Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 12/09/15


AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
955 AM MST MON DEC 7 2015 .UPDATE... ISSUED AT 934 AM MST MON DEC 7 2015 PTL PROFILER SHOWS THE INCREASING WESTERLY FLOW AROUND 700 MB BEHIND THE SHORTWAVE THAT HAS NOW MOVED OFF INTO NEBRASKA. HOW MUCH OF THIS FLOW MIXES DOWN ONTO THE PLAINS WILL BE ONE OF THE FORECAST ISSUES FOR TODAY. LATEST HRRR KEEPS THE WESTERLIES MAINLY NEAR THE FOOTHILLS AND ACROSS THE NORTHERN PORTIONS OF THE EASTERN PLAINS WITH A MORE SUBDUED S BECOMING SW FLOW OVER MOST OF THE REST OF THE PLAINS. THIS IS IN GENERAL AGREEMENT WITH THE LAST NAM. WILL HAVE TO KEEP AN EYE ON GUSTY WINDS IN THE FOOTHILLS OTHERWISE WIND FORECASTS AND THE REST OF TODAYS GRIDS LOOK GOOD. AREAS OF CLOUDINESS MOVING WITH THE FLOW WITH A GENERAL INCREASE TONIGHT AHEAD OF ANOTHER WEAK FAST MOVING WAVE. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 453 AM MST MON DEC 7 2015 SHORTWAVE TROUGH AXIS IS PAST AND THE WAVE SHAPED HAS CHANGED. STRONGEST WINDS APPEAR TO HAVE SHIFTED BACK TO THE HIGHER MOUNTAIN SLOPES. STILL POCKETS OF WIND MIXING DOWN ALONG THE LOWER FOOTHILLS BUT NOTHING LIKE A FEW HOURS AGO WHEN THERE WAS A MORE AMPLIFIED WAVE. EXPECT THIS WILL BE THE PATTERN FOR THE DAY WITH A BIT OF A DECREASE IN SPEEDS BY AFTERNOON. MEANWHILE MOISTURE IS SPREADING BACK ACROSS THE AREA AFTER A BREAK IN THE STRONG SUBSIDENCE BEHIND THE TROUGH AXIS WITH THE WAVE CLOUD REDEVELOPING. LOTS OF HIGH LEVEL MOISTURE UPSTREAM NOW...MAYBE FOREVER...THOUGH MODELS DO SHOW A BIT OF A BREAK IN THE CLOUDS AGAIN THIS EVENING. FLOW ALOFT INCREASES AGAIN WITH ANOTHER LITTLE RIPPLE IN THE FLOW BUT THE WAVE STRUCTURE LOOKS MARGINAL. SOME INCREASE IN SPEEDS FOR THE MOUNTAINS AND WITH A FAIRLY WELL MIXED AIRMASS...WE WILL PROBABLY SEE SOME SPILLAGE INTO THE ADJACENT WIND SPOTS. BUT THE PLAINS SHOULD JUST HAVE LIGHTER S-W WINDS ON THE RIDGES WITH NOT MUCH IN THE LOW SPOTS. I ADDED SOME MORE CLOUD COVER AND TAPERED TEMPS BACK A LITTLE THIS AFTERNOON FOR THE EXPECTED CLOUD COVER...BUT IT IS A WARM AIRMASS SO JUST A COUPLE DEGREES. MADE SOME MINOR ADJUSTMENTS TO TONIGHTS LOWS AS WELL...WARMER IN THE WINDIER AREAS AND A BIT LOWER ELSEWHERE...BUT THE CLOUD MAY REQUIRE A COUPLE MORE DEGREES OF WARMING. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 453 AM MST MON DEC 7 2015 THERE IS STRONG NORTHWESTERLY FLOW ALOFT ON TUESDAY WITH A JET MAXIMUM TO OUR IMMEDIATE NORTH AND NORTHEAST. THE NORTHWESTERLY FLOW ALOFT CONTINUES OVER THE CWA TUESDAY NIGHT INTO WEDNESDAY WITH AN UPPER RIDGE OVER THE WESTERN UNITED STATES. THE NORTHWESTERLY FLOW ALOFT INCREASES AGAIN LATER WEDNESDAY AND WEDNESDAY NIGHT AS A JET MAXIMUM MOVES IN BY WEDNESDAY NIGHT. THERE IS MAINLY DOWNWARD SYNOPTIC SCALE ENERGY PROGGED OVER THE CWA TUESDAY THROUGH WEDNESDAY. THE BOUNDARY LAYER FLOW IS DOMINATED BY DOWNSLOPING THROUGH THE PERIODS...DAY AND NIGHT. FOR MOISTURE...THERE IS A TAD IN THE MOUNTAINS TUESDAY INTO TUESDAY NIGHT THEN AGAIN WEDNESDAY EVENING...OTHERWISE THE CWA IS PRETTY DRY. THE QPF FIELDS SHOW A TAD OF MEASURABLE PRECIPITATION OVER THE NORTHWESTERN BORDER AREA OF THE CWA TUESDAY AND TUESDAY EVENING. WILL GO WITH SOME MINOR POPS IN THE HIGH MOUNTAINS TUESDAY AND TUESDAY NIGHT. THERE IS A BIT OF A MOUNTAIN WAVE SET UP TUESDAY AFTERNOON INTO WEDNESDAY MORNING. I DO NOT THINK HIGH WIND CRITERIA IS A THREAT AT THIS TIME...BUT IT WILL BE WINDY. FOR TEMPERATURES...TUESDAY`S HIGHS ARE 1-2 C WARMER THAN TODAY`S. WEDNESDAY`S HIGHS ARE UP A TAD AGAIN FROM TUESDAY`S. FOR THE LATER DAYS...THURSDAY THROUGH SUNDAY...MODELS HAVE STRONG FLOW ALOFT ON THURSDAY WITH A WEST-NORTHWESTERLY JET MAXIMUM ACROSS NORTHERN COLORADO. BY FRIDAY...THE MODELS AGAIN SHOW AN UPPER TROUGH OVER THE WESTERN UNITED STATES. NOW IT IS MUCH BROADER THAN YESTERDAY`S 00Z RUNS INDICATED. THE GFS BRINGS IT ACROSS COLORADO WITH A COUPLE PIECES OF ENERGY FRIDAY INTO SATURDAY MORNING. THE ECMWF NOW CLOSES OFF A CIRCULATION NEAR THE FOUR CORNERS MID DAY SATURDAY...THE GFS HAS THE TROUGH AXIS WELL EAST OF COLORADO AT THAT TIME. YESTERDAY`S 00Z MODEL RUNS WERE IN MUCH BETTER AGREEMENT WITH EACH OTHER. NOW THEY DO NOT AGREE AND THERE IS LESS CONSISTENCY WITH BOTH CONCERNING THEIR OWN PREVIOUS RUNS. THE ECMWF IS CONSIDERABLY SLOWER THAN THE GFS AT PRESENT. OH WELL...THERE WILL CERTAINLY BE A SLEW OF VARIOUS SOLUTIONS THE NEXT SEVERAL DAYS. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 934 AM MST MON DEC 7 2015 DENVER WINDS WILL BE TRICKY AT LEAST FOR AWHILE TODAY...RIGHT NOW MOST OF THE LLWAS SHOWING SOUTH WINDS AND MAY TREND TOWARDS MORE SW WITH TIME TODAY AND WILL ASSESS THIS. CLOSER TO THE FOOTHILLS AT BJC CHANCE THE WESTERLIES WILL BREAK THROUGH. && .BOU WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...SZOKE SHORT TERM...GIMMESTAD LONG TERM...RJK AVIATION...SZOKE
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
310 PM CST MON DEC 7 2015 .SHORT TERM...(Tonight) ISSUED AT 310 PM CST MON DEC 7 2015 Behind the weak boundary that moved through the area this morning, high pressure is building back into the Midwest. The narrow sfc ridge axis is slipping to the east and winds are picking up an increasingly southerly component. Unfortunately, not much of a change in the forecast in the wake of the weak wave. Dewpoints are still in the mid to upper 30s, with persistent fog. The high pressure and inversion aloft has trapped the low level moisture over the region for days now, and no mixing has occurred to scour it out. Whereas some areas have briefly improved visibilities this afternoon, the concern for the overnight hours is redevelopment. The fog clearing from west to east on sat imagery is largely a function of the sun. Earlier this morning, fog developed well back to the west into the stronger southerly winds through the overnight. May be a bit of a repeat with the dense fog, particularly in eastern Illinois. However, widespread fog is expected to develop to some extent for most of Central Illinois. Temps tonight will be relatively mild in the mid to upper 30s. && .LONG TERM...(Tuesday through Monday) ISSUED AT 310 PM CST MON DEC 7 2015 At least patchy fog will be in place across central and southeast Illinois to start the day Tuesday. Still some question regarding how widespread or thick it will be as southerly low-level flow will be increasing across the area during the morning hours. However, forecast soundings suggest a stout, near surface based, inversion that should help to keep moisture trapped near the ground. Hedged the temperatures toward things being a little cloudier/foggier, with highs mainly near 50. Several weak short waves will pass near the region in a quasi-zonal flow from Tuesday night into Friday. However, in addition to being weak, these waves will be lacking significant moisture and have generally limited PoPs to Slight Chance levels with their passage. A much stronger wave is still progged to impact the area over the weekend, and should be accompanied by period of heavier rainfall. At this point, the heaviest rainfall, and potential thunderstorms, is likely to occur later Saturday into Saturday night. However, model spread in the details is still significant, and confidence in the details is low. The current deterministic GFS and ECMWF forecasts are on the fast and slow sides respectively of their ensemble means. Have basically gone with a persistence forecast until forecast confidence grows to push it toward one model solution or another. Regardless of which model comes closest to verifying, it will get quite warm and humid (for December at least), with highs in the 60s and dew points in the 50s for Saturday. Cooler condtions come in to start next week behind the strong system, but temperatures should still be above normal for mid December. && .AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon) ISSUED AT 1212 PM CST MON DEC 7 2015 Persistent fog continues across PIA CMI and BMI. DEC and SPI slipping into IFR this morning, but VLIFR dominates the northern half of the state. Continuing it through the early afternoon...sun is slowly working through the fog and improving conditions to the west. Bigger concern will be the return of the fog tonight. GFS/NAM MOS and LAMP guidance is not dropping the vis tonight, but the HRRR and the fact that the llvl moisture is not going to be mixing out is leaning the forecast in a different direction. Will be a function of a brief wind maxima in the guidance that moves through overnight and how much in the way of cirrus remains over the region. && .ILX Watches/Warnings/Advisories... Dense Fog Advisory until 10 PM CST this evening for ILZ038- 043>046. && $$ SHORT TERM...HJS LONG TERM...BAK AVIATION...HJS
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
1221 PM CST MON DEC 7 2015 .UPDATE... ISSUED AT 1044 AM CST MON DEC 7 2015 High pressure ridge axis over Central Illinois this morning, with plenty of low level moisture trapped at the surface. Under the ridge with light winds last night, the high RH resulted in fog that is slow to burn off yet again this morning. Dense fog advisory is in place for much of ILXs CWA. Patchy improvement is finally starting to show with some reports, but automated observations are a bit behind the trend. Will be watching closely to make the decision as to whether or not an extension in time will be needed for the advisory. In addition, the thick fog has delayed the warm up this morning and have knocked the high temps down a degree or so. Only minor adjustments to the forecast here and there...for now. && .SHORT TERM...(Today) ISSUED AT 250 AM CST MON DEC 7 2015 Main forecast challenge in the short term will be coverage of fog and low cloud cover today and affect on afternoon temperatures. Latest surface analysis indicates the weak weather system that affected the area late yesterday afternoon and early evening with the light rain has shifted well off to our east early this morning. High pressure centered over northwest Missouri with the ridge axis extending north through east central Iowa into Wisconsin. The ridge axis by all models is forecast to shift across our area today. Quite a bit of low cloud cover and areas of fog have been noted along the ridge axis to our west with some of that is starting to edge into our northwest early this morning. RUC and NAM forecast soundings showing quite a bit of variability with respect to the low level inversion that is forecast to set up underneath the surface ridge axis today. Yesterday at this time, the NAM was quite aggressive with the inversion and the depth of the low level moisture trapped underneath it. However, this morning`s run was backing off on the depth of the moisture and strength of the low level inversion. Not seeing any strong reason for that to happen as the surface ridge should track slowly east-southeast across the region today with little in the way of significant flow noted on soundings until later today. If the last several runs of the HRRR are correct, the stratus and low visibilities will be with us through this afternoon. For that reason, will continue with a bit more pessimistic forecast with respect to cloud cover and temperatures this afternoon. Have undercut MAV guidance numbers by a category over most of our area this afternoon, with most of the highs closer to the cooler MET guidance. .LONG TERM...(Tonight through Sunday) ISSUED AT 250 AM CST MON DEC 7 2015 Mild week on tap for the forecast area, with upper flow expected to be of Pacific origin through the week. Latter part of the period looking especially mild, as 850 mb temperatures by Friday evening rise to near 10C. Highs in the 50s expected Tuesday-Wednesday before 60s start spreading in from the southwest. Widespread 60s expected by Saturday. Mostly dry weather expected through about Friday. Fast-moving upper wave expected to take much of its energy a bit further north of us Tuesday evening. An upper low is expected to close off within the wave, but the ECMWF stands alone in having this (and better precip chances) occur this far to the south; the remaining model suite has a further north solution. Thus, will keep chances in the "silent 20" range mainly northwest of I-55. The more robust rain chances are expected late in the week. A fast moving Canadian wave will dig southward into the Upper Mississippi Valley on Thursday and zip eastward. We should stay dry from this wave, but it will set the stage for a significant trough to dig southward west of the Rockies late this week, helping to produce the unseasonably mild temperatures. Unfortunately, there is a fairly wide model spread as to how much this second trough digs. The ECMWF continues to be much deeper as it draws energy from a Canadian wave moving through the northern Plains, resulting in fairly intense cyclogenesis over our area later in the weekend and an extended period of showers/isolated storms. The GFS is much more weak/ progressive and has the cold front east of us by Sunday morning. Still enough agreement to justify likely PoP`s Saturday night, but confidence wanes on Sunday. && .AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon) ISSUED AT 1212 PM CST MON DEC 7 2015 Persistent fog continues across PIA CMI and BMI. DEC and SPI slipping into IFR this morning, but VLIFR dominates the northern half of the state. Continuing it through the early afternoon...sun is slowly working through the fog and improving conditions to the west. Bigger concern will be the return of the fog tonight. GFS/NAM MOS and LAMP guidance is not dropping the vis tonight, but the HRRR and the fact that the llvl moisture is not going to be mixing out is leaning the forecast in a different direction. Will be a function of a brief wind maxima in the guidance that moves through overnight and how much in the way of cirrus remains over the region. && .ILX Watches/Warnings/Advisories... Dense Fog Advisory until 3 PM CST this afternoon for ILZ027>031- 036>038-040>048-051>057-061>063. && $$ UPDATE...HJS SHORT TERM...Smith LONG TERM...Geelhart AVIATION...HJS
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
