIGHT...ANY PRECIP LEFTOVER WILL BE ALL LIGHT SNOW. CONCERNING TEMPERATURES...THE COLD AIR PUSH IS NOT REAL SEVERE DESPITE THE DEEP PV SURGE...AND THE STRONG WINDS DO KEEP THE ATMOSPHERE FAIRLY MIXED. THEREFORE LOWS WILL BE IN THE 20S EXCEPT IN SW MN AND THE SPENCER IA AREA WHERE TEENS ARE MORE LIKELY. IT WILL BE WINDY...BUT WITH THE GFS AND ECMWF SHOWING 30 TO 40 KNOTS AT 925MB...NOT QUITE CONVINCED THAT IT WILL REACH WIND ADVISORY CRITERIA AT THIS TIME...BUT WILL CERTAINLY PUT AN ADDED CHILL TO THE AIR. ON TUESDAY...ONLY A MINIMAL RISE IN TEMPERATURES IS EXPECTED AS COLD AIR ADVECTION CONTINUES THROUGH THE DAY. HIGHS ONLY 5 TO 10 DEGREES OFF OF THE LOWS ARE LIKELY. WIND SPEEDS MAY JUST NUDGE CLOSE TO ADVISORY CRITERIA PRIMARILY IN THE MO RIVER VALLEY COUNTIES. HOWEVER AS IT WAS MONDAY NIGHT...WOULD LIKE TO SEE A LITTLE STRONGER SPEEDS AT 925MB...AS THEY ACTUALLY RELAX A BIT IN OUR WESTERN ZONES THROUGH THE AFTERNOON. WIND SPEEDS WILL KEEP WIND CHILL VALUES IN THE SINGLE DIGITS AND TEENS...MUCH WARMER THEN SOME PREVIOUS READINGS FROM DAYS GONE PAST...BUT IT WILL BE A CHILLY DAY NONETHELESS. THEN AS MENTIONED ABOVE...THE NEXT STRONG COLD FRONT PLOWS THROUGH WEDNESDAY NIGHT WITH THE STRONGEST WINDS YET. DESPITE THE TIMING DIFFERENCE...IN GENERAL BOTH THE GFS AND ECMWF ARE AVERAGING 45 TO 50 KNOTS AT 925MB LATE WEDNESDAY NIGHT AND THURSDAY...AND THAT WOULD BE CERTAINLY STRONG ENOUGH FOR WIND ADVISORY CRITERIA... POSSIBLY EVEN PUSHING HIGH WIND WARNING IN SOME OF OUR HIGHER TERRAIN AREAS. WILL DEFINITELY CONTINUE TO MENTION THIS IN THE FORTHCOMING HWO. AT THIS TIME...THIS BOUNDARY LOOKS DRY. BUT ONE THING OF NOTE IS THAT THE NEW ECMWF DOES REALLY POUR QUITE A BIT OF COLD AIR INTO OUR FORECAST AREA BY THURSDAY NIGHT AND FRIDAY. FOR EXAMPLE THE ALL BLEND IS GIVING US WIDESPREAD 20S AND 30S FOR HIGHS ON FRIDAY...WHEREAS THE RAW ECMWF HIGHS ARE SHOWING MORE LIKE SINGLE DIGITS ABOVE ZERO AND TEENS. DEFINITELY SOMETHING TO WATCH FOR BUT AT LEAST THE ECMWF HAS FAIRLY LIGHT WINDS IN OUR AREA ON FRIDAY WITH A 1036MB HIGH OVER THE FORECAST AREA. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 620 AM CST SAT JAN 11 2014 MAIN AVIATION CONCERN WILL BE LOW END MVFR OR HIGH END IFR STRATUS WORKING ITS WAY SOUTH INTO THE AREA THIS MORNING. CONFIDENCE IS LOWEST AT KSUX...BUT RAP AND HRRR HAVE PRETTY CONSISTENTLY INDICATED STRATUS SHOULD MAKE IT THERE. THUS INTRODUCED THESE CIG REDUCTIONS INTO ALL THREE TAF SITES. EXIT OF THE STRATUS IS A LOW CONFIDENCE FORECAST...BUT BELIEVE WE WILL SEE IT EXIT FROM NORTHWEST TO SOUTHEAST FROM LATE MORNING INTO EARLY AFTERNOON. FUTURE SHIFTS WILL NEED TO MONITOR TRENDS...AS THE EXPECTED TIME OF RETURN TO VFR MAY NEED TO BE ADJUSTED A FEW HOURS EITHER WAY. ONCE THE STRATUS EXITS...EXPECTING VFR CONDITIONS THROUGH THE REMAINDER OF THE PERIOD. LOW LEVEL JET INCREASES TONIGHT CREATING SOME BREEZY CONDITIONS AT THE SURFACE....GENERALLY 10 TO 20 KTS. AREAS ALONG AND JUST EAST OF THE BUFFALO RIDGE COULD SEE GUSTS TO AROUND 35 KTS. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. IA...NONE. NE...NONE. && $$ SHORT TERM...CHENARD LONG TERM...MJ AVIATION...CHENARD
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
933 AM PST SAT JAN 11 2014 .DISCUSSION...AS OF 9:33 AM PST SATURDAY...A WEAK FRONTAL SYSTEM IS CURRENTLY MOVING ACROSS THE NORTH BAY WITH WEAK ECHOES SHOWING UP ON RADAR. NO MEASURABLE RAIN HAS BEEN PICKED UP THUS FAR AT ANY AREA GAUGES. THE FRONT WILL CONTINUE TO MOVE SOUTHWARD AND SOME MEASURABLE RAIN IS EXPECTED ACROSS THE NORTH BAY THROUGH EARLY AFTERNOON. THE 12Z NAM KEEPS ALL RAIN NORTH OF THE GOLDEN GATE...ALTHOUGH SOME SPRINKLES ARE POSSIBLE AS FAR SOUTH AS THE SANTA CRUZ MOUNTAINS. SHOWERS WILL QUICKLY END BY THIS EVENING WITH FOG FORMATION POSSIBLE OVERNIGHT. HIGH PRESSURE WILL BEGIN TO BUILD ON SUNDAY BUT TEMPERATURES ARE FORECAST TO STAY IN THE LOW TO MID 60S. HIGH PRESSURE IS PROGGED TO REBUILD STRONGLY OVER THE EASTERN PACIFIC AND OVER CALIFORNIA EARLY NEXT WEEK. TEMPERATURES WILL WARM TO ABOVE NORMAL FOR THIS TIME OF YEAR WITH HIGHS IN THE 60S AND 70S. SURFACE FLOW WILL BECOME OFFSHORE BRIEFLY MONDAY AND TUESDAY WHICH WILL ENHANCE THE WARMING AND DRYING EFFECTS. AT THIS TIME WIND ADVISORIES ARE NOT EXPECTED BUT THERE COULD BE ENHANCED FIRE WEATHER CONCERNS. MEDIUM RANGE MODELS KEEP THE RIDGE IN PLACE THROUGH THE FORECAST PERIOD AND FOR THE MOST PART BEYOND THROUGH TEN DAYS. && .AVIATION...AS OF 3:30 AM PST SATURDAY...LOW CONFIDENCE AND COMPLICATED FORECAST AS A MIX OF CLOUDS COVER THE REGION WITH A FORECAST FROPA LATER TODAY. THROUGH THE MORNING HOURS...MOSTLY VFR CONDITIONS WITH MID-HIGH LEVEL CLOUDS. SPEAKING OF HIGH CLOUDS THEY ARE MAKING IT DIFF TO SEE ANY STRATUS OR FOG ON THE SATELLITE. KSTS IS STILL REPORTING FOG. WILL KEEP FOG AT KSTS THROUGH THE MORNING HOURS. FOR SF BAY...DELAYED ANY CIGS/STRATUS UNTIL ALMOST 15Z. NOT EVEN THAT CONF STRATUS WILL ACTUALLY DEVELOP. A FRONT WILL SWEEP THROUGH 18-20Z WITH POSS -RA FOR KSTS AND VCSH AROUND SF BAY AND NO RAIN MENTION S OF SF BAY. CLEAR SKIES BEHIND THE FRONT WITH POSS PATCHY FOG TONIGHT. VICINITY OF KSFO...VFR TO START THEN DEV CIGS AROUND 15Z...PT SOUNDS AND HRRR MODEL REALLY MOISTEN THE LOW LEVELS. POSS CIGS AND VCSH LATER THIS AFTERNOON WITH THE FRONTAL PASSAGE. WINDS WILL INCREASE SLIGHTLY AS WELL. VFR CONDITIONS BEHIND THE FRONT. LOW CONF. KSFO BRIDGE APPROACH...SIMILAR TO KSFO. MONTEREY BAY AREA TERMINALS...PATCHY FOG LINGERS...BUT NONE BEING REPORTED AT KSNS/KMRY. WILL KEEP AN EYE ON THIS...OTHERWISE VFR CONDITIONS. POSS CIGS LATER TODAY AS THE FRONT APPROACHES. MEDIUM CONF. && .MARINE...AS OF 3:30 AM PST SATURDAY...NO REAL CHANGE IN THE FORECAST. MODELS STILL SEEM ON TRACK TO GENERATE BUILDING NORTHWEST SWELL OVER THE COASTAL WATERS LATER TODAY.NW SWELL 14 TO 18 FEET TONIGHT/SUNDAY WITH A PERIOD OF 15-16 SECONDS. THIS WILL TRANSLATE TO LARGER SURF ALONG THE BEACHES. GIVEN THE PERIOD AND SWELL HEIGHT SQUARED SEAS SEEM PLAUSIBLE. SWELLS QUICKLY SUBSIDE SUNDAY INTO MONDAY. && .FIRE WEATHER...AS OF 3:06 AM SATURDAY...SOME LIGHT RAIN TODAY IN THE NORTH BAY BUT IN GENERAL NOT EXPECTING WIDESPREAD WETTING RAINS (GREATER THAN A TENTH). NORTHEAST WINDS WILL DEVELOP ACROSS THE NORTH AND EAST BAY HILLS LATER SUNDAY NIGHT INTO MONDAY. EVENT LOOKS MODERATE IN STRENGTH WITH 925 MB WINDS IN THE 15-30 KT RANGE. RH VALUES WILL INITIALLY REMAIN HIGH...AROUND 40% WITH MORE NOTED DRYING OCCURRING LATER MONDAY AFTERNOON INTO TUESDAY. BY TUESDAY THE COMBINATION OF RECORD WARMTH...RECORD DRY FUELS AND DRY EASTERLY FLOW WILL AT THE VERY LEAST ELEVATE FIRE DANGER AND FIRE WEATHER CONCERNS EVEN THOUGH STRICT RED FLAG CRITERIA MAY NOT BE MET. SOUTHERN CALIFORNIA MAY BE DEALING WITH A SANTA ANA AND FIRE RESOURCES AT A MINIMUM GIVEN THE TIME OF YEAR. CURRENT RH...TEMP AND WIND TRENDS BY TUESDAY LOOK EERILY SIMILAR TO WHEN THE PFEIFFER FIRE STARTED LAST MONTH IN BIG SUR. && .CLIMATE...RECORD HIGH SUMMARY FOR NEXT WEEK: CITY MON 1/13/14 TUES 1/14/14 WEDS 1/15/14 ----------------------------------------------------------------- KENTFIELD 65 IN 1994 68 IN 1924 67 IN 1945 SAN RAFAEL 68 IN 2009 68 IN 1967 73 IN 1967 NAPA 81 IN 1924 72 IN 1924 70 IN 1966 SAN FRANCISCO 72 IN 2009 69 IN 2009 73 IN 2009 SFO AIRPORT 72 IN 2009 67 IN 1948 69 IN 1974 OAKLAND DT 78 IN 2009 70 IN 2009 75 IN 2009 OAKLAND AP 69 IN 2009 65 IN 2009 74 IN 2009 RICHMOND 69 IN 2012 66 IN 1959 72 IN 2009 LIVERMORE 73 IN 2009 68 IN 2009 75 IN 1920 MOUNTAIN VIEW 71 IN 2009 73 IN 2009 72 IN 2009 SAN JOSE 75 IN 2009 73 IN 2009 73 IN 2009 GILROY 73 IN 2009 74 IN 2009 72 IN 2012 MONTEREY 77 IN 2009 76 IN 2009 76 IN 2009 SANTA CRUZ 80 IN 1948 81 IN 1975 75 IN 2009 SALINAS 84 IN 2009 80 IN 2009 79 IN 2009 KING CITY 83 IN 2009 76 IN 1981 82 IN 2009 && .MTR WATCHES/WARNINGS/ADVISORIES... .TDAY...SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM FROM 3 PM SCA...PT PINOS TO PT PIEDRAS BLANCAS 10-60 NM FROM 3 PM && $$ PUBLIC FORECAST: SIMS AVIATION: MM MARINE: MM CLIMATE: RC/RWW VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO FOLLOW US ON FACEBOOK, TWITTER, AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.SANFRANCISCOBAYAREA.GOV WWW.TWITTER.COM/NWSBAYAREA WWW.YOUTUBE.COM/NWSBAYAREA
AREA FORECAST DISCUSSION
NWS DENVER CO
ISSUED BY NATIONAL WEATHER SERVICE PUEBLO CO 1011 AM MST SAT JAN 11 2014 .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON EXCEPT 00Z MON FOR KDEN) ISSUED AT 959 AM MST SAT JAN 11 2014 3 TAF SITES...KBJC...KAPA AND KDEN ARE EXPECTED TO BE VFR NEXT 24-30 HOURS. MAIN CONCERN DURING THIS PERIOD WILL BE WINDS. IN THE NEXT 6 HOURS OR SO...LATEST GUIDANCE CONTINUES TO INDICATE THAT WINDS AT KDEN AND KAPA SHOULD REMAIN MAINLY SOUTHWESTERLY TO SOUTHERLY AT 10 TO 15 KNTS. LATEST HRRR HAS WEAK SFC LOW IN VICINITY OF DIA...SO WINDS MAY BE A BIT TRICKY LATER THIS AFTERNOON. IF ATMOS MIXES OUT...THEN DIA MAY SHIFT TO A MORE WEST- NORTHWESTERLY DIRECTION AND COULD BECOME GUSTY FOR AWHILE. KBJC WILL REMAIN GUSTY FROM THE WNW THROUGH TONIGHT. ANOTHER COLD FRONT WILL MOVE THROUGH THE AREA TOMORROW MORNING AND EXPECT GUSTY NW WINDS AT ALL TAF SITES BY LATE TOMORROW MORNING AND LASTING THROUGH THE AFTERNOON. /HODANISH && .BOU WATCHES/WARNINGS/ADVISORIES... HIGH WIND WARNING UNTIL 6 PM MST THIS EVENING FOR COZ035-036. WINTER WEATHER ADVISORY UNTIL MIDNIGHT MST TONIGHT FOR COZ031- 033-034. WINTER STORM WATCH FROM LATE TONIGHT THROUGH MONDAY MORNING FOR COZ031-033-034. && $$ AVIATION...HODANISH
AREA FORECAST DISCUSSION
NWS ALBANY NY
440 PM EST SAT JAN 11 2014 .SYNOPSIS... A STRONG COLD FRONT WILL MOVE ACROSS THE REGION THIS EVENING. RAIN WILL END FROM WEST TO EAST WITH COOLER TEMPERATURES RETURNING OVERNIGHT INTO SUNDAY. WEST TO NORTHWEST WINDS WILL INCREASE DURING SUNDAY WITH OCCASIONAL STRONGER GUSTS. A RIDGE OF HIGH PRESSURE SLIDES ACROSS SUNDAY NIGHT WITH TRANQUIL WEATHER CONDITIONS. A SOUTHERLY FLOW OF AIR ARRIVES MONDAY WITH MILD TEMPERATURES ALONG WITH AN INCREASE IN CLOUD COVER. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... FLOOD WATCH REMAINS IN EFFECT... INITIAL LINE OF EMBEDDED CONVECTION WITH CG/S PER THE NLDN WERE NOW EAST OF OUR NEW ENGLAND COUNTIES. ANOTHER LINE OF EMBEDDED CONVECTION WAS EVOLVING ACROSS EASTERN PA/WESTERN NJ INTO PORTIONS OF THE CATSKILLS. PER THE HRRR EXPERIENTIAL REFLECTIVITIES...THIS LINE MAY FILL IN A BIT MORE AS IT MOVES ACROSS THE HUDSON RIVER VALLEY FROM THE CAPITAL REGION AND POINTS SOUTHWARD. EARLIER THIS AFTERNOON...PRESSURE FALLS WERE QUITE IMPRESSIVE WITH 8-10MBS/3HRS OBSERVED IN METARS AND MSAS ANALYSIS AS A MESOLOW PROGRESSED ACROSS EASTERN NY. EXPECTATIONS ARE FOR THE COLD FRONT TO MOVE EAST OF THE NY COUNTIES AROUND 03Z SUNDAY AND WESTERN NEW ENGLAND COUNTIES AROUND 05Z SUNDAY. WE WILL TAPER OFF POPS FROM WEST TO EAST DURING THIS TIME FRAME. THEN WE SHIFT GEARS TOWARD LAKE EFFECT ACTIVITY INCREASING DOWNWIND OF LAKE ONTARIO. H850 TEMPS DROP BACK TOWARD TOWARD -6C/-7C OVERNIGHT OVER THE RELATIVELY OPEN WATERS WHERE AVERAGE WATER TEMPS WERE AROUND 3C PER THE GLERL OBSERVATIONS. THIS WOULD SUGGEST THE DELTA T/S WOULD REMAIN LESS THAN FAVORABLE EVEN WITH UPSTREAM LAKE CONNECTION FROM EITHER HURON OR GEORGIAN BAY. SO WE WILL HOLD POPS INTO THE CHC-SCT THRESHOLDS WITH A RAIN/SNOW SHOWER MIXTURE TRANSITIONING TO ALL SNOW SHOWERS OVERNIGHT. THE UPPER TROUGH TOO WILL BE APPROACHING THE REGION OVERNIGHT WHICH SHOULD KEEP CLOUDS IN PLACE AND MAINLY TERRAIN BASED CHC TO SCT RA/SN SHOWERS. OVERNIGHT LOWS PER THE MOS GUIDANCE LOOK RATHER CLOSE AND PER THE UPSTREAM OVERNIGHT LOW OBSERVATIONS...WE WILL SHADE ON THE SLIGHTLY WARMER SIDE OF THE GUIDANCE. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/... SUNDAY... UPPER TROUGH AXIS SLIDES ACROSS THE REGION IN THE MORNING WHERE CLOUDS AND SOME SHOWER ACTIVITY /MAINLY ACROSS THE TERRAIN AND NEAR LAKE ONTARIO/ WILL BE MOST PREVALENT. AS THIS UPPER TROUGH SLIDES EAST...INCREASING SUBSIDENCE AND GRADUAL IMPROVEMENTS TO THE SKY FORECAST ARE EXPECTED. HOWEVER...WITH THE INCREASE IN SOME SUNSHINE...THE MIXING LAYER HEIGHT TAPS INTO 30-40KT WINDS. FURTHERMORE...POTENTIAL FOR SOME FUNNELING DOWN THE MOHAWK MAY INCREASE THOSE MAGNITUDES. PER COLLABORATION...WE WILL HOLD OFF ON WIND ADVISORIES AT THIS TIME AS CONFIDENCE IS JUST BELOW THRESHOLDS BUT WILL MENTION IN THE HWO. PER THOSE MIXING LAYER HEIGHTS...WE WILL FAVOR HIGH TEMPERATURES INTO THE 40S FOR THE VALLEY LOCATIONS AND 30S FOR THE HIGHER TERRAIN. SUNDAY NIGHT... RIDGE AXIS SLIDES ACROSS FOR TRANQUIL CONDITIONS AND ANY LAKE RESPONSE QUICKLY DISSIPATING. AS WARMER AIR ADVECTS IN ALOFT...AND THE LOSS OF SNOW PACK...WE WILL HOLD OVERNIGHT LOWS MAINLY INTO THE MIDDLE 20S UNDER A PTCLOUDY-MOCLR SKY. MONDAY INTO MONDAY NIGHT... UPPER TROUGH AXIS MOVING INLAND ACROSS THE PACIFIC NORTHWEST WILL ADVANCE EAST ACROSS THE NORTHERN PLAINS ON MONDAY. THE DEPARTURE OF THE RIDGE AXIS AND THE APPROACH OF THIS TROUGH AXIS AND DEVELOPING COLD FRONT WILL INCREASE THE SOUTHERLY WIND FOR A RELATIVELY MILD DAY UNDER PARTIAL SUNSHINE. NCEP MODEL SUITE IS A LITTLE SLOWER SO WE WILL CONTINUE TO WITHHOLD THE MENTION OF PRECIP UNTIL MONDAY NIGHT. MOISTURE TRANSPORT IS EXPECTED/PROGGED TO INCREASE FROM THE SOUTH MONDAY EVENING WITH PRECIPITATION DEVELOPING ALONG THE FRONT. THERMAL PROFILES OFFER A MIXTURE OF RAIN/SNOW SHOWERS WITH MAINLY LIQUID TO START THEN A TRANSITION TO A WINTRY MIX OF RA/SN OVERNIGHT. MOS GUIDANCE SUGGESTS OVERNIGHT LOWS DROPPING TOWARD THE FREEZING MARK BY SUNRISE BUT WITH A LITTLE SLOWER ARRIVAL ALONG WITH CLOUD COVER AND MILDER THERMAL PROFILES...WE WILL KEEP OVERNIGHT LOWS A BIT MILDER. && .LONG TERM /TUESDAY THROUGH SATURDAY/... THE EXTENDED FORECAST PERIOD