528 AM EST MON DEC 7 2015 .SYNOPSIS... ISSUED AT 421 AM EST MON DEC 7 2015 WIDESPREAD FOG WILL CONTINUE TO DEVELOP OVER MUCH OF NORTHERN INDIANA AND FAR SOUTHWEST LOWER MICHIGAN AND EXTEND INTO NORTHWEST OHIO. EARLY MORNING TEMPERATURES WILL RANGE FROM THE UPPER 20S TO UPPER 30S WHERE CLOUDS LINGERED OVERNIGHT. THE NEXT CHANCE OF RAIN WILL ARRIVE LATE TUESDAY INTO WEDNESDAY. && .UPDATE... ISSUED AT 516 AM EST MON DEC 7 2015 HAVE ADDED 6 COUNTIES TO THE DENSE FOG ADVISORY. SKIES HAVE CLEARED OVER NEARLY ALL OF NORTHERN INDIANA AND NORTHWEST OHIO. DENSE FOG WAS DEVELOPING SOUTH AND EAST AND SHOULD DEVELOP/SPREAD INTO AREAS SOUTHWEST AND WEST OF FORT WAYNE INCLUDING WABASH AND COLUMBIA CITY. SOME LOW CLOUDS HAVE MOVED INTO LAPORTE AND BERRIEN COUNTIES AND MAY ACTUALLY HELP FOG TO LIFT A LITTLE. AT THIS TIME...WE ARE WATCHING COUNTIES ON THE EDGE OF THE ADVISORY INCLUDING GRANT...HUNTINGTON AND ALLEN INDIANA FOR POSSIBLE EXPANDING OF THE DENSE FOG ADVISORY. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 416 AM EST MON DEC 7 2015 THE COMBINATION OF RADIATION FOG AND ADVECTION FOG WAS MAKING THE FORECAST VERY CHALLENGING EARLY THIS MORNING. SKIES HAD CLEARED OVER FAR SOUTHWEST LOWER MICHIGAN AND NORTHERN INDIANA WHERE RADIATIONAL COOLING HAD ALLOWED FOG TO FORM. THE FOG WAS BECOMING MORE WIDESPREAD AND BECOMING LOCALLY DENSE WITH VISIBILITIES AROUND OR UNDER A QUARTER OF MILE. ADDITIONAL LOW CLOUDS AND SOME FOG WAS SPREADING SOUTHEAST OVER LAKE MICHIGAN AND SHOULD SPREAD INTO FAR SOUTHWEST LOWER MICHIGAN AND NORTHWEST INDIANA EARLY THIS MORNING. HAVE ISSUED A DENSE FOG ADVISORY FOR ALL OF FAR SOUTHWEST LOWER MICHIGAN AND NORTHWEST INDIANA...INTO THE NORTHERN PORTION OF NORTHWEST OHIO. THE TEMPERATURE IN SOME SPOTS WILL BE COLD ENOUGH FOR THE FOG TO BECOME FREEZING AND DEPOSIT A LIGHT FROST OR VERY LIGHT ICE LAYER. GIVEN LIMITED INSOLATION AND VERY LIGHT FLOW ALOFT...THE DENSE FOG WILL LIKELY PERSIST THROUGH MOST OF THE MORNING. OTHERWISE...CONDITIONS WILL IMPROVE THIS AFTERNOON WITH HIGHS ABOVE NORMAL OVER MOST AREAS. && .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 416 AM EST MON DEC 7 2015 FOCUS IN LONG TERM CONTINUES TO BE ON MID LEVEL AMPLIFICATION THROUGH THE PERIOD AND POSSIBLE RECORD SETTING TEMPERATURES BY THE WEEKEND ALONG WITH MODERATE TO HEAVY RAINFALL POTENTIAL. INITIALLY...WILL BE CAUTIOUSLY OPTIMISTIC THAT WIDESPREAD DENSE FOG WILL NOT BE AN ISSUE TO START THE PERIOD TUESDAY MORNING. SFC GRADIENT SHOULD BE INCREASING AS HIGH PRESSURE SLIDES EAST AND NEXT SHORT WAVE AND SFC TROUGH APPROACH FROM WEST. SOUNDINGS AND CROSS SECTIONS DO SHOW RESIDUAL MOISTURE SO MOSTLY CLOUDY TO START THE DAY. MIXING MAY ALLOW FOR PARTLY CLOUDY SKIES MID DAY BUT WILL QUICKLY GO BACK TO CLOUDY AS NEXT PACIFIC SHORT WAVE MOVES IN TUESDAY NIGHT INTO WEDNESDAY. IT STILL APPEARS ENOUGH MOISTURE AND WEAK LIFT TO SUPPORT LOW PCPN CHANCES FOR LIGHT SHOWERS WITH DECENT DPVA AND MODEST MOISTURE PROFILES. HIGHS WILL BE IN THE 40S DURING THIS PERIOD WITH LOWS IN THE UPPER 30S TO EVEN LOWER 40S WITH CLOUDS. THIS MID WEEK SYSTEM MARKS THE NOSE OF MUCH STRONGER JET ENERGY WHICH ORIGINATED OVER EAST ASIA LAST WEEK AND HAS FINALLY MADE ITS WAY OVER THE WESTERN CONUS. AN IMPRESSIVE 120-140 KT JET CORE STRETCHES OVER THE ENTIRE PACIFIC WITH 160+ KT EMBEDDED STREAKS PER MODELS. THIS ENERGY WILL CONTINUOUSLY DRIVE INLAND OVER WESTERN CONUS THIS WEEK...PROGRESSIVELY CARVING OUT A DEEP TROUGH IN THE SOUTHWEST. AS A RESULT...HEIGHTS WILL BUILD OVER THE MIDWEST AND STRENGTHENING LOW LEVEL JET WILL PUMP VERY WARM AND MOIST AIR INTO THE REGION BY LATE WEEK AND SETTING THE STAGE FOR POSSIBLE HEAVY RAINFALL. STILL A LOT OF UNCERTAINTY AND RUN TO RUN INCONSISTENCIES BETWEEN MODELS FOR MUCH ADDED FORECAST DETAILS. HOWEVER...PATTERN IS SUPPORTED BY MOST MODELS AND FITS THE LARGER EL NINO PATTERN. TEMPERATURES WILL REMAIN MILD THIS WEEK AND LOOK VERY WARM BY THE WEEKEND WITH GUIDANCE ALREADY POINTING TO POTENTIAL RECORD HIGHS IN THE 60S TO EVEN 70 IN OUR FAR SOUTH. CLOUDS AND RAIN WILL HAVE A LOT TO DO WITH HOW WARM WE ACTUALLY GET BUT POTENTIAL IS CERTAINLY THERE. ECMWF AND GFS ALSO DIFFER ON HOW ENERGY WILL EJECT OUT OF SOUTHWEST AND IMPACT US LOCALLY. GFS CONTINUES TO SHOW A COUPLED JET STRUCTURE BUT ECMWF BRINGS JET ENERGY OUT IN SEPARATED WAVES. REGARDLESS...POPS IN HIGH CHANCE TO LIKELY CATEGORY WARRANTED. HIGH PRECIPITABLE WATER VALUES OF 1-1.25 INCHES ALSO SHOWN BY GFS AND WILL BE NEAR RECORD TERRITORY FOR MID DECEMBER SO THREAT FOR HEAVY RAIN IS A POSSIBILITY. DETAILS AND TIMING WILL NEED TO BE SORTED OUT WITH TIME AS MORE OF THIS JET CORE COMES ONSHORE AND GETS SAMPLED BETTER. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 113 AM EST MON DEC 7 2015 HAVE MADE SIGNIFICANT CHANGES TO THE ONGOING TAFS WITH THE 06Z ISSUANCE. SOME LIMITED CLEARING WITH VERY WEEK FLOW AT THE SURFACE AND LOW LAYERS HAS ALREADY ALLOWED PATCHY DENSE FOG TO DEVELOP OVER NORTHERN INDIANA BEFORE 06Z. THE FOG WAS MUCH MORE WIDESPREAD OVER LOWER MICHIGAN AND TO A LESSER EXTENT NORTHEAST ILLINOIS. MOST TEMP/DEW POINT SPREADS WERE 3 DEGREES OR LESS. GIVEN THE LATEST OBSERVATIONS AND TRENDS AND GIVEN THE LATEST HIGH RESOLUTION NCEP/WPC ESPECIALLY THE HRRR AND ARW...EXPECT THE FOG TO DEVELOP AND BECOME DENSE BEFORE 12Z. GIVEN THE WEAK FLOW...LIMITED INSOLATION THE FOG WILL BE VERY SLOW TO LIFT...WITH LINGERING STRATUS LIKELY THIS AFTERNOON. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...DENSE FOG ADVISORY UNTIL 11 AM EST /10 AM CST/ THIS MORNING FOR INZ003>009-012>017-020-022>024. MI...DENSE FOG ADVISORY UNTIL 11 AM EST THIS MORNING FOR MIZ077>081. OH...DENSE FOG ADVISORY UNTIL 11 AM EST THIS MORNING FOR OHZ001-002- 004-005. LM...NONE. && $$ UPDATE...SKIPPER SYNOPSIS...AGD/SKIPPER SHORT TERM...SKIPPER LONG TERM...LASHLEY AVIATION...SKIPPER VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSNORTHERNINDIANA WWW.TWITTER.COM/NWSIWX WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
422 AM EST MON DEC 7 2015 .SYNOPSIS... ISSUED AT 421 AM EST MON DEC 7 2015 WIDESPREAD FOG WILL CONTINUE TO DEVELOP OVER MUCH OF NORTHERN INDIANA AND FAR SOUTHWEST LOWER MICHIGAN AND EXTEND INTO NORTHWEST OHIO. EARLY MORNING TEMPERATURES WILL RANGE FROM THE UPPER 20S TO UPPER 30S WHERE CLOUDS LINGERED OVERNIGHT. THE NEXT CHANCE OF RAIN WILL ARRIVE LATE TUESDAY INTO WEDNESDAY. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 416 AM EST MON DEC 7 2015 THE COMBINATION OF RADIATION FOG AND ADVECTION FOG WAS MAKING THE FORECAST VERY CHALLENGING EARLY THIS MORNING. SKIES HAD CLEARED OVER FAR SOUTHWEST LOWER MICHIGAN AND NORTHERN INDIANA WHERE RADIATIONAL COOLING HAD ALLOWED FOG TO FORM. THE FOG WAS BECOMING MORE WIDESPREAD AND BECOMING LOCALLY DENSE WITH VISIBILITIES AROUND OR UNDER A QUARTER OF MILE. ADDITIONAL LOW CLOUDS AND SOME FOG WAS SPREADING SOUTHEAST OVER LAKE MICHIGAN AND SHOULD SPREAD INTO FAR SOUTHWEST LOWER MICHIGAN AND NORTHWEST INDIANA EARLY THIS MORNING. HAVE ISSUED A DENSE FOG ADVISORY FOR ALL OF FAR SOUTHWEST LOWER MICHIGAN AND NORTHWEST INDIANA...INTO THE NORTHERN PORTION OF NORTHWEST OHIO. THE TEMPERATURE IN SOME SPOTS WILL BE COLD ENOUGH FOR THE FOG TO BECOME FREEZING AND DEPOSIT A LIGHT FROST OR VERY LIGHT ICE LAYER. GIVEN LIMITED INSOLATION AND VERY LIGHT FLOW ALOFT...THE DENSE FOG WILL LIKELY PERSIST THROUGH MOST OF THE MORNING. OTHERWISE...CONDITIONS WILL IMPROVE THIS AFTERNOON WITH HIGHS ABOVE NORMAL OVER MOST AREAS. && .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 416 AM EST MON DEC 7 2015 FOCUS IN LONG TERM CONTINUES TO BE ON MID LEVEL AMPLIFICATION THROUGH THE PERIOD AND POSSIBLE RECORD SETTING TEMPERATURES BY THE WEEKEND ALONG WITH MODERATE TO HEAVY RAINFALL POTENTIAL. INITIALLY...WILL BE CAUTIOUSLY OPTIMISTIC THAT WIDESPREAD DENSE FOG WILL NOT BE AN ISSUE TO START THE PERIOD TUESDAY MORNING. SFC GRADIENT SHOULD BE INCREASING AS HIGH PRESSURE SLIDES EAST AND NEXT SHORT WAVE AND SFC TROUGH APPROACH FROM WEST. SOUNDINGS AND CROSS SECTIONS DO SHOW RESIDUAL MOISTURE SO MOSTLY CLOUDY TO START THE DAY. MIXING MAY ALLOW FOR PARTLY CLOUDY SKIES MID DAY BUT WILL QUICKLY GO BACK TO CLOUDY AS NEXT PACIFIC SHORT WAVE MOVES IN TUESDAY NIGHT INTO WEDNESDAY. IT STILL APPEARS ENOUGH MOISTURE AND WEAK LIFT TO SUPPORT LOW PCPN CHANCES FOR LIGHT SHOWERS WITH DECENT DPVA AND MODEST MOISTURE PROFILES. HIGHS WILL BE IN THE 40S DURING THIS PERIOD WITH LOWS IN THE UPPER 30S TO EVEN LOWER 40S WITH CLOUDS. THIS MID WEEK SYSTEM MARKS THE NOSE OF MUCH STRONGER JET ENERGY WHICH ORIGINATED OVER EAST ASIA LAST WEEK AND HAS FINALLY MADE ITS WAY OVER THE WESTERN CONUS. AN IMPRESSIVE 120-140 KT JET CORE STRETCHES OVER THE ENTIRE PACIFIC WITH 160+ KT EMBEDDED STREAKS PER MODELS. THIS ENERGY WILL CONTINUOUSLY DRIVE INLAND OVER WESTERN CONUS THIS WEEK...PROGRESSIVELY CARVING OUT A DEEP TROUGH IN THE SOUTHWEST. AS A RESULT...HEIGHTS WILL BUILD OVER THE MIDWEST AND STRENGTHENING LOW LEVEL JET WILL PUMP VERY WARM AND MOIST AIR INTO THE REGION BY LATE WEEK AND SETTING THE STAGE FOR POSSIBLE HEAVY RAINFALL. STILL A LOT OF UNCERTAINTY AND RUN TO RUN INCONSISTENCIES BETWEEN MODELS FOR MUCH ADDED FORECAST DETAILS. HOWEVER...PATTERN IS SUPPORTED BY MOST MODELS AND FITS THE LARGER EL NINO PATTERN. TEMPERATURES WILL REMAIN MILD THIS WEEK AND LOOK VERY WARM BY THE WEEKEND WITH GUIDANCE ALREADY POINTING TO POTENTIAL RECORD HIGHS IN THE 60S TO EVEN 70 IN OUR FAR SOUTH. CLOUDS AND RAIN WILL HAVE A LOT TO DO WITH HOW WARM WE ACTUALLY GET BUT POTENTIAL IS CERTAINLY THERE. ECMWF AND GFS ALSO DIFFER ON HOW ENERGY WILL EJECT OUT OF SOUTHWEST AND IMPACT US LOCALLY. GFS CONTINUES TO SHOW A COUPLED JET STRUCTURE BUT ECMWF BRINGS JET ENERGY OUT IN SEPARATED WAVES. REGARDLESS...POPS IN HIGH CHANCE TO LIKELY CATEGORY WARRANTED. HIGH PRECIPITABLE WATER VALUES OF 1-1.25 INCHES ALSO SHOWN BY GFS AND WILL BE NEAR RECORD TERRITORY FOR MID DECEMBER SO THREAT FOR HEAVY RAIN IS A POSSIBILITY. DETAILS AND TIMING WILL NEED TO BE SORTED OUT WITH TIME AS MORE OF THIS JET CORE COMES ONSHORE AND GETS SAMPLED BETTER. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 113 AM EST MON DEC 7 2015 HAVE MADE SIGNIFICANT CHANGES TO THE ONGOING TAFS WITH THE 06Z ISSUANCE. SOME LIMITED CLEARING WITH VERY WEEK FLOW AT THE SURFACE AND LOW LAYERS HAS ALREADY ALLOWED PATCHY DENSE FOG TO DEVELOP OVER NORTHERN INDIANA BEFORE 06Z. THE FOG WAS MUCH MORE WIDESPREAD OVER LOWER MICHIGAN AND TO A LESSER EXTENT NORTHEAST ILLINOIS. MOST TEMP/DEW POINT SPREADS WERE 3 DEGREES OR LESS. GIVEN THE LATEST OBSERVATIONS AND TRENDS AND GIVEN THE LATEST HIGH RESOLUTION NCEP/WPC ESPECIALLY THE HRRR AND ARW...EXPECT THE FOG TO DEVELOP AND BECOME DENSE BEFORE 12Z. GIVEN THE WEAK FLOW...LIMITED INSOLATION THE FOG WILL BE VERY SLOW TO LIFT...WITH LINGERING STRATUS LIKELY THIS AFTERNOON. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...DENSE FOG ADVISORY UNTIL 11 AM EST /10 AM CST/ THIS MORNING FOR INZ003>009-012>016-020. MI...DENSE FOG ADVISORY UNTIL 11 AM EST THIS MORNING FOR MIZ077>081. OH...DENSE FOG ADVISORY UNTIL 11 AM EST THIS MORNING FOR OHZ001-002. LM...NONE. && $$ SYNOPSIS...AGD/SKIPPER SHORT TERM...SKIPPER LONG TERM...LASHLEY AVIATION...SKIPPER VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSNORTHERNINDIANA WWW.TWITTER.COM/NWSIWX WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
321 AM EST MON DEC 7 2015 .UPDATE... THE LONG TERM AND AVIATION SECTIONS HAVE BEEN UPDATED BELOW && .SYNOPSIS... ISSUED AT 211 PM EST SUN DEC 6 2015 A SERIES OF UPPER WAVES WILL BRING SMALL RAIN CHANCES TO CENTRAL INDIANA TONIGHT AND AGAIN WEDNESDAY. THEN...A DEEP UPPER TROUGH WILL SET UP OVER THE SOUTHWESTERN STATES. DISTURBANCES WILL EJECT NORTHEASTWARD AROUND THE BASE OF THE UPPER TROUGH AND THROUGH THE OHIO VALLEY. ALSO...A FRONTAL SYSTEM WILL APPROACH FROM THE WEST. THESE FEATURES WILL INTERACT WITH INCREASING AMOUNTS OF MOISTURE TO BRING PROLONGED RAIN CHANCES TO ALL OF CENTRAL INDIANA LATE NEXT WEEK AND NEXT WEEKEND. TEMPERATURES WILL START OFF SLIGHTLY ABOVE NORMAL WITH HIGHS IN THE MID TO UPPER 40S MONDAY. IT WILL BECOME EVEN MORE MILD LATER IN THE WEEK AND NEXT WEEKEND WITH AFTERNOON HIGHS IN THE LOWER 60S POSSIBLE BY SATURDAY. && .NEAR TERM /REST OF TONIGHT/... ISSUED AT 746 PM EST SUN DEC 6 2015 0030Z UPDATE...MAIN UPDATE EARLY THIS EVENING WAS TO INCREASE THE COVERAGE FOR LIGHT RAIN SHOWERS EARLY THIS EVENING BASED ON LATEST RADAR MOSAIC AND HRRR SOLUTION. THIS INCREASES THE POPS ACROSS SOME OF THE NORTHERN COUNTIES THROUGH THIS EVENING BEFORE THE BETTER LIFT AND MOISTURE MOVES SOUTH OF THE AREA. OTHER MINOR UPDATES WERE MADE TO ACCOUNT FOR THE LATEST IN TEMP/DEW POINT/WIND DIR/SPEED TRENDS. ZFPIND AND ASSOCIATED FORECAST PRODUCTS ALREADY. PREVIOUS DISCUSSION FOLLOWS. POPS WILL BE THE MAIN FOCUS TONIGHT AS AN UPPER LOW MOVES THROUGH THE ZONAL FLOW ALOFT AND TRACKS ACROSS THE INDIANA-MICHIGAN BORDER. WATER VAPOR LOOP WAS SHOWING THE UPPER LOW SPINNING ACROSS SOUTHEASTERN IOWA THIS AFTERNOON. THE MODELS ARE CLOSE AND BRING THE CENTER OF THE LOW TO NORTHEASTERN ILLINOIS BY 00Z TONIGHT AND TO WESTERN PARTS OF LAKE ERIE 12Z MONDAY. THE 12Z GFS...NAM AND GEM HAD ALL THE QPF NEAR AND SOUTH OF INTERSTATE 70...WHEREAS THE 00Z ECMWF HAD IT FURTHER NORTH ACROSS MUCH OR ALL OF CENTRAL INDIANA. THIS SEEMS TO GO ALONG THE FORMER MODELS BEING MORE COMPACT AND FURTHER SOUTH WITH THE HIGHER 1000-500 MILLIBAR RH BULLSEYE. WILL GO WITH THE MAJORITY AND KEEP CHANCE POPS SOUTH AND TRANSITION TO DRY ACROSS THE NORTHERNMOST TIER OR TWO. THE RAIN SHOWERS SHOULD BE ENDING FROM WEST TO EAST OVERNIGHT. WITH LOW STRATOCU DECK AROUND...PREFER THE WARMER 12Z GFS AND ENSEMBLE MOS. THE WET BULB ZERO TEMPERATURE SHOULD STAY JUST ABOVE FREEZING...SO DO NOT THINK WE WILL SEE A MIX OR CHANGEOVER OF THE RAIN SHOWERS TO SNOW SHOWERS. ALSO...SOME UPSTREAM LOW VISIBILITIES WERE SEEN IN THE SURFACE OBS ACROSS MISSOURI AND IOWA EARLY THIS AFTERNOON...SO WILL INCLUDE PATCHY FOG. && .SHORT TERM /MONDAY THROUGH WEDNESDAY/... ISSUED AT 211 PM EST SUN DEC 6 2015 MAIN CHALLENGE TO THE SHORT TERM WILL BE POPS AND CLOUD COVER AS MODELS HAVE A PAIR OF UPPER WAVES MOVING THROUGH THE VICINITY THROUGH WEDNESDAY. MODELS ARE HAVING DIFFERENCES WITH TIMING AND LOCATION WITH THESE FEATURES...WHICH MANY TIMES IS THE CASE IN DISTURBANCES MOVING THROUGH FAST ZONAL FLOW. THE WORK WEEK SHOULD START OFF WITH LINGERING STRATUS AND PATCHY FOG AS THE UPPER LOW MOVES TO WESTERN PARTS OF LAKE ERIE. MODEL SOUNDINGS SUGGEST STRONG INVERSION SHOULD KEEP AT LEAST SOME STRATOCU AROUND...AND LOCAL TRAPPING FLOW CHART SUGGESTS CLOUDS WILL HANG AROUND UP TO 24 HOURS LONGER THAN MOS SUGGESTS. SO...WILL SHOOT FOR MOSTLY CLOUDY TOMORROW. THIS SHOULD ALSO KEEP TEMPERATURES FROM HITTING 50 DEGREES DESPITE NICE LOW LEVEL THERMAL SETUP. THE 12Z GFS...CANADIAN AND NAM ARE THEN MUCH STRONGER AND FASTER AND FURTHER NORTH BRINGING AN UPPER WAVE OVER THE GREAT LAKES MONDAY NIGHT. THE 00Z ECMWF DOES NOT BRING THE WAVE ACROSS UNTIL TUESDAY AND BRINGS IT ACROSS THE OHIO VALLEY. EITHER WAY...MOISTURE IS LACKING SO...WILL NOT HAVE POPS MONDAY NIGHT OR TUESDAY. BY TUESDAY...THE LOWER LEVELS DRY ENOUGH THAT THERE SHOULD BE SOME SUNSHINE AROUND AFTER MORE MORNING STRATUS. LOW LEVEL THERMAL PROGS AND SOME SUNSHINE SUGGEST TEMPERATURES SHOULD BE A FEW DEGREES WARMER ON TUESDAY WITH MOS BLEND OF UPPER 40S TO LOWER 50S. THE LAST WAVE OF CONCERN SHOULD MOVE THROUGH THE OHIO VALLEY AND GREAT LAKES ON WEDNESDAY. THE 12Z NAM LOOKS TO BE THE ODD ONE OUT BEING MUCH FURTHER NORTH. WITH INCREASING SOUTHWESTERLY FLOW OVER THE AREA ON THE BACK SIDE OF AN EAST COAST HIGH...WILL SEE INCREASING MOISTURE TO GO ALONG WITH DECENT FORCING. THUS...AT LEAST CHANCE POPS FOR RAIN SHOWERS LOOK GOOD ACROSS ALL OF CENTRAL INDIANA ON WEDNESDAY. THE CLOUDS WILL KEEP TEMPERATURES FROM FALLING MUCH TUESDAY NIGHT WITH LOWS IN THE UPPER 30S TO LOWER 40S. THE CLOUDS AND SHOWERS SHOULD ALSO KEEP TEMPERATURES FROM RISING TOO MUCH WEDNESDAY WITH HIGHS IN THE UPPER 40S AND LOWER 50S. && .LONG TERM /THURSDAY THROUGH SUNDAY/... ISSUED AT 321 AM EST MON DEC 7 2015 WEATHER PATTERN WILL BECOME INCREASINGLY ACTIVE THROUGH THE EXTENDED AS A DEEP MERIDIONAL UPPER TROUGH AMPLIFIES OVER THE WESTERN U S AND PROGRESSES EAST OVER THE WEEKEND. QUASI-ZONAL FLOW INITIALLY WILL TRANSITION TO A BROAD RIDGING BY SATURDAY OVER MUCH OF THE EASTERN HALF OF THE COUNTRY...RESULTING IN UNSEASONABLY MILD TEMPERATURES THROUGH MUCH OF THE PERIOD. FIRST PART OF THE EXTENDED WILL BE GENERALLY QUIET WITH THE POTENTIAL FOR JUST A FEW SHOWERS THURSDAY NIGHT INTO FRIDAY AS LOW PRESSURE TRACKS THROUGH THE UPPER GREAT LAKES. BULK OF THE FORCING ALOFT ASSOCIATED WITH THIS FEATURE WILL REMAIN DISPLACED TO THE NORTHWEST...BUT PRESENCE OF A WEAK BOUNDARY SOUTH INTO THE FORECAST AREA SHOULD BE ENOUGH TO GENERATE A FEW SHOWERS. THE REMNANT BOUNDARY WILL STALL ACROSS THE OHIO VALLEY FRIDAY BEFORE GETTING PICKED UP AND SHIFTED NORTH AS LOW PRESSURE ORGANIZES OVER THE SOUTHERN PLAINS. STRONG SOUTHERLY FLOW ON THE BACK SIDE OF HIGH PRESSURE OFF THE SOUTHEAST COAST WILL DRAW PROGRESSIVELY DEEPER GULF MOISTURE INTO THE OHIO VALLEY FOR THE WEEKEND WITH INCREASING CHANCES FOR SHOWERS. EXTENDED MODELS HAVE LARGELY FLIPPED IN THEIR SOLUTIONS FROM RUNS SATURDAY...WITH THE ECMWF NOW DEVELOPING A RAPIDLY DEEPENING SURFACE LOW OVER THE REGION FOR LATE WEEKEND WHILE THE OP GFS MAINTAINS A MORE PROGRESSIVE AND WEAKER SOLUTION. ECMWF HAS SUPPORT FROM A NUMBER OF THE GFS ENSEMBLE MEMBERS AND THE SYSTEM STRENGTH ALONE ARGUES FOR CONVECTION IMPACTING THE FORECAST AREA SUNDAY/SUNDAY NIGHT. NOT READY JUST YET TO INTRODUCE ISOLATED THUNDER BUT IF TRENDS CONTINUE IN THE DIRECTION OF THE STRONGER SURFACE LOW...COULD CERTAINLY SEE A FEW THUNDERSTORMS ALONG THE FRONT. POTENTIAL IS THERE FOR WINDY AND SHOWERY CONDITIONS WITH IMPRESSIVE GULF MOISTURE PLUME ADVECTING INTO THE OHIO VALLEY BRINGING PRECIP WATER VALUES NEAR CLIMATOLOGICAL MAX LEVELS FOR MID DECEMBER. HIGHS WILL REMAIN MILD THROUGH MUCH OF THE PERIOD...WARMING INTO THE 60S FOR THE WEEKEND WITH STRONG SOUTHERLY FLOW AHEAD OF THE COLD FRONT. DRIER AND COOLER CONDITIONS WILL RETURN FOR EARLY NEXT WEEK AS THE STORM SYSTEM RAPIDLY MOVES AWAY TO THE NORTHEAST. && .AVIATION /DISCUSSION FOR THE 070900Z TAFS/... ISSUED AT 321 AM EST MON DEC 7 2015 LAST OF THE LIGHT RAIN SHOWERS ASSOCIATED WITH THE UPPER WAVE SHOULD BE CLEAR OF KIND NEAR OR SHORTLY AFTER 09Z. SKIES HAVE CLEARED RELATIVELY QUICKLY OVER THE NORTHERN WABASH VALLEY AND ALREADY SEEING RESTRICTIONS DEVELOP AS FOG FORMS. HITTING FOG AND LOWER CEILINGS HARDER INITIALLY AT BOTH KHUF AND KLAF OVER THE NEXT SEVERAL HOURS AND MAY NEED TO CONSIDER AT KBMG AND KIND AS WELL. CONFIDENCE REMAINS LOW IN THE PARTICULARS HOWEVER WITH POOR MODEL SUPPORT. 06Z DISCUSSION FOLLOWS. VFR INITIALLY WILL GIVE WAY TO MVFR OR WORSE RESTRICTIONS LATER TONIGHT INTO MONDAY. VERY LOW CONFIDENCE FORECAST HOWEVER AS VARIOUS GUIDANCE PRODUCTS DIFFER SIGNIFICANTLY IN THEIR HANDLING OF EXPECTED CONDITIONS AND CONDITIONS UPSTREAM VARY SIGNIFICANTLY. WILL GENERALLY TREND THINGS DOWN TO LOW END MVFR BY THE EARLY PART OF THE OVERNIGHT AND KEEP THEM THERE THROUGH EARLY AFTERNOON MONDAY AS GUIDANCE TYPICALLY CLEARS SKIES FAR TOO EARLY IN THESE SITUATIONS. WINDS WILL BE 5KT OR LESS THROUGHOUT THE PERIOD. && .IND WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SYNOPSIS...MK NEAR TERM...SMF/MK SHORT TERM...MK LONG TERM....RYAN AVIATION...NIELD
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
137 AM EST MON DEC 7 2015 .SYNOPSIS... ISSUED AT 113 AM EST MON DEC 7 2015 AREAS OF FOG ARE LIKELY EARLY THIS MORNING BUT THERE IS STILL SOME UNCERTAINTY AS TO EXACT COVERAGE AND HOW DENSE IT WILL BE. LOWS TONIGHT WILL BE AROUND 30 DEGREES. HIGHS TODAY WILL BE IN THE LOW TO MID 40S. THE NEXT CHANCE OF RAIN WILL ARRIVE LATE TUESDAY INTO WEDNESDAY. && .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 333 PM EST SUN DEC 6 2015 FOG AND STRATUS ONCE AGAIN THE PRIMARY CONCERN OF THE SHORT TERM PERIOD. UPPER LOW CURRENTLY APPROACHING OUR AREA AND WILL BRING INCREASING MIDLEVEL CLOUDS THIS EVENING. A FEW LIGHT RETURNS NOTED ON UPSTREAM RADAR BUT VERY FEW PRECIP REPORTS AT THE SURFACE. A STRAY SPRINKLE MAY BE POSSIBLE SOUTH OF US-30 LATE THIS EVENING BUT CHANCES FOR MEASURABLE RAIN APPEAR QUITE LOW GIVEN BEST CVA AND MOISTURE RETURN REMAIN SOUTH OF OUR CWA. WILL MAINTAIN JUST A SILENT 10 POP. MORE PRESSING CONCERN WILL BE POTENTIAL FOR ANOTHER ROUND OF FOG AND STRATUS IN THE WAKE OF PASSING LOW. UPSTREAM SATELLITE AND SURFACE OBS INDICATE A FAIRLY WIDESPREAD AREA OF LOW STRATUS AND BR ACROSS THE UPPER MIDWEST. MIDLEVEL CLOUDS EXPECTED TO EXIT BY 06-09Z AND RADIATIONAL COOLING WILL LIKELY SUPPORT FOG SPREADING INTO OUR AREA GIVEN LIGHT SURFACE WINDS. NAM FORECAST SOUNDINGS AND MOS GUIDANCE ARE SUPPORTIVE AND DID GO WITH AREAS OF FOG AFTER 06Z..BUT EXACT COVERAGE AND DENSITY REMAIN SOMEWHAT UNCERTAIN DUE TO COMPLICATIONS ASSOCIATED WITH PASSING HIGHER-BASED CLOUDS. COULD POTENTIALLY SEE ANOTHER ADVISORY BEING NECESSARY BUT REALLY WONT KNOW TRUE SCOPE OF THE EVENT UNTIL LATER TONIGHT. EXPECT LOWS AROUND 30 DEGREES SO SOME FREEZING FOG POSSIBLE BUT SHOULD BE WARMER THAN LAST NIGHT GIVEN EXPECTED CLOUD COVER AND WARMER START. HIGH TEMPERATURES ON MONDAY CURRENTLY EXPECTED TO BE IN THE LOW TO MID 40S BUT HIGH BUST POTENTIAL EITHER WAY DEPENDING ON DEGREE OF MORNING CLOUDS/FOG AND SUBSEQUENT SPEED OF DIURNAL MIX OUT. && .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 333 PM EST SUN DEC 6 2015 START OF THE PERIOD SHOULD BE DRY BUT MAY BE PLAGUED WITH YET ANOTHER WINDOW OF STRATUS (FOG?) INTO AT LEAST TUESDAY NIGHT AS INVERSION LOOKS TO RE-ESTABLISH. THIS DECK COULD POTENTIALLY MORE PROBLEMATIC WITH REGARDS TO DISSIPATION AS DEPTH OF CLOUDS MAY BE SUBSTANTIALLY MORE THAN PAST BOUT. HAVE TRENDED TOWARDS A MORE SUBSTANTIAL INCREASE IN CLOUDS INTO TUESDAY NIGHT WITH HINTS OF AT LEAST PARTIAL CLEARING TUESDAY AFTERNOON. GIVEN THESE CONCERNS...LITTLE IN THE WAY OF CHANGES TO TEMPERATURES HAS TAKEN PLACE. MODEL CONSENSUS CONTINUES TO SOME DEGREE AS WE HEAD TOWARDS THE WEEKEND WITH A STRONGER WAVE MOVING IN TUESDAY NIGHT INTO WEDS WITH AT LEAST A CHANCE OF MEASURABLE RAINFALL BUT STILL HOLDING IN CHC CATEGORY FOR NOW AS MOISTURE WILL STILL BE LIMITED AND AREA COULD BE SPLIT TO NORTH AND SOUTH. YET ANOTHER LOW WILL COME OUT OF THE PLAINS AND MAYBE BRING A CHANCE OF SHOWERS. WHAT WILL HAPPEN THIS SYSTEM IS THE START OF A DRAMATIC INCREASE IN SOUTHERLY FLOW INTO THE REGION...SETTING THE STAGE FOR POTENTIALLY MORE SUBSTANTIAL RAINFALL AND MUCH WARMER TEMPERATURES. TROUGH WILL DIG INTO THE WEST WITH A DEEP CLOSED LOW CUTTING OFF AND DRIFTING EAST INTO THE WEEKEND. A STATIONARY FRONT WILL LIKELY SETUP SOMEWHERE ACROSS THE FORECAST AREA STARTING AS EARLY AS SAT NGT IN A NE TO SW ORIENTATION WITH THE FIRST OF WHAT SHOULD BE 2 SURGES OF GULF MOISTURE. RAIN CHANCES WILL INCREASE DRAMATICALLY SAT NGT INTO SUNDAY WARRANTING HIGH CHC TO LIKELY POPS WITH EMPHASIS ON WEST/NW AREAS. TEMPERATURES WILL SHOOT WELL INTO THE 50S AND LIKELY SOME 60S BY SAT AND SUN. THIS WILL PLACE RECORDS IN DANGER FOR THAT PERIOD. WHILE JUST OUTSIDE THE FORECAST PERIOD IT IS WORTHY TO NOTE MAIN WAVE OF INTEREST WILL EJECT TOWARDS THE REGION. WITH HIGHLY VARIABLE TRACKS AND IMPLICATIONS ON THE AREA. THE GULF WILL BE WIDE OPEN WITH PWATS INCREASING TO OVER AN INCH...SUGGESTING AN INCREASED HEAVY RAIN THREAT WITH POSSIBLE THUNDERSTORMS TO WORRY ABOUT. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 113 AM EST MON DEC 7 2015 HAVE MADE SIGNIFICANT CHANGES TO THE ONGOING TAFS WITH THE 06Z ISSUANCE. SOME LIMITED CLEARING WITH VERY WEEK FLOW AT THE SURFACE AND LOW LAYERS HAS ALREADY ALLOWED PATCHY DENSE FOG TO DEVELOP OVER NORTHERN INDIANA BEFORE 06Z. THE FOG WAS MUCH MORE WIDESPREAD OVER LOWER MICHIGAN AND TO A LESSER EXTENT NORTHEAST ILLINOIS. MOST TEMP/DEW POINT SPREADS WERE 3 DEGREES OR LESS. GIVEN THE LATEST OBSERVATIONS AND TRENDS AND GIVEN THE LATEST HIGH RESOLUTION NCEP/WPC ESPECIALLY THE HRRR AND ARW...EXPECT THE FOG TO DEVELOP AND BECOME DENSE BEFORE 12Z. GIVEN THE WEAK FLOW...LIMITED INSOLATION THE FOG WILL BE VERY SLOW TO LIFT...WITH LINGERING STRATUS LIKELY THIS AFTERNOON. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...NONE. && $$ SYNOPSIS...AGD/SKIPPER SHORT TERM...AGD LONG TERM...FISHER AVIATION...SKIPPER VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSNORTHERNINDIANA WWW.TWITTER.COM/NWSIWX WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1155 PM EST SUN DEC 6 2015 .UPDATE... THE AVIATION SECTION HAS BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 211 PM EST SUN DEC 6 2015 A SERIES OF UPPER WAVES WILL BRING SMALL RAIN CHANCES TO CENTRAL INDIANA TONIGHT AND AGAIN WEDNESDAY. THEN...A DEEP UPPER TROUGH WILL SET UP OVER THE SOUTHWESTERN STATES. DISTURBANCES WILL EJECT NORTHEASTWARD AROUND THE BASE OF THE UPPER TROUGH AND THROUGH THE OHIO VALLEY. ALSO...A FRONTAL SYSTEM WILL APPROACH FROM THE WEST. THESE FEATURES WILL INTERACT WITH INCREASING AMOUNTS OF MOISTURE TO BRING PROLONGED RAIN CHANCES TO ALL OF CENTRAL INDIANA LATE NEXT WEEK AND NEXT WEEKEND. TEMPERATURES WILL START OFF SLIGHTLY ABOVE NORMAL WITH HIGHS IN THE MID TO UPPER 40S MONDAY. IT WILL BECOME EVEN MORE MILD LATER IN THE WEEK AND NEXT WEEKEND WITH AFTERNOON HIGHS IN THE LOWER 60S POSSIBLE BY SATURDAY. && .NEAR TERM /REST OF TONIGHT/... ISSUED AT 746 PM EST SUN DEC 6 2015 0030Z UPDATE...MAIN UPDATE EARLY THIS EVENING WAS TO INCREASE THE COVERAGE FOR LIGHT RAIN SHOWERS EARLY THIS EVENING BASED ON LATEST RADAR MOSAIC AND HRRR SOLUTION. THIS INCREASES THE POPS ACROSS SOME OF THE NORTHERN COUNTIES THROUGH THIS EVENING BEFORE THE BETTER LIFT AND MOISTURE MOVES SOUTH OF THE AREA. OTHER MINOR UPDATES WERE MADE TO ACCOUNT FOR THE LATEST IN TEMP/DEW POINT/WIND DIR/SPEED TRENDS. ZFPIND AND ASSOCIATED FORECAST PRODUCTS ALREADY. PREVIOUS DISCUSSION FOLLOWS. POPS WILL BE THE MAIN FOCUS TONIGHT AS AN UPPER LOW MOVES THROUGH THE ZONAL FLOW ALOFT AND TRACKS ACROSS THE INDIANA-MICHIGAN BORDER. WATER VAPOR LOOP WAS SHOWING THE UPPER LOW SPINNING ACROSS SOUTHEASTERN IOWA THIS AFTERNOON. THE MODELS ARE CLOSE AND BRING THE CENTER OF THE LOW TO NORTHEASTERN ILLINOIS BY 00Z TONIGHT AND TO WESTERN PARTS OF LAKE ERIE 12Z MONDAY. THE 12Z GFS...NAM AND GEM HAD ALL THE QPF NEAR AND SOUTH OF INTERSTATE 70...WHEREAS THE 00Z ECMWF HAD IT FURTHER NORTH ACROSS MUCH OR ALL OF CENTRAL INDIANA. THIS SEEMS TO GO ALONG THE FORMER MODELS BEING MORE COMPACT AND FURTHER SOUTH WITH THE HIGHER 1000-500 MILLIBAR RH BULLSEYE. WILL GO WITH THE MAJORITY AND KEEP CHANCE POPS SOUTH AND TRANSITION TO DRY ACROSS THE NORTHERNMOST TIER OR TWO. THE RAIN SHOWERS SHOULD BE ENDING FROM WEST TO EAST OVERNIGHT. WITH LOW STRATOCU DECK AROUND...PREFER THE WARMER 12Z GFS AND ENSEMBLE MOS. THE WET BULB ZERO TEMPERATURE SHOULD STAY JUST ABOVE FREEZING...SO DO NOT THINK WE WILL SEE A MIX OR CHANGEOVER OF THE RAIN SHOWERS TO SNOW SHOWERS. ALSO...SOME UPSTREAM LOW VISIBILITIES WERE SEEN IN THE SURFACE OBS ACROSS MISSOURI AND IOWA EARLY THIS AFTERNOON...SO WILL INCLUDE PATCHY FOG. && .SHORT TERM /MONDAY THROUGH WEDNESDAY/... ISSUED AT 211 PM EST SUN DEC 6 2015 MAIN CHALLENGE TO THE SHORT TERM WILL BE POPS AND CLOUD COVER AS MODELS HAVE A PAIR OF UPPER WAVES MOVING THROUGH THE VICINITY THROUGH WEDNESDAY. MODELS ARE HAVING DIFFERENCES WITH TIMING AND LOCATION WITH THESE FEATURES...WHICH MANY TIMES IS THE CASE IN DISTURBANCES MOVING THROUGH FAST ZONAL FLOW. THE WORK WEEK SHOULD START OFF WITH LINGERING STRATUS AND PATCHY FOG AS THE UPPER LOW MOVES TO WESTERN PARTS OF LAKE ERIE. MODEL SOUNDINGS SUGGEST STRONG INVERSION SHOULD KEEP AT LEAST SOME STRATOCU AROUND...AND LOCAL TRAPPING FLOW CHART SUGGESTS CLOUDS WILL HANG AROUND UP TO 24 HOURS LONGER THAN MOS SUGGESTS. SO...WILL SHOOT FOR MOSTLY CLOUDY TOMORROW. THIS SHOULD ALSO KEEP TEMPERATURES FROM HITTING 50 DEGREES DESPITE NICE LOW LEVEL THERMAL SETUP. THE 12Z GFS...CANADIAN AND NAM ARE THEN MUCH STRONGER AND FASTER AND FURTHER NORTH BRINGING AN UPPER WAVE OVER THE GREAT LAKES MONDAY NIGHT. THE 00Z ECMWF DOES NOT BRING THE WAVE ACROSS UNTIL TUESDAY AND BRINGS IT ACROSS THE OHIO VALLEY. EITHER WAY...MOISTURE IS LACKING SO...WILL NOT HAVE POPS MONDAY NIGHT OR TUESDAY. BY TUESDAY...THE LOWER LEVELS DRY ENOUGH THAT THERE SHOULD BE SOME SUNSHINE AROUND AFTER MORE MORNING STRATUS. LOW LEVEL THERMAL PROGS AND SOME SUNSHINE SUGGEST TEMPERATURES SHOULD BE A FEW DEGREES WARMER ON TUESDAY WITH MOS BLEND OF UPPER 40S TO LOWER 50S. THE LAST WAVE OF CONCERN SHOULD MOVE THROUGH THE OHIO VALLEY AND GREAT LAKES ON WEDNESDAY. THE 12Z NAM LOOKS TO BE THE ODD ONE OUT BEING MUCH FURTHER NORTH. WITH INCREASING SOUTHWESTERLY FLOW OVER THE AREA ON THE BACK SIDE OF AN EAST COAST HIGH...WILL SEE INCREASING MOISTURE TO GO ALONG WITH DECENT FORCING. THUS...AT LEAST CHANCE POPS FOR RAIN SHOWERS LOOK GOOD ACROSS ALL OF CENTRAL INDIANA ON WEDNESDAY. THE CLOUDS WILL KEEP TEMPERATURES FROM FALLING MUCH TUESDAY NIGHT WITH LOWS IN THE UPPER 30S TO LOWER 40S. THE CLOUDS AND SHOWERS SHOULD ALSO KEEP TEMPERATURES FROM RISING TOO MUCH WEDNESDAY WITH HIGHS IN THE UPPER 40S AND LOWER 50S. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... ISSUED AT 247 PM EST SUN DEC 6 2015 A QUASI-ZONAL FLOW ALOFT WILL OCCUR DURING THE FIRST HALF OF THE LONG TERM PERIOD AND THEN BECOME MORE AMPLIFIED OVER THE WEEKEND AS A STRONG UPPER TROUGH DIGS INTO THE CENTRAL U.S. BY LATE SATURDAY AND THEN MOVES TO THE WESTERN GREAT LAKES AND MISSISSIPPI VALLEY BY THE END OF DAY 7. A WEAK UPPER DISTURBANCE WILL BRING A CHANCE OF SHOWERS AROUND THURSDAY NIGHT AND THEN THE STRONG UPPER TROUGH WILL BRING A GOOD CHANCE OF SHOWERS OVER THE WEEKEND... ESPECIALLY SUNDAY. THERE MAY BE ENOUGH FORCING FOR ISOLATED THUNDER SATURDAY NIGHT INTO SUNDAY...BUT AT THE MOMENT I DECIDED TO LEAVE IT OUT. OVERALL SUPER BLEND SEEMED TO HANDLE POPS WELL. RAISED LOW TEMPERATURES SLIGHTLY SOME PERIODS DUE TO CLOUDS AND STRONG WARM ADVECTION. OTHERWISE...ONLY MINOR TWEAKS MADE DURING THE REST OF THE PERIOD. MODELS INDICATE TEMPERATURES WILL BE WELL ABOVE NORMAL DURING THE PERIOD...BUT POSSIBLY TURNING COOLER LATE SUNDAY WITH THE COLD FRONT. && .AVIATION /DISCUSSION FOR THE 07/06Z TAFS/... ISSUED AT 1155 PM EST SUN DEC 6 2015 VFR INITIALLY WILL GIVE WAY TO MVFR OR WORSE RESTRICTIONS LATER TONIGHT INTO MONDAY. VERY LOW CONFIDENCE FORECAST HOWEVER AS VARIOUS GUIDANCE PRODUCTS DIFFER SIGNIFICANTLY IN THEIR HANDLING OF EXPECTED CONDITIONS AND CONDITIONS UPSTREAM VARY SIGNIFICANTLY. WILL GENERALLY TREND THINGS DOWN TO LOW END MVFR BY THE EARLY PART OF THE OVERNIGHT AND KEEP THEM THERE THROUGH EARLY AFTERNOON MONDAY AS GUIDANCE TYPICALLY CLEARS SKIES FAR TOO EARLY IN THESE SITUATIONS. WINDS WILL BE 5KT OR LESS THROUGHOUT THE PERIOD. && .IND WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SYNOPSIS...MK NEAR TERM...SMF/MK SHORT TERM...MK LONG TERM...JH AVIATION...NIELD
AREA FORECAST DISCUSSION
NWS CARIBOU ME
923 PM EST TUE DEC 8 2015 .SYNOPSIS... HIGH PRESSURE WILL REMAIN OVER THE AREA TONIGHT THROUGH WEDNESDAY. THE HIGH WILL MOVE EAST WEDNESDAY NIGHT AS A WEAK TROUGH OF LOW PRESSURE APPROACHES FRO THE WEEST. THIS TROUGH IS EXPECTED TO CROSS THE REGION ON THURSDAY. && .NEAR TERM /THROUGH WEDNESDAY/... 924 PM UPDATE...CLOUDS CONTINUE TO BE BE THE BIGGEST FORECAST CHALLENGE. AN AREA OF CLOUDS WITH CEILINGS AROUND 4K FT AGL HAS BEEN RETREATING TO THE WEST WITH THE BACK EDGE OF THESE CLOUDS AROUND LEWISTOWN. ANOTHER AREA OF CLOUDS WITH SIMILAR CEILINGS APPEARS TO BE MOVING WEST ACROSS PARTS OF COASTAL DOWNEAST MAINE, BUT THEY ARE MORE DIFFICULT TO SEE ON SATELLITE DUE TO HIGHER CLOUDS ABOVE. A GOOD PORTION OF THE CWA IS CLEAR ATTM, WHICH HAS ALLOWED TEMPS TO DROP INTO THE UPPER TEENS TO MID 20S ACROSS MUCH OF THE CWA. THE 00Z KCAR SOUNDING SHOWED A SUBSIDENCE INVERSION AT 850H. EXPECT THAT WITH AN INCREASE IN LOW LEVEL MOISTURE OVERNIGHT THAT SOME AREAS OF LOWER CLOUD MAY DEVELOP ACROSS PORTIONS OF EASTERN MAINE ALONG WITH SOME PATCHY FOG IN THE RIVER VALLEYS. NO MAJOR CHANGES WITH THIS LATEST UPDATE, JUST SOME MINOR TWEAKS, MAINLY TO THE SKY GRIDS AND HOURLY TEMPERATURES BASED ON THE LATEST SATELLITE TRENDS AND OBSERVATIONS. PREVIOUS DISCUSSION... MAIN CHALLENGE THIS TERM AS HAS BEEN THE PAST FEW DAYS WILL BE THE CLOUDS AND TEMPS. SURFACE ANALYSIS SHOWED LOW PRES PASSING WELL SE OF THE AREA W/THE MID AND HIGH CLOUDS ASSOCIATED W/IT STARING TO PULL OUT OF THE DOWNEAST AND COASTAL AREA. FURTHER N AND W, SATELLITE IMAGERY SHOWED SOME CLOUDS AROUND AS WEAK UPPER IMPULSE PASSES BY TO THE N DESPITE HIGH PRES AT THE SURFACE. DOWNEAST AND THE COAST SHOULD REMAIN MOSTLY CLEAR OVERNIGHT W/HIGH PRES PULLING E. THOSE CLOUDS ACROSS THE NORTHERN SECTIONS WILL SLOWLY ERODE THIS EVENING, BUT MORE CLOUDS ARE FORECAST TO SET UP LATER TONIGHT AS A LIGHT ESE FLOW SETS UP ALLOWING FOR MOISTURE TO GET TRAPPED UNDER THE INVERSION. THE HRRR DOING WELL W/CURRENT SETUP AND SHOWED THE LLVL MOISTURE SETTING UP OVER EASTERN AND NORTHERN SECTIONS AFTER MIDNIGHT. TEMPS WILL VARY OVERNIGHT DEPENDENT ON THE CLOUDS. THIS WILL MAKE IT FOR A TOUGHT FORECAST. DECIDED TO GO W/UPPER TEENS TO LOWER 20S ACROSS THE NORTHERN 1/2 OF THE CWA W/THE COLDEST TEMPS IN THE LOW LYING AREAS AND NEAR RIVER VALLEYS. STAYED W/MID-UPPER 20S DOWNEAST AND THE COAST. THIS WILL NEED TO BE MONITORED AS SOME OF THE LOW LYING AREAS IN THIS REGION COULD GO COLDER DEPENDING ON LONGEVITY OF THE CLEARING. PATCHY FOG POSSIBLE ESPECIALLY ALONG THE RIVER VALLEYS. LOW CLOUDS WILL TAKE SOME TIME TO ERODE WEDNESDAY MORNING W/THE WEAK SE FLOW IN PLACE. DIRUNAL EFFECTS SHOULD AID IN ALLOWING FOR THE CLOUD DECK TO LIFT AND DISSIPATE SOME W/SUNSHINE. DAYTIME TEMPERATURES WILL BE A BIT ABOVE NORMAL FOR EARLY DECEMBER. && .SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/... HIGH PRESSURE WILL MOVE OFF THE COAST WEDNESDAY NIGHT WHILE AT THE SAME TIME LOW PRESSURE WILL PASS TO THE NORTHWEST OF NEW ENGLAND. THIS WILL RESULT IN A PERIOD OF SNOW AND RAIN AS WARM ADVECTION/OVERUNNING TAKE PLACE. SNOW AMOUNTS ARE EXPECTED TO BE MINIMAL AND CONFINED TO THE NORTH AND WEST AS THE PRECIPITATION IS EXPECTED TO QUICKLY CHANGE TO RAIN. ANOTHER PERIOD OF RAIN WITH SOME SNOW MIXED IS EXPECTED FRIDAY AS LOW PRESSURE DEVELOPS ACROSS NEW ENGLAND. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... LOW PRESSURE MOVING ACROSS QUEBEC WILL PUSH A WEAK FRONT ACROSS THE STATE FRI EVENING. A FEW SHWRS ARE EXPECTED IN ASSOCIATION, THOUGH BY THE 00Z SAT MUCH OF THE PRECIP MAY BE OVER FAR ERN & NRN MAINE, DEPARTING INTO NEW BRUNSWICK AS THE NIGHT PROGRESSES. AN UPR RIDGE AND WEAK SFC HIGH THEN BUILDS ACROSS THE AREA, ALLOWING FOR CLEARING SAT INTO AT LEAST SUN AM. BEYOND THEN, MODEL AGREEMENT BREAKS DOWN. WHILE BOTH THE GFS AND ECMWF WOULD AGREE ON SOME MORE ACTIVE WEATHER MONDAY INTO TUESDAY, THEY HAVE COMPLETELY DIFFERENT SOLUTIONS. THE GFS SHOWS ONE VERY POTENT SFC LOW DRIVEN BY A DEEP UPR TROF MOVING INTO ERN CANADA AND PUSHING A STRONG FRONT ACROSS THE STATE ON MON. THIS SOLUTION WOULD BRING ABUNDANT RAINFALL LATE SUN NIGHT THRU MON AFTERNOON, SWITCHING TO SNOW BEHIND THE FRONT AND LINGERING INTO TUE AFTERNOON. THE ECMWF IS COMPLETELY DIFFERENT, SHOWING ONE LOW DRIVEN BY A JET STREAK CROSSING THE CWA MON, AND A SECOND LOW DRIVEN BY AN UPR TROF OR CUT-OFF MOVING ACROSS ON TUE. HOWEVER, THE ECMWF HAS BEEN RATHER VARIABLE RUN-TO- RUN, WHILE THE GFS HAS BEEN A BIT MORE CONSISTENT. GIVEN THIS, AND THE FACT THAT THE CANADIAN APPEARS CLOSER TO THE GFS, ANY EDITS MADE SUN THRU TUE WERE SKEWED TOWARD THE GFS SOLUTION. && .AVIATION /02Z WEDNESDAY THROUGH SUNDAY/... NEAR TERM: VFR LATE THIS EVENING. A LLVL DECK, MVFR AND POSSIBLY EVEN IFR COULD DEVELOP AFTER MIDNIGHT AND LINGER INTO WED MORNING AS LIGHT ESE FLOW DEVELOPS. THIS DECK LOOKS LIKE IT WILL SET UP E OF THE BGR AND BHB TERMINALS. SHORT TERM: MVFR/VFR CONDITIONS ARE EXPECTED THURSDAY AND FRIDAY. && .MARINE... NEAR TERM: THE WIND AND SEAS ARE EXPECTED TO REMAIN BELOW SMALL CRAFT ADVISORY LEVELS THROUGH WEDNESDAY. SHORT TERM: HAVE USED A BLEND OF THE NAM12 AND GFS40 FOR WINDS. A SOUTHERLY FETCH WILL DEVELOP FROM THE GULF OF MAINE SOUTHWARD THURSDAY WITH WAVE HEIGHTS BUILDING TO AROUND 6 FEET/7 SECONDS. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...NONE. MARINE...NONE. && $$ NEAR TERM...CB/HEWITT SHORT TERM...MIGNONE LONG TERM...KREDENSOR AVIATION...CB/HEWITT/MIGNONE MARINE...CB/HEWITT/MIGNONE