WILL INVOLVE A "WAVY" PATTERN AS SERIES OF DISTURBANCES LOOK TO ULTIMATELY CARVE OUT A TROUGH IN THE NORTHEASTERN CONUS. THE NORTHERN JETSTREAM WILL BE THE DOMINATING ONE. WHILE IT WILL BE SOMEWHAT UNSETTLED...MOISTURE WILL GENERALLY BE LIMITED WITH EACH OF THE SYSTEMS AS THEY MOVE FAIRLY QUICKLY. TEMPERATURES WILL START OFF ABOVE NORMAL BUT TREND TO A LITTLE BELOW NORMAL BY NEXT WEEKEND. ON TUESDAY...INITIAL VORTICITY FROM A DIGGING MID LATITUDE TROUGH OVER THE OHIO VALLEY...COULD SPAWN A SURFACE LOW OVER THE SOUTHEAST OR LOW MID ATLANTIC REGION. INTERESTING...THE GFS WAS THE FIRST TO REFLECT THIS IDEA...BUT HAS NOW BACKED OFF...KEEPING ANY WEAK SURFACE WAVE WELL TO THE EAST. HOWEVER SINCE THE CANADIAN/ECMWF AND WPC SOLUTIONS INDICATED IT...WE WENT WITH THE MAJORITY OF THIS SOLUTION. WHILE ALL MODELS INDICATED THE MAJORITY OF PRECIPITATION MISSES OUR REGION...IT WILL BE A CLOSE CALL...ESPECIALLY OVER OUR SOUTHEASTERN ZONES SO WILL CONTINUE WITH 30-50 POPS ON THAT DAY (HIGHEST SOUTHEAST). HIGH TEMPERATURES ON TUESDAY LOOK TO BE IN THE LOWER 30S ACROSS THE ADIRONDACKS...35 TO 40 REMAINING AREAS TO THE NORTH OF THE CAPITAL REGION AND BERKSHIRES...LOWER 40S CAPITAL REGION...MID TO UPPER 40S MID HUDSON VALLEY AND LITCHFIELD COUNTY. THIS WILL MEAN MUCH OF THE PRECIPITATION THAT WOULD FALL (ASSUMING IT WILL BE LIGHT) SHOULD BE RAIN IN THE VALLEYS...RAIN AND A WET SNOW MIX ACROSS THE HIGHER TERRAIN. TUESDAY NIGHT...LOOKS LIKE A BRIEF AREA OF SUBSIDENCE WILL OCCUR AS THE FIRST SURFACE SYSTEM DEPARTS AND ANOTHER APPROACHES FROM THE WEST. WILL KEEP SLIGHT POPS IN. OVERNIGHT LOWS WILL BE IN THE 20S. WEDNESDAY AND WEDNESDAY NIGHT....WHILE THE FIRST SURFACE LOW ASSOCIATED WITH THE UPPER LEVEL TROUGH WILL BE TO OUR EAST...ALL MODELS (EXCEPT THE CANADIAN) DEVELOP ANOTHER LOW ON WEDNESDAY NEAR OUR REGION...AS THE THE MAIN MID LEVEL TROUGH SLOWLY WORKS INTO THE REGION...WITH THE ECMWF ACTUALLY CUTTING THIS FEATURE OFF. WE INCREASE POPS UP TO 30 PERCENT AND 40 PERCENT BY WEDNESDAY NIGHT. AGAIN PRECIPITATION LOOKS LIGHT. HIGH TEMPERATURES WILL BE A LITTLE COOLER ON WEDNESDAY...AROUND 30 ACROSS THE ADIRONDACK PARK...MID OR UPPER 30S ACROSS MOST OF THE REMAINDER OF THE REGION...EXCEPT AROUND 40 IN THE MID HUDSON VALLEY AND LOWER LITCHFIELD. AGAIN...THESE TEMPERATURES WILL LIKELY MEAN ANY LIGHT PRECIPITATION WOULD FALL MAINLY AS RAIN IN THE VALLEYS...AND WET SNOW...POSSIBLY MIXED WITH A LITTLE RAIN OVER THE HIGHER TERRAIN...EXCEPT ALL SNOW ACROSS THE ADIRONDACKS. WEDNESDAY NIGHT WITH COLDER TEMPERATURES EXPECTED BACK DOWN IN THE 20S (TEENS ADIRONDACKS) ANY PRECIPITATION WOULD FALL AS SNOW OR SNOW SHOWERS. THURSDAY AND THURSDAY NIGHT...THE MID LEVEL TROUGH SHOULD BE TO OUR EAST...AND AGAIN SOME SUBSIDENCE AND POSSIBLE RIDGING LOOKS TO DRY US OUT WITH PARTIAL SUNSHINE. ONLY PLACES TO HAVE POPS ON THURSDAY WILL BE THE ELEVATED TERRAIN DUE TO POSSIBLE RESIDUAL LAKE ENHANCED UPSLOPE SHOWERS OF SNOW. TEMPERATURES LOOK TO BE SEASONABLE...WITH HIGHS RANGING FROM THE UPPER 20S ACROSS OUR NORTHWESTER AREAS...LOWER 30S CAPITAL REGION...MID OR UPPER 30S MID HUDSON VALLEY AND LOWER LITCHFIELD. OVERNIGHT LOWS WILL BE IN THE 20S. THEN ON FRIDAY...AN EVEN STRONGER DIGGING TROUGH APPROACHES WITH FROM THE GREAT LAKES...INCREASES CHANCES OF PRECIPITATION ONCE MORE. A SOUTHERLY BREEZE AHEAD OF AN APPROACHING COLD FRONT WILL BUMP TEMPERATURES BACK UP TO A LITTLE ABOVE NORMAL...RANGING FROM AROUND 30 NORTHWEST TO AROUND 40 SOUTHEAST. PRECIPITATION WILL BE IN THE FORM OF VALLEY RAIN SHOWERS...MOUNTAIN SNOW OR A RAIN SNOW MIX. ARCTIC AIR WILL FOLLOW BEHIND THIS FEATURE...LOWERING TEMPERATURES TO MAINLY THE TEENS FRIDAY NIGHT AND HOLDING THEM MAINLY IN THE 20S ON SATURDAY. ASIDE FROM SOME POSSIBLE LAKE ENHANCED SNOW SHOWERS ACROSS THE ADIRONDACKS/MOHAWK VALLEY AND SOUTHERN GREENS....OTHER AREAS LOOK DRY BUT BRISK. && .AVIATION /22Z SATURDAY THROUGH THURSDAY/... MVFR/IFR CONDITIONS WILL CONTINUE THROUGH THE EVENING PEAK AS A COLD FRONT APPROACHES FROM THE WEST...AND A MOIST SOUTHERLY FLOW WILL CONTINUES AHEAD OF THE FRONT. OCCASIONALLY...CIGS AND OR VSBYS COULD SLIP TO LIFR AS THEY HAVE AT KGFL AND KALB. WILL CONTINUE WITH LLWS ALTHOUGH OUR VAD WIND PROFILE INDICATED SLIGHTLY LESS STRONG WIND AROUND THE 2000 FOOT LEVEL (CLOSER TO 40KTS AS OPPOSED TO 60 KTS). SO FAR...THERE HAVE BEEN OFFICIALLY NO REPORTS OF LLWS IN THE PIREPS. IF THIS TREND CONTINUES...WILL REMOVE ANY LLWS WITH THE OFFICIAL EVENING ISSUANCES OF THE TAFS. ONCE THE COLD FRONT PASSES THROUGH THE REGION AFTER 00Z SUNDAY...A LEFTOVER VCSH OR -SHRA IS POSSIBLE BEHIND THE FRONT THROUGH 06Z SUNDAY. WINDS WILL SHIFT TO WESTERN TO WEST NORTHWESTERLY 5-10 KTS BEHIND THE FRONT AND IN PARTICULAR...GUSTS STILL ABOVE 20 KTS POSSIBLE ESPECIALLY AT KALB/KPSF. OTHERWISE...CONDITIONS SHOULD IMPROVE TO VFR CONDITIONS AFTER 06Z SUNDAY THROUGH THE END OF THE TAF PERIOD WITH THE END OF THE PRECIPITATION. OUTLOOK... SUNDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. MONDAY: LOW OPERATIONAL IMPACT.BREEZY NO SIG WX. MONDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA. TUESDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA. TUESDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA...SHSN. WEDNESDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...SHSN. WEDNESDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHSN. THURSDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA...SHSN. && .HYDROLOGY... THE FLOOD WATCH REMAINS IN EFFECT THROUGH SUNDAY...WITH THE PRIMARY THREAT ICE JAM FLOODING. RIVERS ARE RESPONDING TO THE RAINFALL ACROSS THE REGION WITH THE CATSKILLS BEING THE CENTER OF THE HIGHER RAINFALL TOTALS PER MESONET OBSERVATIONS. IN ADDITION...TEMPERATURES ARE QUITE MILD WITH MAINLY 50S AND NOW SOME LOWER 60S FOR THE MID HUDSON VALLEY...NW CT...BERKSHIRES...TACONICS AND WESTERN GREENS /DOWNSLOPING/. LATEST NERFC QPF SUGGESTS THE BEST QPF WILL OCCUR BEFORE 00Z WITH AROUND ONE INCH MAINLY INTO THE TERRAIN SOUTH AND EAST OF ALBANY. FURTHERMORE...ICE JAMS REMAIN THE GREATEST THREAT AS WARMER TEMPERATURES AND RAINFALL WILL ALLOW FOR ICE TO MOVE. THE NEXT SEVERAL DAYS WE WILL EXPERIENCE A DIURNAL RANGE OF ABOVE FREEZING TEMPERATURES DURING THE DAYLIGHT HOURS AND AT OR BELOW FREEZING AT NIGHT. THIS WILL LIKELY RESULT IN ICE MOVEMENT/MELTING WHICH COULD ALSO RESULT IN ISOLATED AREAS OF ICE JAMS. 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...FLOOD WATCH THROUGH SUNDAY AFTERNOON FOR CTZ001-013. NY...FLOOD WATCH THROUGH SUNDAY AFTERNOON FOR NYZ032-033-038>043- 047>054-058>061-063>066-082>084. MA...FLOOD WATCH THROUGH SUNDAY AFTERNOON FOR MAZ001-025. VT...FLOOD WATCH THROUGH SUNDAY AFTERNOON FOR VTZ013>015. && $$ SYNOPSIS...BGM NEAR TERM...BGM SHORT TERM...BGM LONG TERM...HWJIV AVIATION...HWJIV/LFM/WASULA HYDROLOGY...BGM
AREA FORECAST DISCUSSION
NWS ALBANY NY
420 PM EST SAT JAN 11 2014 .SYNOPSIS... A STRONG COLD FRONT WILL MOVE ACROSS THE REGION THIS EVENING. RAIN WILL END FROM WEST TO EAST WITH COOLER TEMPERATURES RETURNING OVERNIGHT INTO SUNDAY. WEST TO NORTHWEST WINDS WILL INCREASE DURING SUNDAY WITH OCCASIONAL STRONGER GUSTS. A RIDGE OF HIGH PRESSURE SLIDES ACROSS SUNDAY NIGHT WITH TRANQUIL WEATHER CONDITIONS. A SOUTHERLY FLOW OF AIR ARRIVES MONDAY WITH MILD TEMPERATURES ALONG WITH AN INCREASE IN CLOUD COVER. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... ...FLOOD WATCH REMAINS IN EFFECT... INITIAL LINE OF EMBEDDED CONVECTION WITH CG/S PER THE NLDN WERE NOW EAST OF OUR NEW ENGLAND COUNTIES. ANOTHER LINE OF EMBEDDED CONVECTION WAS EVOLVING ACROSS EASTERN PA/WESTERN NJ INTO PORTIONS OF THE CATSKILLS. PER THE HRRR EXPERIENTIAL REFLECTIVITIES...THIS LINE MAY FILL IN A BIT MORE AS IT MOVES ACROSS THE HUDSON RIVER VALLEY FROM THE CAPITAL REGION AND POINTS SOUTHWARD. EARLIER THIS AFTERNOON...PRESSURE FALLS WERE QUITE IMPRESSIVE WITH 8-10MBS/3HRS OBSERVED IN METARS AND MSAS ANALYSIS AS A MESOLOW PROGRESSED ACROSS EASTERN NY. EXPECTATIONS ARE FOR THE COLD FRONT TO MOVE EAST OF THE NY COUNTIES AROUND 03Z SUNDAY AND WESTERN NEW ENGLAND COUNTIES AROUND 05Z SUNDAY. WE WILL TAPER OFF POPS FROM WEST TO EAST DURING THIS TIME FRAME. THEN WE SHIFT GEARS TOWARD LAKE EFFECT ACTIVITY INCREASING DOWNWIND OF LAKE ONTARIO. H850 TEMPS DROP BACK TOWARD TOWARD -6C/-7C OVERNIGHT OVER THE RELATIVELY OPEN WATERS WHERE AVERAGE WATER TEMPS WERE AROUND 3C PER THE GLERL OBSERVATIONS. THIS WOULD SUGGEST THE DELTA T/S WOULD REMAIN LESS THAN FAVORABLE EVEN WITH UPSTREAM LAKE CONNECTION FROM EITHER HURON OR GEORGIAN BAY. SO WE WILL HOLD POPS INTO THE CHC-SCT THRESHOLDS WITH A RAIN/SNOW SHOWER MIXTURE TRANSITIONING TO ALL SNOW SHOWERS OVERNIGHT. THE UPPER TROUGH TOO WILL BE APPROACHING THE REGION OVERNIGHT WHICH SHOULD KEEP CLOUDS IN PLACE AND MAINLY TERRAIN BASED CHC TO SCT RA/SN SHOWERS. OVERNIGHT LOWS PER THE MOS GUIDANCE LOOK RATHER CLOSE AND PER THE UPSTREAM OVERNIGHT LOW OBSERVATIONS...WE WILL SHADE ON THE SLIGHTLY WARMER SIDE OF THE GUIDANCE. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/... SUNDAY... UPPER TROUGH AXIS SLIDES ACROSS THE REGION IN THE MORNING WHERE CLOUDS AND SOME SHOWER ACTIVITY /MAINLY ACROSS THE TERRAIN AND NEAR LAKE ONTARIO/ WILL BE MOST PREVALENT. AS THIS UPPER TROUGH SLIDES EAST...INCREASING SUBSIDENCE AND GRADUAL IMPROVEMENTS TO THE SKY FORECAST ARE EXPECTED. HOWEVER...WITH THE INCREASE IN SOME SUNSHINE...THE MIXING LAYER HEIGHT TAPS INTO 30-40KT WINDS. FURTHERMORE...POTENTIAL FOR SOME FUNNELING DOWN THE MOHAWK MAY INCREASE THOSE MAGNITUDES. PER COLLABORATION...WE WILL HOLD OFF ON WIND ADVISORIES AT THIS TIME AS CONFIDENCE IS JUST BELOW THRESHOLDS BUT WILL MENTION IN THE HWO. PER THOSE MIXING LAYER HEIGHTS...WE WILL FAVOR HIGH TEMPERATURES INTO THE 40S FOR THE VALLEY LOCATIONS AND 30S FOR THE HIGHER TERRAIN. SUNDAY NIGHT... RIDGE AXIS SLIDES ACROSS FOR TRANQUIL CONDITIONS AND ANY LAKE RESPONSE QUICKLY DISSIPATING. AS WARMER AIR ADVECTS IN ALOFT...AND THE LOSS OF SNOW PACK...WE WILL HOLD OVERNIGHT LOWS MAINLY INTO THE MIDDLE 20S UNDER A PTCLOUDY-MOCLR SKY. MONDAY INTO MONDAY NIGHT... UPPER TROUGH AXIS MOVING INLAND ACROSS THE PACIFIC NORTHWEST WILL ADVANCE EAST ACROSS THE NORTHERN PLAINS ON MONDAY. THE DEPARTURE OF THE RIDGE AXIS AND THE APPROACH OF THIS TROUGH AXIS AND DEVELOPING COLD FRONT WILL INCREASE THE SOUTHERLY WIND FOR A RELATIVELY MILD DAY UNDER PARTIAL SUNSHINE. NCEP MODEL SUITE IS A LITTLE SLOWER SO WE WILL CONTINUE TO WITHHOLD THE MENTION OF PRECIP UNTIL MONDAY NIGHT. MOISTURE TRANSPORT IS EXPECTED/PROGED TO INCREASE FROM THE SOUTH MONDAY EVENING WITH PRECIPITATION DEVELOPING ALONG THE FRONT. THERMAL PROFILES OFFER A MIXTURE OF RAIN/SNOW SHOWERS WITH MAINLY LIQUID TO START THEN A TRANSITION TO A WINTRY MIX OF RA/SN OVERNIGHT. MOS GUIDANCE SUGGESTS OVERNIGHT LOWS DROPPING TOWARD THE FREEZING MARK BY SUNRISE BUT WITH A LITTLE SLOWER ARRIVAL ALONG WITH CLOUD COVER AND MILDER THERMAL PROFILES...WE WILL KEEP OVERNIGHT LOWS A BIT MILDER. && .LONG TERM /TUESDAY THROUGH SATURDAY/... THE EXTENDED FORECAST PERIOD WILL INVOLVE A "WAVY" PATTERN AS SERIES OF DISTURBANCES LOOK TO ULTIMATELY CARVE OUT A TROUGH IN THE NORTHEASTERN CONUS. THE NORTHERN JETSTREAM WILL BE THE DOMINATING ONE. WHILE IT WILL BE SOMEWHAT UNSETTLED...MOISTURE WILL GENERALLY BE LIMITED WITH EACH OF THE SYSTEMS AS THEY MOVE FAIRLY QUICKLY. TEMPERATURES WILL START OFF ABOVE NORMAL BUT TREND TO A LITTLE BELOW NORMAL BY NEXT WEEKEND. ON TUESDAY...INITIAL VORTICITY FROM A DIGGING MID LATITUDE TROUGH OVER THE OHIO VALLEY...COULD SPAWN A SURFACE LOW OVER THE SOUTHEAST OR LOW MID ATLANTIC REGION. INTERESTING...THE GFS WAS THE FIRST TO REFLECT THIS IDEA...BUT HAS NOW BACKED OFF...KEEPING ANY WEAK SURFACE WAVE WELL TO THE EAST. HOWEVER SINCE THE CANADIAN/ECMWF AND WPC SOLUTIONS INDICATED IT...WE WENT WITH THE MAJORITY OF THIS SOLUTION. WHILE ALL MODELS INDICATED THE MAJORITY OF PRECIPITATION MISSES OUR REGION...IT WILL BE A CLOSE CALL...ESPECIALLY OVER OUR SOUTHEASTERN ZONES SO WILL CONTINUE WITH 30-50 POPS ON THAT DAY (HIGHEST SOUTHEAST). HIGH TEMPERATURES ON TUESDAY LOOK TO BE IN THE LOWER 30S ACROSS THE ADIRONDACKS...35 TO 40 REMAINING AREAS TO THE NORTH OF THE CAPITAL REGION AND BERKSHIRES...LOWER 40S CAPITAL REGION...MID TO UPPER 40S MID HUDSON VALLEY AND LITCHFIELD COUNTY. THIS WILL MEAN MUCH OF THE PRECIPITATION THAT WOULD FALL (ASSUMING IT WILL BE LIGHT) SHOULD BE RAIN IN THE VALLEYS...RAIN AND A WET SNOW MIX ACROSS THE HIGHER TERRAIN. TUESDAY NIGHT...LOOKS LIKE A BRIEF AREA OF SUBSIDENCE WILL OCCUR AS THE FIRST SURFACE SYSTEM DEPARTS AND ANOTHER APPROACHES FROM THE WEST. WILL KEEP SLIGHT POPS IN. OVERNIGHT LOWS WILL BE IN THE 20S. WEDNESDAY AND WEDNESDAY NIGHT....WHILE THE FIRST SURFACE LOW ASSOCIATED WITH THE UPPER LEVEL TROUGH WILL BE TO OUR EAST...ALL MODELS (EXCEPT THE CANADIAN) DEVELOP ANOTHER LOW ON WEDNESDAY NEAR OUR REGION...AS THE THE MAIN MID LEVEL TROUGH SLOWLY WORKS INTO THE REGION...WITH THE ECMWF ACTUALLY CUTTING THIS FEATURE OFF. WE INCREASE POPS UP TO 30 PERCENT AND 40 PERCENT BY WEDNESDAY NIGHT. AGAIN PRECIPITATION LOOKS LIGHT. HIGH TEMPERATURES WILL BE A LITTLE COOLER ON WEDNESDAY...AROUND 30 ACROSS THE ADIRONDACK PARK...MID OR UPPER 30S ACROSS MOST OF THE REMAINDER OF THE REGION...EXCEPT AROUND 40 IN THE MID HUDSON VALLEY AND LOWER LITCHFIELD. AGAIN...THESE TEMPERATURES WILL LIKELY MEAN ANY LIGHT PRECIPITATION WOULD FALL MAINLY AS RAIN IN THE VALLEYS...AND WET SNOW...POSSIBLY MIXED WITH A LITTLE RAIN OVER THE HIGHER TERRAIN...EXCEPT ALL SNOW ACROSS THE ADIRONDACKS. WEDNESDAY NIGHT WITH COLDER TEMPERATURES EXPECTED BACK DOWN IN THE 20S (TEENS ADIRONDACKS) ANY PRECIPITATION WOULD FALL AS SNOW OR SNOW SHOWERS. THURSDAY AND THURSDAY NIGHT...THE MID LEVEL TROUGH SHOULD BE TO OUR EAST...AND AGAIN SOME SUBSIDENCE AND POSSIBLE RIDGING LOOKS TO DRY US OUT WITH PARTIAL SUNSHINE. ONLY PLACES TO HAVE POPS ON THURSDAY WILL BE THE ELEVATED TERRAIN DUE TO POSSIBLE RESIDUAL LAKE ENHANCED UPSLOPE SHOWERS OF SNOW. TEMPERATURES LOOK TO BE SEASONABLE...WITH HIGHS RANGING FROM THE UPPER 20S ACROSS OUR NORTHWESTER AREAS...LOWER 30S CAPITAL REGION...MID OR UPPER 30S MID HUDSON VALLEY AND LOWER LITCHFIELD. OVERNIGHT LOWS WILL BE IN THE 20S. THEN ON FRIDAY...AN EVEN STRONGER DIGGING TROUGH APPROACHES WITH FROM THE GREAT LAKES...INCREASES CHANCES OF PRECIPITATION ONCE MORE. A SOUTHERLY BREEZE AHEAD OF AN APPROACHING COLD FRONT WILL BUMP TEMPERATURES BACK UP TO A LITTLE ABOVE NORMAL...RANGING FROM AROUND 30 NORTHWEST TO AROUND 40 SOUTHEAST. PRECIPITATION WILL BE IN THE FORM OF VALLEY RAIN SHOWERS...MOUNTAIN SNOW OR A RAIN SNOW MIX. ARCTIC AIR WILL FOLLOW BEHIND THIS FEATURE...LOWERING TEMPERATURES TO MAINLY THE TEENS FRIDAY NIGHT AND HOLDING THEM MAINLY IN THE 20S ON SATURDAY. ASIDE FROM SOME POSSIBLE LAKE ENHANCED SNOW SHOWERS ACROSS THE ADIRONDACKS/MOHAWK VALLEY AND SOUTHERN GREENS....OTHER AREAS LOOK DRY BUT BRISK. && .AVIATION /20Z SATURDAY THROUGH THURSDAY/... TO START THE TAF PERIOD...MVFR/IFR CONDITIONS ARE LIKELY AT ALL TAF SITES AS A WARM FRONT WILL HAVE ALREADY WORKED THROUGH THE REGION WITH SCATTERED TO NUMEROUS RAIN SHOWERS WITH GUSTY SOUTHERLY WINDS WITH GUSTS OVER 20 KTS POSSIBLE. WIND SHEAR AT 2KFT BETWEEN 55-65 KTS IS POSSIBLE THROUGH 00Z SUNDAY AS A COLD FRONT WILL MAKE ITS WAY FROM WEST TO EAST THROUGHOUT ALL THE TAF SITES. TEMPO GROUPS AT ALL TAF SITES FROM 20Z SATURDAY TO 00Z SUNDAY WITH RAIN AND WINDY CONDITIONS ALONG THE COLD FRONT PASSAGE THROUGH THE REGION. ONCE THE COLD FRONT PASSES THROUGH THE REGION AFTER 00Z SUNDAY...A LEFTOVER VCSH OR -SHRA IS POSSIBLE BEHIND THE FRONT THROUGH 06Z SUNDAY. WINDS WILL SHIFT TO WESTERN TO WEST NORTHWESTERLY 5-10 KTS BEHIND THE FRONT AND IN PARTICULAR...GUSTS STILL ABOVE 20 KTS POSSIBLE ESPECIALLY AT KALB/KPSF. OTHERWISE...CONDITIONS SHOULD IMPROVE TO VFR CONDITIONS AFTER 06Z SUNDAY THROUGH THE END OF THE TAF PERIOD WITH THE END OF THE PRECIPITATION. OUTLOOK... SUN-MON: MODERATE VFR. NO SIG WX. TUES-THUR: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...SHSN. && .HYDROLOGY... THE FLOOD WATCH REMAINS IN EFFECT THROUGH SUNDAY...WITH THE PRIMARY THREAT ICE JAM FLOODING. RIVERS ARE RESPONDING TO THE RAINFALL ACROSS THE REGION WITH THE CATSKILLS BEING THE CENTER OF THE HIGHER RAINFALL TOTALS PER MESONET OBSERVATIONS. IN ADDITION...TEMPERATURES ARE QUITE MILD WITH MAINLY 50S AND NOW SOME LOWER 60S FOR THE MID HUDSON VALLEY...NW CT...BERKSHIRES...TACONICS AND WESTERN GREENS /DOWNSLOPING/. LATEST NERFC QPF SUGGESTS THE BEST QPF WILL OCCUR BEFORE 00Z WITH AROUND ONE INCH MAINLY INTO THE TERRAIN SOUTH AND EAST OF ALBANY. FURTHERMORE...ICE JAMS REMAIN THE GREATEST THREAT AS WARMER TEMPERATURES AND RAINFALL WILL ALLOW FOR ICE TO MOVE. THE NEXT SEVERAL DAYS WE WILL EXPERIENCE A DIURNAL RANGE OF ABOVE FREEZING TEMPERATURES DURING THE DAYLIGHT HOURS AND AT OR BELOW FREEZING AT NIGHT. THIS WILL LIKELY RESULT IN ICE MOVEMENT/MELTING WHICH COULD ALSO RESULT IN ISOLATED AREAS OF ICE JAMS. 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...FLOOD WATCH THROUGH SUNDAY AFTERNOON FOR CTZ001-013. NY...FLOOD WATCH THROUGH SUNDAY AFTERNOON FOR NYZ032-033-038>043- 047>054-058>061-063>066-082>084. MA...FLOOD WATCH THROUGH SUNDAY AFTERNOON FOR MAZ001-025. VT...FLOOD WATCH THROUGH SUNDAY AFTERNOON FOR VTZ013>015. && $$ SYNOPSIS...BGM NEAR TERM...BGM SHORT TERM...BGM LONG TERM...HWJIV AVIATION...LFM/WASULA HYDROLOGY...BGM FOR THE LATEST UPDATES...PLEASE VISIT OUR WEBPAGE AT WWW.WEATHER.GOV/ALBANY
AREA FORECAST DISCUSSION
NWS ALBANY NY
1255 PM EST SAT JAN 11 2014 .SYNOPSIS... A STRONG STORM SYSTEM WILL IMPACT OUR REGION TODAY AND TONIGHT WITH MILD TEMPERATURES AND MODERATE TO HEAVY RAINFALL. THE SYSTEM`S LOW WILL MOVE ACROSS EASTERN CANADA DRAGGING ITS ASSOCIATED COLD FRONT ACROSS THE LOCAL AREA THIS EVENING. THE STEADY RAIN WILL COME TO AN END WITH THE PASSAGE OF THE FRONT. THERE WILL BE CHANCES FOR RAIN AND SNOW SHOWERS LATE TONIGHT AND SUNDAY AS A DISTURBANCE IN THE UPPER LEVELS OF THE ATMOSPHERE MOVES OVER THE REGION. IT WILL BE COOLER SUNDAY...HOWEVER TEMPERATURES WILL STILL BE ABOVE NORMAL FOR THIS TIME OF YEAR. && .NEAR TERM /THROUGH TONIGHT/... ...FLOOD WATCH REMAINS IN EFFECT... CONCERNS FOR A PERIOD OF HEAVY RAINFALL ARE ON THE INCREASE THIS AFTERNOON AS PER THE MESOSCALE OBSERVATIONS...PRESSURE FALLS ACROSS NORTHEAST PA AND REGIONAL RADAR REVEAL A MESOLOW DEVELOPING WITH AN INCREASE IN LIGHTNING ACTIVITY. METARS UPSTREAM SHOW ONE QUARTER TO ONE HALF OF AN INCH PER HOUR RAINFALL RATES. FURTHERMORE...TEMPERATURES ARE ALREADY CLOSE TO EXPECTED HIGH TEMPERATURES AND HAVE INCREASED THOSE VALUES A COUPLE OF MORE DEGREES. CROSS SECTIONS FROM THE RUC13 AND OUR VWP SHOW LOW LEVEL JET WAS ON THE INCREASE WITH VALUES CLOSE TO 60KTS JUST ABOVE 2K FEET. THIS TOO WILL ALLOW FOR THE SNOW MELT TO INCREASE ACROSS THE TERRAIN. RIVER RESPONSE WAS JUST BEGINNING AS WE CONTINUE TO CLOSELY MONITOR THE SITUATION CLOSELY. THE COLD FRONT ACROSS WESTERN NY WILL SWEEP ACROSS AREA THIS EVENING BRINGING THE STEADY RAIN TO AN END FROM WEST TO EAST. THERE WILL BE A THREAT FOR RAIN AND SNOW SHOWERS OVERNIGHT MAINLY ACROSS THE HIGHER TERRAIN AS THE UPPER TROUGH APPROACHES. && .SHORT TERM /SUNDAY THROUGH MONDAY/... THE UPPER TROUGH WILL BECOME NEGATIVELY TILTED AS IT SWINGS OVER AHEAD SUNDAY. THE MODELS KEEP THE SYSTEM PROGRESSIVE WITH RIDGING BUILDING IN AT THE SURFACE AND ALOFT IN ITS WAKE. THE RIDGE SHOULD CREST OVER THE REGION SUNDAY NIGHT QUICKLY SHIFTING OFF TO THE EAST MONDAY AS ANOTHER DEEPENING TROUGH APPROACHES. OUR REGION WILL BE UNDER BROAD SOUTHWEST FLOW BETWEEN THE DEPARTING RIDGE AND ADVANCING TROUGH WILL KEEP OUR TEMPERATURES ABOVE NORMAL. && .LONG TERM /MONDAY NIGHT THROUGH SATURDAY/... THE EXTENDED FORECAST WILL OPEN MILD WITH ABOVE NORMAL TEMPS...BUT A COOL DOWN BACK TO TYPICAL MID JANUARY WX WILL OCCUR BY THE MID WEEK IN THE WAKE OF A COLD FRONTAL PASSAGE. MONDAY NIGHT INTO TUESDAY...BETTER AGREEMENT THIS CYCLE OF THE DETERMINISTIC MEDIUM RANGE AND ENSEMBLE GUIDANCE THAT A PROGRESSIVE UPPER LEVEL PATTERN WILL IMPACT THE NORTHEAST EARLY IN THE WORK WEEK. A COLD FRONT ASSOCIATED WITH A NRN STREAM DISTURBANCE APPROACHES THE FCST AREA...WITH A SRN STREAM CYCLONE FORMING OVER THE MID ATLANTIC REGION. THIS CYCLONE WILL MOVE NORTHEAST NEAR THE MID ATLANTIC SEABOARD DURING THE AFTERNOON...BUT APPEARS TO BE FAR ENOUGH EAST BASED ON THE ECMWF FOR ONLY A MINIMAL IMPACT ON THE REGION. THE GFS IS EVEN FURTHER OUT TO SEA FOR NO IMPACT...WHILE THE CANADIAN GGEM LOOKS SIMILAR TO THE ECMWF...BUT SLIGHT SLOWER ON THE TIMING OF THE SYSTEM. THE WPC GUIDANCE FAVORS MORE A FRONTAL PASSAGE WITH THIS SYSTEM. A CHC OF RAIN OR SNOW SHOWERS WAS INCLUDED MONDAY NIGHT WITH TEMPS ABOVE NORMAL IN THE LOWER TO MID 30S. THE TIMING OF THE FRONT...AND POTENTIAL WAVE DEVELOPMENT NEAR THE COAST WILL PLAY A CRUCIAL ROLE ON HOW WARM THE SFC TEMPS GET ON TUESDAY. OUR LATEST FCST IS CLOSE TO THE WPC GUIDANCE WITH HIGHS IN THE U30S TO L40S NORTH AND WEST OF THE MOHAWK VALLEY AND UPPER HUDSON REGION WITH GENERALLY MID AND U40S TO THE SOUTH AND EAST. A CHC OF RAIN SHOWERS WAS CONTINUED DURING THE DAY. LOW LEVEL COLD ADVECTION WILL BE ONGOING DURING THE PM WITH H850 TEMPS FALLING TO -2C TO -6C OVER THE REGION. TUESDAY NIGHT INTO WEDNESDAY NIGHT...TRANSITIONAL PERIOD...WHERE SOME LIGHT SNOW OR A PERIOD OF SNOW SHOWERS MAY OCCUR ACROSS THE FCST AREA DEPENDING HOW CLOSE THE COASTAL WAVE IS LOCATED. HAVE LEANED CLOSE TO A GFS/ECMWF/WPC SCENARIO HERE WITH THE FRONT...AND WAVE DRIFTING EASTWARD OF THE REGION...BUT AN UPSTREAM CLIPPER LOW WILL APPROACH EMBEDDED IN THE H500 UPPER LEVEL TROUGH OVER THE ERN CONUS. THIS DISTURBANCE MAY BRING A PERIOD OF LIGHT SNOW AND OR SNOW SHOWERS TO ERN NY AND WRN NEW ENGLAND WED PM INTO WED NIGHT. THE EC IS A LITTLE HEAVIER ON THE QPF WITH THIS SYSTEM...AND MOVES THE SFC WAVE OVER THE SRN NY AND NEW ENGLAND BORDER. THE GFS LIFTS THE CLIPPER N/NE TOWARDS THE ST LAWRENCE RIVER VALLEY WITH LITTLE PCPN OVER THE REGION. HAVE KEPT A SLIGHT OR LOW CHC OF SNOW SHOWERS FOR THE MOST OF THE REGION. THE BEST CHC OF SOME SUSTAINED SNOWFALL LOOKS LIKE IT WILL BE EAST OF THE HUDSON RIVER VALLEY...AND THE HIGHEST CHC POPS ARE KEPT HERE WED NIGHT. LOWS TUE NIGHT WILL BE MAINLY IN THE 20S...WITH HIGHS WED CLOSER TO CLIMATOLOGICAL NORMS IN THE M20S TO L30S NORTH AND WEST OF THE CAPITAL REGION...AND MID TO U30S FROM ALY SOUTH AND EAST. LOWS WED NIGHT WILL FALL INTO THE TEENS AND 20S. THURSDAY INTO FRIDAY...A WEAK SFC RIDGE OF HIGH PRESSURE BUILDS IN BRIEFLY BEFORE ANOTHER UPPER LEVEL DISTURBANCE ASSOCIATED WITH THE H500 UPPER LEVEL LONGWAVE TROUGH APPROACHES QUICKLY FROM THE GREAT LAKES REGION FOR THU NIGHT INTO FRI WITH ANOTHER CHC OF SNOW SHOWERS. THERE IS LIMITED MOISTURE WITH THIS DISTURBANCE AT THIS TIME. IN THE WAKE OF THIS DISTURBANCE H850 TEMPS COULD TUMBLE BACK TO -17C TO -20C ACCORDING TO THE LATEST GFS BY 00Z/SAT. HIGHS BOTH DAYS WILL RANGE FROM THE U20S OVER THE SRN DACKS TO MID AND U30S FROM THE CAPITAL DISTRICT SOUTH AND EAST. && .AVIATION /18Z SATURDAY THROUGH THURSDAY/... TO START THE TAF PERIOD...MVFR/IFR CONDITIONS ARE LIKELY AT ALL TAF SITES AS A WARM FRONT WILL HAVE ALREADY WORKED THROUGH THE REGION WITH SCATTERED TO NUMEROUS RAIN SHOWERS WITH GUSTY SOUTHERLY WINDS WITH GUSTS OVER 20 KTS POSSIBLE. WIND SHEAR AT 2KFT BETWEEN 55-65 KTS IS POSSIBLE THROUGH 00Z SUNDAY AS A COLD FRONT WILL MAKE ITS WAY FROM WEST TO EAST THROUGHOUT ALL THE TAF SITES. TEMPO GROUPS AT ALL TAF SITES FROM 20Z SATURDAY TO 00Z SUNDAY WITH RAIN AND WINDY CONDITIONS ALONG THE COLD FRONT PASSAGE THROUGH THE REGION. ONCE THE COLD FRONT PASSES THROUGH THE REGION AFTER 00Z SUNDAY...A LEFTOVER VCSH OR -SHRA IS POSSIBLE BEHIND THE FRONT THROUGH 06Z SUNDAY. WINDS WILL SHIFT TO WESTERN TO WEST NORTHWESTERLY 5-10 KTS BEHIND THE FRONT AND IN PARTICULAR...GUSTS STILL ABOVE 20 KTS POSSIBLE ESPECIALLY AT KALB/KPSF. OTHERWISE...CONDITIONS SHOULD IMPROVE TO VFR CONDITIONS AFTER 06Z SUNDAY THROUGH THE END OF THE TAF PERIOD WITH THE END OF THE PRECIPITATION. OUTLOOK... SUN-MON: MODERATE VFR. NO SIG WX TUES-THUR: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...SHSN. && .HYDROLOGY... THE FLOOD WATCH REMAINS IN EFFECT FOR THIS AFTERNOON THROUGH SUNDAY...WITH THE PRIMARY THREAT ICE JAM FLOODING. A STRONG LOW PRESSURE WILL MOVE INTO SOUTHEASTERN CANADA TODAY INTO TONIGHT WITH SOME MODERATE TO HEAVY RAINFALL OCCURRING AHEAD OF A FRONTAL BOUNDARY. TEMPERATURES WILL RISE INTO THE MID 40S TO LOWER 50S AHEAD OF THE FRONT ALLOWING SNOW MELT TO OCCUR ACROSS THE REGION. RAINFALL AMOUNTS OF 3/4 TO AN INCH FROM THE CAPITAL DISTRICT NORTH AND WEST AND 1 TO 1 1/2 INCHES TO THE SOUTH AND EAST WITH LOCALLY HIGHER AMOUNTS. THE RAINFALL WILL FALL ON FROZEN GROUND WHICH WILL BECOME RUNOFF AND MAY POTENTIALLY CAUSE STREET OR POOR DRAINAGE FLOODING OF LOW LYING AREAS. THE WARM TEMPERATURES COMBINED WITH THE RAINFALL MAY CAUSE ICE MOVEMENT AND BREAK UP FOR ICE JAM FLOODING ON SOME OF THE RIVERS AND STREAMS. ICE JAM FLOODING WOULD HAVE ITS GREATEST THREAT LATE THIS AFTERNOON INTO SUNDAY. IT APPEARS THAT THE GREATEST POTENTIAL FOR FLOODING AT THIS TIME WILL INCLUDE...BUT NOT BE LIMITED TO...THE HOOSIC RIVER AT WILLIAMSTOWN AND EAGLE BRIDGE...AND THE WALLOOMSAC RIVER AT BENNINGTON. DESPITE THE PASSAGE OF THE SYSTEM...ABOVE NORMAL TEMPERATURES ARE EXPECTED TO PERSIST THROUGH EARLY NEXT WEEK. NIGHTTIME TEMPERATURES WILL FALL TO AROUND FREEZING OR BELOW. OUR NEXT BEST CHANCES FOR WIDESPREAD PRECIPITATION WILL BE TUESDAY. 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...FLOOD WATCH THROUGH SUNDAY AFTERNOON FOR CTZ001-013. NY...FLOOD WATCH THROUGH SUNDAY AFTERNOON FOR NYZ032-033-038>043- 047>054-058>061-063>066-082>084. MA...FLOOD WATCH THROUGH SUNDAY AFTERNOON FOR MAZ001-025. VT...FLOOD WATCH THROUGH SUNDAY AFTERNOON FOR VTZ013>015. && $$ SYNOPSIS...IAA NEAR TERM...IAA/BGM/11 SHORT TERM...IAA LONG TERM...WASULA AVIATION...LFM HYDROLOGY...IAA/WASULA FOR THE LATEST UPDATES...PLEASE VISIT OUR WEBPAGE AT WWW.WEATHER.GOV/ALBANY
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