AREA FORECAST DISCUSSION
NWS CARIBOU ME
618 PM EST TUE DEC 8 2015 .SYNOPSIS... HIGH PRESSURE WILL REMAIN OVER THE AREA TONIGHT THROUGH WEDNESDAY. THE HIGH WILL MOVE EAST WEDNESDAY NIGHT AS A WEAK TROUGH OF LOW PRESSURE APPROACHES FRO THE WEEST. THIS TROUGH IS EXPECTED TO CROSS THE REGION ON THURSDAY. && .NEAR TERM /THROUGH WEDNESDAY/... 618 PM UPDATE...AS HAS BEEN THE CASE THE PAST FEW DAYS THE MAIN CHALLENGES WILL BE CLOUD COVER AND TEMPERATURES. WHERE THE SKY IS CLEAR SOME SPOTS ARE ALREADY NEAR FORECAST LOWS AS OF 6 PM (PRESQUE ISLE 21F). HIGH CONFIDENCE THAT HIGH AND MID LEVEL CLOUDS BRUSHING BY THE DOWNEAST REGION THIS EVENING WITH A LOW WELL SE AND OFFSHORE WILL CLEAR OUT OVER THE COURSE OF THE EVENING. THERE ARE CURRENTLY SOME LOWER CLOUDS IN PARTS OF THE SAINT JOHN VALLEY AND WESTERN MAINE. AS LOW LEVEL MOISTURE GETS TRAPPED BELOW AN INVERSION IT IS LIKELY THAT ADDITIONAL LOW CLOUDS AND EVEN SOME PATCHY FOG MAY FORM AFTER MIDNIGHT, ESPECIALLY IN AREAS ALONG AND NEAR THE NEW BRUNSWICK BORDER. FORECAST CONFIDENCE ON THE TIMING AND EXTENT OF THESE CLOUDS IS FAIRLY LOW. THE MAIN UPDATES ARE TO THE SKY GRIDS FOR THE NEXT FEW HOURS BASED ON THE LATEST SATELLITE TRENDS. WILL ALSO MAKE SOME CHANGES TO THE HOURLY TEMPERATURES AND WILL NEED TO LOWER THEM A BIT IN AREAS SOUTH OF THE SAINT JOHN VALLEY INTO CENTRAL MAINE, BUT WILL NOT GO AS LOW AS THEY COULD POTENTIALLY GO DUE TO THE EXPECTATION THAT SOME LOW CLOUDS FORM OVERNIGHT AND CAUSE TEMPERATURES TO RISE. PREVIOUS DISCUSSION... MAIN CHALLENGE THIS TERM AS HAS BEEN THE PAST FEW DAYS WILL BE THE CLOUDS AND TEMPS. SURFACE ANALYSIS SHOWED LOW PRES PASSING WELL SE OF THE AREA W/THE MID AND HIGH CLOUDS ASSOCIATED W/IT STARING TO PULL OUT OF THE DOWNEAST AND COASTAL AREA. FURTHER N AND W, SATELLITE IMAGERY SHOWED SOME CLOUDS AROUND AS WEAK UPPER IMPULSE PASSES BY TO THE N DESPITE HIGH PRES AT THE SURFACE. DOWNEAST AND THE COAST SHOULD REMAIN MOSTLY CLEAR OVERNIGHT W/HIGH PRES PULLING E. THOSE CLOUDS ACROSS THE NORTHERN SECTIONS WILL SLOWLY ERODE THIS EVENING, BUT MORE CLOUDS ARE FORECAST TO SET UP LATER TONIGHT AS A LIGHT ESE FLOW SETS UP ALLOWING FOR MOISTURE TO GET TRAPPED UNDER THE INVERSION. THE HRRR DOING WELL W/CURRENT SETUP AND SHOWED THE LLVL MOISTURE SETTING UP OVER EASTERN AND NORTHERN SECTIONS AFTER MIDNIGHT. TEMPS WILL VARY OVERNIGHT DEPENDENT ON THE CLOUDS. THIS WILL MAKE IT FOR A TOUGHT FORECAST. DECIDED TO GO W/UPPER TEENS TO LOWER 20S ACROSS THE NORTHERN 1/2 OF THE CWA W/THE COLDEST TEMPS IN THE LOW LYING AREAS AND NEAR RIVER VALLEYS. STAYED W/MID-UPPER 20S DOWNEAST AND THE COAST. THIS WILL NEED TO BE MONITORED AS SOME OF THE LOW LYING AREAS IN THIS REGION COULD GO COLDER DEPENDING ON LONGEVITY OF THE CLEARING. PATCHY FOG POSSIBLE ESPECIALLY ALONG THE RIVER VALLEYS. LOW CLOUDS WILL TAKE SOME TIME TO ERODE WEDNESDAY MORNING W/THE WEAK SE FLOW IN PLACE. DIRUNAL EFFECTS SHOULD AID IN ALLOWING FOR THE CLOUD DECK TO LIFT AND DISSIPATE SOME W/SUNSHINE. DAYTIME TEMPERATURES WILL BE A BIT ABOVE NORMAL FOR EARLY DECEMBER. && .SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/... HIGH PRESSURE WILL MOVE OFF THE COAST WEDNESDAY NIGHT WHILE AT THE SAME TIME LOW PRESSURE WILL PASS TO THE NORTHWEST OF NEW ENGLAND. THIS WILL RESULT IN A PERIOD OF SNOW AND RAIN AS WARM ADVECTION/OVERUNNING TAKE PLACE. SNOW AMOUNTS ARE EXPECTED TO BE MINIMAL AND CONFINED TO THE NORTH AND WEST AS THE PRECIPITATION IS EXPECTED TO QUICKLY CHANGE TO RAIN. ANOTHER PERIOD OF RAIN WITH SOME SNOW MIXED IS EXPECTED FRIDAY AS LOW PRESSURE DEVELOPS ACROSS NEW ENGLAND. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... LOW PRESSURE MOVING ACROSS QUEBEC WILL PUSH A WEAK FRONT ACROSS THE STATE FRI EVENING. A FEW SHWRS ARE EXPECTED IN ASSOCIATION, THOUGH BY THE 00Z SAT MUCH OF THE PRECIP MAY BE OVER FAR ERN & NRN MAINE, DEPARTING INTO NEW BRUNSWICK AS THE NIGHT PROGRESSES. AN UPR RIDGE AND WEAK SFC HIGH THEN BUILDS ACROSS THE AREA, ALLOWING FOR CLEARING SAT INTO AT LEAST SUN AM. BEYOND THEN, MODEL AGREEMENT BREAKS DOWN. WHILE BOTH THE GFS AND ECMWF WOULD AGREE ON SOME MORE ACTIVE WEATHER MONDAY INTO TUESDAY, THEY HAVE COMPLETELY DIFFERENT SOLUTIONS. THE GFS SHOWS ONE VERY POTENT SFC LOW DRIVEN BY A DEEP UPR TROF MOVING INTO ERN CANADA AND PUSHING A STRONG FRONT ACROSS THE STATE ON MON. THIS SOLUTION WOULD BRING ABUNDANT RAINFALL LATE SUN NIGHT THRU MON AFTERNOON, SWITCHING TO SNOW BEHIND THE FRONT AND LINGERING INTO TUE AFTERNOON. THE ECMWF IS COMPLETELY DIFFERENT, SHOWING ONE LOW DRIVEN BY A JET STREAK CROSSING THE CWA MON, AND A SECOND LOW DRIVEN BY AN UPR TROF OR CUT-OFF MOVING ACROSS ON TUE. HOWEVER, THE ECMWF HAS BEEN RATHER VARIABLE RUN-TO- RUN, WHILE THE GFS HAS BEEN A BIT MORE CONSISTENT. GIVEN THIS, AND THE FACT THAT THE CANADIAN APPEARS CLOSER TO THE GFS, ANY EDITS MADE SUN THRU TUE WERE SKEWED TOWARD THE GFS SOLUTION. && .AVIATION /00Z WEDNESDAY THROUGH SUNDAY/... NEAR TERM: VFR EARLY TONIGHT WITH MVFR AT KFVE AT TIMES. A LLVL DECK, MVFR AND POSSIBLY EVEN IFR COULD DEVELOP AFTER MIDNIGHT AND LINGER INTO WED MORNING AS LIGHT ESE FLOW DEVELOPS. THIS DECK LOOKS LIKE IT WILL SET UP E OF THE BGR AND BHB TERMINALS. SHORT TERM: MVFR/VFR CONDITIONS ARE EXPECTED THURSDAY AND FRIDAY. && .MARINE... NEAR TERM: THE WIND AND SEAS ARE EXPECTED TO REMAIN BELOW SMALL CRAFT ADVISORY LEVELS THROUGH WEDNESDAY. SHORT TERM: HAVE USED A BLEND OF THE NAM12 AND GFS40 FOR WINDS. A SOUTHERLY FETCH WILL DEVELOP FROM THE GULF OF MAINE SOUTHWARD THURSDAY WITH WAVE HEIGHTS BUILDING TO AROUND 6 FEET/7 SECONDS. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...NONE. MARINE...NONE. && $$ NEAR TERM...CB/HEWITT SHORT TERM...MIGNONE LONG TERM...KREDENSOR AVIATION...CB/HEWITT/MIGNONE MARINE...CB/HEWITT/MIGNONE
AREA FORECAST DISCUSSION
NWS CARIBOU ME
314 PM EST MON DEC 7 2015 .SYNOPSIS... A WEAK COLD FRONT WILL CROSS MOVE OFF THE MAINE COAST THIS EVENING. HIGH PRESSURE WILL BUILD TOWARD THE AREA TONIGHT AND REMAIN UNTIL WEDNESDAY. A TROUGH OF LOW PRESSURE WILL APPROACH LATER THURSDAY INTO FRIDAY. && .NEAR TERM /THROUGH TUESDAY/... 19Z SURFACE ANALYSIS HAD COLD FRONT MOVING ACROSS NORTH-CENTRAL AREAS. MRMS AND CANADIAN RADAR FROM QUEBEC SHOWED SOME LIGHT RAIN/SNOW SHOWERS MOVING THROUGH FAR NORTHERN MAINE. KFVE REPORTED A MIX RAIN/SNOW W/THE FROPA. TEMPS HAVE MAXED OUT WILL DROP AS COLDER AIR MOVES INTO THE REGION TONIGHT. HRRR AND RAP GUIDANCE SHOWED A BAND OF PRECIP DROPPING SE LATE THIS AFTERNOON INTO EARLY EVENING W/THE FRONT. NOT MUCH MEASURABLE PRECIP IF ANY AT ALL W/THE BAND. THE BAND OF PRECIP IS FORECAST TO WEAKEN AS IT DROPS SE THIS EVENING. WX ELEMENT WILL BE LIGHT RAIN/SNOW SHOWERS. TEMPS OVERNIGHT WILL DEPENDENT ON CLOUD COVER. NNW WINDS WILL DROP OFF QUICKLY THIS EVENING AS HIGH PRES QUICKLY BUILDS E BEHIND THEFRONT. AS WELL STATED BY THE MIDNIGHT CREW, THE BIGGEST FORECAST CHALLENGES WILL BE THE EXTENT OF THE RADIATION INVERSION AS SHOWN BY THE MODEL SOUNDINGS AND WHETHER CLOUDS WILL BE TRAPPED UNDER THE SUBSIDENCE INVERSION. THIS WILL LEAD TO A CHALLENGE W/THE TEMP FORECAST. CLEARING SKIES COULD READINGS TO DIP INTO THE LOWER TEENS FOR NORTHERN AND WESTERN ZONES. A WIDESPREAD CLOUD COVER WOULD KEEP TEMPS UP INTO THE MID TO UPPER 20S. ATTM, DECIDED TO USE A CONSENSUS OF THE CONSRAW GUIDANCE AND SHOWED AT LEAST PARTLY CLOUDY CONDITIONS FOR LATER TONIGHT. THIS SHOULD ALLOW FOR SOME RADIATIONAL COOLING AND LEANED W/UPPER TEENS AND LOWERS 20S NORTH AND WEST AND MID/UPPER 20S ELSEWHERE. TUESDAY SHOULD FEATURE A LEAST PARTLY SUNNY DAY BUT COOLER W/HIGH PRES BUILDING IN FROM THE W. THINKING HERE IS THAT AFTERNOON TEMPERATURES WILL BE AT LEAST 5 TO 10 DEGREES COOLER THAN TODAY. && .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/... EXPECT WEAK HIGH PRESSURE TO BE LOCATED OVER THE AREA TUESDAY NIGHT. THIS SYSTEM WILL THEN GRADUALLY MOVE TO THE EAST WEDNESDAY. CLOUDS WILL START TO INCREASE WEDNESDAY NIGHT AS WARM ADVECTION TAKES PLACE IN THE RETURN FLOW BEHIND THE HIGH. SHOWERS ARE THEN POSSIBLE ON THURSDAY AS A WARM FRONT APPROACHES. FOR TEMPERATURES WILL USE THE BIAS CONSENSUS BLEND FOR HIGH AND THE CONSENSUS RAW FOR LOWS BASED ON LASTEST VERIFICATION. && .LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/... LOW PRESSURE IS EXPECTED TO PASS WELL TO THE NORTHWEST OF NEW ENGLAND DURING THE DAY FRIDAY. HIGH PRESSURE CENTERED TO THE SOUTH OF NEW ENGLAND WILL MOVE ACROSS THE REGION SATURDAY. ANOTHER LOW PRESSURE SYSTEM WILL MOVE FROM THE WESTERN GREAT LAKES INTO WESTERN QUEBEC PROVINCE EARLY SUNDAY AS STRONG HIGH PRESSURE MOVES EASTWARD INTO THE ATLANTIC. LOW PRESSURE MAY DEVELOP OFF THE NEW ENGLAND COAST MONDAY. && .AVIATION /20Z MONDAY THROUGH SATURDAY/... NEAR TERM: EXPECTING MAINLY VFR THROUGH TUESDAY. THERE COULD BE A BRIEF PERIOD OF MVFR THIS EVENING ACROSS THE NORTHERN TERMINALS W/THE COLD FROPA. SHORT TERM: VFR CONDITIONS ARE EXPECTED WEDNESDAY AND THURSDAY. MVFR CONDITIONS EXPECTED FRIDAY. VFR CONDITIONS ARE THEN EXPECTED SATURDAY. && .MARINE... NEAR TERM: NO HEADLINES THIS TERM. STAYED CLOSE TO THE DAYCREW`S ASSESSMENT OF BRINGING WINDS UP TO 10-15 KTS SUSTAINED W/GUSTS TO 20 KTS. THIS WILL MAINLY BE ACROSS THE OUTER ZONES. WAVE HEIGHTS WILL BE 3-4 INTO EARLY TUESDAY. SHORT TERM: HAVE BLENDED THE NAM12 AND GFS40 FOR SUSTAINED WINDS. FOR WAVES: OFF-SHORE WIND WAVE WILL DOMINATE ON WEDNESDAY. A SOUTHERLY FETCH FROM THE GULF OF MAINE SOUTHWARD IS EXPECTED TO DOMINATE FROM THURSDAY THROUGH THE WEEKEND. WAVES MAY APPROACH SCA TURSDAY NIGHT. WILL USE THE NEAR SHORE WAVE MODEL TO POPULATE WAVE GRIDS. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...NONE. MARINE...NONE. && $$ NEAR TERM...HEWITT SHORT TERM...MIGNONE LONG TERM...MIGNONE AVIATION...HEWITT/MIGNONE MARINE...HEWITT/MIGNONE
AREA FORECAST DISCUSSION
NWS GRAY ME
1238 PM EST MON DEC 7 2015 .SYNOPSIS... A WEAK COLD FRONT WILL SAG SOUTH FROM CANADA AND MOVE OFFSHORE BY THIS AFTERNOON. HIGH PRESSURE BUILDS IN FROM THE WEST TONIGHT. LOW PRESSURE DEEPENS OFF THE VIRGINIA COAST TUESDAY MORNING AND STAYS SOUTH OF THE GULF OF MAINE AND MOVES NORTHEAST. A RIDGE OF HIGH PRESSURE CROSSES THE AREA WEDNESDAY. A WEAK DISTURBANCE WILL CROSS THE REGION WEDNESDAY NIGHT INTO THURSDAY. A WARM FRONT CROSSES THE AREA FRIDAY WITH MILD WEATHER EXPECTED FOR THE UPCOMING WEEKEND. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 1230 PM UPDATE...UPDATED TEMPERATURES TO MATCH UP WITH CURRENT OBS AND TRENDS. FOG IS JUST ABOUT GONE IN THE CT RIVER VALLEY...SO IT LOOKS LIKE THE CURRENT FORECAST OF FOG TO 18Z IS ACCURATE. THE FORECAST CHALLENGE TONIGHT WILL BE WHETHER OR NOT TO BRING FOG BACK INTO THE VALLEY AREAS...FORECAST RAP SOUNDINGS ARE INDICATING THE PRESENCE OF FOG DURING THE OVERNIGHT. FOR NOW IT IS IN THE FORECAST...BUT THIS IS SOMETHING TO LOOK INTO A BIT MORE FOR THE AFTERNOON FORECAST PACKAGE. 1015 AM UPDATE...THE EDGE OF THE FOG IN THE CT RIVER VALLEY CONTINUES TO SLOWLY RECEDE BIT BY BIT...BUT HAD TO EXTEND KEEPING FOG/FZFG IN THE FORECAST INTO EARLY AFTERNOON. 9 AM UPDATE...THE FOG IS NOT NEARLY AS EXPANSIVE ACROSS THE CT RIVER VALLEY THIS MORNING AS IT WAS YESTERDAY AND AT THE EDGES IT IS STARTING TO BURN OFF. UPDATED THE WEATHER TO INCLUDE FZFG/FG IN THE CT RIVER VALLEY THROUGH 15Z. THE ONLY OTHER CHANGES NEEDED WERE TO ALIGN TEMPERATURES WITH CURRENT OBSERVATIONS AND TRENDS. UPDATE... HAVE REMOVED FREEZING FOG AND MOST OF THE FOG FROM THE FORECAST AFTER 12Z AS ONLY LEBANON AND KEENE ARE REPORTING ANYTHING. THIS HAS BEEN THE CASE ALL NIGHT AND FEEL THE LOW LEVEL MOISTURE IS JUST NOT THERE. OTHERWISE NO MAJOR CHANGES TO THE FORECAST. I DID ADJUST SKY COVER AS CLEAR SKIES HAVE DEVELOPED OVER NORTHERN SECTIONS. THIS WILL NOT LAST HOWEVER AS TODAY`S COLD FRONT IS STILL TO OUR NORTH. PREVIOUS DISCUSSION... FREEZING FOG AND BLACK ICE LOOKING MUCH LESS PREVALENT TONIGHT AS OPPOSED TO LAST NIGHT. THIS IS DUE TO LESS LOW LEVEL MOISTURE AND THIN CLOUD COVER. HAVE CONTINUED MENTIONING IT IN PRODUCTS FOR A COUPLE MORE HOURS AS THERE ARE MAY BE ISOLATED ICY PATCHES. AFTER A CHILLY NIGHT TEMPERATURES REBOUND QUICKLY TODAY IN A DRY AIRMASS. READINGS WILL WARM INTO THE UPPER 30S/LOWER 40S NORTH TO UPPER 40S/LOWER 50S SOUTH. WINDS GRADUALLY TURN NORTHERLY TODAY AS A WEAK BACKDOOR FRONT SAGS SOUTH OUT OF CANADA. NO PRECIPITATION IS EXPECTED WITH THIS FEATURE AND IT WILL MOVE OFFSHORE IN THE AFTERNOON HOURS. IT WILL HOWEVER INDUCE SOME CLOUD COVER IN THE MOUNTAINS AND FOOTHILLS...AND DOWNSLOPING WILL KEEP THE COASTAL PLAIN MOSTLY SUNNY. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/... TODAY WILL BE CHILLY WITH READINGS IN THE LOWER 20S NORTH TO UPPER 20S/LOWER 30S SOUTH. A FEW TEENS MAY BE POSSIBLE ACROSS THE NORTH DEPENDING ON CLOUD COVER. PW VALUES ARE FORECAST TO DROP BELOW TWO-TENTHS OF AN INCH OVERNIGHT AND THIS IS AN INDICATOR OF GOOD RADIATIONAL COOLING...AND A LACK OF CLOUDS. INDEED NORTHERLY FLOW BECOMES LIGHT AND VARIABLE AS HIGH PRESSURE MOVES IN BEHIND THE NOW WASHED OUT OFFSHORE FRONT...ANOTHER SIGNAL THAT CLOUDS MAY BE BREAKING UP IN THE HIGHER TERRAIN. WHERE CLOUDS ARE ABSENT AND WINDS DIMINISH WE MAY SEE SOME FOG DEVELOP. TUESDAY`S WEATHER WILL ONLY BE SLIGHTLY IMPACTED BY A LARGE LOW PRESSURE SYSTEM THAT IS PROGGED TO MOVE TOWARDS THE GULF OF MAINE AND THEN TURN ENE WHEN IT BECOMES LEVEL WITH CAPE COD. WE WILL SEE INCREASING CLOUD COVER BUT NO PRECIPITATION. IN THIS WAY TEMPERATURES WILL BE LOWER THAN TODAY AND ONLY WARM INTO THE LOWER 40S OVER SOUTHERN SECTIONS. && .LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... THE MODELS ARE IN GOOD AGREEMENT ON THE LONG WAVE PATTERN THROUGH EARLY NEXT WEEKEND. NEARLY ZONAL FLOW WILL GRADUALLY AMPLIFY BY LATE IN THE WEEK IN RESPONSE TO STRONG SHORTWAVE MOVING ONSHORE OVER THE WESTERN CONUS. THIS GIVES RISE TO WESTERN TROUGH AND EASTERN RIDGE FOR THE UPCOMING WEEKEND. INCREASING UNCERTAINTY THEREAFTER...AS MODELS SOLUTIONS DIVERGE. HOWEVER...THROUGH D+6 THERE WILL BE A CONTINUED ABSENCE OF ARCTIC AIR AS PACIFIC FLOW DOMINATES WITH WELL ABOVE NORMAL TEMPERATURES TO CONTINUE FOR THE FORECAST AREA. IN THE DAILIES...SURFACE HIGH PRESSURE WILL SLIDE OFFSHORE WEDNESDAY WITH DEVELOPING MILDER RETURN FLOW. SHORTWAVE IMPULSE AND ASSOCIATED WEAK SURFACE REFLECTION CROSSES THE REGION WITH A FEW SHOWERS WEDNESDAY NIGHT AND EARLY THURSDAY. WE`LL BE IN BETWEEN SYSTEMS LATE THURSDAY INTO FRIDAY BEFORE NEXT SHORTWAVE IMPULSE APPROACHES. AN ASSOCIATED WARM FRONT LIFTS NORTH ACROSS THE AREA WITH A FEW CLOUDS AND SCATTERED SHOWERS. IN ITS WAKE...BROAD SOUTHWEST FLOW AND RISING HEIGHTS WITH WELL ABOVE NORMAL TEMPERATURES FOR NEXT WEEKEND. CONSIDERABLE UNCERTAINTY THEREAFTER REGARDING HOW FAST SHORTWAVE ENERGY MANAGES TO BREAK DOWN THE EASTERN RIDGE...AND DRIVE A SURFACE COLD FRONT ACROSS THE REGION. && .AVIATION /18Z MONDAY THROUGH SATURDAY/... SHORT TERM... 1230 PM UPDATE...FOG HAS ALMOST COMPLETELY BURNED OFF IN THE CT RIVER VALLEY WITH LEB HOLDING ON TO VLIFR CEILINGS. LEB SHOULD COME BACK TO VFR IN THE NEXT HOUR TO HOUR IN A HALF. FOG MAY BE ABLE TO DEVELOP AGAIN TONIGHT BUT RIGHT NOW THERE IS A LITTLE UNCERTAINTY AS HIGH PRESSURE HAS WEAKENED AND THE LOW LEVEL INVERSION DOES NOT QUITE AS STRONG AS IT HAS BEEN THE PAST COUPLE DAYS. PREVIOUS DISCUSSION...VFR CONDITIONS TO PREVAIL EXCEPT IN PATCHY DENSE FZFG...MAINLY AT KLEB...KHIE...AS WELL AS FG AT KRKD THROUGH 13Z TODAY AND AGAIN LATE TONIGHT. LONG TERM... THU...SCT MVFR PSBL IN -SHRA/-SHSN. && .MARINE... SHORT TERM...WINDS INCREASE AND WE MAY SEE A FEW GUSTS NEAR 20 KTS LATE TONIGHT INTO TUESDAY...HOWEVER EXPECT GUSTS TO REMAIN SUB- SCA.SEAS SHOULD REMAIN 2-4 FT. LONG TERM... THU...SMALL CRAFT POSSIBLE OUTSIDE THE BAYS. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...NONE. NH...NONE. MARINE...NONE. && $$ SYNOPSIS... NEAR TERM...KISTNER SHORT TERM... LONG TERM... AVIATION... MARINE...
AREA FORECAST DISCUSSION
NWS CARIBOU ME
1126 AM EST MON DEC 7 2015 .SYNOPSIS... A WEAK COLD FRONT WILL CROSS THE REGION THIS AFTERNOON. HIGH PRESSURE BUILDS OVER THE AREA TONIGHT AND REMAIN UNTIL WEDNESDAY. A TROUGH OF LOW PRESSURE WILL APPROACH THURSDAY. && .NEAR TERM /THROUGH TONIGHT/... 1120 AM UPDATE...UPDATED THE AFTERNOON TEMPS BY AT LEAST 3 DEGREES. SOME AREAS ALREADY NEAR PREVIOUS FORECAST HIGHS FOR THE AFTERNOON. MORE SUN HAS ALLOWED THE TEMPS TO CLIMB. HRRR DOING FINE W/CLOUDS AND POSSIBLE RAIN/SNOW SHOWER N AND W THIS AFTERNOON. PREVIOUS DISCUSSION... THE COLD FRONT WILL ENTER THE SAINT JOHN VALLEY THIS AFTERNOON AND CONTINUE WEAKENING AS IT PROGRESSES SOUTHWARD THROUGH THE AFTERNOON. THE ACTUAL FRONTAL PASSAGE MAY PRODUCE A QUICK PERIOD OF DRIZZLE OR SNOW FLURRIES AS IT CROSSES. THIS IS DUE TO A SHALLOW UNSTABLE LAYER UP TO H850. ANY PRECIPITATION WILL BE VERY LIGHT AND CONFINED TO AROOSTOOK COUNTY. THAT SAID...MOST GUIDANCE IS NOT SHOWING ANY POPS. MAY ADD A NARROW BAND OF FLURRIES IN NORTHERN AROOSTOOK THIS AFTERNOON FOR THE NEXT UPDATE. HIGH PRESSURE WILL BUILD RAPIDLY BEHIND THE FRONT FOR TONIGHT WITH LIGHT WINDS. THE BIGGEST FORECAST CHALLENGES FOR TONIGHT WILL BE THE EXTENT OF THE RADIATION INVERSION AND WHETHER CLOUDS WILL BE TRAPPED UNDER THE SUBSIDENCE INVERSION. WITHOUT ANY CLOUDS...TEMPERATURES COULD DIP INTO THE UPPER SINGLE DIGITS AND LOWER TEENS FOR NORTHERN ZONES. HOWEVER...MORE WIDESPREAD STRATOCUMULUS UNDER YET ANOTHER SUBSIDENCE INVERSION WILL HOLD LOWS INTO THE MID TO UPPER 20S. WHILE DEW POINTS WILL DROP OFF INTO THE UPPER TEENS TONIGHT...THIS IS FAR FROM A DRY ARCTIC AIR MASS. HAVE PLAYED THE MIDDLE GROUND FOR THIS FORECAST...FOLLOWING MOS GUIDANCE. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... RIDGE AXIS WL BE OVR CWA AT THE START OF THE SHORT TERM. SFC LOW GOES WELL OFFSHORE WITH MINIMAL IMPACT ON CWA AS 1030MB HIGH KEEPS IT WELL TO THE SOUTH. HIPRES SHIFTS EAST WED WITH RETURN FLOW COMMENCING, HELPING TEMPS MODERATE THRU THE END OF THE SHORT TERM. EXPECT H5 RIDGE ACRS THE STATE FOR WED WITH MILD ABV NORMAL TEMPS FOR HIGHS ONCE AGAIN. TROF ROTATES ACRS AREA WED NGT WITH ISOLD SNOW SHOWERS POSSIBLE IN WARM ADVECTION. && .LONG TERM /THURSDAY THROUGH SUNDAY/... AS NOTED BY PREVIOUS SHIFT HV KEPT POPS CONFINED TO SLT CHC/CHC POPS THRU LONG TERM OWING TO MODEL DISCREPANCIES. 00Z GFS HAS SFC LOW IN THE GULF OF MAIN FOR THUR WHEREAS GEM AND EC DO NOT INDICATE THIS. PRETTY NEGLIGIBLE IN TERMS OF WX-MAKERS FOR AREA THRU END OF THE PD WITH JUST MINOR S/WVS ROTATING THRU. BY LATE IN THE PD DISCREPANCIES BCM EVEN BIGGER WITH SYSTEM DVLPNG ACRS THE CENTER OF THE NATION. && .AVIATION /18Z MONDAY THROUGH SATURDAY/... NEAR TERM: CONDITIONS WILL BE VFR TO START THIS MORNING EXCEPT FOG ALONG THE COAST TO INCLUDE BHB. THE FOG WILL ERODE TOWARDS MID MORNING OR EARLIER. MEANWHILE...MVFR CIGS WILL MOVE INTO FVE AND PROGRESS SOUTH TO HUL BY LATE MORNING. THESE CIGS MAY MAKE IT TO BGR AND BHB BY LATE AFTERNOON...BUT ONLY BRIEFLY. ALL SITES WILL LIKELY BE VFR TONIGHT WITH THE POSSIBLE EXCEPTION OF FVE WITH CONTINUING MVFR CIGS. SHORT TERM: VFR EXPECTED THROUGH WED UNDER HIGH PRESSURE. SOUTHERLY FLOW MAY BRING IN MVFR CIGS AS A TROUGH SWINGS THROUGH AND BRINGS SNOW SHOWERS TO THE REGION FOR ALL BUT BHB. MVFR AND POSSIBLE IFR RESTRICTIONS EXPECTED ON FRI MAINLY FOR NORTHERN TERMINALS. && .MARINE... NEAR TERM: SSW WINDS WILL PICK UP THIS AFTERNOON AHEAD OF COLD FRONT WITH A FEW GUSTS APPROACHING 20 KTS AND SEAS AROUND 4 FT. WINDS WILL SHIFT TO THE NORTH BEHIND THE FRONT. THE COLD AIR MOVING OVER THE WATERS WILL CONTINUE TO PRODUCE A FEW GUSTS TO 20 KTS TONIGHT. SHORT TERM: SEAS AND WINDS WILL REMAIN BELOW SCA THRESHOLDS THROUGH WED NIGHT. WAVES WILL APPROACH SCA THUR MORNING THROUGH THE END OF THE PERIOD. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...NONE. MARINE...NONE. && $$ NEAR TERM...HEWITT
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
1023 PM EST TUE DEC 8 2015 .UPDATE... THE INHERITED PUBLIC FORECAST REMAINS IN GOOD SHAPE FOR THE OVERNIGHT HOURS. IN LIGHT OF CURRENT TEMPERATURES...A MINOR GRID EDIT WAS TO RAISE LOWS A DEGREE OR TWO. THE FEELING FROM OBSERVATIONAL TRENDS IS ONE OF LOW CONFIDENCE FOR FOG AND LOW CEILING DEVELOPMENT OVERNIGHT. SOUTHEASTERN MICHIGAN WILL REMAIN IN PRIME POSITION FOR INCREASING SOUTHERLY GRADIENT FLOW IN ADVANCE OF THE APPROACHING MIDLEVEL TROUGH. NAM 950 MB WINDS ARE SOLIDLY IN THE 25 TO 35 KNOT RANGE IN ADVANCE OF A WEAK COLD FRONT...WHICH SHOULD HAVE INFLUENCE AT THE SURFACE. NOT LOOKING AT A TOTAL DECOUPLING SCENARIO...THUS COMPROMISING THE POTENTIAL FOR SIGNIFICANT FOG OVERNIGHT. && .AVIATION...ISSUED 707 PM EST TUE DEC 8 2015 IN MONITOR MODE EARLY THIS EVENING WITH PERSISTENT MVFR/VFR VISIBILITIES IN BR/HZ ACROSS ALL OF SOUTHEASTERN MICHIGAN. LOOKING AT A DIFFERENT SETUP WITH EXTENSIVE MID-HI CLOUD SHIELD IN ADVANCE OF THE NEXT MIDLEVEL TROUGH. OPACITY OF CLOUDS APPEARS HIGH ENOUGH THAT EARLY POST SUNSET TEMPERATURES ARE RUNNING SOME 4-6 DEGREES WARMER THAN YESTERDAY. THE BOTTOM LINE IS WILL CONTINUE THE INHERITED MENTION OF IFR CIGS/VSBYS LATER TONIGHT GIVEN THE ABUNDANCE OF SURFACE OBSERVATIONS REPORTING 5-7SM IN BR/HZ. HRRR DOES SUPPORT A POTENTIAL FOR SURFACE FOG DEVELOPING ALONG A DIFFUSE WARM FRONTAL FEATURE THAT WILL LIFT SOUTH TO NORTH BETWEEN 00-06Z. THE RUC IS MUCH LESS BULLISH BUT DOES SHOW SOME AGREEMENT TO THE TIMING FROM SOUTH TO NORTH. AN INCREASE IN MOISTURE INTO A DEVELOPING FRONTAL INVERSION AHEAD THE APPROACHING MIDLEVEL TROUGH SUPPORTS AN EXTENSIVE STRATUS DECK IN PLACE FOR WEDNESDAY. FOR DTW...WEDGE OF DRY AIR CORRESPONDING TO SUBTLE SHORTWAVE RIDGING AHEAD OF APPROACHING MIDLEVEL LOW PRESSURE SYSTEM HAS LED TO A LOSS OF MVFR CEILINGS EARLY THIS EVENING. CURRENT TEMPERATURES POST SUNSET IN THE LOWER TO MIDDLE 40S HIGHLIGHTS THE PATTERN EVOLUTION SEEN FROM THE PAST FEW NIGHTS. WILL MAINTAIN THE IFR CIGS/VSBYS LATER TONIGHT. //DTW THRESHOLD PROBABILITIES... * LOW IN VSBY/CIGS AOB 1/2SM AND/OR 200 FT TONIGHT THROUGH 14Z WEDNESDAY MORNING. * HIGH IN CIGS BELOW 5000 FT LATER TONIGHT AND WEDNESDAY. LOW CONFIDENCE IN TIMING. && .PREV DISCUSSION...ISSUED 324 PM EST TUE DEC 8 2015 DISCUSSION... MILD PERIOD FOR THIS TIME OF YEAR WITH HIGHS POSSIBLY REACHING NEAR 60 THIS WEEKEND. AS FOR THE REST OF THIS AFTERNOON AND EVENING PARTIAL CLEARING IS MAKING ITS WAY NORTHWARD INTO SOUTHEAST MICHIGAN AS THE LOWER LEVEL STRATUS MIXES OUT WITH DAYTIME HEATING. MID TO UPPER LEVEL CLOUDS AHEAD OF NEXT SYSTEM ARE ALSO MOVING IN SO SKIES SHOULD RANGE FROM PARTLY TO MOSTLY CLOUDY. AS SUNSETS ANY CLEAR SKY SHOULD QUICKLY FILL IN WITH LOW STRATUS AGAIN. THERE WILL BE FOG DEVELOPMENT AGAIN TONIGHT THOUGH NOT AS DENSE AS PAST SEVERAL NIGHTS AS PRODUCTIVE RADIATIONAL COOLING WILL BE HAMPERED BY MID AND UPPER LEVEL CLOUDS STREAMING IN AHEAD OF NEXT SYSTEM. THIS SYSTEM IS AN UPPER WAVE/SFC TROUGH ACROSS THE CENTRAL U.S. THAT WILL TRACK THROUGH THE GREAT LAKES WEDNESDAY. SOUTHERLY FLOW AHEAD OF THIS SYSTEM WILL DRAW IN DECENT MOISTURE UP THROUGH 850MB. THIS WILL MAINTAIN PLENTY OF LOW LEVEL MOISTURE AND A BROKEN TO OVERCAST SKY TONIGHT. LOW LEVEL CONVERGENCE WEAKENS AS THE WAVE AND SFC TROUGH BEGIN TO FLATTEN AS IT CROSSES THE STATE. THERE WILL STILL BE ENOUGH LIFT TO PRODUCE SCATTERED LIGHT RAIN SHOWERS. MID LEVEL HEIGHT RISES AND DRY SLOTTING WILL SPREAD ACROSS THE AREA WEDNESDAY NIGHT AHEAD OF NEXT PACIFIC WAVE TRAVERSING THE NORTHERN BORDER. THIS WILL CONTINUE TO DRAW LOW LEVEL MOISTURE INTO THE AREA THROUGH THURSDAY NIGHT. AN OVERALL PERSISTENCE OF LOW STRATUS WILL CONTINUE MOSTLY CLOUDY SKIES WEDNESDAY NIGHT AND THRU MOST OF THURSDAY NIGHT. FORCING FROM THIS SYSTEM WILL DECREASE SOUTHWARD INTO SOUTHEAST MICHIGAN AND SO WILL CHANCES FOR A LIGHT SHOWER THURSDAY AFTERNOON AND THURSDAY NIGHT. TEMPERATURES WILL REMAIN MILD WITH LOWS MODERATING FROM THE 30S TO THE 40S AND HIGHS FROM THE 40S TO THE 50S THROUGH FRIDAY MORNING. A VERY BRIEF DRY SPELL ON FRIDAY AND FRIDAY NIGHT WILL BE QUICKLY FOLLOWED BY AN APPROACHING LOW PRESSURE SYSTEM FOR THE WEEKEND. THIS LOW WILL BRING A CHANCE OF RAIN TO SOUTHEAST MICHIGAN BEGINNING ON SATURDAY AS THE WARM FRONT PUSHES ACROSS THE GREAT LAKES.THE COLD FRONT THEN PUSHES THROUGH ON SUNDAY AFTERNOON/EVENING.THERE IS STILL QUITE A BIT OF MODEL DISAGREEMENT ON THE TRACK AND TIMING OF THIS SYSTEM. HAVE KEPT LIKELY POPS /60 PERCENT/ IN THE FORECAST FOR THIS ISSUANCE FOR MUCH OF SUNDAY AND SUNDAY NIGHT. THIS WILL LIKELY HAVE TO BE FINE TUNED A LITTLE WHEN THE TRACK BECOMES MORE CERTAIN. PRECIPITATION TAPERS OFF SLOWLY ON MONDAY AS THE LOW TRACKS NORTHEASTWARD. THERE IS ALSO A POTENTIAL FOR SOME RAIN/SNOW MIX HEADING INTO MONDAY NIGHT AND TUESDAY MORNING. AGAIN...THIS IS HIGHLY TRACK DEPENDENT...WITH A MORE SOUTHERLY TRACK RESULTING IN THE BEST CHANCE TO SEE MIXED PRECIP. HAVE ONLY INCLUDED A MENTION IN THE FORECAST FOR NOW. MARINE... A TROUGH OF LOW PRESSURE TRACKING ACROSS THE GREAT LAKES WILL BRING AN INCREASE IN SOUTHERLY WINDS LATE TONIGHT AND WEDNESDAY. THE STRONGEST WINDS WILL BE OVER LAKE HURON...BUT SUSTAINED SPEEDS ARE ONLY EXPECTED TO TOP OUT AT 15 TO 20 KNOTS...AND GUSTS SHOULD REMAIN NEAR OR BELOW 20 KNOTS. RAIN SHOWERS WILL ALSO BE POSSIBLE WEDNESDAY. AFTER A PERIOD OF LIGHTER SOUTHWEST WINDS WEDNESDAY NIGHT...ANOTHER AREA OF LOW PRESSURE LIFTING ACROSS LAKE SUPERIOR WILL INCREASE THE PRESSURE GRADIENT ONCE AGAIN ON THURSDAY. THE STRONGER WINDS WILL LAST LONGER WITH THIS SECOND LOW...WITH SPEEDS INCREASING FIRST FROM THE SOUTH THURSDAY...AND THEN SOUTHWEST THURSDAY NIGHT INTO FRIDAY. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LAKE HURON...NONE. LAKE ST CLAIR...NONE. MICHIGAN WATERS OF LAKE ERIE...NONE. && $$ UPDATE.......CB AVIATION.....CB DISCUSSION....DRC/RK MARINE.......HLO YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
707 PM EST TUE DEC 8 2015 .AVIATION... IN MONITOR MODE EARLY THIS EVENING WITH PERSISTENT MVFR/VFR VISIBILITIES IN BR/HZ ACROSS ALL OF SOUTHEASTERN MICHIGAN. LOOKING AT A DIFFERENT SETUP WITH EXTENSIVE MID-HI CLOUD SHIELD IN ADVANCE OF THE NEXT MIDLEVEL TROUGH. OPACITY OF CLOUDS APPEARS HIGH ENOUGH THAT EARLY POST SUNSET TEMPERATURES ARE RUNNING SOME 4-6 DEGREES WARMER THAN YESTERDAY. THE BOTTOM LINE IS WILL CONTINUE THE INHERITED MENTION OF IFR CIGS/VSBYS LATER TONIGHT GIVEN THE ABUNDANCE OF SURFACE OBSERVATIONS REPORTING 5-7SM IN BR/HZ. HRRR DOES SUPPORT A POTENTIAL FOR SURFACE FOG DEVELOPING ALONG A DIFFUSE WARM FRONTAL FEATURE THAT WILL LIFT SOUTH TO NORTH BETWEEN 00-06Z. THE RUC IS MUCH LESS BULLISH BUT DOES SHOW SOME AGREEMENT TO THE TIMING FROM SOUTH TO NORTH. AN INCREASE IN MOISTURE INTO A DEVELOPING FRONTAL INVERSION AHEAD THE APPROACHING MIDLEVEL TROUGH SUPPORTS AN EXTENSIVE STRATUS DECK IN PLACE FOR WEDNESDAY. FOR DTW...WEDGE OF DRY AIR CORRESPONDING TO SUBTLE SHORTWAVE RIDGING AHEAD OF APPROACHING MIDLEVEL LOW PRESSURE SYSTEM HAS LED TO A LOSS OF MVFR CEILINGS EARLY THIS EVENING. CURRENT TEMPERATURES POST SUNSET IN THE LOWER TO MIDDLE 40S HIGHLIGHTS THE PATTERN EVOLUTION SEEN FROM THE PAST FEW NIGHTS. WILL MAINTAIN THE IFR CIGS/VSBYS LATER TONIGHT. //DTW THRESHOLD PROBABILITIES... * LOW IN VSBY/CIGS AOB 1/2SM AND/OR 200 FT TONIGHT THROUGH 14Z WEDNESDAY MORNING. * HIGH IN CIGS BELOW 5000 FT LATER TONIGHT AND WEDNESDAY. LOW CONFIDENCE IN TIMING. && .PREV DISCUSSION...ISSUED 324 PM EST TUE DEC 8 2015 DISCUSSION... MILD PERIOD FOR THIS TIME OF YEAR WITH HIGHS POSSIBLY REACHING NEAR 60 THIS WEEKEND. AS FOR THE REST OF THIS AFTERNOON AND EVENING PARTIAL CLEARING IS MAKING ITS WAY NORTHWARD INTO SOUTHEAST MICHIGAN AS THE LOWER LEVEL STRATUS MIXES OUT WITH DAYTIME HEATING. MID TO UPPER LEVEL CLOUDS AHEAD OF NEXT SYSTEM ARE ALSO MOVING IN SO SKIES SHOULD RANGE FROM PARTLY TO MOSTLY CLOUDY. AS SUNSETS ANY CLEAR SKY SHOULD QUICKLY FILL IN WITH LOW STRATUS AGAIN. THERE WILL BE FOG DEVELOPMENT AGAIN TONIGHT THOUGH NOT AS DENSE AS PAST SEVERAL NIGHTS AS PRODUCTIVE RADIATIONAL COOLING WILL BE HAMPERED BY MID AND UPPER LEVEL CLOUDS STREAMING IN AHEAD OF NEXT SYSTEM. THIS SYSTEM IS AN UPPER WAVE/SFC TROUGH ACROSS THE CENTRAL U.S. THAT WILL TRACK THROUGH THE GREAT LAKES WEDNESDAY. SOUTHERLY FLOW AHEAD OF THIS SYSTEM WILL DRAW IN DECENT MOISTURE UP THROUGH 850MB. THIS WILL MAINTAIN PLENTY OF LOW LEVEL MOISTURE AND A BROKEN TO OVERCAST SKY TONIGHT. LOW LEVEL CONVERGENCE WEAKENS AS THE WAVE AND SFC TROUGH BEGIN TO FLATTEN AS IT CROSSES THE STATE. THERE WILL STILL BE ENOUGH LIFT TO PRODUCE SCATTERED LIGHT RAIN SHOWERS. MID LEVEL HEIGHT RISES AND DRY SLOTTING WILL SPREAD ACROSS THE AREA WEDNESDAY NIGHT AHEAD OF NEXT PACIFIC WAVE TRAVERSING THE NORTHERN BORDER. THIS WILL CONTINUE TO DRAW LOW LEVEL MOISTURE INTO THE AREA THROUGH THURSDAY NIGHT. AN OVERALL PERSISTENCE OF LOW STRATUS WILL CONTINUE MOSTLY CLOUDY SKIES WEDNESDAY NIGHT AND THRU MOST OF THURSDAY NIGHT. FORCING FROM THIS SYSTEM WILL DECREASE SOUTHWARD INTO SOUTHEAST MICHIGAN AND SO WILL CHANCES FOR A LIGHT SHOWER THURSDAY AFTERNOON AND THURSDAY NIGHT. TEMPERATURES WILL REMAIN MILD WITH LOWS MODERATING FROM THE 30S TO THE 40S AND HIGHS FROM THE 40S TO THE 50S THROUGH FRIDAY MORNING. A VERY BRIEF DRY SPELL ON FRIDAY AND FRIDAY NIGHT WILL BE QUICKLY FOLLOWED BY AN APPROACHING LOW PRESSURE SYSTEM FOR THE WEEKEND. THIS LOW WILL BRING A CHANCE OF RAIN TO SOUTHEAST MICHIGAN BEGINNING ON SATURDAY AS THE WARM FRONT PUSHES ACROSS THE GREAT LAKES.THE COLD FRONT THEN PUSHES THROUGH ON SUNDAY AFTERNOON/EVENING.THERE IS STILL QUITE A BIT OF MODEL DISAGREEMENT ON THE TRACK AND TIMING OF THIS SYSTEM. HAVE KEPT LIKELY POPS /60 PERCENT/ IN THE FORECAST FOR THIS ISSUANCE FOR MUCH OF SUNDAY AND SUNDAY NIGHT. THIS WILL LIKELY HAVE TO BE FINE TUNED A LITTLE WHEN THE TRACK BECOMES MORE CERTAIN. PRECIPITATION TAPERS OFF SLOWLY ON MONDAY AS THE LOW TRACKS NORTHEASTWARD. THERE IS ALSO A POTENTIAL FOR SOME RAIN/SNOW MIX HEADING INTO MONDAY NIGHT AND TUESDAY MORNING. AGAIN...THIS IS HIGHLY TRACK DEPENDENT...WITH A MORE SOUTHERLY TRACK RESULTING IN THE BEST CHANCE TO SEE MIXED PRECIP. HAVE ONLY INCLUDED A MENTION IN THE FORECAST FOR NOW. MARINE... A TROUGH OF LOW PRESSURE TRACKING ACROSS THE GREAT LAKES WILL BRING AN INCREASE IN SOUTHERLY WINDS LATE TONIGHT AND WEDNESDAY. THE STRONGEST WINDS WILL BE OVER LAKE HURON...BUT SUSTAINED SPEEDS ARE ONLY EXPECTED TO TOP OUT AT 15 TO 20 KNOTS...AND GUSTS SHOULD REMAIN NEAR OR BELOW 20 KNOTS. RAIN SHOWERS WILL ALSO BE POSSIBLE WEDNESDAY. AFTER A PERIOD OF LIGHTER SOUTHWEST WINDS WEDNESDAY NIGHT...ANOTHER AREA OF LOW PRESSURE LIFTING ACROSS LAKE SUPERIOR WILL INCREASE THE PRESSURE GRADIENT ONCE AGAIN ON THURSDAY. THE STRONGER WINDS WILL LAST LONGER WITH THIS SECOND LOW...WITH SPEEDS INCREASING FIRST FROM THE SOUTH THURSDAY...AND THEN SOUTHWEST THURSDAY NIGHT INTO FRIDAY. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LAKE HURON...NONE. LAKE ST CLAIR...NONE. MICHIGAN WATERS OF LAKE ERIE...NONE. && $$ AVIATION.....CB DISCUSSION....DRC/RK MARINE.......HLO YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