400 PM EST SAT JAN 11 2014 .DISCUSSION... CURRENTLY...PREFRONTAL CONVECTIVE LINE PUSHING ACRS THE PANHANDLE TOWARD THE BIG BEND THIS AFTN. SAT PICS SHOW THE COLDEST STORM TOPS TRAILING BACK TO THE LOOP CURRENT OVER THE CENTRAL GOMEX BUT STRUGGLING TO EXPAND MUCH BEYOND A 100NM BAND AS IT APPROACHES THE NRN PENINSULA. RUC ANALYSIS SHOWING RESPECTABLE MID LVL OMEGA/UPR LVL DIVERGENCE FIELDS ACCOMPANYING THE LINE...AS WELL AS SUFFICIENT MOISTURE TO MAINTAIN THE LINE AS IT APPROACHES THE I-4 CORRIDOR. HOWEVER...VORTICITY FIELDS ARE QUITE WEAK...AS ARE THE PREFRONTAL MID LVL LAPSE RATES (GENERALLY AOB 5C/KM). TONIGHT... STORM SYSTEM CENTERED N OF THE GREAT LAKES WILL BE FED BY A 100-120KT H30-H20 JET STREAK DIGGING ACRS THE CENTRAL/NRN PLAINS AND A 120-140KT JET LIFTING OUT OF THE RIO GRANDE VALLEY. PROGRESSIVE NATURE OF THE SYSTEM WILL ERODE THE WRN FLANK OF A LARGE HI PRES RIDGE OVER THE W ATLC AND ALLOW THE SYSTEM TO CRANK A COLD FRONT THROUGH THE CENTRAL PENINSULA BY DAYBREAK. HOWEVER...DEEP MID/UPR LVL RIDGING OVER CUBA AND THE NW CARIB WILL DEFLECT THE MAJORITY OF THE SYSTEM ENERGY TO THE N AND AWAY FROM CENTRAL FL. FURTHERMORE... MORNING SOUNDINGS SHOW A SIGNIFICANT AMOUNT OF DRY AIR THRU THE H85-H60 LYR THAT WILL ERODE THE CONVECTIVE LINE AS IT PUSHES THROUGH CENTRAL FL. HIGHEST PRECIP CHANCES ACRS THE N...HOWEVER...THE LIFTING NATURE OF THE LEADING JET STREAK AND THE POSITIVE TILT OF THE TROF AXIS ARE NOT TYPICALLY CONDUCIVE TO SIG OUTBREAKS OF STRONG/SVR WX. RADAR/SAT TREND DOES NOT LEND HIGH CONFIDENCE MUCH MORE THAN A THIN LINE OF SHRAS/TSRAS WITH WIND GUSTS BTWN 35-40KTS...WILL GO WITH SCT POPS AREAWIDE...50PCT ACRS THE I-4 CORRIDOR...DECREASING TO 30PCT ARND THE NE SHORE OF LAKE OKEECHOBEE. LITTLE CHANGE TO THE MIN TEMP FCST AS TIMING OF THE FROPA WILL RESULT IN A FAIRLY WIDE SPREAD. READINGS WILL FALL INTO THE M/U50S ALONG AND N OF THE I-4 CORRIDOR DUE TO THE LONGER DURATION OF POST FRONTAL COOL AIR ADVECTION...THE TREASURE COAST WILL HOLD IN THE M/U60S AS THE CRUX OF THE COOL AIR WILL NOT HAVE MADE IT THAT FAR SOUTH BY DAYBREAK. SUNDAY... PROGRESSIVE WX PATTERN WILL PUSH THE POST FRONTAL HIGH PRES RIDGE ACRS THE DEEP SOUTH THRU THE DAY. MODERATE H100-H85 FLOW WILL RESPOND BY SHIFTING STEADILY FROM NW AT DAYBREAK...TO DUE N BY MIDDAY...TO THE E/NE BY SUNSET. SHORT DURATION OF THE NRLY FLOW WILL RETURN MAX TEMPS TO NEAR CLIMO AVG FOR EARLY JAN...U60S/L70S ALONG AND N OF I-4 AND L/M70S TREASURE COAST AND THE NE SHORE OF LAKE OKEECHOBEE. SUNDAY NIGHT THROUGH MONDAY NIGHT... SHORTWAVE RIDGE BRIEFLY BUILDS ALOFT SUNDAY NIGHT WITH FLOW QUICKLY BECOMING CYCLONIC AGAIN EARLY MONDAY AS SHORTWAVE TROUGH APPROACHES. COOLER TEMPS SUNDAY NIGHT...BUT REMAINING A FEW DEGREES ABOVE CLIMO. SURGE OF DEEPER MOISTURE FROM THE S/SW SHOULD LIFT PRECIPITABLE WATER VALUES TO 1.3-1.5 INCH RANGE BY LATE MONDAY. SOUTHERLY FLOW WILL ALLOW TEMPS TO REBOUND TO 5-10 DEGREES ABOVE CLIMO MON. MOISTURE CONVERGENCE SHOULD PROMOTE A FEW AFTERNOON SHOWERS WITH THE GREATEST CHANCE ACROSS THE NORTHERN CWA LATE IN THE DAY...WELL AHEAD OF NEXT FRONTAL BOUNDARY. TIMING/POP DIFFERENCES REMAIN IN REGARDS TO FRONTAL PASSAGE...WITH GFS FASTER/WETTER WITH SERIES OF WEAK SURFACE WAVES ALONG THE BOUNDARY...WHEREAS ECM IS CONSIDERABLY SLOWER WITH ANY SURFACE DEVELOPMENT OCCURRING INLAND ACROSS THE SE STATES...AND THEREFORE LOWER POPS LOCALLY. TRENDED TOWARD SLOWER ECM GUIDANCE...WHICH WAS ALSO CLOSER TO PREVIOUS OFFICIAL FORECAST...BUT DID RAISE POPS SLIGHTLY MONDAY NIGHT AND ADDED ISOLATED THUNDERSTORM POSSIBILITY. WARMER MINS TUE MORNING WITHIN PRE-FRONTAL SOUTHERLY FLOW. TUE-FRI... AS STRONG SHORTWAVE DIVES SOUTH FROM THE NORTHERN PLAINS TUE...LONGWAVE TROUGH AMPLIFIES/SHARPENS CONSIDERABLY FROM THE GREAT LAKES TO THE CENTRAL GULF STATES. OWING TO THE SLOWER ECM SCENARIO...TUESDAY SEEMS TO BE THE FOCUS OF BOTH MODELS FOR BRINGING PRECIP THROUGH CWA. RETURN TO NEAR NORMAL TEMPS EXPECTED TUESDAY POST FROPA...GENERALLY LOWER TO MID 70S. COOLER AND DRY WEATHER IS EXPECTED BEHIND THE FRONT INTO THE LATTER HALF OF THE WEEK WITH A REINFORCING DRY FRONT. DAYTIME HIGHS WILL BE IN THE MID-UPPER 60S WITH LOW 70S ACROSS THE TREASURE COAST AND OKEECHOBEE COUNTY. OVERNIGHT LOWS IN THE MID 40S...WITH A FEW UPPER 30S/LOW 40S IN COLDER SPOTS. MAY NEED TO TREND TEMPS DOWN FURTHER BEHIND SECONDARY FRONTAL PASSAGE WEDNESDAY NIGHT THROUGH THE END OF THE WEEK IF FUTURE MODEL RUNS SHOW CONSISTENCY WITH DEEPER AMPLITUDE OF MID/UPPER TROUGH. && .AVIATION... THRU 12/00Z...SFC WND BCMG SW WITH OCNL G22-26KT...CHC MVFR SHRAS ALL SITES THRU 12/06Z...SLGT CHC IFR TSRAS N OF KTIX-KISM AFT THRU 12/03Z. BTWN 12/06Z-12/09Z...SFC WND BCMG W/NW BTWN 8-12KTS...SLGT CHC MVFR SHRAS S OF KMLB-KLAL CONTG THRU 12/12Z. AFT 12/12Z SFC WND BCMG N/NW 8-12KTS ALL SITES. && .MARINE... TONIGHT...POOR BOATING CONDITIONS AS A COLD FRONT SWEEPS THROUGH THE THE LCL ATLC AND GENERATES A MODERATE TO FRESH SW BREEZE THAT WILL VEER STEADILY TO THE W IN THE PREDAWN HRS...THEN TO THE NW BY DAYBREAK. LCL WATERS WILL BE FETCH PROTECTED FOR MUCH OF THE NIGHT DUE TO THE OFFSHORE BREEZE...LIMITING SEA HEIGHTS TO 3-4FT NEARSHORE AND 4-6FT OFFSHORE...THOUGH SEAS UP TO 7FT OVER THE GULF STREAM ARE EXPECTED N OF SEBASTIAN INLET. MUCH OF THE WAVE ENERGY WILL BE DUE TO SHORT PD WIND CHOP. SUNDAY...PROGRESSIVE WX PATTERN WILL PUSH THE POST FRONTAL HI PRES RIDGE ACRS THE SE CONUS AND INTO THE W ATLC THRU THE PD. SFC/BNDRY LYR WINDS WILL RESPOND BY VEERING FROM NW TO NE WHILE DIMINISHING TO A GENTLE TO MODERATE BREEZE. SHORT DURATION OF THE ENHANCED WIND FIELD WILL LIMIT SEA HEIGHTS TO 3-5FT NEARSHORE AND 5-7FT OFFSHORE AROUND DAYBREAK...DECREASING TO 2-4FT NEARSHORE AND 3-5FT OFFSHORE AROUND SUNSET. SUNDAY NIGHT-MONDAY NIGHT...ONSHORE FLOW AOB 15 KT WILL VEER FROM EAST TO SOUTH/SOUTHWEST WELL IN ADVANCE OF FRONTAL TROUGH. TUE-WED...WINDS COME AROUND TO THE SOUTHEAST 5-10KTS ON MONDAY AS THE HIGH DEPARTS QUICKLY OFF TO THE EAST. INCREASING SOUTHERLY FLOW EXPECTED MONDAY NIGHT AHEAD OF THE NEXT FRONT. SOME TIMING DIFFERENCE BETWEEN MODELS...BUT APPEARS THAT THE ACTUAL WIND SHIFT WILL HOLD OFF UNTIL TUESDAY NIGHT...LEAVING WEST-SOUTHWEST WINDS 15KTS DURING THE DAY ON TUESDAY BECOMING NORTHWEST TUES EVE AND NIGHT. SECONDARY FRONTAL BOUNDARY MOVES JUST NORTH OF THE WATERS ON WED...BACK WINDS TO THE WEST ON WED WITH THE TIGHTENING GRADIENT BRINGING WINDS UP TO 20KTS. LIGHT WINDS WILL KEEP SEAS 2-4FT ON MONDAY...THOUGH THE STRONGER OFFSHORE COMPONENT INTO TUES WILL BUILD SEAS UP TO 6FT WELL OFFSHORE NORTH OF THE CAPE BY LATE TUE INTO WED. SEAS GENERALLY 2-3 FT NEARSHORE AND 3-5 FT OFFSHORE SUNDAY NIGHT/MONDAY...WILL BUILD TO 3-4 FT NEARSHORE AND 3-6 FEET OFFSHORE MONDAY NIGHT. ISOLATED SHOWERS SUNDAY NIGHT BECOME SCATTERED MONDAY AND MONDAY NIGHT. && .FIRE WEATHER... COLD FROPA TONIGHT WILL FORCE SFC/TRANSPORT WINDS TO VEER TO NW TONIGHT...FOLLOWED BY A POST FRONTAL HIGH PRES RIDGE ON SUN THAT WILL PUSH WINDS TO THE N/NE. A BRIEF BUT STRONG PERIOD OF DRY AIR ADVECTION WILL ALLOW MIN RH VALUES TO FALL TO 30-35PCT FOR 4-6HRS ACRS THE INTERIOR N OF LAKE KISSIMMEE/LAKE MARIAN. HOWEVER...ERC NUMBERS ARE LOW ENOUGH DUE TO RECENT PRECIP EVENTS THAT OVERALL FIRE THREAT WILL REMAIN LOW. && .PRELIMINARY POINT TEMPS/POPS... DAB 58 66 49 77 / 50 0 10 30 MCO 60 71 50 79 / 50 0 10 20 MLB 63 70 55 79 / 40 0 10 20 VRB 65 71 55 80 / 30 10 10 20 LEE 56 69 49 77 / 50 0 10 30 SFB 59 70 51 78 / 50 0 10 20 ORL 60 71 52 78 / 50 0 10 20 FPR 66 72 55 80 / 30 10 10 20 && .MLB WATCHES/WARNINGS/ADVISORIES... FL...LAKE WIND ADVISORY UNTIL 6 PM EST THIS EVENING FOR COASTAL VOLUSIA-INLAND VOLUSIA-NORTHERN BREVARD-NORTHERN LAKE- ORANGE-OSCEOLA-SEMINOLE-SOUTHERN BREVARD-SOUTHERN LAKE. AM...SMALL CRAFT ADVISORY UNTIL 10 AM EST SUNDAY FOR WATERS FROM FLAGLER BEACH TO VOLUSIA BREVARD COUNTY LINE 20 TO 60 NM OFFSHORE-WATERS FROM SEBASTIAN INLET TO JUPITER INLET 20 TO 60 NM OFFSHORE-WATERS FROM VOLUSIA BREVARD COUNTY LINE TO SEBASTIAN INLET 20 TO 60 NM OFFSHORE. && $$ SHORT TERM/AVIATION...BRAGAW LONG TERM/IMPACT WX...SPRATT
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
300 PM EST SAT JAN 11 2014 .SYNOPSIS... 19Z WATER VAPOR AND H4 RAP ANALYSIS SHOW A HIGHLY AMPLIFIED UPPER LEVEL PATTERN IN PLACE ACROSS THE CONUS. MAIN PLAYER FOR OUR FORECAST THE NEXT 18-24 HOURS WILL IS A DEEP AND SHARP LONGWAVE TROUGH EJECTING EASTWARD FROM THE CENTRAL PLAINS INTO THE EASTERN STATES. THE BASE OF THIS TROUGH EXTENDS SOUTHWARD TO THE NORTHERN GULF COAST AND WILL PIVOT INTO THE SOUTHEASTERN STATES THROUGH THE EVENING AND OVERNIGHT HOURS. THIS TROUGH IS "BOOKENDED" BY LONGWAVE RIDGES OVER BOTH THE INTER-MOUNTAIN WEST AND NOW EXITING OFF THE ATLANTIC SEABOARD. AT THE SURFACE...HIGH PRESSURE RIDGE IS BEING SHOVED SOUTH AND EAST OUT OF THE PENINSULA IN RESPONSE TO THE APPROACH OF A SURFACE COLD FRONT AHEAD OF THE UPPER TROUGH. THIS FRONT CURRENTLY EXTENDS DOWN FROM NORTHERN GEORGIA TO THE FLORIDA PANHANDLE AND NORTHEAST GULF OF MEXICO. SOUTHERLY FLOW AHEAD OF THE FRONT IS BRINGING WITH IT A WARM AND HUMID BOUNDARY LAYER. THIS HIGH DEWPOINT AIR OVER THE NOW COOL SHELF WATERS OF THE EASTERN AND NORTHEASTERN GULF OF MEXICO IS RESULTING IN AREAS/WIDESPREAD SEA FOG (SOME VERY DENSE) OVER THE COASTAL WATERS. THE FOG IS MOST PREVALENT TO THE NORTH OF SARASOTA AND CONDITION WILL REMAIN FAVORABLE FOR THE REDUCED VISIBILITIES THROUGH AT LEAST THE EARLY EVENING UNTIL THE COLD FRONT CAN PASS AND CLEAR THE MORE HUMID AIRMASS AWAY. GENERALLY SPEAKING WE LOOK FOR DEWPOINTS TO BE 3-5+ DEGREES WARMER THAN THE SURFACE WATER TEMPERATURES FOR A SIGNIFICANT THREAT OF SEA FOG. AFTER LAST WEEKS "COLD SNAP"...THE SHELF WATERS COOLED OFF CONSIDERABLY AND HAVE ALLOWED THESE CONDITIONS TO BE MET. A MARINE DENSE FOG ADVISORY IS IN EFFECT TO THE NORTH OF ENGLEWOOD THROUGH THE MIDDLE EVENING AND MULTIPLE REPORTS OF VISIBILITY NEAR ZERO HAVE BEEN RECEIVED THROUGH THE DAY FROM AREAS TO THE WEST OF EGMONT KEY. && .SHORT TERM (REST OF TODAY THROUGH MONDAY NIGHT)... AS MENTIONED ABOVE...THE UPPER TROUGH WILL PIVOT EASTWARD AND FORCE THE COLD FRONT THROUGH THE AREA TONIGHT. LOW/MID LEVEL WAA ALONG WITH DEEP SYNOPTIC FORCING/DCVA/QV CONVERGENCE AHEAD OF THE TROUGH AXIS ARE SUPPORTING A SOLID MCS CLUSTER OF SHOWERS/STORMS FROM GA TO THE NORTHEAST GULF THIS AFTERNOON. THIS FORCING ALONG WITH A FAVORABLE RRQ JET PLACEMENT WILL SHIFT EASTWARD WITH TIME INCREASING THE CHANCES FOR SHOWERS AND A FEW STORMS TO OUR ZONES NORTH OF TAMPA BAY BY THE LATE AFTERNOON HOURS/EARLY EVENING HOURS. THE BEST CHANCES FOR RAIN BEFORE SUNSET WILL BE FOR THESE NORTHERN ZONES. ELSEWHERE...THE SYNOPTIC FORCING WILL NOT ARRIVE DURING THE DAYLIGHT HOURS...BUT AN INCREASINGLY UNSTABLE ENVIRONMENT MAY STILL ALLOW FOR A FEW SCT SHOWERS TO DEVELOP ACROSS THE INTERIOR PENINSULA. SOME OF THE MORE RELIABLE HIGH-RES GUIDANCE MEMBERS SUCH AS THE HRRR CONTINUE TO HINT AT THIS POSSIBILITY...BUT DO TO THE LACK OF ACTIVITY THUS FAR WILL DECREASE THE POPS TO 20% FOR THESE SOUTH-CENTRAL INLAND ZONES. DURING THE EVENING HOURS THE BEST SYNOPTIC FORCING ARRIVES OVER THE NORTHERN PENINSULA ALONG WITH THE COLD FRONT/PRE-FRONTAL TROUGH FOR LOW LEVEL FOCUS. THE CHANCES FOR A BAND OF SHOWERS AND STORM IS FAIRLY HIGH AND HENCE SO ARE THE POPS. THE STORM PREDICTION CENTER HAS OUTLOOKED CITRUS AND LEVY COUNTY FOR A SLIGHT RISK OF SEVERE WEATHER THIS EVENING. WHILE IT IS NOT COMPLETELY OUT OF THE QUESTION FOR A FEW STRONGER STORMS...THE LOW LEVEL JET IS QUITE LIMITED THIS FAR SOUTH AND WILL BE STARTING TO EXIT THE AREA. ALSO...HIGHLY QUESTIONABLE IF ANY OF THESE STORMS WILL BE TRULY ROOTED AT THE SURFACE WITH THE FLOW DEVELOPING OFF THE COOLER SHELF WATERS. MORE LIKELY THAT ANY STORMS WILL BE AT LEAST PARTIALLY ELEVATED WHICH WILL FURTHER LIMIT THE WIND THREAT. THIS DOES NOT MEAN THAT BRIEF HEAVY RAIN AND LIGHTNING MAY NOT BE A THREAT WITH ANY STRONGER CELLS SINCE THE OVERALL FORCING FOR ASCENT IS QUITE STRONG. DESPITE THE LIMITING FACTORS...WE WILL CONTINUE TO MONITOR THE LOW LEVEL ENVIRONMENT IN CASE CONDITIONS BECOME MORE FAVORABLE FOR SURFACE BASED PARCELS OVER THE NORTHERN NATURE COAST AS THE DAY PROGRESSES. THE COLD FRONT AND ASSOCIATED CLUSTERS OF SHOWERS/ISOLATED STORMS WILL SHIFT SOUTH AND EAST ACROSS THE AREA THIS EVENING AND BE MAINLY SOUTH OF TAMPA BAY BY THE SECOND HALF OF THE NIGHT. THE CONVECTION WILL ALSO BECOME LESS ORGANIZED AND LIKELY MORE BROKEN WITH TIME AS THE UPPER LEVEL FORCING AND JET DYNAMICS PIVOTS AWAY FROM THE REGION. JUST HAVE CHANCE POPS FOR SHOWERS TO THE SOUTH OF TAMPA BAY AFTER MIDNIGHT AND END ALL RAIN DOWN TO EVEN FORT MYERS BY SUNRISE ON SUNDAY. SUNDAY...A DRIER AIRMASS ALONG WITH SEASONABLE TEMPERATURES AND CLEARING SKIES WILL FILL THE REMAINDER OF THE WEEKEND AS HEIGHTS RISE ALOFT OF THE PENINSULA...AND SURFACE HIGH PRESSURE SLIDES EASTWARD INTO THE REGION FROM THE EASTERN GULF. SUNDAY NIGHT... THE ONE "COOLER" NIGHT BEHIND THIS FRONT. AT THIS TIME WE ARE NOT EXPECTING A THREAT FOR FREEZING TEMPERATURES FOR EVEN OUR MOST NORTHERN ZONES...ALTHOUGH WITH THE HIGH IN CLOSE PROXIMITY AND GENERALLY CLEAR SKIES...SOME PATCHY FROST IS NOT OUT OF THE QUESTION LATE AT NIGHT FOR THE COLDEST RADIATIONAL COOLING SPOTS UP TOWARD LEVY COUNTY. OTHERWISE LOOKING FOR LOW TO RANGE FROM THE LOW TO MID 40S NORTH...TO THE UPPER 40S/MIDDLE 50S SOUTH. MONDAY AND MONDAY NIGHT... THE NEXT LONGWAVE TROUGH (POTENTIAL WEATHER MAKER) BEGINS TO DIG THROUGH THE CENTRAL CONUS AND APPROACH OUR REGION LATER MONDAY AND MONDAY NIGHT. GFS/ECMWF DO NOT FULLY AGREE ON THE DETAILS...BUT DO AGREE ON AT LEAST SOME LOBE OF SHORTWAVE ENERGY ROUNDING THE BASE OF THIS TROUGH AND RESULTING IN A WEAK WAVE OF LOW PRESSURE MOVING ALONG THE NORTHERN GULF COAST. THE COLD FRONT TRAILING BACK FROM THIS FEATURE LOOKS TO APPROACH OUR ZONES MONDAY NIGHT OR TUESDAY MORNING. FOR NOW HAVE FAVORED THE MORE NORTHWARD LOW TRACK IN CLOSER PROXIMITY TO THE TRUE NORTHERN GULF SST BAROCLINIC ZONE...AND LATER FRONTAL ARRIVAL OF THE ECMWF. THIS SOLUTION KEEP US A BIT WARMER AND RESULTS IN AN ARRIVAL TIME OF ANY ORGANIZED SHOWERS HOLDING OFF UNTIL MONDAY NIGHT OR TUESDAY MORNING AS WELL. && .LONG TERM (TUESDAY THROUGH NEXT SATURDAY)... MODELS ARE IN RELATIVELY GOOD AGREEMENT THROUGH THE EXTENDED PERIODS...WITH JUST SOME MINOR DISCONTINUITIES. THE FIRST REVOLVES AROUND A COLD FRONT PASSAGE IN THE MONDAY NIGHT/TUESDAY TIME FRAME...WHERE THE GFS IS FASTER THEN THE NAM/ECMWF/CANADIAN...SO WILL LEAN THE FORECAST TOWARD THE MODEL CONSENSUS AND SLOWER SOLUTION. THE OTHER DISCONTINUITY RESIDES AROUND THE AMPLITUDE OF THE UPPER TROUGH DIGGING INTO THE SOUTHEAST CONUS WEDNESDAY AND WEDNESDAY NIGHT WHICH HAS AN IMPACT ON THE STRENGTH OF COLD AIR ADVECTION PUSHING SOUTHWARD THROUGH THE PENINSULA. THE CANADIAN/ECMWF ARE IN GOOD AGREEMENT WITH THE AMPLITUDE OF THE TROUGH WHILE THE GFS IS NOT QUITE AS STRONG. AS A RESULT...WILL LEAN THE FORECAST MID WEEK TOWARD THE CANADIAN/ECMWF SOLUTION. BY LATE NEXT WEEK MODEL SOLUTIONS SHOW HIGH PRESSURE BUILDING BACK INTO THE REGION ON THURSDAY WITH YET ANOTHER RE-ENFORCING COLD FRONT MOVING THROUGH THE AREA FRIDAY NIGHT. THERE IS SOME DISAGREEMENT ON THE DEGREE OF COLD AIR ADVECTION ONCE AGAIN...BUT GIVEN THAT THERE IS QUITE SOME TIME BETWEEN NOW AND NEXT WEEKEND...WILL JUST TAKE A BLENDED APPROACH TO LIMIT POTENTIAL FORECAST ERROR. AS FOR FORECAST DETAILS...WILL CARRY RAIN CHANCES IN THE FORECAST WITH THE INITIAL COLD FRONT MONDAY NIGHT AND TUESDAY. AFTER THAT...THE NEXT COUPLE FRONTAL PASSAGES WILL LACK ANY SIGNIFICANT RETURN FLOW MOISTURE FROM THE GULF OF MEXICO...SO EXPECT THAT RAIN FREE CONDITIONS WILL PREVAIL TUESDAY NIGHT THROUGH NEXT SATURDAY. AS FOR TEMPERATURES...EXPECT HIGHS CLOSE TO NORMAL ON TUESDAY BEFORE DROPPING TO BELOW NORMAL LEVELS THROUGH THE REMAINDER OF THE WEEK AND INTO NEXT WEEKEND. && .AVIATION... 