411 PM EST MON DEC 7 2015 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 410 PM EST MON DEC 7 2015 WV IMAGERY AND RAP ANALYSIS INDICATED AN UPSTREAM SHORTWAVE TROUGH OVER THE UPPER MS VALLEY. AT THE SFC...A TROUGH EXTENDED INTO WRN MN FROM LOW PRES OVER SRN MANITOBA. ALTHOUGH RADARS SHOWED SOME WEAK RETURNS OVER NRN INTO CNTRL WI...NO SFC REPORTS OF PCPN WERE NOTED. VIS SATELLITE INDICATED MID/HIGH CLOUDS MOVING ACROSS UPPER MICHIGAN OVER THE LOW STRATUS AND FOG OVER MOST OF THE CNTRL AND ERN CWA. CLOSER TO LAKE SUPERIOR IN THE WEST HALF...DOWNSLOPE SRLY FLOW HAS HELPED SCOUR OUT THE LOW CLOUDS. TONIGHT...EXPECT THAT WITH CONTINUED SRLY LOW LEVEL FLOW OF MOISTURE BENEATH THE STRONG 875 MB INVERSION (12Z KGRB SOUNDING) THAT THE FOG/STRATUS WILL PERSIST TONIGHT AND THICKEN WITH NOCTURNAL COOLING. ALTHOUGH 850-500 MB QVECTOR CONV AND 280K ISENTROPIC LIFT AHEAD OF THE SHRTWV IS EXPECTED...THE 850-700 MB DRY LAYER WILL BE STRONG ENOUGH TO PREVENT ICE NUCLEI FROM REACHING THE LOWER MOIST LAYER. SO...WILL MENTION DZ/FZDZ SPREADING WEST TO EAST MAINLY AFTER 03Z...ESPECIALLY WHERE UPSLOPE FLOW PREVAILS. ADDITIONAL MOISTENING WITH THE FLOW OFF OF LAKE MICHIGAN WILL ALSO FAVOR GREATER DZ POTENTIAL OVER THE ERN CWA. CLOSE TO LAKE SUPERIOR...EXPECT DRIER AND SLIGHTLY WARMER CONDITIONS WITH LESS/NO PCPN/FOG. TUESDAY...ANY LINGERING DZ/FZDZ IN THE MORNING OVER THE CNTRL AND ERN CWA IS EXPECTED TO DEPART BY 15Z. HOWEVER...LOW CLOUDS SHOULD LINGER WITH WEAK SSW LOW LEVEL FLOW AND LACK OF ANY DRY ADVECTION. THIS SHOULD HELP LIMIT MAX TEMPS TO NEAR THE LOWER END OF GUIDANCE. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 322 PM EST MON DEC 7 2015 ABOVE NORMAL TEMPERATURES WILL CONTINUE OVER THE UPPER GREAT LAKES REGION THROUGH THE WORK WEEK AS SEVERAL WEAK WAVES MOVE FROM WEST TO EAST ACROSS THE AREA. THIS WILL LEAD TO OCCASIONAL OPPORTUNITIES FOR RAIN...WITH THE BETTER CHANCES FOR PRECIPITATION COMING THIS WEEKEND INTO NEXT WEEK...AS AN UPPER TROUGH AMPLIFIES OVER THE WESTERN CONUS AND EJECTS A COUPLE WAVES TOWARDS THE REGION THROUGH THE MIDDLE OF NEXT WEEK. THERE WILL BE TWO WEST-EAST WAVES AFFECTING THE REGION THIS WEEK...THE FIRST OCCURRING ON TUESDAY NIGHT INTO WEDNESDAY AND A SECOND...STRONGER WAVE THURSDAY AFTERNOON INTO FRIDAY. IN BOTH CASES...EXPECT PRIMARILY RAIN TO OCCUR...BUT THERE COULD BE ENOUGH COLD AIR WRAPPING IN ON THE BACK SIDE OF THE SECOND WAVE THURSDAY NIGHT INTO FRIDAY TO LOWER WETBULB ZERO HEIGHTS TO LEAD TO SOME SNOW OVER THE WESTERN U.P.. THAT COULD ALSO OCCUR WITH THE FIRST WAVE...BUT THINK THE PRECIPITATION WILL LARGELY BE DONE BY THE TIME THAT HAPPENS. QPF AMOUNTS TUESDAY NIGHT INTO WEDNESDAY MORNING WILL RANGE FROM 0.05 TO 0.15IN...WITH THE GREATEST AMOUNTS OVER THE EASTERN HALF OF THE CWA. THE SECOND EVENT WILL LARGELY DEPEND ON THE TRACK OF THE LOW ACROSS THE AREA...BUT THINK THE HIGHEST AMOUNTS WILL OCCUR OVER THE NORTHWEST HALF (OVER A QUARTER INCH OF QPF POSSIBLE OVER WESTERN LAKE SUPERIOR). FOR THE WEEKEND INTO NEXT WEEK...MODELS CONTINUE TO SHOW THE POTENTIAL FOR A STRONGER SYSTEM TO MOVE THROUGH THE GREAT LAKES REGION LATE THIS WEEKEND INTO NEXT WEEK. THIS IS DUE TO THE UPPER TROUGH AMPLIFYING OVER THE WESTERN CONUS AND AN AMPLIFYING UPPER RIDGE OVER THE EASTERN CONUS AND WESTERN ATLANTIC. THAT PUTS THE REGION IN THE RIGHT LOCATION FOR A POSSIBLE STRONGER STORM MOVING THROUGH SOMETIME IN THE 5-10 DAY TIME FRAME. WITH THE FAIRLY AMPLIFIED TROUGH/RIDGE...SOME COLD AIR DOES TRY TO FILTER INTO THE CWA FOR THE SECOND HALF OF THE WEEKEND...SO THAT DOES CREATE SOME POTENTIAL FOR SNOW IF A SYSTEM OCCURS. THE 12Z RUNS LOOK TO TRACK THE HEAVIEST QPF TO THE SOUTHEAST OF THE AREA...BUT IT IS STILL 6 PLUS DAYS OUT AND WILL HAVE PLENTY OF TIME TO ADJUST AND LOOK AT ANY POTENTIAL SYSTEMS OVER THE COMING DAYS. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 125 PM EST MON DEC 7 2015 PERSISTENT LOW LEVEL SRLY UPSLOPE FLOW ALONG WITH ABUNDANT LOW LEVEL MOISTURE ACROSS THE REGION WILL SUSTAIN LIFR TO OCNLY VLIFR CONDITIONS THROUGH MOST OF THE TAF PERIOD. SOME DRIZZLE OR FREEZING DRIZZLE MAY ALSO BE POSSIBLE LATE TONIGHT INTO TUE MORNING. AT IWD/CMX...A MORE DOWNSLOPE WIND DIRECTION WILL KEEP MAINLY VFR CONDITIONS UNTIL LATER THIS EVENING WHEN NOCTURNAL COOLING WILL HELP SUPPORT STRATUS FORMATION WITH IFR CIGS. CONDITIONS WILL ONLY GRADUALLY IMPROVE TUE MORNING. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 410 PM EST MON DEC 7 2015 THE PRESSURE GRADIENT WILL INCREASE TONIGHT AS A LOW PRESSURE SYSTEM MOVES INTO NW ONTARIO. THIS WILL SUPPORT A PERIOD OF 25-30 KNOT WIND GUSTS TONIGHT INTO TUE MORNING. ANOTHER PERIOD OF SOUTHERLY 25 KNOT WINDS IS EXPECTED THU INTO THU NIGHT OVER ERN LAKE SUPERIOR AHEAD OF A LOW PRESSURE SYSTEM MOVING INTO THE UPPER MS VALLEY. OTHERWISE...WINDS WILL REMAIN BELOW 25 KNOTS. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...SRF AVIATION...JLB MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
322 PM EST MON DEC 7 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 353 AM EST MON DEC 7 2015 00Z RAOBS/LATEST WV IMAGERY AND RAP ANALYSIS SHOW A ZONAL SPLIT FLOW OF PACIFIC AIR OVER SRN CANADA AND THE CONUS. SHRTWV RDG AXIS IS MOVING INTO THE WRN GREAT LKS EARLY THIS MRNG...WITH WEAK SFC HI PRES RDG STRETCHING FM NW ONTARIO ACRS WRN UPR MI TO STRONGER HI PRES CENTERED OVER THE SRN PLAINS. ALTHOUGH THE AIRMASS OVHD IS DRY...WITH 00Z PWAT AS LO AS ABOUT 0.20 INCH AT MPX...LINGERING LLVL MSTR SHOWN ON LOCAL 00Z RAOBS TRAPPED UNDER LO SUBSIDENCE INVRN IS CAUSING QUITE A BIT OF LO CLD/FOG OVER MUCH OF THE CWA IN THE PRESENCE OF NOCTURNAL COOLING. THE FOG/STRATUS IS MOST EXTENSIVE OVER THE INTERIOR W HALF OF THE CWA...WITH MORE HIER BASED SC LINGERING OVER THE E...WHERE THE 00Z GRB/APX RAOBS SHOW MORE MSTR NEAR HIER INVRN BASE. AREAS NEAR LK SUP W OF MUNISING...EXCEPT FOR THE KEWEENAW...AND OVER THE SCENTRAL E OF IRON MTN ARE MOCLR... PROBABLY DUE TO LIGHT DOWNSLOPE W TO SW WINDS IN THESE AREAS. THE LO CLD AND FOG STRETCH W THRU MUCH OF MN. MORE HI CLD IN COMMA TAIL OF NRN BRANCH SHRTWV/SFC LO TRACKING INTO MANITBOA IS STREAMING E INTO MN AS WELL...BUT VERY DRY AIRMASS SHOWN ON THE ABERDEEN SDAKOTA AND BISMARCK RAOBS IS PREVENTING ANY PCPN OR EVEN LOWER CLDS. MAIN FCST CONCERNS IN THE SHORT TERM ARE FOCUSED ON FOG/LO CLD TRENDS. TODAY...AS SFC HI PRES RDG SHIFTS TO THE E AND LO PRES MOVES INTO NW ONTARIO...EXPECT A STEADY S WIND TO DVLP OVER UPR MI. NAM H95 RH... WHICH HAS A GOOD HANDLE ON THE AREA OF LO CLDS RIGHT NOW...HINTS THE AREA OF LO CLDS WL EXPAND TO ALL BUT THE NW CWA...WHERE THE S WIND DOWNSLOPES. WHILE DAYTIME HEATING WL LIKELY LIMIT FOG COVERAGE...LO SUN ANGLE WL PROBABLY NOT BE SUFFICIENT TO MIX OUT THE LO CLD. SO TENDED TOWARD MORE CLD COVER EXCEPT IN THOSE DOWNSLOPE AREAS NEAR LK SUP FM MUNISING TO BARAGA/THE KEWEENAW...ONTONAGON AND IRONWOOD. LOWERED FCST MAX TEMPS A COUPLE DEGREES WHERE THE LO CLD IS EXPECTED TO BE MOST EXTENSIVE. EXPECT THE WARMEST TEMPS INTO THE 40S IN THE DOWNSLOPE AREAS NEAR LK SUP. TNGT...AXIS OF DEEP LYR QVECTOR CNVGC IN COMMA TAIL OF SHRTWV MOVING TO THE ENE TOWARD HUDSON BAY IS FCST TO SHIFT W-E ACRS THE CWA. ALTHOUGH THIS FORCING WL NOT BE SUFFICIENT TO SATURATE THE VERY DRY MID LVLS...LIFTING OF THE SUBSIDENCE INVRN WL ALLOW FOR A GREATER DEPTH OF LLVL MSTR. MANY OF THE HIER RES MODELS GENERATE SOME LGT PCPN...ESPECIALLY IN AREAS DOWNWIND OF LK MI IN THE EXPECTED LLVL SSW FLOW. WL RETAIN SOME LO CHC POPS FOR DRIZZLE AND ADD SOME FOG IN THE FCST FOR THIS AREA. THE SOMEWHAT HIER INVRN BASE WL ALSO ALLOW FOR MORE LO CLDS TO EXPAND EVEN INTO THE DOWNSLOPE AREAS NEAR LK SUP. TEMPS WL RUN WELL ABOVE NORMAL...MAINLY IN THE 30S...WARMEST DOWNWIND OF LK MI. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 322 PM EST MON DEC 7 2015 ABOVE NORMAL TEMPERATURES WILL CONTINUE OVER THE UPPER GREAT LAKES REGION THROUGH THE WORK WEEK AS SEVERAL WEAK WAVES MOVE FROM WEST TO EAST ACROSS THE AREA. THIS WILL LEAD TO OCCASIONAL OPPORTUNITIES FOR RAIN...WITH THE BETTER CHANCES FOR PRECIPITATION COMING THIS WEEKEND INTO NEXT WEEK...AS AN UPPER TROUGH AMPLIFIES OVER THE WESTERN CONUS AND EJECTS A COUPLE WAVES TOWARDS THE REGION THROUGH THE MIDDLE OF NEXT WEEK. THERE WILL BE TWO WEST-EAST WAVES AFFECTING THE REGION THIS WEEK...THE FIRST OCCURRING ON TUESDAY NIGHT INTO WEDNESDAY AND A SECOND...STRONGER WAVE THURSDAY AFTERNOON INTO FRIDAY. IN BOTH CASES...EXPECT PRIMARILY RAIN TO OCCUR...BUT THERE COULD BE ENOUGH COLD AIR WRAPPING IN ON THE BACK SIDE OF THE SECOND WAVE THURSDAY NIGHT INTO FRIDAY TO LOWER WETBULB ZERO HEIGHTS TO LEAD TO SOME SNOW OVER THE WESTERN U.P.. THAT COULD ALSO OCCUR WITH THE FIRST WAVE...BUT THINK THE PRECIPITATION WILL LARGELY BE DONE BY THE TIME THAT HAPPENS. QPF AMOUNTS TUESDAY NIGHT INTO WEDNESDAY MORNING WILL RANGE FROM 0.05 TO 0.15IN...WITH THE GREATEST AMOUNTS OVER THE EASTERN HALF OF THE CWA. THE SECOND EVENT WILL LARGELY DEPEND ON THE TRACK OF THE LOW ACROSS THE AREA...BUT THINK THE HIGHEST AMOUNTS WILL OCCUR OVER THE NORTHWEST HALF (OVER A QUARTER INCH OF QPF POSSIBLE OVER WESTERN LAKE SUPERIOR). FOR THE WEEKEND INTO NEXT WEEK...MODELS CONTINUE TO SHOW THE POTENTIAL FOR A STRONGER SYSTEM TO MOVE THROUGH THE GREAT LAKES REGION LATE THIS WEEKEND INTO NEXT WEEK. THIS IS DUE TO THE UPPER TROUGH AMPLIFYING OVER THE WESTERN CONUS AND AN AMPLIFYING UPPER RIDGE OVER THE EASTERN CONUS AND WESTERN ATLANTIC. THAT PUTS THE REGION IN THE RIGHT LOCATION FOR A POSSIBLE STRONGER STORM MOVING THROUGH SOMETIME IN THE 5-10 DAY TIME FRAME. WITH THE FAIRLY AMPLIFIED TROUGH/RIDGE...SOME COLD AIR DOES TRY TO FILTER INTO THE CWA FOR THE SECOND HALF OF THE WEEKEND...SO THAT DOES CREATE SOME POTENTIAL FOR SNOW IF A SYSTEM OCCURS. THE 12Z RUNS LOOK TO TRACK THE HEAVIEST QPF TO THE SOUTHEAST OF THE AREA...BUT IT IS STILL 6 PLUS DAYS OUT AND WILL HAVE PLENTY OF TIME TO ADJUST AND LOOK AT ANY POTENTIAL SYSTEMS OVER THE COMING DAYS. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 125 PM EST MON DEC 7 2015 PERSISTENT LOW LEVEL SRLY UPSLOPE FLOW ALONG WITH ABUNDANT LOW LEVEL MOISTURE ACROSS THE REGION WILL SUSTAIN LIFR TO OCNLY VLIFR CONDITIONS THROUGH MOST OF THE TAF PERIOD. SOME DRIZZLE OR FREEZING DRIZZLE MAY ALSO BE POSSIBLE LATE TONIGHT INTO TUE MORNING. AT IWD/CMX...A MORE DOWNSLOPE WIND DIRECTION WILL KEEP MAINLY VFR CONDITIONS UNTIL LATER THIS EVENING WHEN NOCTURNAL COOLING WILL HELP SUPPORT STRATUS FORMATION WITH IFR CIGS. CONDITIONS WILL ONLY GRADUALLY IMPROVE TUE MORNING. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 310 AM EST MON DEC 7 2015 THE PRESSURE GRADIENT WILL INCREASE THIS AFTERNOON INTO TONIGHT AS A LOW PRESSURE SYSTEM MOVES INTO NW ONTARIO. THIS WILL SUPPORT A PERIOD OF 25-30 KNOT WIND GUSTS TONIGHT INTO TUE MORNING. ANOTHER PERIOD OF SOUTHERLY 25 KNOT WINDS IS EXPECTED THU INTO THU NIGHT AHEAD OF A LOW PRESSURE SYSTEM MOVING INTO THE UPPER MS VALLEY. OTHERWISE...WINDS WILL REMAIN BELOW 25 KNOTS. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...KC LONG TERM...SRF AVIATION...JLB MARINE...TITUS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
126 PM EST MON DEC 7 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 353 AM EST MON DEC 7 2015 00Z RAOBS/LATEST WV IMAGERY AND RAP ANALYSIS SHOW A ZONAL SPLIT FLOW OF PACIFIC AIR OVER SRN CANADA AND THE CONUS. SHRTWV RDG AXIS IS MOVING INTO THE WRN GREAT LKS EARLY THIS MRNG...WITH WEAK SFC HI PRES RDG STRETCHING FM NW ONTARIO ACRS WRN UPR MI TO STRONGER HI PRES CENTERED OVER THE SRN PLAINS. ALTHOUGH THE AIRMASS OVHD IS DRY...WITH 00Z PWAT AS LO AS ABOUT 0.20 INCH AT MPX...LINGERING LLVL MSTR SHOWN ON LOCAL 00Z RAOBS TRAPPED UNDER LO SUBSIDENCE INVRN IS CAUSING QUITE A BIT OF LO CLD/FOG OVER MUCH OF THE CWA IN THE PRESENCE OF NOCTURNAL COOLING. THE FOG/STRATUS IS MOST EXTENSIVE OVER THE INTERIOR W HALF OF THE CWA...WITH MORE HIER BASED SC LINGERING OVER THE E...WHERE THE 00Z GRB/APX RAOBS SHOW MORE MSTR NEAR HIER INVRN BASE. AREAS NEAR LK SUP W OF MUNISING...EXCEPT FOR THE KEWEENAW...AND OVER THE SCENTRAL E OF IRON MTN ARE MOCLR... PROBABLY DUE TO LIGHT DOWNSLOPE W TO SW WINDS IN THESE AREAS. THE LO CLD AND FOG STRETCH W THRU MUCH OF MN. MORE HI CLD IN COMMA TAIL OF NRN BRANCH SHRTWV/SFC LO TRACKING INTO MANITBOA IS STREAMING E INTO MN AS WELL...BUT VERY DRY AIRMASS SHOWN ON THE ABERDEEN SDAKOTA AND BISMARCK RAOBS IS PREVENTING ANY PCPN OR EVEN LOWER CLDS. MAIN FCST CONCERNS IN THE SHORT TERM ARE FOCUSED ON FOG/LO CLD TRENDS. TODAY...AS SFC HI PRES RDG SHIFTS TO THE E AND LO PRES MOVES INTO NW ONTARIO...EXPECT A STEADY S WIND TO DVLP OVER UPR MI. NAM H95 RH... WHICH HAS A GOOD HANDLE ON THE AREA OF LO CLDS RIGHT NOW...HINTS THE AREA OF LO CLDS WL EXPAND TO ALL BUT THE NW CWA...WHERE THE S WIND DOWNSLOPES. WHILE DAYTIME HEATING WL LIKELY LIMIT FOG COVERAGE...LO SUN ANGLE WL PROBABLY NOT BE SUFFICIENT TO MIX OUT THE LO CLD. SO TENDED TOWARD MORE CLD COVER EXCEPT IN THOSE DOWNSLOPE AREAS NEAR LK SUP FM MUNISING TO BARAGA/THE KEWEENAW...ONTONAGON AND IRONWOOD. LOWERED FCST MAX TEMPS A COUPLE DEGREES WHERE THE LO CLD IS EXPECTED TO BE MOST EXTENSIVE. EXPECT THE WARMEST TEMPS INTO THE 40S IN THE DOWNSLOPE AREAS NEAR LK SUP. TNGT...AXIS OF DEEP LYR QVECTOR CNVGC IN COMMA TAIL OF SHRTWV MOVING TO THE ENE TOWARD HUDSON BAY IS FCST TO SHIFT W-E ACRS THE CWA. ALTHOUGH THIS FORCING WL NOT BE SUFFICIENT TO SATURATE THE VERY DRY MID LVLS...LIFTING OF THE SUBSIDENCE INVRN WL ALLOW FOR A GREATER DEPTH OF LLVL MSTR. MANY OF THE HIER RES MODELS GENERATE SOME LGT PCPN...ESPECIALLY IN AREAS DOWNWIND OF LK MI IN THE EXPECTED LLVL SSW FLOW. WL RETAIN SOME LO CHC POPS FOR DRIZZLE AND ADD SOME FOG IN THE FCST FOR THIS AREA. THE SOMEWHAT HIER INVRN BASE WL ALSO ALLOW FOR MORE LO CLDS TO EXPAND EVEN INTO THE DOWNSLOPE AREAS NEAR LK SUP. TEMPS WL RUN WELL ABOVE NORMAL...MAINLY IN THE 30S...WARMEST DOWNWIND OF LK MI. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 310 AM EST MON DEC 7 2015 LONG TERM WILL SEE SEVERAL SHORTWAVES MAKING FOR A BUSIER PATTERN...BUT AT THIS TIME PRECIP AMOUNTS LOOK TO BE MOSTLY INSIGNIFICANT. MAY SEE SOME MORE SIGNIFICANT PRECIP NEXT WEEKEND...BUT PREDICTABILITY IS QUITE LOW. MAY SEE SOME LIGHT PRECIP OVER THE E ON TUE...MAINLY TUE MORNING...AS A SHORTWAVE PASSES THROUGH. MODELS SHOW ANOTHER...STRONGER...SHORTWAVE MOVING THROUGH THE REGION BETWEEN TUE EVENING AND WED AFTERNOON. MODELS CONTINUE TO DISAGREE ON STRENGTH OF THE SHORTWAVE...SO TIMING/COVERAGE/AMOUNTS OF PRECIP ARE UNCERTAIN. COULD SEE SOME GREATER PRECIP AMOUNTS (GFS AND NAM SHOWING UPWARDS OF ONLY 0.2 INCHES)...BUT MOST OF THAT SHOULD FALL AS RAIN. COULD SEE SOME VERY MINOR MEASURABLE SNOW...BUT INSIGNIFICANT REALLY. PRECIP ASSOCIATED WITH NEXT SHORTWAVE LOOKS TO MOVE IN LATE WED NIGHT. MAY SEE PRECIP CONFINED TO THE NRN CWA AHEAD OF THE SYSTEM THROUGH THU MORNING...THE WILL BE MORE LIKELY TO COVER MOST OF THE AREA THU AFTERNOON INTO THU NIGHT. COULD SEE SOME MINOR MEASURABLE SNOW OVER THE W THU EVENING INTO THU NIGHT...BUT DETAILS ARE STILL TOO SKETCHY TO SAY WITH CONFIDENCE. STILL SEE SOME POTENTIAL FOR A STRONGER SYSTEM TO MOVE THROUGH LATER NEXT WEEKEND...BUT THAT IS HIGHLY UNCERTAIN. MODELS DO CONTINUE TO SHOW COLDER AIR CAPABLE OF SUPPORTING LES AS THE WEEKEND GOES ON...BUT EXACT EXTENT AND EVEN WIND DIRECTION IS UNCERTAIN. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 125 PM EST MON DEC 7 2015 PERSISTENT LOW LEVEL SRLY UPSLOPE FLOW ALONG WITH ABUNDANT LOW LEVEL MOISTURE ACROSS THE REGION WILL SUSTAIN LIFR TO OCNLY VLIFR CONDITIONS THROUGH MOST OF THE TAF PERIOD. SOME DRIZZLE OR FREEZING DRIZZLE MAY ALSO BE POSSIBLE LATE TONIGHT INTO TUE MORNING. AT IWD/CMX...A MORE DOWNSLOPE WIND DIRECTION WILL KEEP MAINLY VFR CONDITIONS UNTIL LATER THIS EVENING WHEN NOCTURNAL COOLING WILL HELP SUPPORT STRATUS FORMATION WITH IFR CIGS. CONDITIONS WILL ONLY GRADUALLY IMPROVE TUE MORNING. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 310 AM EST MON DEC 7 2015 THE PRESSURE GRADIENT WILL INCREASE THIS AFTERNOON INTO TONIGHT AS A LOW PRESSURE SYSTEM MOVES INTO NW ONTARIO. THIS WILL SUPPORT A PERIOD OF 25-30 KNOT WIND GUSTS TONIGHT INTO TUE MORNING. ANOTHER PERIOD OF SOUTHERLY 25 KNOT WINDS IS EXPECTED THU INTO THU NIGHT AHEAD OF A LOW PRESSURE SYSTEM MOVING INTO THE UPPER MS VALLEY. OTHERWISE...WINDS WILL REMAIN BELOW 25 KNOTS. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...KC LONG TERM...TITUS AVIATION...JLB MARINE...TITUS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
633 AM EST MON DEC 7 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 353 AM EST MON DEC 7 2015 00Z RAOBS/LATEST WV IMAGERY AND RAP ANALYSIS SHOW A ZONAL SPLIT FLOW OF PACIFIC AIR OVER SRN CANADA AND THE CONUS. SHRTWV RDG AXIS IS MOVING INTO THE WRN GREAT LKS EARLY THIS MRNG...WITH WEAK SFC HI PRES RDG STRETCHING FM NW ONTARIO ACRS WRN UPR MI TO STRONGER HI PRES CENTERED OVER THE SRN PLAINS. ALTHOUGH THE AIRMASS OVHD IS DRY...WITH 00Z PWAT AS LO AS ABOUT 0.20 INCH AT MPX...LINGERING LLVL MSTR SHOWN ON LOCAL 00Z RAOBS TRAPPED UNDER LO SUBSIDENCE INVRN IS CAUSING QUITE A BIT OF LO CLD/FOG OVER MUCH OF THE CWA IN THE PRESENCE OF NOCTURNAL COOLING. THE FOG/STRATUS IS MOST EXTENSIVE OVER THE INTERIOR W HALF OF THE CWA...WITH MORE HIER BASED SC LINGERING OVER THE E...WHERE THE 00Z GRB/APX RAOBS SHOW MORE MSTR NEAR HIER INVRN BASE. AREAS NEAR LK SUP W OF MUNISING...EXCEPT FOR THE KEWEENAW...AND OVER THE SCENTRAL E OF IRON MTN ARE MOCLR... PROBABLY DUE TO LIGHT DOWNSLOPE W TO SW WINDS IN THESE AREAS. THE LO CLD AND FOG STRETCH W THRU MUCH OF MN. MORE HI CLD IN COMMA TAIL OF NRN BRANCH SHRTWV/SFC LO TRACKING INTO MANITBOA IS STREAMING E INTO MN AS WELL...BUT VERY DRY AIRMASS SHOWN ON THE ABERDEEN SDAKOTA AND BISMARCK RAOBS IS PREVENTING ANY PCPN OR EVEN LOWER CLDS. MAIN FCST CONCERNS IN THE SHORT TERM ARE FOCUSED ON FOG/LO CLD TRENDS. TODAY...AS SFC HI PRES RDG SHIFTS TO THE E AND LO PRES MOVES INTO NW ONTARIO...EXPECT A STEADY S WIND TO DVLP OVER UPR MI. NAM H95 RH... WHICH HAS A GOOD HANDLE ON THE AREA OF LO CLDS RIGHT NOW...HINTS THE AREA OF LO CLDS WL EXPAND TO ALL BUT THE NW CWA...WHERE THE S WIND DOWNSLOPES. WHILE DAYTIME HEATING WL LIKELY LIMIT FOG COVERAGE...LO SUN ANGLE WL PROBABLY NOT BE SUFFICIENT TO MIX OUT THE LO CLD. SO TENDED TOWARD MORE CLD COVER EXCEPT IN THOSE DOWNSLOPE AREAS NEAR LK SUP FM MUNISING TO BARAGA/THE KEWEENAW...ONTONAGON AND IRONWOOD. LOWERED FCST MAX TEMPS A COUPLE DEGREES WHERE THE LO CLD IS EXPECTED TO BE MOST EXTENSIVE. EXPECT THE WARMEST TEMPS INTO THE 40S IN THE DOWNSLOPE AREAS NEAR LK SUP. TNGT...AXIS OF DEEP LYR QVECTOR CNVGC IN COMMA TAIL OF SHRTWV MOVING TO THE ENE TOWARD HUDSON BAY IS FCST TO SHIFT W-E ACRS THE CWA. ALTHOUGH THIS FORCING WL NOT BE SUFFICIENT TO SATURATE THE VERY DRY MID LVLS...LIFTING OF THE SUBSIDENCE INVRN WL ALLOW FOR A GREATER DEPTH OF LLVL MSTR. MANY OF THE HIER RES MODELS GENERATE SOME LGT PCPN...ESPECIALLY IN AREAS DOWNWIND OF LK MI IN THE EXPECTED LLVL SSW FLOW. WL RETAIN SOME LO CHC POPS FOR DRIZZLE AND ADD SOME FOG IN THE FCST FOR THIS AREA. THE SOMEWHAT HIER INVRN BASE WL ALSO ALLOW FOR MORE LO CLDS TO EXPAND EVEN INTO THE DOWNSLOPE AREAS NEAR LK SUP. TEMPS WL RUN WELL ABOVE NORMAL...MAINLY IN THE 30S...WARMEST DOWNWIND OF LK MI. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 310 AM EST MON DEC 7 2015 LONG TERM WILL SEE SEVERAL SHORTWAVES MAKING FOR A BUSIER PATTERN...BUT AT THIS TIME PRECIP AMOUNTS LOOK TO BE MOSTLY INSIGNIFICANT. MAY SEE SOME MORE SIGNIFICANT PRECIP NEXT WEEKEND...BUT PREDICTABILITY IS QUITE LOW. MAY SEE SOME LIGHT PRECIP OVER THE E ON TUE...MAINLY TUE MORNING...AS A SHORTWAVE PASSES THROUGH. MODELS SHOW ANOTHER...STRONGER...SHORTWAVE MOVING THROUGH THE REGION BETWEEN TUE EVENING AND WED AFTERNOON. MODELS CONTINUE TO DISAGREE ON STRENGTH OF THE SHORTWAVE...SO TIMING/COVERAGE/AMOUNTS OF PRECIP ARE UNCERTAIN. COULD SEE SOME GREATER PRECIP AMOUNTS (GFS AND NAM SHOWING UPWARDS OF ONLY 0.2 INCHES)...BUT MOST OF THAT SHOULD FALL AS RAIN. COULD SEE SOME VERY MINOR MEASURABLE SNOW...BUT INSIGNIFICANT REALLY. PRECIP ASSOCIATED WITH NEXT SHORTWAVE LOOKS TO MOVE IN LATE WED NIGHT. MAY SEE PRECIP CONFINED TO THE NRN CWA AHEAD OF THE SYSTEM THROUGH THU MORNING...THE WILL BE MORE LIKELY TO COVER MOST OF THE AREA THU AFTERNOON INTO THU NIGHT. COULD SEE SOME MINOR MEASURABLE SNOW OVER THE W THU EVENING INTO THU NIGHT...BUT DETAILS ARE STILL TOO SKETCHY TO SAY WITH CONFIDENCE. STILL SEE SOME POTENTIAL FOR A STRONGER SYSTEM TO MOVE THROUGH LATER NEXT WEEKEND...BUT THAT IS HIGHLY UNCERTAIN. MODELS DO CONTINUE TO SHOW COLDER AIR CAPABLE OF SUPPORTING LES AS THE WEEKEND GOES ON...BUT EXACT EXTENT AND EVEN WIND DIRECTION IS UNCERTAIN. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 632 AM EST MON DEC 7 2015 AN INCRSG S WIND WL SHIFT FOG/LIFR TO VLIFR CONDITIONS IMPACTING CMX THIS MRNG TO THE N AND BRING A RETURN OF VFR WX THERE BY LATE MRNG. BUT AT SAW...THE MORE FAVORABLE UPSLOPE S WIND WL DRAW LO CLDS/IFR TO LIFR CONDITIONS INTO THAT SITE THIS MRNG. SHARPER DOWNSLOPE WIND COMPONENT SHOULD BRING VFR CONDITIONS TO IWD THRU THE DAY. AS THE S WIND STRENGTHENS AND DRAWS MOISTER AIR INTO THE UPR LKS TNGT IN THE PRESENCE OF NOCTURNAL COOLING...LO CLDS AND MVFR/IFR CIGS WL SPREAD INTO IWD AND CMX. EXPECT THE IFR CIGS TO PERSIST AT SAW AS WELL. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 310 AM EST MON DEC 7 2015 THE PRESSURE GRADIENT WILL INCREASE THIS AFTERNOON INTO TONIGHT AS A LOW PRESSURE SYSTEM MOVES INTO NW ONTARIO. THIS WILL SUPPORT A PERIOD OF 25-30 KNOT WIND GUSTS TONIGHT INTO TUE MORNING. ANOTHER PERIOD OF SOUTHERLY 25 KNOT WINDS IS EXPECTED THU INTO THU NIGHT AHEAD OF A LOW PRESSURE SYSTEM MOVING INTO THE UPPER MS VALLEY. OTHERWISE...WINDS WILL REMAIN BELOW 25 KNOTS. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...KC LONG TERM...TITUS AVIATION...KC MARINE...TITUS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
353 AM EST MON DEC 7 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 353 AM EST MON DEC 7 2015 00Z RAOBS/LATEST WV IMAGERY AND RAP ANALYSIS SHOW A ZONAL SPLIT FLOW OF PACIFIC AIR OVER SRN CANADA AND THE CONUS. SHRTWV RDG AXIS IS MOVING INTO THE WRN GREAT LKS EARLY THIS MRNG...WITH WEAK SFC HI PRES RDG STRETCHING FM NW ONTARIO ACRS WRN UPR MI TO STRONGER HI PRES CENTERED OVER THE SRN PLAINS. ALTHOUGH THE AIRMASS OVHD IS DRY...WITH 00Z PWAT AS LO AS ABOUT 0.20 INCH AT MPX...LINGERING LLVL MSTR SHOWN ON LOCAL 00Z RAOBS TRAPPED UNDER LO SUBSIDENCE INVRN IS CAUSING QUITE A BIT OF LO CLD/FOG OVER MUCH OF THE CWA IN THE PRESENCE OF NOCTURNAL COOLING. THE FOG/STRATUS IS MOST EXTENSIVE OVER THE INTERIOR W HALF OF THE CWA...WITH MORE HIER BASED SC LINGERING OVER THE E...WHERE THE 00Z GRB/APX RAOBS SHOW MORE MSTR NEAR HIER INVRN BASE. AREAS NEAR LK SUP W OF MUNISING...EXCEPT FOR THE KEWEENAW...AND OVER THE SCENTRAL E OF IRON MTN ARE MOCLR... PROBABLY DUE TO LIGHT DOWNSLOPE W TO SW WINDS IN THESE AREAS. THE LO CLD AND FOG STRETCH W THRU MUCH OF MN. MORE HI CLD IN COMMA TAIL OF NRN BRANCH SHRTWV/SFC LO TRACKING INTO MANITBOA IS STREAMING E INTO MN AS WELL...BUT VERY DRY AIRMASS SHOWN ON THE ABERDEEN SDAKOTA AND BISMARCK RAOBS IS PREVENTING ANY PCPN OR EVEN LOWER CLDS. MAIN FCST CONCERNS IN THE SHORT TERM ARE FOCUSED ON FOG/LO CLD TRENDS. TODAY...AS SFC HI PRES RDG SHIFTS TO THE E AND LO PRES MOVES INTO NW ONTARIO...EXPECT A STEADY S WIND TO DVLP OVER UPR MI. NAM H95 RH... WHICH HAS A GOOD HANDLE ON THE AREA OF LO CLDS RIGHT NOW...HINTS THE AREA OF LO CLDS WL EXPAND TO ALL BUT THE NW CWA...WHERE THE S WIND DOWNSLOPES. WHILE DAYTIME HEATING WL LIKELY LIMIT FOG COVERAGE...LO SUN ANGLE WL PROBABLY NOT BE SUFFICIENT TO MIX OUT THE LO CLD. SO TENDED TOWARD MORE CLD COVER EXCEPT IN THOSE DOWNSLOPE AREAS NEAR LK SUP FM MUNISING TO BARAGA/THE KEWEENAW...ONTONAGON AND IRONWOOD. LOWERED FCST MAX TEMPS A COUPLE DEGREES WHERE THE LO CLD IS EXPECTED TO BE MOST EXTENSIVE. EXPECT THE WARMEST TEMPS INTO THE 40S IN THE DOWNSLOPE AREAS NEAR LK SUP. TNGT...AXIS OF DEEP LYR QVECTOR CNVGC IN COMMA TAIL OF SHRTWV MOVING TO THE ENE TOWARD HUDSON BAY IS FCST TO SHIFT W-E ACRS THE CWA. ALTHOUGH THIS FORCING WL NOT BE SUFFICIENT TO SATURATE THE VERY DRY MID LVLS...LIFTING OF THE SUBSIDENCE INVRN WL ALLOW FOR A GREATER DEPTH OF LLVL MSTR. MANY OF THE HIER RES MODELS GENERATE SOME LGT PCPN...ESPECIALLY IN AREAS DOWNWIND OF LK MI IN THE EXPECTED LLVL SSW FLOW. WL RETAIN SOME LO CHC POPS FOR DRIZZLE AND ADD SOME FOG IN THE FCST FOR THIS AREA. THE SOMEWHAT HIER INVRN BASE WL ALSO ALLOW FOR MORE LO CLDS TO EXPAND EVEN INTO THE DOWNSLOPE AREAS NEAR LK SUP. TEMPS WL RUN WELL ABOVE NORMAL...MAINLY IN THE 30S...WARMEST DOWNWIND OF LK MI. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 310 AM EST MON DEC 7 2015 LONG TERM WILL SEE SEVERAL SHORTWAVES MAKING FOR A BUSIER PATTERN...BUT AT THIS TIME PRECIP AMOUNTS LOOK TO BE MOSTLY INSIGNIFICANT. MAY SEE SOME MORE SIGNIFICANT PRECIP NEXT WEEKEND...BUT PREDICTABILITY IS QUITE LOW. MAY SEE SOME LIGHT PRECIP OVER THE E ON TUE...MAINLY TUE MORNING...AS A SHORTWAVE PASSES THROUGH. MODELS SHOW ANOTHER...STRONGER...SHORTWAVE MOVING THROUGH THE REGION BETWEEN TUE EVENING AND WED AFTERNOON. MODELS CONTINUE TO DISAGREE ON STRENGTH OF THE SHORTWAVE...SO TIMING/COVERAGE/AMOUNTS OF PRECIP ARE UNCERTAIN. COULD SEE SOME GREATER PRECIP AMOUNTS (GFS AND NAM SHOWING UPWARDS OF ONLY 0.2 INCHES)...BUT MOST OF THAT SHOULD FALL AS RAIN. COULD SEE SOME VERY MINOR MEASURABLE SNOW...BUT INSIGNIFICANT REALLY. PRECIP ASSOCIATED WITH NEXT SHORTWAVE LOOKS TO MOVE IN LATE WED NIGHT. MAY SEE PRECIP CONFINED TO THE NRN CWA AHEAD OF THE SYSTEM THROUGH THU MORNING...THE WILL BE MORE LIKELY TO COVER MOST OF THE AREA THU AFTERNOON INTO THU NIGHT. COULD SEE SOME MINOR MEASURABLE SNOW OVER THE W THU EVENING INTO THU NIGHT...BUT DETAILS ARE STILL TOO SKETCHY TO SAY WITH CONFIDENCE. STILL SEE SOME POTENTIAL FOR A STRONGER SYSTEM TO MOVE THROUGH LATER NEXT WEEKEND...BUT THAT IS HIGHLY UNCERTAIN. MODELS DO CONTINUE TO SHOW COLDER AIR CAPABLE OF SUPPORTING LES AS THE WEEKEND GOES ON...BUT EXACT EXTENT AND EVEN WIND DIRECTION IS UNCERTAIN. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1224 AM EST MON DEC 7 2015 LOW CLOUDS AND FOG HAVE MOVED INTO KSAW AS EXPECTED...BUT BOTH LOWER THAN ORIGINALLY EXPECTED WITH LIFR/VLIFR CONDITIONS THERE. MEANWHILE KCMX HAS CLEARED OUT. SOME MIST DEVELOPING AT BOTH KCMX AND KIWD...BUT AT THIS TIME DO NOT EXPECT ANY SGNFT IMPACTS AT EITHER SITE...BUT KIWD NEEDS TO BE MONITORED CLOSELY DUE TO PROXIMITY OF ST/FG JUST TO THE SOUTHEAST. VSBYS HAVE DROPPED TO IFR/VIFR OVER PORTIONS OF THE CENTRAL U.P. AND THIS HAS IMPACTED KSAW THIS MORNING. EXPECT THESE VSBYS TO IMPROVE TO MVFR SHORTLY AFTER SUNRISE WITH THE FOG DISSIPATING SHORTLY THEREAFTER. VFR CONDITIONS SHOULD THEN PREVAIL OVER THE AREA UNTIL LOW CLOUDS MAKE A RETURN TO KSAW LATE IN THE FORECAST. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 310 AM EST MON DEC 7 2015 THE PRESSURE GRADIENT WILL INCREASE THIS AFTERNOON INTO TONIGHT AS A LOW PRESSURE SYSTEM MOVES INTO NW ONTARIO. THIS WILL SUPPORT A PERIOD OF 25-30 KNOT WIND GUSTS TONIGHT INTO TUE MORNING. ANOTHER PERIOD OF SOUTHERLY 25 KNOT WINDS IS EXPECTED THU INTO THU NIGHT AHEAD OF A LOW PRESSURE SYSTEM MOVING INTO THE UPPER MS VALLEY. OTHERWISE...WINDS WILL REMAIN BELOW 25 KNOTS. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...KC LONG TERM...TITUS AVIATION...RJT MARINE...TITUS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