11/18Z-12/18Z...GUSTY WINDS WITH GENERALLY VFR CLOUDS BUT LCL MVFR CIG REST OF THIS AFTERNOON. CONDITIONS THEN DETERIORATE FOR THE OVER NIGHT HOURS WITH MVFR CIGS...POSSIBLE SEA FOG DRIFTING ACROSS THE NORTHERN COASTAL TERMINALS...AND VCNTY SHRA EXCEPT VCNTY TSRA EARLY IN THE PERIOD FROM KSRQ NORTHWARD. DRY AIR FILTERS IN JUST AFTER DAY BREAK WITH CLEARING AND NORTHERLY WINDS. && .MARINE... A COLD FRONT WILL CROSS THE FORECAST WATERS FROM NORTHWEST TO SOUTHEAST TONIGHT ALONG WITH A BAND OF SHOWERS AND ISOLATED STORMS. MODERATE SOUTHWEST WINDS AHEAD OF THE FRONT WILL SHIFT NORTHWEST IN ITS WAKE AND BRIEFLY REACH CAUTIONARY LEVELS BEFORE DROPPING BACK BELOW HEADLINE CRITERIA SUNDAY MORNING. HIGH PRESSURE WILL THEN BE IN CONTROL OF THE EASTERN GULF OF MEXICO THROUGH AT LEAST MONDAY MORNING BEFORE THE NEXT COLD FRONT APPROACHES MONDAY NIGHT OR TUESDAY. AREAS OF DENSE MARINE FOG TO THE NORTH OF SARASOTA WILL CONTINUE TO BE AN ISSUE UNTIL THE PASSAGE OF THE COLD FRONT LATER THIS EVENING ENDS THE THREAT FOR REDUCED VISIBILITY. && .FIRE WEATHER. A COLD FRONT WILL CROSS THE REGION OVERNIGHT WITH A BAND OF SHOWERS AND STORMS AND USHER IN A COOLER AND MUCH DRIER AIRMASS FOR SUNDAY. RELATIVE HUMIDITY VALUES ARE FORECAST TO DROP BELOW 35 PERCENT FOR MUCH OF THE REGION SUNDAY AFTERNOON...HOWEVER WITH LIGHT WINDS AND LOW ERC VALUES...NO RED FLAG CONDITIONS ARE ANTICIPATED. ENOUGH MOISTURE RETURN WILL REACH THE AREA BY MONDAY TO PREVENT ANY CRITICALLY LOW RELATIVE HUMIDITY. FOG POTENTIAL...AREAS OF DENSE FOG ARE EXPECTED ALONG THE COAST FROM PINELLAS COUNTY NORTHWARD THIS EVENING WITH THE FOG LIFTING AS A COLD FRONT CROSSES THE AREA OVERNIGHT. && .PRELIMINARY POINT TEMPS/POPS... TPA 59 71 52 73 / 60 0 0 10 FMY 65 76 55 79 / 40 0 0 10 GIF 58 73 50 77 / 60 0 0 10 SRQ 61 71 53 75 / 60 0 0 10 BKV 55 70 43 75 / 60 0 0 10 SPG 61 69 54 74 / 60 0 0 10 && .TBW WATCHES/WARNINGS/ADVISORIES... FL...LAKE WIND ADVISORY UNTIL 6 PM EST THIS EVENING FOR COASTAL CHARLOTTE-COASTAL CITRUS-COASTAL HERNANDO-COASTAL HILLSBOROUGH-COASTAL LEE-COASTAL LEVY-COASTAL MANATEE- COASTAL PASCO-COASTAL SARASOTA-DESOTO-HARDEE- HIGHLANDS-INLAND CHARLOTTE-INLAND CITRUS-INLAND HERNANDO-INLAND HILLSBOROUGH-INLAND LEE-INLAND LEVY- INLAND MANATEE-INLAND PASCO-INLAND SARASOTA-PINELLAS- POLK-SUMTER. GULF WATERS...DENSE FOG ADVISORY UNTIL 10 PM EST THIS EVENING FOR ENGLEWOOD TO TARPON SPRINGS OUT 20 NM-ENGLEWOOD TO TARPON SPRINGS OUT 20 TO 60 NM-TARPON SPRINGS TO SUWANNEE RIVER OUT 20 NM-TARPON SPRINGS TO SUWANNEE RIVER OUT 20 TO 60 NM. && $$ SYNOPSIS/SHORT TERM/MARINE/FIRE WX...MROCZKA LONG TERM...JELSEMA AVIATION...RUDE
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
1122 AM EST SAT JAN 11 2014 .SYNOPSIS... A COLD FRONT WILL MOVE THROUGH THE FORECAST AREA THIS AFTERNOON. HIGH PRESSURE BEHIND THE FRONT WILL BE OVER OUR REGION SUNDAY. THE HIGH WILL MOVE OFF THE COAST SUNDAY NIGHT. ANOTHER COLD FRONT WILL MOVE INTO THE AREA MONDAY NIGHT. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... HIGH MOISTURE ASSOCIATED WITH THE STRONG H85 JET AND LIFT WITH THE RIGHT ENTRANCE REGION OF THE H25 JET PLUS CONVERGENCE ALONG THE COLD FRONT SUPPORT CATEGORICAL POPS THIS AFTERNOON. THE NAM AND GFS PLUS SREF MEAN INDICATED GENERAL RAINFALL TOTALS AROUND 0.7 OF AN INCH...BUT WITH PRECIPITABLE WATER NEAR 1.6 OF AN INCH HEAVIER AMOUNTS WILL LIKELY OCCUR IN SOME LOCATIONS. THE NAM DISPLAYS SURFACE-BASED LI/S LOWERING TO -1 TO -2 THIS AFTERNOON. SATELLITE LOOP ALSO SHOWS SOME HOLES IN THE CLOUDS ACROSS THE ERN PORTION OF THE CWA. THIS COULD INCREASE THE INSTABILITY THREAT FOR AREAS MAINLY ACROSS THE ERN MIDLANDS...EAST OF COLUMBIA. THE NAM AND GFS HAVE H85 WINDS NEAR 60 KNOTS. THE MAIN THREAT IS DAMAGING STRAIGHT-LINE WINDS BUT FORECAST HODOGRAPHS ALSO SUPPORT POSSIBLE TORNADOES. 06Z HRRR INDICATES THE MAIN CONVECTIVE LINE WILL BE IN THE FORECAST AREA DURING THE NOON TO 500 PM TIME FRAME. && .SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/... DRYING WILL OCCUR BEHIND THE FRONT TONIGHT. THE SHOWER CHANCE WILL DECREASE RAPIDLY FROM WEST TO EAST DURING THE EVENING. HIGH PRESSURE WILL BE OVER THE FORECAST AREA SUNDAY. THE HIGH WILL MOVE OFF THE COAST SUNDAY NIGHT. THE TEMPERATURE GUIDANCE WAS CONSISTENT. TEMPERATURES WILL BE ABOVE NORMAL. && .LONG TERM /MONDAY NIGHT THROUGH FRIDAY/... THE GFS AND ECMWF DISPLAY MOISTURE ASSOCIATED WITH A COLD FRONT MONDAY NIGHT INTO TUESDAY. THE ECMWF CONTINUES TO INDICATE MORE MOISTURE COMPARED TO THE GFS. CONTINUED CHANCE POPS BECAUSE OF THE MODEL INCONSISTENCY. EXPECT A REINFORCING COLD FRONT WITH LIMITED MOISTURE WEDNESDAY. THE MODELS SHOW DRY RIDGING DOMINATING THURSDAY WITH YET ANOTHER COLD FRONT WILL LITTLE MOISTURE FRIDAY. ABOVE NORMAL TEMPERATURES SHOULD OCCUR AHEAD OF THE FRONT TUESDAY...WITH COOLING TO NEAR OR SLIGHTLY BELOW NORMAL BY THURSDAY. && .AVIATION /16Z SATURDAY THROUGH WEDNESDAY/... RESTRICTIONS DOMINATING THROUGH 12/00Z THEN CONDITIONS IMPROVING. COLD FRONT CONTINUES TO MARCH ACROSS THE SOUTHEAST WITH WSR-88D NETWORK SHOWING SHOWERS AND A FEW THUNDERSTORMS MOVING THROUGH EASTERN GA TOWARD AGS/DNL. WINDS HAVE ALREADY INCREASED AT THE TAF SITES WITH FURTHER INCREASES OVER THE NEXT COUPLE OF HOURS TO AROUND 15 KNOTS WITH GUSTS TO 25 KNOTS BY 16-18Z AT ALL SITES. LIFR AND IFR CONDITIONS EARLIER THIS MORNING HAVE IMPROVED TO MVFR IN MANY AREAS. LATER THIS MORNING AND INTO THE AFTERNOON THUNDERSTORMS REMAIN THE CONCERN...THE BEST CHANCE APPEARS TO BE BETWEEN 17-21Z. WITH THUNDERSTORMS WHICH DEVELOP THE POTENTIAL EXISTS FOR STRONG AND GUSTY WINDS. WIND SHEAR WILL ALSO BE A CONCERN AS LOW LEVEL WINDS WILL BE AROUND 45-50 KNOTS THROUGH THE AFTERNOON. HAVE INCLUDED WIND SHEAR FOR ALL TAF SITES THROUGH THE AFTERNOON. FRONT WILL MOVE OFFSHORE THIS EVENING WITH DRIER AIR BEGINNING TO MOVE IN WITH CONDITIONS RETURNING TO VFR BY 12/01Z AT CAE/CUB/AGS/DNL AND 12/02Z OGB. EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE MONDAY NIGHT THROUGH TUESDAY MORNING IN SHOWERS ASSOCIATED WITH THE NEXT COLD FRONT. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...NONE. GA...NONE. && $$ 77
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
426 PM CST SAT JAN 11 2014 .DISCUSSION... 306 PM CST LOOKING AHEAD TO THE COMING WEEK...THE FIRST THING THAT BECOMES APPARENT IS HOW CHALLENGING THE TEMPERATURE FORECASTS MIGHT BE...WITH MULTIPLE POTENTIAL PERIODS OF NON DIURNAL TRENDS. THE BEST CHANCE OF MORE SNOW APPEARS TO BE MONDAY NIGHT INTO TUESDAY. SUNDAY SUNDAY AFTERNOON LOOKS PRETTY STRAIGHTFORWARD WITH PRONOUNCED WARM ADVECTION ON SOUTH TO SOUTHWEST WINDS DEVELOPING UNDER A 50 TO 60 KT JET AT 850 MB. LATEST VIS SATELLITE IMAGERY SUGGESTS DOWNSTATE ILLINOIS HAS LOST MUCH OF ITS SNOWPACK...WHICH WOULD FURTHER AID IN THE POTENTIAL WARMING OR AT LEAST NOT HINDER THE EFFECTS. FORECAST MAX TEMPERATURE GRIDS LEAN TOWARD THE WARMER GUIDANCE SOURCES...SO HOPEFULLY THIS IS NOT JUST A WISHCAST. SUNDAY NIGHT AND MONDAY A COLD FRONT ASSOCIATED WITH LOW PRESSURE MOVING ACROSS ONTARIO AND QUEBEC THEN PASSES THROUGH THE AREA EARLY MONDAY. TEMPERATURES ONLY GRADUALLY FALL SUNDAY NIGHT AHEAD OF THE FRONT...AND THEN REMAIN NEARLY FLAT IN POST FRONTAL FLOW DURING THE DAY MONDAY. HIGHS ON MONDAY MAY OCCUR AT MIDNIGHT SUNDAY NIGHT ESPECIALLY IN THE NORTH. FOR MOST OF THE REGION THIS LOOKS TO BE A DRY FRONTAL PASSAGE...AS THE BEST LIFT AND SATURATION IS FOCUSED NORTH OF THE AREA CLOSER TO THE LOW. MONDAY NIGHT AND TUESDAY DETERMINISTIC MODELS SHOW REASONABLE AGREEMENT ON THE POSITION OF A LONGWAVE UPPER TROUGH PASSING THROUGH THE GREAT LAKES LATE MONDAY INTO TUESDAY...BUT CONSIDERABLE DISAGREEMENT ON THE TIMING AND LOCATION OF A SURFACE LOW ASSOCIATED WITH A SHORTWAVE TRAVERSING THE SOUTHERN EXTENT OF THE UPPER TROUGH. THE GFS IS THE MOST PROGRESSIVE WITH THIS FEATURE...THE ECM/GEM ARE THE SLOWEST...AND THE NAM SOMEWHAT SPLITS THE DIFFERENCE. THE ACTUAL TRACK THAT DEVELOPS WILL DETERMINE BOTH TEMPERATURES AND SNOWFALL POSSIBILITIES TUESDAY...BUT UNFORTUNATELY IT STILL IS A BIT EARLY TO LEAN TOO HEAVILY ON ANY SOLUTION. REGARDLESS OF THE FINAL TRACK...THIS PERIOD APPEARS TO BRING THE BEST CHANCE LOCALLY FOR A QUICK SHOT OF ACCUMULATING SNOWFALL OVER THE NEXT WEEK. TUESDAY NIGHT AND WEDNESDAY THE SURFACE LOW AND ANY ASSOCIATED SNOW THAT MODELS CANNOT AGREE ON TUESDAY WILL EXIT THE AREA BY EARLY WEDNESDAY...USHERING IN ANOTHER PERIOD OF COLD NORTHWEST FLOW THAT DROPS OVERNIGHT LOWS INTO THE SINGLE DIGITS FOR SOME AREAS AND KEEPS A LID ON THE DAYTIME WARMING WEDNESDAY...LIMITING HIGHS TO THE TEENS TO AROUND 20. WEDNESDAY NIGHT AND THURSDAY WINDS QUICKLY TURN SOUTHWEST AGAIN WEDNESDAY NIGHT AND THURSDAY PRODUCING ANOTHER POTENTIAL MILD WARMUP TO ABOVE FREEZING TEMPERATURES THURSDAY. IN REALITY THIS MAY END UP BEING LESS OF A WARMUP IF THE FASTER MODEL SOLUTIONS ARE TO BE BELIEVED AND THE NEXT IN AN ENDLESS SERIES OF COLD FRONTS MOVES THROUGH THE AREA EARLIER IN THE DAY THURSDAY. THURSDAY NIGHT INTO SATURDAY REGARDLESS OF THE FRONTAL TIMING ON THURSDAY...TEMPERATURES FALL THURSDAY NIGHT AND CONTINUE TO FALL THROUGH THE FRIDAY MORNING PERIOD...THEN REMAIN FLAT OR ONLY GRADUALLY RISING DURING THE DAY FRIDAY. COLD NORTHWEST WINDS REMAIN OVER THE AREA INTO SATURDAY AND KEEP TEMPERATURES BELOW SEASONABLE NORMS. LENNING && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 22Z... * MVFR CIGS CONTINUING INTO THE EARLY OVERNIGHT HOURS...MAY LOWER TOWARDS 010-015 THIS EVENING. * WEST WINDS WITH OCCASIONAL GUSTS AROUND 20 KT LATE THIS AFTERNOON BEFORE DIMINISHING THIS EVENING. SOUTH-SOUTHWEST WINDS INCREASE SUNDAY MORNING GUSTING 25-30 KT. MDB //DISCUSSION...UPDATED 22Z... ONE BAND OF CLOUD COVER HAS BEEN TRYING TO DEPART TO THE EAST TODAY BUT ANOTHER CONTINUES TO WORK SOUTHEAST INTO THE AREA. DO NOT EXPECT ANY CLEARING/SCATTERING AT THE TERMINALS THIS AFTERNOON AS THIS NEXT BAND CONTINUES TO MOVE IN. EXPECT MVFR TO CONTINUE AS A RESULT THOUGH THERE MAY BE SOME LOWERING FROM CURRENT BASES NEAR 2000 FT DOWN INTO THE 1000-1500 FT RANGE THIS EVENING BEFORE SCATTERING OCCURS LATER TONIGHT. MDB FROM 18Z... LOW PRESSURE SYSTEM NORTHEAST OF LAKE HURON BROUGHT A TRAILING FRONTAL BOUNDARY ACROSS NORTHERN IL/NORTHWEST IN AIRFIELDS EARLY THIS MORNING. BEHIND THIS BOUNDARY WINDS BECAME MORE WESTERLY...AND HAVE GUSTED AT TIMES TO 20-22KT. SKIES HAVE REMAINED POOR WITH CIGS ARND 1200-1500FT AGL. GUIDANCE HAS BACKED OFF ON CIGS IMPROVING MUCH BEYOND CURRENT HEIGHTS...HOWEVER BASED ON LATEST SATELLITE IMAGERY SOME THINNING IS TAKING PLACE ACROSS EASTERN IOWA/FAR WESTERN IL. ALTHOUGH THIS CLEARING DOES NOT LOOK LIKE IT WILL MAKE IT ALL OF THE WAY TO ORD/MDW. BASED ON THE LOWER CONFIDENCE IN CIGS LIFTING TO VFR OR ERODING ALL TOGETHER...HAVE HELD ONTO LOW END MVFR BKN DECK. FURTHER WEST AT RFD AND POSSIBLY DPA...SKIES MAY BRIEFLY BECOME SCT AFT 02Z THIS EVENING AND LINGER THRU MIDNIGHT BEFORE BECOMING BKN YET AGAIN. WITHIN THIS WINDOW OF SCT CIGS...SHALLOW GROUND FOG MAY DEVELOP AT RFD/DPA. WINDS WILL REMAIN LIGHT FROM THE WEST ARND 8-10KT...THEN ARND DAYBREAK SUN WINDS BEGIN TO TURN MORE SOUTHWESTERLY AND EVENTUALLY SOUTHERLY BY MIDDAY SUN. WITH A TIGHTENING GRADIENT EXPECTED SUN...AND THIN CLOUD COVER WITH THE EXCEPTION OF A CIRRUS DECK...WINDS WILL BECOME BREEZY AT 18 TO 22KT WITH GUSTS UP TO 30 KT IN THE AFTN HOURS. BEACHLER //ORD AND MDW CONFIDENCE...UPDATED 22Z... * HIGH CONFIDENCE IN MVFR CIGS INTO THE OVERNIGHT HOURS...WITH MEDIUM CONFIDENCE IN SOME LOWERING THIS EVENING. MEDIUM CONFIDENCE IN TIMING OF SCATTERING/CLEARING. * HIGH CONFIDENCE IN WIND DIR/SPEED/GUSTS. MDB //OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z... SUNDAY NIGHT...LLWS POSSIBLE EARLY...CHANCE OF IFR CIGS. MONDAY...SMALL CHANCE OF MVFR OR POSSIBLY IFR CIGS. TUESDAY...SNOW AND IFR ARE POSSIBLE. WEDNESDAY...VFR PROBABLE. THURSDAY...MVFR CIGS POSSIBLE. FRIDAY...VFR PROBABLE. IZZI && .MARINE... 223 PM CST LOW PRESSURE WILL CONTINUE TO LIFT ACROSS ONTARIO AND QUEBEC THROUGH THE OVERNIGHT HOURS WHILE A RIDGE WILL BUILD INTO THE WESTERN LAKES REGION. W/NW WINDS WILL PEAK AROUND 30 KT THIS EVENING...THEN SHOULD BACK TO THE SOUTH DIMINISH SOME OVERNIGHT. SOUTHWEST WINDS BEGIN TO QUICKLY PICK UP AGAIN DURING THE DAY SUNDAY AS ANOTHER LOW TRACKS EAST ACROSS THE CANADIAN PRAIRIES. GALES TO 40 KT ARE POSSIBLE SUNDAY AND SUNDAY NIGHT AND A GALE WATCH REMAINS IN EFFECT FOR THIS PERIOD. DECIDED NOT TO UPGRADE TO A WARNING YET BECAUSE OF MODERATE DIFFERENCES BETWEEN THE MODELS MAINLY CONCERNING THE AMOUNT OF STABILITY THAT WILL DEVELOP IN THE WARM ADVECTION OVER THE WATERS WHICH COULD INHIBIT WINDS. A COLD FRONT WILL SWEEP ACROSS LAKE MICHIGAN MONDAY WITH WINDS TURNING WESTERLY TO AROUND 30 KT. A CLIPPER SYSTEM IS FORECAST TO IMPACT THE REGION TUESDAY THOUGH THERE REMAINS CONSIDERABLE SPREAD IN THE MODELS REGARDING THE TRACK AND TIMING OF THE LOW. CONTINUE TO LEAN TOWARDS DEEPER/SLOWER SOLUTIONS SUCH AS THE GEM/ECWMF. YET ANOTHER SIGNIFICANT LOW IS EXPECTED TO DROP INTO THE NORTHERN LAKES REGION THURSDAY INTO FRIDAY. THIS DEEP LOW WILL LIKELY BRING STRONG GALES TO LAKE MICHIGAN...AND CANNOT RULE OUT STORM FORCE WINDS AT THIS TIME. BMD && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS UNTIL 10 PM SATURDAY. GALE WATCH...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565- LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868- LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...11 AM SUNDAY TO 3 AM 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
  [top] Area Forecast Discussion National Weather Service Lincoln IL 315 PM CST Sat Jan 11 2014 .DISCUSSION... ISSUED 316 PM CST Sat Jan 11 2014 A progressive upper level pattern is expected for much of the upcoming week in the Midwest. The result will fairly quiet weather with only minor chances of light precipitation and fluctuating temperatures. SHORT TERM...Tonight through Monday Cooler temperatures are expected tonight with a light west wind. However, readings will still be above typical values for mid- January. Low level warm advection will kick in Sunday as low and mid level wind field back to more of southwesterly flow. In addition, the latest visible satellite and observations from early today indicate that there are only a few areas of widespread snow cover remaining west of the Illinois River and along the I-70 corridor. This will allow temperatures to climb well into the 45 to 50 degree range Sunday afternoon, which in turn will melt most of the remaining snow. Should see a return to mostly cloudy conditions this evening, especially in northern and central IL. However, as the main upper level trough over us now rapidly shifts to the east overnight, subsidence should result in decreasing clouds late tonight. Only a few clouds are expected Sunday, which will help warm things up. An upper level trough, now approaching the western U.S. coast will quickly move toward the Midwest by Monday. At the same time, an upper low in the Baja region will lift out with the advancing trough. This southern stream system may bring some light rain into parts of southeast IL, but overall the forecast area will remain dry on Monday but turn colder as a cold front moves through during the morning. LONG TERM...Tuesday through Saturday The best chance for precipitation in the longer term looks to be Tuesday as a fast moving Clipper system moves across northern Illinois early in the day. Moisture will be rather sparse, so light precipitation is expected during the day Tuesday. Low level temperature fields could be warm enough for rain or a rain/snow mix south of a Jacksonville-SPI-MTO-Marshall line Tuesday morning. However, increasing northwest winds and cold advection during the day Tuesday would be more conducive for light snow in nearly all of the forecast area by afternoon, along with falling temperatures. The exception may be areas south of I-70, so will keep the potential for a mix of rain/snow there all day. High pressure will settle in for Wednesday with clearing skies and a return to chilly temperatures. The longer range models are in generally good agreement by showing a building ridge in western U.S. with a developing northwest flow over the Midwest by Friday. This would result in a brief warm up for Thursday, followed by a return to colder than normal temperatures for the end of the week. There is some disagreement as to how far south any associated precpitation may develop for late in the week. The GFS indicates a clear cut lake effect snow situation, while the European model is a bit stronger and colder with its upper level pattern - resulting in light snow reaching central IL. Will keep the forecast dry for now and wait for more consistent model runs to see if there is enough low level moisture and forcing to mention late week light snow. Miller && .AVIATION... ISSUED 1150 AM CST Sat Jan 11 2014 1725z satellite imagery shows back edge of the cloud cover along a KPIA to KSPI line. Based on timing tools, clearing will reach KDEC and KBMI by 19z and KCMI by 20z. Once these clouds leave the TAF sites, the next issue will be monitoring low clouds currently sinking southeastward into central Iowa. Trajectory of this cloud cover brings it across the northern half of the KILX CWA late this afternoon and evening. HRRR has a very good handle on the clouds initially, but then tends to re-develop low clouds on the back side of the deck across Iowa tonight, resulting in a slow clearing trend overnight. NAM forecast soundings seem a bit more reasonable based on current satellite trends, so will lean toward this solution. As such, have brought MVFR ceilings back into KPIA after 22z, then further east to KBMI and KCMI after 00z. Clouds will then depart during the 06z to 08z time frame. Further south, think cloud area will only graze the southernmost terminals, so will keep skies mostly clear this evening at both KSPI and KDEC. Winds will initially be from the west with gusts to between 20 and 25kt this afternoon, then will diminish to less than 10kt overnight. As high pressure shifts east of the area, winds will back to southerly and gust to between 15 and 20kt by Sunday morning. Barnes && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1211 PM CST SAT JAN 11 2014 .DISCUSSION... 334 AM CST SHORT TERM...TODAY THROUGH MONDAY IN THE NEAR TERM...PRIMARY CONCERN IS WITH EXTENT AND DURATION OF DENSE FOG AHEAD OF COLD FRONT TRAILING FROM LOW PRESSURE NEAR THE U.P. OF MICHIGAN. WILL MAKE A DECISION BEFORE SENDING OUT ZONES ON WHETHER TO ISSUE A DENSE FOG ADVISORY THRU THE EARLY MORNING...LIKELY FOR AREAS ALONG/EAST OF I-57...OR RIDE WITH AN SPS. COLD FROPA AND SHIFT TO WEST WINDS WILL RESULT IN QUICK IMPROVEMENT IN VSBY AS IS OCCURRING CURRENTLY IN NW IL. ANY LINGERING RAIN SHOWERS OVER EASTERN CWA WILL BE OFF TO THE EAST BY MID MORNING...IF NOT SOONER. REST OF TODAY-TONIGHT... A LOOK AT OBSERVATIONS AND FOG PRODUCT SATELLITE SHOWS EXTENSIVE OVC WELL BEHIND COLD FRONT BACK TO CENTRAL IA. HAVE SLOWED CLEARING TREND IN SKY GRIDS...SO MOST OF THE DAYLIGHT HOURS WILL LIKELY BE SPENT CLOUDY TODAY FOR MUCH OF THE AREA. CONTINUED MODEST COOL ADVECTION IN WAKE OF FRONT IS EXPECTED TO YIELD MORNING HIGHS...THOUGH THERE COULD BE SOME IMPROVEMENT IN THE AFTERNOON DESPITE CLOUD COVER. SKIES WILL CLEAR THIS EVENING AND TONIGHT...AND THOUGH THERE WILL BE WARM ADVECTION DEVELOPING...SOUTHWESTERLY FLOW COULD WEAKEN ENOUGH TO ALLOW FOR INVERSION AND DECOUPLING. HAVE TRENDED LOWS A BIT COLDER/MID TEENS/FOR AREAS THAT RETAIN A DEEP SNOW PACK WEST OF FOX VALLEY/RFD STILL AT 9 INCHES AS OF 06Z. SUNDAY-SUNDAY NIGHT... A STRONG LOW PRESSURE AREA WILL BE TRACKING ACROSS THE CANADIAN PRAIRIES TO WESTERN ONTARIO...THOUGH WEAKENING SOME WITH TIME. STRONG WARM ADVECTION ALOFT AND GUSTY SSW SURFACE FLOW WILL ENABLE A QUICK WARM UP. 925 MB TEMPS WARMING TO +4 TO +6C ACROSS THE AREA EXPECTED TO SUPPORT HIGHS IN THE LOW TO MID 40S EAST OF A LINE FROM UGN TO VYS...WITH U30S TO AROUND 40 TO THE WEST OF THAT LINE WHERE SNOW PACK WILL BE SLOWER TO MELT. IN ADDITION...GOOD PRESSURE FALLS ESPECIALLY DURING THE AFTERNOON WILL RESULT IN WINDY CONDITIONS...WITH GUSTS SOLIDLY IN THE 30-35 MPH RANGE AND POSSIBLY HIGHER IF THE STRONGER MOMENTUM FURTHER ALOFT CAN BE TAPPED INTO. A COLD FRONT TRAILING FROM THE LOW WILL SWING THROUGH THE AREA SUNDAY NIGHT...AND EXPECTING IT TO BE A DRY FROPA...AS GUIDANCE SHOWING ANY QPF SUCH AS THE NAM APPEARS TO BE STRUGGLING WITH LOW LEVEL MOISTURE PROFILES. MONDAY... GUIDANCE HAS TRENDED FARTHER SOUTHEAST AND QUICKER WITH SOUTHERN STREAM SYSTEM...SO SLIGHT POPS CURRENTLY IN GRIDS IN FAR SOUTHEAST ON MONDAY MORNING MAY BE ABLE TO BE REMOVED IF TRENDS CONTINUE. IF ANY PRECIP OCCURS AT THAT TIME...IT WOULD BE IN THE FORM OF RAIN. THERE WILL BE COLD ADVECTION BEHIND THE FRONT...THOUGH MODELS DIFFER ON STRENGTH AND TIMING DURING MONDAY. CURRENTLY ONLY HAVE A MINOR RISE IN TEMPS ON MONDAY FROM SUNDAY NIGHT LOWS...BUT IF FASTER GFS VERIFIES...TEMPS WILL BE MORE LIKELY TO FALL THROUGH THE DAY ON MONDAY. LONG TERM...MONDAY NIGHT THROUGH FRIDAY... THINGS DO GET A BIT MORE INTERESTING MONDAY NIGHT. OPERATIONAL MODELS HAVE COME INTO BETTER AGREEMENT ON A STRONG CLIPPER SYSTEM TRACKING TOWARD THE AREA OVERNIGHT INTO TUESDAY...THOUGH GFS WHICH HAS HAD THIS SYSTEM FOR A FEW RUNS NOW...IS MUCH FASTER WITH IT. THE INDIVIDUAL GFS ENSEMBLES ARE ALL FEATURING THIS SYSTEM AS WELL...THOUGH WITH DECENT SPREAD IN TRACK AND TIMING. DESPITE UPPER WAVE AND SURFACE LOW BEING FAIRLY STOUT AS CURRENTLY MODELED...THESE NORTHWEST FLOW SYSTEMS FROM THIS RANGE TYPICALLY SHOW LARGE RUN TO RUN VARIANCE UNTIL GUIDANCE BETTER SAMPLES ASSOCIATED FEATURES. FOR NOW HAVE FAVORED THE SLOWER ECMWF (WHICH FINALLY CAME INTO LINE WITH OTHER MODELS WITH THIS SYSTEM) AND GGEM...WHICH RESULTS IN CHANCE POPS INTO THE FAR NORTH AFTER MIDNIGHT. HAVE RAISED POPS TO CHANCE RANGE ACROSS THE AREA DURING THE DAY ON TUESDAY. THERMAL PROFILES INDICATE P-TYPE WOULD BE IN FORM OF SNOW...BUT TRACK OF LOW AND 850 MB LOW...WILL BE KEY AS TO WHETHER WE SEE A GLANCING BLOW OR EVEN DECENT ACCUMULATING SNOW FROM THIS SYSTEM. AFTER THIS POSSIBLE SYSTEM...WEDNESDAY LOOKS TO BE A COLD DAY WITH THERMAL TROUGH OVERHEAD. HOWEVER MEDIUM RANGE GUIDANCE THEN FAVORS A VERY DEEP SYSTEM TRACKING ALONG THE CANADIAN BORDER ON THURSDAY...WITH A QUICK WARM UP TO OR ABOVE FREEZING LIKELY IN THAT SET-UP. THE EASTERN TROUGH WILL DEEPEN IN THE WAKE OF THIS SYSTEM...WITH POTENTIAL FOR A COLD AIR MASS/THOUGH NOT THAT TERRIBLY COLD IN CONTEXT OF THIS WINTER SO FAR/TO CLOSE THE WORK WEEK WITH 850 MB TEMPS IN THE MINUS TEENS CELSIUS IF NOT A BIT COLDER. HIGHS MAY REMAIN IN THE TEENS FOR AT LEAST PARTS OF THE AREA ON FRIDAY. RC && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 18Z... * LOW END MVFR CIGS LINGERING THRU THIS AFTN...POSSIBLY A PERIOD OF CIGS THINNING TO A SCT DECK...THEN BACK TO BKN LATE TONIGHT. * WEST WINDS TO 16KT WITH GUSTS ARND 20-22KT THRU THIS AFTN. GUSTS DIMINISH THIS EVE...THEN RETURN AGAIN LATE SUN MORNING AND COULD BE GUSTING TO 28KT SUN MIDDAY/AFTN. BEACHLER //DISCUSSION...UPDATED 18Z... LOW PRESSURE SYSTEM NORTHEAST OF LAKE HURON BROUGHT A TRAILING FRONTAL BOUNDARY ACROSS NORTHERN IL/NORTHWEST IN AIRFIELDS EARLY THIS MORNING. BEHING THIS BOUNDARY WINDS BECAME MORE WESTERLY...AND HAVE GUSTED AT TIMES TO 20-22KT. SKIES HAVE REMAINED POOR WITH CIGS ARND 1200-1500FT AGL. GUIDANCE HAS BACKED OFF ON CIGS IMPROVING MUCH BEYOND CURRENT HEIGHTS...HOWEVER BASED ON LATEST SATELLITE IMAGERY SOME THINNING IS TAKING PLACE ACROSS EASTERN IOWA/FAR WESTERN IL. ALTHOUGH THIS CLEARING DOES NOT LOOK LIKE IT WILL MAKE IT ALL OF THE WAY TO ORD/MDW. BASED ON THE LOWER CONFIDENCE IN CIGS LIFTING TO VFR OR ERODING ALL TOGETHER...HAVE HELD ONTO LOW END MVFR BKN DECK. FURTHER WEST AT RFD AND POSSIBLY DPA...SKIES MAY BRIEFLY BECOME SCT AFT 02Z THIS EVENING AND LINGER THRU MIDNIGHT BEFORE BECOMING BKN YET AGAIN. WITHIN THIS WINDOW OF SCT CIGS...SHALLOW GROUND FOG MAY DEVELOP AT RFD/DPA. WINDS WILL REMAIN LIGHT FROM THE WEST ARND 8-10KT...THEN ARND DAYBREAK SUN WINDS BEGIN TO TURN MORE SOUTHWESTERLY AND EVENTUALLY SOUTHERLY BY MIDDAY SUN. WITH A TIGHTENING GRADIENT EXPECTED SUN...AND THIN CLOUD COVER WITH THE EXCEPTION OF A CIRRUS DECK...WINDS WILL BECOME BREEZY AT 18 TO 22KT WITH GUSTS UP TO 30 KT IN THE AFTN HOURS. BEACHLER //ORD AND MDW CONFIDENCE...UPDATED 18Z... * HIGH CONFIDENCE IN WIND DIR/SPEED/GUSTS. * MEDIUM CONFIDENCE IN CIGS FORECAST. * LOW CONFIDENCE IN CIGS CLEARING. * HIGH CONFIDENCE IN SHALLOW FOG REMAINING WEST OF ORD/MDW TONIGHT. BEACHLER //OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z... SUNDAY NIGHT...LLWS POSSIBLE EARLY...CHANCE OF IFR CIGS. MONDAY...SMALL CHANCE OF MVFR OR POSSIBLY IFR CIGS. TUESDAY...SNOW AND IFR ARE POSSIBLE. WEDNESDAY...VFR PROBABLE. THURSDAY...MVFR CIGS POSSIBLE. FRIDAY...VFR PROBABLE. IZZI && .MARINE... 155 AM CST APPEARS AS THOUGH WE WILL ENTER ANOTHER BUSY PERIOD ON LAKE MICHIGAN WITH SEVERAL BOUTS OF GALES EXPECTED OVER THE NEXT WEEK AND ONLY BRIEF TIME WINDOWS OF LIGHTER WINDS. A MODERATELY STRONG WEST WIND WILL DEVELOP TODAY IN THE WAKE OF LOW PRESSURE DEPARTING THE REGION WITH A BRIEF LULL IN THE WINDS LATE TONIGHT INTO EARLY SUNDAY MORNING AS THEY BACK TO SOUTHWEST. AN INTENSE AND FAST MOVING LOW WILL RACE EAST ACROSS CANADA SUNDAY RESULTING IN A PERIOD OF SOUTH GALES...PROBABLY HIGHER END GALES OVER NORTHERN PORTIONS OF THE LAKE SUNDAY AFTERNOON AND EVENING. WHILE WINDS SHOULD EASE BELOW GALE FORCE BY MONDAY MORNING THEY SHOULD REMAIN FAIRLY STRONG THROUGH THE DAY MONDAY. TRACK/TIMING DIFFERENCES EXIST REGARDING A FAIRLY STRONG CLIPPER RACING SOUTHEAST INTO THE MIDWEST TUESDAY WITH ANOTHER PERIOD OF STRONG NORTHERLY WINDS AND POSSIBLE GALES IN THE WAKE OF THAT SYSTEM LATE TUESDAY OR EARLY WEDNESDAY. YET ANOTHER PERIOD OF GALES LOOKS LIKE A GOOD BET BY THURSDAY. IZZI && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS UNTIL 10 PM SATURDAY. GALE WATCH...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565- LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868- LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...11 AM SUNDAY TO 3 AM 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 National Weather Service Lincoln IL 1150 AM CST Sat Jan 11 2014 .DISCUSSION... ISSUED 1045 AM CST Sat Jan 11 2014 Primary forecast challenge today will be sky trends. 16z/10am satellite imagery shows widespread cloud cover across most of the KILX CWA: however, clearing is beginning to work its way into west-central Illinois. Based on timing tools, skies will partially clear as far east as the I-55 corridor by early afternoon, then further east to the Indiana border after 4 PM. The potential complication with the clearing trend is another deck of low clouds currently dropping southeastward into central Iowa. Timing tools bring this cloud area into the Illinois River Valley by early afternoon, then spread it eastward across the northern half of the CWA through the evening hours. NAM forecast soundings have a good handle on the clouds, although clouds appear to be moving a bit faster than the model projects. End result will be a cloudy morning giving way to partly to mostly sunny skies by early afternoon, followed by increasing clouds from the northwest once again by mid to late afternoon. Will send updated zones shortly. Barnes && .AVIATION... ISSUED 1150 AM CST Sat Jan 11 2014 1725z satellite imagery shows back edge of the cloud cover along a KPIA to KSPI line. Based on timing tools, clearing will reach KDEC and KBMI by 19z and KCMI by 20z. Once these clouds leave the TAF sites, the next issue will be monitoring low clouds currently sinking southeastward into central Iowa. Trajectory of this cloud cover brings it across the northern half of the KILX CWA late this afternoon and evening. HRRR has a very good handle on the clouds initially, but then tends to re-develop low clouds on the back side of the deck across Iowa tonight, resulting in a slow clearing trend overnight. NAM forecast soundings seem a bit more reasonable based on current satellite trends, so will lean toward this solution. As such, have brought MVFR ceilings back into KPIA after 22z, then further east to KBMI and KCMI after 00z. Clouds will then depart during the 06z to 08z time frame. Further south, think cloud area will only graze the southernmost terminals, so will keep skies mostly clear this evening at both KSPI and KDEC. Winds will initially be from the west with gusts to between 20 and 25kt this afternoon, then will diminish to less than 10kt overnight. As high pressure shifts east of the area, winds will back to southerly and gust to between 15 and 20kt by Sunday morning. Barnes && .PREV DISCUSSION... ISSUED 240 AM CST Sat Jan 11 2014 Area of dense fog has been rolling eastward across the state early this morning ahead of a cold front, which was just crossing the Illinois/Iowa border at 2 am. The back edge of the fog is about 50-75 miles east of the front, so am most concerned east of the Illinois River for the next few hours. The lingering rain was mainly along the Indiana border and should be out of the forecast area soon. Temperatures have remained quite mild overnight, with upper 30s and lower 40s in many areas except the far northwest. Main forecast concerns involve precipitation chances next week, with periodic clipper systems zipping southeast. Also have some concerns with the extent of cold air late next week, with discrepancies between the GFS and ECMWF models on how far south the cold air will surge. SHORT TERM...Today through Monday: Will drop the dense fog advisory west of the Illinois River. HRRR has been doing a reasonable job with the low visibilities, and the threat will be more across the east. Will expand the advisory to cover the remainder of the CWA east of I-57 for a few hours early this morning, and extend the time a bit to around 7 am. Much of the fog should be out of the area by that point, except perhaps around Champaign and Danville. Deep upper trough to quickly swing eastward today, followed by another broadening trough early next week. Southerly winds to 25-30 mph and decent sunshine should boost temperatures into the mid-upper 40s everywhere, with some lower 50s in the southwest and southeast corners of the CWA. Cooler conditions on Monday as a cold front passes with the trough. Surge of moisture pushing northeast from the lower Mississippi Valley ahead of the trough has trended a bit further east with the latest model runs, and associated rainfall may largely miss us. Have maintained some 30-40% PoP`s mainly in the morning across the eastern CWA, but would not be surprised to see those continue to lower with subsequent forecasts. LONG TERM...Tuesday through Friday: Active upper pattern on tap for the upcoming week, with concerns for light precipitation and surge of cold air. Regarding the precipitation, first clipper will be racing southeast Monday night. The GFS is much more progressive and keeps the precip to the north, while the ECMWF and GEM models favor a more southern track and somewhat higher chances of precip. Have raised PoP`s a bit from the initialization levels to favor these latter models, and will mention a chance of snow on Tuesday, with a mix in the afternoon in the central and south. Second and stronger system will track more across the northern Great Lakes region and have kept precip chances out of our area, but Thursday and Thursday night will be rather windy. Latest ECMWF continues its trend of plunging a lobe of cold air much further south than the GFS late in the week, as the former model digs the eastern U.S. trough much deeper. 850 mb temps of -18C on the ECMWF would favor some teens for highs by Friday, while the GFS`s trough is already well to our east. Have not gone as cold as the ECMWF, but will continue with highs below freezing in all areas on Friday. Geelhart && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
341 PM EST SAT JAN 11 2014 .SYNOPSIS... A COLD FRONT CROSSES THE AREA LATE TODAY. HIGH PRESSURE RETURNS FROM THE WEST TONIGHT INTO SUNDAY. ANOTHER COLD FRONT APPROACHES FROM THE WEST LATE MONDAY. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... RADAR MOSAIC INDICATING LEADING EDGE OF SQUALL LINE MOVING A BIT QUICKER THAN PROGGED EVEN BY FASTEST HRRR SOLUTION. HAVE ACCORDINGLY MOVED SHRAS OUT A BIT FASTER WITH LATEST FORECAST PACKAGE. LATEST WEATHER ANALYSIS SHOWS ERODING WEDGE FRONT NOW JUST WEST OF RIC METRO...EXTENDING SOUTH INTO THE WESTERN CAROLINAS. VIA SPC MESOANALYSIS, LEADING EDGE OF CONVECTION NOW CROSSING INTO WESTERN EDGE OF TOR WATCH BOX...IN EFFECT FOR SE VA /HAMPTON ROADS AND TIDEWATER/ AND NE NC UNTIL 01Z. LATEST WX ANALYSIS SHOWS APPROACHING COLD FRONT CURRENTLY PUSHING INTO WESTERN VA AT 20Z. AS EXPECTED, SEEING A NARROW LINE OF FORCED LOW TOPPED CONVECTION OVER EASTERN VA ATTM. PER SPC MESOANALYSIS, MLCAPE ON THE ORDER OF 500-1000 J/KG OVER THE WARM SECTOR (ALONG WITH 50-70 KT OF 0-6KM SHEAR AND LOW/MIDLVL LAPSE RATES OF 6-7 C/KM) HAS PROVED SUFFICIENT TO MIX DOWN STRONG 60-80KT WINDS JUST ABOVE THE DECK (AKQ VWP SHOWING SW WINDS ~60KT BETWEEN 1-2KFT UP). AS CONVECTIVE LINE ROLLS EAST, EXPECT DAMAGING WIND THREAT TO CONTINUE ACROSS THE SE THROUGH EARLY EVENING. ONCE THE COLD FRONT CLEARS THE AREA THIS EVENING...DRIER AIR RETURNS TONIGHT WITH CLEARING SKIES. LOWS TONIGHT IN THE MID 30S TO MID 40S. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY/... SUNDAY LOOKS LIKE A TRANSITION DAY AS AN UPPER TROUGH PIVOTS OFFSHORE AND QUASI-ZONAL FLOW BRINGS A MOSTLY SUNNY SKY. WHILE NOT NEARLY AS MILD AS SATURDAY...MAXIMA REMAIN ~1 S.D. ABOVE NORMAL...CLIMBING INTO THE MID 50S TO NEAR 60. FLOW ALOFT BECOMES INCREASINGLY SW ON MONDAY...WITH GRADUALLY INCREASING HIGH CLOUDS LATER IN THE DAY AS AN UPPER LEVEL TROUGH BARRELS EASTWARD FROM THE PLAINS MONDAY INTO MONDAY NIGHT. WARM SW FLOW ALLOWS MAXIMA TO WARM BACK INTO THE UPR 50S TO LOW 60S. && .LONG TERM /MONDAY NIGHT THROUGH SATURDAY/... MEDIUM RANGE MODELS CONTINUE TO SHOW GENERAL AGREEMENT WITH AMPLIFIED...BUT PROGRESSIVE UPPER LEVEL PATTERN THRU THE EXTENDED PERIOD. LONGWAVE TROUGH WILL SLOWLY PROGRESS EWD OVER THE MIDWEST MON NIGHT-TUES MORNING AS ADDITIONAL SHORTWAVE ENERGY DIGS OVER THE NRN PLAINS INTO THE MIDWEST. LEADING ENERGY WILL LIFT FROM THE GULF STATES NEWD INTO THE MID-ATLANTIC REGION TUES. ECMWF REMAINS MORE AMPLIFIED WITH THE LEADING ENERGY THAN OTHER MODELS...RESULTING IN STRONGER SWLY FLOW AND RESULTANT MOISTURE ADVECTION INTO THE REGION. DIFFERENCES IN STRENGTH ALSO AFFECT PLACEMENT OF SFC LOW PRESSURE AND ATTENDANT WAVY FRONT OVER THE REGION. STRONGER ECMWF SOLUTION DEVELOP A WAVE ALONG THE FRONT OVER THE MID-ATLANTIC REGION WHILE THE WEAKER GFS QUICKLY PUSHES THE WEAK/WAVY FRONT OFFSHORE. TRENDED FORECAST TOWARD ECMWF BASED ON RUN TO RUN CONSISTENCY AND PV FIELDS (BETTER PLACEMENT OF SFC FEATURES WRT TO UPPER LEVEL FIELDS). WILL MAINTAIN CHANCE-HIGH END CHANCE POPS TUES MORNING-AFTERNOON...WITH PRECIP PUSHING OFFSHORE BY EARLY TUES NIGHT. MOISTURE REMAINS RATHER SHALLOW...AND WITH PROGRESSIVE NATURE OF THE SYSTEM...QPF AMOUNTS WILL GENERALLY BE LESS THAN ONE QUARTER OF AN INCH. MEANWHILE...ENERGY WILL CONTINUE TO DIG OVER THE MIDWEST INTO THE GULF STATES TUES INTO TUES NIGHT. ADDITIONAL SFC PATTERN PROBLEMS ARISE...MAINLY WITH THE PLACEMENT OF THE SFC LOW. HOWEVER...MODELS BOTH INDICATING A COLD FRONT WILL CROSS THE AREA WEDS. LEADING VORTICITY MAXIMA WILL LIFT FROM THE GULF STATES INTO THE MID-ATLANTIC WEDS...WITH A WAVE POSSIBLY DEVELOPING ALONG THE FRONT OVER THE REGION. THIS COULD LEAD TO THE DEVELOPMENT OF A COASTAL LOW OFF THE MID-ATLANTIC COAST WEDS AFTERNOON. STRONG DYNAMICS LOOK TO OVERCOME LIMITED MOISTURE FOR PRECIP WEDS. HOWEVER...LOW CONFIDENCE DUE TO MODEL SPREAD WILL RESULT IN ONLY SLIGHT CHANCE-LOW END CHANCE POPS ATTM. RAIN/SNOW MIX WILL BE POSSIBLE EARLY WED ACROSS THE FAR NW ZONES. TROUGH AXIS WILL PUSH OFFSHORE WED NIGHT-THURS MORNING AS SFC HIGH PRESSURE BUILDS EWD OVER THE DEEP SOUTH...RIDGING NWD INTO THE LOCAL AREA. NRN STREAM WILL REMAIN ACTIVE AS ANOTHER SHORTWAVE DIGS OVER THE GREAT LAKES REGION LATE THURS-FRI...PUSHING A COLD FRONT ACROSS THE OH VALLEY INTO THE MID-ATLANTIC REGION FRI. COLD CANADIAN HIGH PRESSURE WILL BUILD OVER THE MIDWEST-GULF STATES FRI-SAT AS COLD AIR RETURNS TO THE REGION. PACIFIC ORIGIN OF THE COLD AIR WILL PREVENT THE EXTREME TEMPS SEEN IN THE PREVIOUS WEEK. HIGH TEMPS WILL WARM ABOVE NORMAL TUES (UPPER 50S-LOW 60S) BEFORE FALLING BACK TO SEASONABLE NORMS THRU THE END OF THE WEEK. HIGHS SAT EXPECTED IN THE UPPER 30S-LOW 40S. MILD MON NIGHT (LOW-MID 40S) BEFORE RETURNING TO NEAR OR SLIGHTLY ABOVE SEASONABLE LOWS (LOW-MID 30S) THRU THE EXTENDED. && .AVIATION /21Z SATURDAY THROUGH THURSDAY/... MAIN CONCERN FOR THE AFTN/EVNG IS THE CONVECTION AHEAD OF THE APPROACHING CDFNT. S WNDS HAVE INCREASED (20-25 KT) AND WILL BECOME GUSTY (30 KT) INTO THIS AFTN AS THE LINE MAKES ITS WAY EAST. TIMING OF SIGNIFICANT AREA OF PCPN ON RADAR HAS THE PRECIP THROUGH THE REGION FROM MID AFTN THROUGH 00-03Z/12. THERE IS A CHANCE FOR SCATTERED THUNDERSTORMS AHEAD OF THE LINE DUE TO STRONG LOW LEVEL WINDS AND THE WARM/MOIST AIRMASS OVER NE NC AND SE VA. THUNDER AND STRONGER WINDS(40-50 KT) ALONG THE LINE ARE ALSO POSSIBLE AS THE CONVECTIVE LINE ENTERS THE MORE UNSTABLE AIRMASS. MVFR/IFR CONDITIONS WILL BE POSSIBLE IN THE VICINITY OF ANY SOWERS/THUNDERSTORMS. DRYING AND IMPROVING CONDS EXPECTED AFTER 03-06Z/12...AND VFR CONDS FOR SUN/MON...THEN DETERIORATING CONDITIONS ONCE AGAIN MON NIGHT INTO TUE. && .MARINE... COLD FRONT WILL CONTINUE TO CROSS THE REGION THIS AFTERNOON...CROSSING THE WATERS EARLY THIS EVENING. SLY WINDS WILL INCREASE TO 20-25 KT OVER THE BAY AND 25-30 KT OVER THE COASTAL WATERS IN ADVANCE OF THE FRONT...BEFORE BACKING TO THE W LATE THIS EVENING POST FRONTAL. LINE OF STRONG THUNDERSTORMS WILL ACCOMPANY THE FRONT...WHICH WILL LIKELY MIX DOWN STRONGER WINDS ALOFT. MAIN THREAT WILL BE WINDS IN EXCESS OF 34 KT...BUT ISOLATED WATER SPOUTS WILL ALSO BE POSSIBLE. SEAS WILL CONTINUE TO BUILD GENERALLY TO 5-8 FT (9-10 FT 20 NM OUT) THRU EARLY TONIGHT. BRIEF DOWNTURN IN WINDS EXPECTED IMMEDIATELY FOLLOWING THE FRONT THIS EVENING...BUT WLY WINDS WILL INCREASE RAPIDLY BACK TO SCA SPEEDS AND PERSIST THROUGH OVERNIGHT. SEAS WILL REMAIN 5-8 FT. HIGH PRESSURE BUILDS OVER THE GULF STATES TONIGHT-SUN MORNING...EXTENDING INTO THE MID-ATLANTIC REGION. THIS WILL ALLOW THE GRADIENT TO RELAX AND SCA SPEEDS TO SUBSIDE. SCA HEADLINES WILL REMAIN IN EFFECT THRU SUN MORNING. SEAS WILL REMAIN 4-6 FT THROUGH SUN AFTERNOON. HIGH PRESSURE WILL PUSH OFF THE SE COAST SUN NIGHT-MON AS SLY FLOW RETURNS TO THE WATERS. GRADIENT TIGHTENS OVER THE WATER MON NIGHT-TUES...WITH SLY WINDS INCREASING TO NEAR 15 KT. SEAS WILL ALSO BUILD TO 5+ FT IN THE NRN COASTAL WATERS. COLD FRONT WILL THEN CROSS THE WATERS MON NIGHT-TUES MORNING TIME FRAME...WITH ANOTHER STRONGER FRONT CROSSING THE WATERS WED. && .TIDES/COASTAL FLOODING... INCRSG S WNDS TO 20 TO 30 MPH TDA AHD OF APPROACHING CDFNT HAS PUSHED WATER LEVELS UP OVR PORTIONS OF THE CNTRL CHES BAY...MNLY INVOF LWR MD ERN SHORE (DORCHESTER TO SOMERSET COUNTIES) AND ALG THE NORTHERN SHORE OF ACCOMACK COUNTY IN VA. XPCG WTR LEVELS FOR HI TIDES THROUGH THIS AFTN TO BE ABT 1 TO 1.5 FT ABV NRML...PTNTLLY REACHING 3 FT MLLW AT CAMBRIDGE (MINOR FLOODING 3.5 FT MLLW) AND BISHOPS HEAD MD (MINOR FLOODING 3.2 FT MLLW)...THEN DEPARTURES AVGG 0.5 TO 1 FT ABV NRML FOR THE HIGH TIDE TNGT IN THOSE AREAS. && .CLIMATE... RECORD HIGH TEMPERATURE FOR THE DATE TIED AT SBY (1975). && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...NONE. NC...NONE. VA...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EST SUNDAY FOR ANZ635>637. SMALL CRAFT ADVISORY UNTIL 10 AM EST SUNDAY FOR ANZ630>634-638. SMALL CRAFT ADVISORY UNTIL 4 PM EST SUNDAY FOR ANZ650-652-654- 656-658. && $$ SYNOPSIS...MAM NEAR TERM...MAM SHORT TERM...JDM/MAM LONG TERM...SAM AVIATION...ALB/DAP MARINE...SAM TIDES/COASTAL FLOODING... CLIMATE...
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
339 PM EST SAT JAN 11 2014 .SYNOPSIS... A COLD FRONT CROSSES THE AREA LATE TODAY. HIGH PRESSURE RETURNS FROM THE WEST TONIGHT INTO SUNDAY. ANOTHER COLD FRONT APPROACHES FROM THE WEST LATE MONDAY. && .NEAR TERM /THROUGH TONIGHT/... RADAR MOSAIC INDICATING LEADING EDGE OF SQUALL LINE MOVING A BIT QUICKER THAN PROGGED EVEN BY FASTEST HRRR SOLUTION. HAVE ACCORDINGLY MOVED SHRAS OUT A BIT FASTER WITH LATEST FORECAST PACKAGE. LATEST WEATHER ANALYSIS SHOWS ERODING WEDGE FRONT NOW JUST WEST OF RIC METRO...EXTENDING SOUTH INTO THE WESTERN CAROLINAS. VIA SPC MESOANALYSIS, LEADING EDGE OF CONVECTION NOW CROSSING INTO WESTERN EDGE OF TOR WATCH BOX...IN EFFECT FOR SE VA /HAMPTON ROADS AND TIDEWATER/ AND NE NC UNTIL 01Z. LATEST WX ANALYSIS SHOWS APPROACHIGN COLD FRONT CURRENTLY PUSHING INTO WESTERN VA AT 20Z. AS EXPECTED, SEEING A NARROW LINE OF FORCED LOW TOPPED CONVECTION OVER EASTERN VA ATTM. PER SPC MESOANALYSIS, MLCAPE ON THE ORDER OF 500-1000 J/KG OVER THE WARM SECTOR (ALONG WITH 50-70 KT OF 0-6KM SHEAR AND LOW/MIDLVL LAPSE RATES OF 6-7 C/KM) HAS PROVED SUFFICIENT TO MIX DOWN STRONG 60-80KT WINDS JUST ABOVE THE DECK (AKQ VWP SHOWING SW WINDS ~60KT BETWEEN 1-2KFT UP). AS CONVECTIVE LINE ROLLS EAST, EXPECT DAMAGING WIND THREAT TO CONTINUE ACROSS THE SE THROUGH EARLY EVENING. ONCE THE COLD FRONT CLEARS THE AREA THIS EVENING...DRIER AIR RETURNS TONIGHT WITH CLEARING SKIES. LOWS TONIGHT IN THE MID 30S TO MID 40S. && .SHORT TERM /SUNDAY THROUGH MONDAY/... SUNDAY LOOKS LIKE A TRANSITION DAY AS AN UPPER TROUGH PIVOTS OFFSHORE AND QUASI-ZONAL FLOW BRINGS A MOSTLY SUNNY SKY. WHILE NOT NEARLY AS MILD AS SATURDAY...MAXIMA REMAIN ~1 S.D. ABOVE NORMAL...CLIMBING INTO THE MID 50S TO NEAR 60. FLOW ALOFT BECOMES INCREASINGLY SW ON MONDAY...WITH GRADUALLY INCREASING HIGH CLOUDS LATER IN THE DAY AS AN UPPER LEVEL TROUGH BARRELS EASTWARD FROM THE PLAINS MONDAY INTO MONDAY NIGHT. WARM SW FLOW ALLOWS MAXIMA TO WARM BACK INTO THE UPR 50S TO LOW 60S. && .LONG TERM /MONDAY NIGHT THROUGH SATURDAY/... MEDIUM RANGE MODELS CONTINUE TO SHOW GENERAL AGREEMENT WITH AMPLIFIED...BUT PROGRESSIVE UPPER LEVEL PATTERN THRU THE EXTENDED PERIOD. LONGWAVE TROUGH WILL SLOWLY PROGRESS EWD OVER THE MIDWEST MON NIGHT-TUES MORNING AS ADDITIONAL SHORTWAVE ENERGY DIGS OVER THE NRN PLAINS INTO THE MIDWEST. LEADING ENERGY WILL LIFT FROM THE GULF STATES NEWD INTO THE MID-ATLANTIC REGION TUES. ECMWF REMAINS MORE AMPLIFIED WITH THE LEADING ENERGY THAN OTHER MODELS...RESULTING IN STRONGER SWLY FLOW AND RESULTANT MOISTURE ADVECTION INTO THE REGION. DIFFERENCES IN STRENGTH ALSO AFFECT PLACEMENT OF SFC LOW PRESSURE AND ATTENDANT WAVY FRONT OVER THE REGION. STRONGER ECMWF SOLUTION DEVELOP A WAVE ALONG THE FRONT OVER THE MID-ATLANTIC REGION WHILE THE WEAKER GFS QUICKLY PUSHES THE WEAK/WAVY FRONT OFFSHORE. TRENDED FORECAST TOWARD ECMWF BASED ON RUN TO RUN CONSISTENCY AND PV FIELDS (BETTER PLACEMENT OF SFC FEATURES WRT TO UPPER LEVEL FIELDS). WILL MAINTAIN CHANCE-HIGH END CHANCE POPS TUES MORNING-AFTERNOON...WITH PRECIP PUSHING OFFSHORE BY EARLY TUES NIGHT. MOISTURE REMAINS RATHER SHALLOW...AND WITH PROGRESSIVE NATURE OF THE SYSTEM...QPF AMOUNTS WILL GENERALLY BE LESS THAN ONE QUARTER OF AN INCH. MEANWHILE...ENERGY WILL CONTINUE TO DIG OVER THE MIDWEST INTO THE GULF STATES TUES INTO TUES NIGHT. ADDITIONAL SFC PATTERN PROBLEMS ARISE...MAINLY WITH THE PLACEMENT OF THE SFC LOW. HOWEVER...MODELS BOTH INDICATING A COLD FRONT WILL CROSS THE AREA WEDS. LEADING VORTICITY MAXIMA WILL LIFT FROM THE GULF STATES INTO THE MID-ATLANTIC WEDS...WITH A WAVE POSSIBLY DEVELOPING ALONG THE FRONT OVER THE REGION. THIS COULD LEAD TO THE DEVELOPMENT OF A COASTAL LOW OFF THE MID-ATLANTIC COAST WEDS AFTERNOON. STRONG DYNAMICS LOOK TO OVERCOME LIMITED MOISTURE FOR PRECIP WEDS. HOWEVER...LOW CONFIDENCE DUE TO MODEL SPREAD WILL RESULT IN ONLY SLIGHT CHANCE-LOW END CHANCE POPS ATTM. RAIN/SNOW MIX WILL BE POSSIBLE EARLY WED ACROSS THE FAR NW ZONES. TROUGH AXIS WILL PUSH OFFSHORE WED NIGHT-THURS MORNING AS SFC HIGH PRESSURE BUILDS EWD OVER THE DEEP SOUTH...RIDGING NWD INTO THE LOCAL AREA. NRN STREAM WILL REMAIN ACTIVE AS ANOTHER SHORTWAVE DIGS OVER THE GREAT LAKES REGION LATE THURS-FRI...PUSHING A COLD FRONT ACROSS THE OH VALLEY INTO THE MID-ATLANTIC REGION FRI. COLD CANADIAN HIGH PRESSURE WILL BUILD OVER THE MIDWEST-GULF STATES FRI-SAT AS COLD AIR RETURNS TO THE REGION. PACIFIC ORIGIN OF THE COLD AIR WILL PREVENT THE EXTREME TEMPS SEEN IN THE PREVIOUS WEEK. HIGH TEMPS WILL WARM ABOVE NORMAL TUES (UPPER 50S-LOW 60S) BEFORE FALLING BACK TO SEASONABLE NORMS THRU THE END OF THE WEEK. HIGHS SAT EXPECTED IN THE UPPER 30S-LOW 40S. MILD MON NIGHT (LOW-MID 40S) BEFORE RETURNING TO NEAR OR SLIGHTLY ABOVE SEASONABLE LOWS (LOW-MID 30S) THRU THE EXTENDED. && .AVIATION /19Z SATURDAY THROUGH THURSDAY/... MAIN CONCERN FOR THE AFTN/EVNG IS THE CONVECTION AHEAD OF THE APPROACHING CDFNT. S WNDS HAVE INCREASED (20-25 KT) AND WILL BECOME GUSTY (30 KT) INTO THIS AFTN AS THE LINE MAKES ITS WAY EAST. TIMING OF SIGNIFICANT AREA OF PCPN ON RADAR HAS THE PRECIP THROUGH THE REGION FROM MID AFTN THROUGH 00-03Z/12. THERE IS A CHANCE FOR SCATTERED THUNDERSTORMS AHEAD OF THE LINE DUE TO STRONG LOW LEVEL WINDS AND THE WARM/MOIST AIRMASS OVER NE NC AND SE VA. THUNDER AND STRONGER WINDS(40-50 KT) ALONG THE LINE ARE ALSO POSSIBLE AS THE CONVECTIVE LINE ENTERS THE MORE UNSTABLE AIRMASS. MVFR/IFR CONDITIONS WILL BE POSSIBLE IN THE VICINITY OF ANY SOWERS/THUNDERSTORMS. DRYING AND IMPROVING CONDS EXPECTED AFTER 03-06Z/12...AND VFR CONDS FOR SUN/MON...THEN DETERIORATING CONDITIONS ONCE AGAIN MON NIGHT INTO TUE. && .MARINE... SSE WNDS PREVAIL OVR THE WTRS ATTM...AND WILL CONT TO INCRS THIS MRNG INTO THIS AFTN AHD OF APPROACHING CDFNT FM THE W. WNDS AT 925 MB INCRS TO ABT 50-60KT FM ABT 18-21Z/11...HWVR WAA AND COLD WTRS WILL LMT TRANSFER OF THOSE HIGHER SPDS TO THE WTR. SPDS INCRSG TO 20 TO 30 KT OVR THE WTRS BY THIS AFTN...KEEPING GUSTS BLO GALES (34 KT) FOR NOW...HWVR WOULD NOT RULE OUT A VERY SHORT PD LT THIS AFTN/EVE...ESP ACCOMPANYING CONVECTION...FOR GUSTS ABV GALES. WAVES ON THE BAY TO BUILD TO 3-5 FT...SEAS TO 6-10 FT THIS AFTN AND CONT INTO THE E. THE CDFNT PUSHES OFF THE CST AND E OF THE WTRS AFT MDNGT...SWINGING THE WNDS TO W. SFC HI PRES WILL BUILD E OVR SE CONUS TNGT- SUN...EXTENDING NWD OVER THE LOCAL AREA WTRS BY LT SUN MRNG/AFTN. THIS WILL ALLOW WINDSPEEDS TO DIMINISH AND SEAS/WAVES TO SUBSIDE. AS HI PRES PUSHES OFF THE SE CST SUN NGT...FLO RETURNS TO THE S. UNSETTLED CONDS WILL RETURN TO THE WTRS TUE-WED. SCAS RMNG UP FOR ALL WTRS THROUGH LT TNGT/SUN MRNG ON THE RIVERS/BAY AND SND...AND ON THE OCN THROUGH SUN AFTN. && .TIDES/COASTAL FLOODING... INCRSG S WNDS TO 20 TO 30 MPH TDA AHD OF APPROACHING CDFNT HAS PUSHED WATER LEVELS UP OVR PORTIONS OF THE CNTRL CHES BAY...MNLY INVOF LWR MD ERN SHORE (DORCHESTER TO SOMERSET COUNTIES) AND ALG THE NORTHERN SHORE OF ACCOMACK COUNTY IN VA. XPCG WTR LEVELS FOR HI TIDES LATE THIS MRNG THROUGH THIS AFTN TO BE ABT 1 TO 1.5 FT ABV NRML...PTNTLLY REACHING 3 FT MLLW AT CAMBRIDGE (MINOR FLOODING 3.5 FT MLLW) AND BISHOPS HEAD MD (MINOR FLOODING 3.2 FT MLLW)...THEN DEPARTURES AVGG 0.5 TO 1 FT ABV NRML FOR THE HIGH TIDE TNGT IN THOSE AREAS. && .CLIMATE... RECORD HIGH TEMPERATURE FOR THE DATE TIED AT SBY (1975). && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...NONE. NC...NONE. VA...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EST SUNDAY FOR ANZ635>637. SMALL CRAFT ADVISORY UNTIL 10 AM EST SUNDAY FOR ANZ630>634-638. SMALL CRAFT ADVISORY UNTIL 4 PM EST SUNDAY FOR ANZ650-652-654- 656-658. && $$ SYNOPSIS...MAM NEAR TERM...MAM SHORT TERM...JDM/MAM LONG TERM...SAM AVIATION...ALB/DAP MARINE...ALB/SAM TIDES/COASTAL FLOODING... CLIMATE...
AREA FORECAST DISCUSSION
NWS BILLINGS MT
908 AM MST SAT JAN 11 2014 .UPDATE... FORECAST REMAINS ON TRACK THIS MORNING...THEREFORE ONLY MINOR CHANGES MADE. INSPECTION OF MESOSCALE MODELS THIS MORNING...INCLUDING THE HRRR AND SSEO...CONFIRM THE FORECAST THINKING OF STRONG WINDS FOR LIVINGSTON TO BIG TIMBER TO HARLOWTON WHERE HIGHLIGHTS ARE ALREADY IN PLACE. FURTHERMORE...THESE MODELS PRODUCE STRONG WINDS ON THE MOUNTAINS ABOVE RED LODGE...AND SHOW SOME HINTS OF MOUNTAIN WAVE ACTIVITY BRINGING STRONGER WINDS INTO LOWER ELEVATIONS OF CARBON COUNTY. ANOTHER AREA OF CONCERN FOR STRONG WINDS THIS AFTERNOON AND EVENING IS THE FORT SMITH AREA AND LOCATIONS IN THE BIG HORN MOUNTAINS. HAVE INCREASED WINDS THERE BASED ON MAGNITUDE OF 700 MB WINDS COMING ACROSS AND INDICATIONS FROM HIGH RES MODELS. CHURCH && .SHORT TERM...VALID FOR TDY AND SUN... MAIN FORECAST CHALLENGE FOR THE SHORT-TERM PERIOD CONTINUES TO BE WINDS. INHERITED A WIND ADVISORY FOR GAP FLOW AREAS AND BIG TIMBER...HIGH WIND WATCH FOR RED LODGE FOR MOUNTAIN WAVES...AND HIGH WIND WATCH FOR WHEATLAND AND JUDITH GAP. PATTERN FEATURES A JET MOVING INTO THE AREA TODAY USHERING SHORTWAVE ENERGY INTO THE AREA LATE TODAY THROUGH SUN WHEN ANOTHER JET MOVES IN FROM BC AND THE PACIFIC NW. THIS FAST FLOW WILL BRING STRONG WINDS ALOFT TO THE REGION WITH 700 MB WINDS RANGING FROM 50 TO 75 KT THROUGH THE PERIOD. THE STRONGEST WINDS WERE FORECAST TO GET CLOSEST TO THE SURFACE ON SUN MORNING ACROSS THE AREA. SUN ALSO LOOKED LIKE THE PERIOD WITH THE BEST MIXING POTENTIAL BASED ON BUFKIT...BUT LIFT FROM THE DYNAMICS WILL HINDER THE MIXING DOWN OF THE STRONGEST WINDS. REGARDING THE SURFACE GRADIENT...IT LOOKED THE MOST SUPPORTIVE FOR GAP WINDS THIS MORNING...THEN TURNED MORE SW TO NE THROUGH SUN NIGHT. THE GRADIENT ORIENTATION DID NOT SUPPORT STRONG WINDS IN WHEATLAND COUNTY...HOWEVER THERE WILL PROBABLY BE ENOUGH MIXING FOR THIS AREA TO REACH HIGH WIND CRITERIA AT TIMES. OPTED TO GO WITH A HIGH-END WIND ADVISORY FOR THE GAP AREAS AND BIG TIMBER. THIS CAN ALWAYS BE UPGRADED TO A WARNING IN LATER PERIODS IF NEEDED. WILL GO WITH A HIGH WIND WARNING FOR JUDITH GAP AND WHEATLAND COUNTY. REGARDING RED LODGE...NOT ALL THE FACTORS WERE PRESENT FOR A MOUNTAIN WAVE...HOWEVER THERE WAS GOOD SUBSIDENCE...MOUNTAIN TOP STABILITY AND STRONG WIND. THUS WILL GO WITH A WARNING THERE AND EMPHASIZE STRONG WIND IN THE MOUNTAINS ABOVE RED LODGE. MADE A FEW ADJUSTMENTS TO POPS THROUGH THE PERIOD BASED ON LATEST MODEL MOISTURE FIELDS. WILL NOT MENTION FREEZING RAIN THIS MORNING AS TEMPERATURES WERE REMAINING CLOSE TO FREEZING AND THE SSEO DID NOT SUPPORT A GOOD CHANCE OF FREEZING RAIN. WILL KEEP HIGH POPS IN THE MOUNTAINS PER PREVIOUS FORECAST. A WARM FRONT WILL MOVE THROUGH THE E TODAY ALLOWING TEMPERATURES TO REACH THE 40S TO AROUND 50 DEGREES. A COLD FRONT LATER TODAY AND A SECOND FRONT ON SUN WILL BRING COOLER WEATHER TO THE REGION. MADE ONLY SLIGHT TEMPERATURE ADJUSTMENTS TODAY TO TREND BETTER FROM YESTERDAY/S READINGS. ARTHUR .LONG TERM...VALID FOR MON...TUE...WED...THU...FRI... PRESSURE GRADIENTS ENSURING WINDY CONDITIONS WILL IN PLACE THROUGHTHE EXTENDED WITH JET STREAM SUPPORT STRONGEST ON MONDAY BUT STILL POTENT TUESDAY AND WEDNESDAY BEFORE WANING LATER IN THE WEEK. FOR MONDAY ORIENTATION OF THE JET IS NOT QUITE AS FAVORABLE AS PREVIOUS RUNS INDICATED WHICH IS EVIDENT IN WEAKER SURFACE PRESSURE RISES. BUFKIT DATA SHOWS A LOT MORE ASCENT MONDAY AFTERNOON SO IT MAY BE TOUGH FOR VERY HIGH WINDS TO MATERIALIZE. HOWEVER THE 850 MB WINDS CONTINUE TO RUN IN THE 65 KT RANGE ACROSS THE REGION SO FORECAST DOES NOT HAVE TO CHANGE VERY MUCH FOR VERY STRONG WINDS TO MATERIALIZE. TUESDAY FAVORS GAP FLOW AREAS AND LESS ON THE PLAINS WITH PRESSURE FALLS BUT STILL MIXED GUSTS WILL KEEP BREEZY CONDITIONS AROUND. WEDNESDAY WILL HAVE TO BE WATCHED BECAUSE SOME STRONGER PRESSURE RISES MATERIALIZE AS A DEEP SURFACE LOW MOVES THROUGH SASKATCHEWAN. 700MB WINDS ARE VERY STRONG ACROSS SOUTHEAST MONTANA AND FOR SHERIDAN COUNTY SO WILL HAVE TO WATCH FOR PRESSURE RISES TO SUPPORT THE WINDS MIXING DOWN. THURSDAY AND FRIDAY HAVE A SLACKENING OF PRESSURE GRADIENTS WITH INCREASING WINDS AGAIN FOR SATURDAY. PRECIPITATION CHANCES LOOK BEST ON MONDAY DUE TO JET SUPPORT AND AN UNSTABLE ATMOSPHERE BUT DOWNSLOPE INFLUENCES WILL LIMIT PRECIP AMOUNTS IN WESTERN LOWER ELEVATIONS. BETTER CHANCES FOR SHOWERS WILL BE OVER SOUTHEAST MONTANA. LOOKS DRIER FOR MOST OF THE WEEK WITH PRECIPITATION LIMITED TO MOUNTAIN OROGRAPHICS. TEMPERATURES WILL CONTINUE TO BE ABOVE NORMAL THROUGH THE PERIOD WITH EROSION OF THE SNOWPACK BECOMING CRITICAL TO NIGHTTIME MINIMUM TEMPERATURES LATER IN THE WEEK. BORSUM && .AVIATION... SOUTHWEST WINDS WILL GUST TO 60KTS TODAY AT KLVM. WEST TO SOUTHWEST WINDS WILL GUST TO 50KTS FROM BIG TIMBER TO HARLOWTON. WINDS WILL INCREASE AT KBIL THIS AFTERNOON TOO WITH SOME GUSTS TO 25KTS. MOUNTAINS WILL BE OBSCURED WITH A STEADY STREAM OF MOISTURE PRODUCING SNOWFALL OVER THE WEST FACING SLOPES. OTHERWISE...VFR CONDITIONS ARE ANTICIPATED TODAY. TWH && .PRELIMINARY POINT TEMP/POPS... TDY SUN MON TUE WED THU FRI ------------------------------------------------------- BIL 045 034/043 032/048 035/046 030/050 026/039 023/041 2/J 21/N 02/W 31/N 11/N 11/N 11/B LVM 048 033/040 033/045 035/045 033/048 030/039 031/042 2/W 32/W 22/W 21/N 11/N 21/N 11/B HDN 043 027/040 024/044 027/041 023/047 019/035 013/036 2/J 22/W 23/W 31/N 11/N 11/B 11/B MLS 041 028/035 021/040 025/038 023/044 019/032 013/033 2/J 32/W 24/W 32/J 01/N 11/N 11/B 4BQ 043 028/036 024/043 026/040 024/048 021/034 015/036 2/J 22/W 24/W 32/J 01/N 11/N 11/B BHK 043 029/032 017/040 024/037 020/043 018/030 012/034 1/E 32/J 24/W 22/J 01/N 11/N 11/B SHR 048 025/038 021/043 026/044 023/050 020/038 017/042 0/N 22/W 22/W 31/N 11/U 11/B 11/B && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...HIGH WIND WARNING IN EFFECT UNTIL MIDNIGHT MST MONDAY NIGHT FOR ZONES 28-63. HIGH WIND WATCH IN EFFECT FROM MONDAY MORNING THROUGH MONDAY EVENING FOR ZONES 29-34-35-38-39-42-56-57. WIND ADVISORY IN EFFECT UNTIL 5 AM MST TUESDAY FOR ZONES 41-65-66. HIGH WIND WARNING IN EFFECT UNTIL 11 PM MST THIS EVENING FOR ZONE 56. WY...NONE. && $$ WEATHER.GOV/BILLINGS