313 AM EST MON DEC 7 2015 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 405 PM EST SUN DEC 6 2015 WV IMAGERY AND RAP ANALYSIS INDICATED A SPLIT FLOW PATTERN ACROSS NORTH AMERICA WITH A SRN STREAM MID LEVEL LOW OVER ILLINOIS AND THE ACTIVE PORTION OF THE NRN STREAM BRANCH WELL TO THE NORTH THROUGH NRN ONTARIO AND JAMES BAY. THE NRN ONTARIO SHRTWV HAS DRAGGED A WEAK COLD FRONT THROUGH THE NRN LAKES WITH DRIER AIR AND ACYC COMBINED WITH DAYTIME MIXING HELPING TO SCOUR OUT THE LOW CLOUDS OVER MUCH OF UPPER MICHIGAN...EXCEPT OVER THE KEWEENAW AND THE EAST. TONIGHT...THE MODELS SHOW MID LEVEL AND SFC RIDGING BUILDING INTO THE WRN LAKES TONIGHT WITH PWAT VALUES DROPPING AOB 0.25 INCH OVER MUCH OF UPPER MICHIGAN. ALTHOUGH THERE MAY BE A PERIOD OF CLEARING INTO THIS EVENING...EXPECT THAT WITH FAVORABLE RADIATIONAL COOLING CONDITIONS AND LINGERING LOW LEVEL MOISTURE WITH DEWPOINTS FROM LATE AFTERNOON IN THE LOWER 30S...AREAS OF FOG WILL DEVELOP. ISOLD DENSE FOG WILL ALSO BE POSSIBLE...BUT CONFIDENCE IN TIMING/LOCATIONS IS NOT AS HIGH. DEVELOPING DOWNSLOPE SSW LOW LEVEL FLOW OVER THE WEST WILL LIMIT FOG POTENTIAL IN THE WEST HALF NEAR LAKE SUPERIOR. MONDAY...HIGHER RES MODELS 925MB RH FCST SUGGESTS THAT ADDITIONAL SW FLOW DRY ADVECTION ALONG WITH LIMITED WINTER TIME DAYTIME WILL BE ENOUGH TO AGAIN SCOUR OUT ANY LEFTOVER CLOUDS/FOG DURING THE MORNING. THIS SHOULD ALLOW TEMPS TO CLIMB INTO THE LOW TO MID 40S WITH UPPER 40S WITH DOWNSLOPE FLOW NEAR LAKE SUPERIOR. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 310 AM EST MON DEC 7 2015 LONG TERM WILL SEE SEVERAL SHORTWAVES MAKING FOR A BUSIER PATTERN...BUT AT THIS TIME PRECIP AMOUNTS LOOK TO BE MOSTLY INSIGNIFICANT. MAY SEE SOME MORE SIGNIFICANT PRECIP NEXT WEEKEND...BUT PREDICTABILITY IS QUITE LOW. MAY SEE SOME LIGHT PRECIP OVER THE E ON TUE...MAINLY TUE MORNING...AS A SHORTWAVE PASSES THROUGH. MODELS SHOW ANOTHER...STRONGER...SHORTWAVE MOVING THROUGH THE REGION BETWEEN TUE EVENING AND WED AFTERNOON. MODELS CONTINUE TO DISAGREE ON STRENGTH OF THE SHORTWAVE...SO TIMING/COVERAGE/AMOUNTS OF PRECIP ARE UNCERTAIN. COULD SEE SOME GREATER PRECIP AMOUNTS (GFS AND NAM SHOWING UPWARDS OF ONLY 0.2 INCHES)...BUT MOST OF THAT SHOULD FALL AS RAIN. COULD SEE SOME VERY MINOR MEASURABLE SNOW...BUT INSIGNIFICANT REALLY. PRECIP ASSOCIATED WITH NEXT SHORTWAVE LOOKS TO MOVE IN LATE WED NIGHT. MAY SEE PRECIP CONFINED TO THE NRN CWA AHEAD OF THE SYSTEM THROUGH THU MORNING...THE WILL BE MORE LIKELY TO COVER MOST OF THE AREA THU AFTERNOON INTO THU NIGHT. COULD SEE SOME MINOR MEASURABLE SNOW OVER THE W THU EVENING INTO THU NIGHT...BUT DETAILS ARE STILL TOO SKETCHY TO SAY WITH CONFIDENCE. STILL SEE SOME POTENTIAL FOR A STRONGER SYSTEM TO MOVE THROUGH LATER NEXT WEEKEND...BUT THAT IS HIGHLY UNCERTAIN. MODELS DO CONTINUE TO SHOW COLDER AIR CAPABLE OF SUPPORTING LES AS THE WEEKEND GOES ON...BUT EXACT EXTENT AND EVEN WIND DIRECTION IS UNCERTAIN. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1224 AM EST MON DEC 7 2015 LOW CLOUDS AND FOG HAVE MOVED INTO KSAW AS EXPECTED...BUT BOTH LOWER THAN ORIGINALLY EXPECTED WITH LIFR/VLIFR CONDITIONS THERE. MEANWHILE KCMX HAS CLEARED OUT. SOME MIST DEVELOPING AT BOTH KCMX AND KIWD...BUT AT THIS TIME DO NOT EXPECT ANY SGNFT IMPACTS AT EITHER SITE...BUT KIWD NEEDS TO BE MONITORED CLOSELY DUE TO PROXIMITY OF ST/FG JUST TO THE SOUTHEAST. VSBYS HAVE DROPPED TO IFR/VIFR OVER PORTIONS OF THE CENTRAL U.P. AND THIS HAS IMPACTED KSAW THIS MORNING. EXPECT THESE VSBYS TO IMPROVE TO MVFR SHORTLY AFTER SUNRISE WITH THE FOG DISSIPATING SHORTLY THEREAFTER. VFR CONDITIONS SHOULD THEN PREVAIL OVER THE AREA UNTIL LOW CLOUDS MAKE A RETURN TO KSAW LATE IN THE FORECAST. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 310 AM EST MON DEC 7 2015 THE PRESSURE GRADIENT WILL INCREASE THIS AFTERNOON INTO TONIGHT AS A LOW PRESSURE SYSTEM MOVES INTO NW ONTARIO. THIS WILL SUPPORT A PERIOD OF 25-30 KNOT WIND GUSTS TONIGHT INTO TUE MORNING. ANOTHER PERIOD OF SOUTHERLY 25 KNOT WINDS IS EXPECTED THU INTO THU NIGHT AHEAD OF A LOW PRESSURE SYSTEM MOVING INTO THE UPPER MS VALLEY. OTHERWISE...WINDS WILL REMAIN BELOW 25 KNOTS. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...TITUS AVIATION...RJT MARINE...TITUS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1225 AM EST MON DEC 7 2015 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 405 PM EST SUN DEC 6 2015 WV IMAGERY AND RAP ANALYSIS INDICATED A SPLIT FLOW PATTERN ACROSS NORTH AMERICA WITH A SRN STREAM MID LEVEL LOW OVER ILLINOIS AND THE ACTIVE PORTION OF THE NRN STREAM BRANCH WELL TO THE NORTH THROUGH NRN ONTARIO AND JAMES BAY. THE NRN ONTARIO SHRTWV HAS DRAGGED A WEAK COLD FRONT THROUGH THE NRN LAKES WITH DRIER AIR AND ACYC COMBINED WITH DAYTIME MIXING HELPING TO SCOUR OUT THE LOW CLOUDS OVER MUCH OF UPPER MICHIGAN...EXCEPT OVER THE KEWEENAW AND THE EAST. TONIGHT...THE MODELS SHOW MID LEVEL AND SFC RIDGING BUILDING INTO THE WRN LAKES TONIGHT WITH PWAT VALUES DROPPING AOB 0.25 INCH OVER MUCH OF UPPER MICHIGAN. ALTHOUGH THERE MAY BE A PERIOD OF CLEARING INTO THIS EVENING...EXPECT THAT WITH FAVORABLE RADIATIONAL COOLING CONDITIONS AND LINGERING LOW LEVEL MOISTURE WITH DEWPOINTS FROM LATE AFTERNOON IN THE LOWER 30S...AREAS OF FOG WILL DEVELOP. ISOLD DENSE FOG WILL ALSO BE POSSIBLE...BUT CONFIDENCE IN TIMING/LOCATIONS IS NOT AS HIGH. DEVELOPING DOWNSLOPE SSW LOW LEVEL FLOW OVER THE WEST WILL LIMIT FOG POTENTIAL IN THE WEST HALF NEAR LAKE SUPERIOR. MONDAY...HIGHER RES MODELS 925MB RH FCST SUGGESTS THAT ADDITIONAL SW FLOW DRY ADVECTION ALONG WITH LIMITED WINTER TIME DAYTIME WILL BE ENOUGH TO AGAIN SCOUR OUT ANY LEFTOVER CLOUDS/FOG DURING THE MORNING. THIS SHOULD ALLOW TEMPS TO CLIMB INTO THE LOW TO MID 40S WITH UPPER 40S WITH DOWNSLOPE FLOW NEAR LAKE SUPERIOR. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 326 PM EST SUN DEC 6 2015 MUCH OF THIS PERIOD WILL BE MARKED BY 500MB WAVES IN WHAT GENERALLY LOOKS LIKE ZONAL FLOW...WITH A SERIES OF WEAK SFC LOWS SPINNING ACROSS CANADA IMPACTING THE UPPER GREAT LAKES THROUGH THE WORK WEEK. OVERALL LIGHT PRECIP IS ANTICIPATED. BY 00Z TUESDAY THE INITIAL 500MB TROUGH WILL BE WELL TO OUR E /OVER PA/...WITH AN EXITING RIDGE OVER THE UPPER GREAT LAKES AHEAD OF THE NEXT TROUGH SET UP FROM N MANITOBA THROUGH MN/IA. A BROAD SFC LOW WAS OVER MUCH OF W AND CENTRAL CANADA. THE E LOBE OF THIS TROUGH WILL BE ACROSS N ONTARIO...DROPPING A COLD FRONT ACROSS OUR AREA. THE RESULT WILL BE INCREASED MID AND HIGH CLOUDS THAT WILL CONTINUE INTO EARLY WEDNESDAY MORNING. WHILE FCST MODELS DO INDICATE SOME CHANCE OF PRECIPITATION...MUCH OF THAT IS LIGHT AND OVER THE E HALF OF THE CWA. THERE WILL BE AS AN ADDITIONAL TROUGH IN THE BROAD CANADIAN LOW SWINGS ACROSS S MANITOBA/ND TUESDAY AFTERNOON AND OVER THE UPPER GREAT LAKES WEDNESDAY MORNING. ZONAL FLOW/SLIGHT RIDGING BRIEFLY TAKES HOLD LATE WEDNESDAY AFTERNOON INTO WEDNESDAY EVENING...WHILE THE NEXT 500MB TROUGH SETS UP OVER S SASKATCHEWAN/MT. THE LAST AND STRONGEST PART OF THE CANADIAN LOW WILL BE OVER S CENTRAL CANADA AT 06Z THURSDAY. LOOK FOR THIS LOW TO SHIFT ACROSS N MN THURSDAY MORNING AND THEN ACROSS N LAKE SUPERIOR/ONTARIO THURSDAY EVENING. THE LOW WILL CONTINUE TO TRACK TO AROUND JAMES BAY BY 18Z FRIDAY. THERE ARE SOME DISCREPANCIES...AS THE GFS AND CANADIAN RUNS EJECT THE LOW TO THE NE MUCH QUICKER THAN THE 00Z RUN OF THE ECMWF FRIDAY NIGHT. THE 12Z ECMWF SPED THE SYSTEM UP A BIT...BUT IT/S STILL ON THE SLOW SIDE. JUST HOW MUCH MOISTURE WILL BE ABLE TO SURGE N INTO OUR AREA IS ALSO IN QUESTION. THE SLOWER ECMWF GIVES MORE TIME FOR MOISTURE TO POOL TO OUR S...AND MOVE OVERHEAD THURSDAY NIGHT. THE RESULT IS LOWER THAN AVERAGE CONFIDENCE IN THE ONGOING FCST FROM FRIDAY ON. A MORE ROBUST SYSTEM SHOULD SET UP OVER THE W HALF OF THE NATION SATURDAY...IN THE FORM OF A SIGNIFICANT 500MB TROUGH. EXACTLY WHERE THE SFC LOW SETS UP IS STILL A CONCERN AS THE 00Z RUN OF THE ECMWF TIES IT TO THE SLOWER LOW IMPACTING OUR WEATHER THURSDAY INTO EARLY FRIDAY. THE 12Z ECMWF SETS UP THE SECONDARY LOW WELL TO THE S. THE GFS ON THE OTHER HAND HAS A STRONGER SFC LOW OVER THE CENTRAL PLAINS AT 00Z SATURDAY MOVING ACROSS OUR AREA SATURDAY NIGHT. THE RESULT IS MUCH MORE QPF OFF THE GFS...WHILE THE ECMWF PUSHES THE SWATH OF HIGHEST PRECIP OVER LOWER MI SATURDAY NIGHT. EITHER WAY...COLD AIR LOOKS POISED TO SLIDE IN FOR THE END OF THE WEEKEND WITH 850MB TEMPS OF -5 TO -12C BY 00Z MONDAY ON W TO NNW WINDS. RIGHT NOW IT LOOKS LIKE WE WILL AT LEAST TEMPORARILY BREAK OUR TREND OF ABOVE NORMAL TEMPERATURES. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1224 AM EST MON DEC 7 2015 LOW CLOUDS AND FOG HAVE MOVED INTO KSAW AS EXPECTED...BUT BOTH LOWER THAN ORIGINALLY EXPECTED WITH LIFR/VLIFR CONDITIONS THERE. MEANWHILE KCMX HAS CLEARED OUT. SOME MIST DEVELOPING AT BOTH KCMX AND KIWD...BUT AT THIS TIME DO NOT EXPECT ANY SGNFT IMPACTS AT EITHER SITE...BUT KIWD NEEDS TO BE MONITORED CLOSELY DUE TO PROXIMITY OF ST/FG JUST TO THE SOUTHEAST. VSBYS HAVE DROPPED TO IFR/VIFR OVER PORTIONS OF THE CENTRAL U.P. AND THIS HAS IMPACTED KSAW THIS MORNING. EXPECT THESE VSBYS TO IMPROVE TO MVFR SHORTLY AFTER SUNRISE WITH THE FOG DISSIPATING SHORTLY THEREAFTER. VFR CONDITIONS SHOULD THEN PREVAIL OVER THE AREA UNTIL LOW CLOUDS MAKE A RETURN TO KSAW LATE IN THE FORECAST. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 405 PM EST SUN DEC 6 2015 THE PRES GRADIENT WILL INCREASE MON NIGHT WITH THE RIDGE SLIDING TO THE EAST AND LOW PRES MOVING INTO NW ONTARIO. THIS WILL SUPPORT A PERIOD OF 25 KNOT WINDS. ANOTHER PERIOD OF SRLY 25 KNOT WINDS IS EXPECTED THU AHEAD OF LOW PRES MOVING INTO THE UPPER MS VALLEY. OTHERWISE...WINDS WILL REMAIN BELOW 25 KNOTS. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...KF AVIATION...RJT MARINE...JLB
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
1153 PM EST SUN DEC 6 2015 .AVIATION... EXTENSIVE REGION OF LOW STRATUS AND FOG NOW ENCOMPASSING THE ENTIRE SOUTHEAST MICHIGAN AIRSPACE. LATEST TRENDS CONTINUE TO SUPPORT SEEING WIDESPREAD LIFR CONDITIONS THROUGH THE DURATION OF THE EARLY MORNING PERIOD. ADDITIONAL MOISTURE TIED TO AN INBOUND TROUGH NOW SHIFTING ACROSS LAKE MICHIGAN WILL ARRIVE BY MID-LATE MORNING. THIS MOISTURE WILL REINFORCE THE EXISTING LOW STRATUS FOR MONDAY...BUT FAVOR SOME IMPROVEMENT IN VSBY AS FLOW TURNS TO NORTHWEST. FOR DTW...LIFR STRATUS/FOG NOW IN PLACE WILL HOLD FIRM THROUGH THE MID MORNING PERIOD. THE EMERGENCE OF A LIGHT NORTHWEST FLOW WILL FAVOR SOME IMPROVEMENT IN CONDITIONS AFTER 14Z. IFR LEVEL RESTRICTIONS APPEAR LIKELY WELL INTO MONDAY UNDER CONTINUED LOW STRATUS. //DTW THRESHOLD PROBABILITIES... * HIGH IN VSBY/CIGS BELOW 1/2SM AND/OR 200 FT TONIGHT. * HIGH IN CIGS BELOW 5000 FT TONIGHT AND MONDAY. && .PREV DISCUSSION...ISSUED 804 PM EST SUN DEC 6 2015 UPDATE... ANOTHER CHALLENGING NIGHT FOR DELINEATING BOTH THE SCOPE AND LOCATION OF STRATUS VERSUS DENSE FOG. A RATHER AGGRESSIVE RESPONSE ALREADY UNDERWAY AGAIN TONIGHT AS THE NEAR SURFACE ENVIRONMENT QUICKLY SATURATES. 23Z HRRR VISIBILITY OUTPUT ON TARGET WITH CURRENT CONDITIONS...AND POINTS TOWARD A SIGNIFICANT EXPANSION OF FOG NORTH OF I-69 THROUGH 06Z. ALREADY SIGNS OF THIS FROM THE THUMB BACK INTO SAGINAW. ANOTHER REGION OF LOWER VISIBILITY NOTED CENTERED BETWEEN THE I-96 CORRIDOR AND THE OHIO BORDER. WHILE VISIBILITY HAS TANKED ACROSS PORTIONS OF THIS CORRIDOR...NOW NOTING A SUBTLE BUT PERHAPS IMPORTANT SHIFT IN WIND TO LIGHT NORTHWESTERLY. THE ADDED SLIGHT DOWNSLOPE OFF THE GLACIAL RIDGE MAY VERY WELL LEAVE THIS DENSE FOG AS A TEMPORARY/MORE LOCALIZED ISSUE...WITH A TREND TOWARD MORE OF A LOW STRATUS ISSUE. WILL CLOSELY MONITOR VISIBILITY TRENDS MOVING FORWARD TO DETERMINE THE NEED FOR AN ADVISORY ACROSS THIS CORRIDOR. GREATER CONCERN CURRENTLY ACROSS THE THUMB AND TRI-CITIES...GIVEN SUPPORTIVE MODEL AND SATELLITE EVIDENCE TO ADD CONFIDENCE FOR A WIDESSPREAD DENSE FOG EVENT OVERNIGHT. WILL GO AHEAD WITH AN ADVISORY FOR THIS CORRIDOR...WITH ROOM TO EXPAND SHOULD CONDITIONS WARRANT FOR POINTS TO THE SOUTH. PREV DISCUSSION...ISSUED 306 PM EST SUN DEC 6 2015 DISCUSSION... NEARLY A CARBON COPY RESULT OF SATURDAY ACROSS SOUTHEAST LOWER MICHIGAN - WITH A STUBBORN STRATUS DECK BANKED UP AGAINST THE GLACIAL RIDGE BENEATH A VERY STRONG NEAR SURFACE THERMAL INVERSION. AS A RESULT...THESE CLOUDS HAVE KEPT TEMPS DOWN SIGNIFICANTLY ACROSS NORTHERN AND WESTERN SECTIONS OF THE METRO REGION. AN ADDITIONAL MORE EXPANSIVE AREA OF STRATUS OVER THE CENTRAL LOWER PENINSULA HAS BEEN AFFECTING THE MIDLAND REGION. ELSEWHERE...AMPLE SUN HAS PROPELLED TEMPERATURES WELL INTO THE 40S. A WELL DEFINED MID-TROPOSPHERIC WAVE IS CURRENTLY CYCLING ACROSS CENTRAL ILLINOIS AND WILL PASS TO THE SOUTH OF LOWER MICHIGAN TONIGHT. AN INVERTED SURFACE TROUGH EXTENDING NORTHWARD ACROSS WISCONSIN...IN CONJUNCTION WITH A NARROW ELEVATED PV FILAMENT ATTACHING THE WAVE TO THE PARENT RESERVOIR OVER THE HUDSON BAY REGION...WILL SLIDE THROUGH THE REGION TONIGHT. THIS WILL SERVE TO TURN THE LIGHT FLOW TO MORE WESTERLY AND ALLOW FOR ADDITIONAL LOW- LEVEL MOISTURE ADVECTION BENEATH THE PERSISTENT INVERSION LAYER. SPECIFICALLY...A SUBSTANTIAL STRATUS PRESENCE IS NOTED UPSTREAM IN THE WAKE OF THE SURFACE TROUGH. WITH THE LOSS OF INSOLATION EARLY THIS EVENING...EXPECT THE CURRENT LOW CLOUD SHIELDS OVER AREA TO START TO EXPAND ONCE AGAIN. FOG DEVELOPMENT IS ALSO VERY LIKELY AS RADIATIONAL COOLING SHOULD BE MORE EFFICIENT TONIGHT DUE TO A LESSER DEGREE OF ELEVATED MOISTURE INTERCEPTING THE OUTGOING OPTICAL PATH. THE HRRR...RAP...AND TO A LESSER EXTENT NAM GUIDANCE ALL OFFER SOME DEPICTION OF BOTH AN EXPANDING CLOUD/FOG SCENARIO IN COMBINATION WITH THE UPSTREAM NEAR SURFACE MOISTURE ADVECTING INTO THE REGION OVERNIGHT. UNFORTUNATELY...THE VERY LOW CLOUDS WILL LIKELY PERSIST EVERYWHERE ON MONDAY...WHICH WILL GREATLY REDUCE MAX TEMPERATURE POTENTIAL. THE NAM AND REGIONAL GEM ARE OFFERING A VERY GLOOMY PICTURE RIGHT ON INTO TUESDAY. GIVEN THE INABILITY TO ERASE THE OMNIPRESENT INVERSION...A MORE PESSIMISTIC DEPICTION IS THE MOST LIKELY OUTCOME. THEREFORE...HAVE LOWERED HIGH TEMPERATURES ON MONDAY AND TUESDAY APPRECIABLY - CERTAINLY MUCH MORE THAN ANY GUIDANCE OFFERED BY THE GFS FAMILY...WHICH HAS NOT OFFERED ANY SKILL THUS FAR. THE NEXT CHANCE FOR MEASURABLE PRECIPITATION WILL COME LATER IN THE DAY ON TUESDAY AS SOME SEMBLANCE OF MID-LEVEL THETA-E ADVECTION COMMENCES WITH A WEAK UPPER-LEVEL RIPPLE. THIS IS ESPECIALLY TRUE ACROSS THE SAGINAW VALLEY AND THUMB REGIONS. THE NEXT WAVE OF DEEPER THETA-E ADVECTION ARRIVES EARLY WEDNESDAY WITH A MUCH BETTER DEFINED PACIFIC ORIGIN SHORTWAVE. THE MOISTURE QUALITY IS STILL RATHER LOW - GIVEN ANY RETURN FLOW OFF THE GULF OF MEXICO IS INACCESSIBLE. WEAK SURFACE RIDGING WILL KEEP US DRY FOR WEDNESDAY NIGHT AND MOST OF THURSDAY. A STRONGER LOW PRESSURE SYSTEM IS FORECASTED TO TRACK OVER THE NORTHERN GREAT LAKES ON THURSDAY NIGHT AND INTO FRIDAY. THIS LOW AND ASSOCIATED COLD FRONT WILL BRING ANOTHER SHOT AT SOME RAIN SHOWERS ON THURSDAY NIGHT AND INTO EARLY FRIDAY MORNING. FOR FRIDAY AND THE WEEKEND...THERE IS INCONSISTENCY AMONGST THE MODELS IN REGARDS TO THE NEXT WEATHER MAKER. FOR NOW...HAVE JUST KEPT IN HIGH CHANCE POPS /50 PERCENT/ FOR NEXT WEEKEND UNTIL THE MODELS CAN GET A BETTER HANDLE ON THE SYSTEM. ONE THING THAT IS FOR CERTAIN IS THAT TEMPERATURES WILL BE QUITE WARM /850 TEMPS IN THE 5 TO 10 DEGREE CELSIUS RANGE/ WHICH WILL RESULT IN PRECIPITATION TO BE ALL RAIN. MARINE... WINDS WILL VEER ACROSS THE CENTRAL LAKES REGION TONIGHT AS A WEAK SURFACE TROUGH PASSES. SPEEDS WILL ALSO DECREASE AS WEAK HIGH PRESSURE SLIPS IN BEHIND THE TROUGH. SOUTHWEST WINDS WILL RESUME AND INCREASE ONCE AGAIN ON TUESDAY IN ADVANCE OF THE NEXT SYSTEM THE RELATIVELY STABLE NEAR SURFACE CONDITIONS WILL KEEP THE WIND IN CHECK...BUT WILL STILL APPROACH 20KTS WITH SOME GUST POTENTIAL OVER THE OPEN WATERS AND SAGINAW BAY. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...DENSE FOG ADVISORY UNTIL 11 AM EST MONDAY FOR MIZ047>049-053>055- 060>063-068>070-075-076-082-083. LAKE HURON...NONE. LAKE ST CLAIR...NONE. MICHIGAN WATERS OF LAKE ERIE...NONE. && $$ AVIATION.....MR UPDATE.......MR DISCUSSION...MANN/RK MARINE.......MANN 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
914 PM CST TUE DEC 8 2015 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 342 PM CST TUE DEC 8 2015 GOOD PV ANOMALY WITH DRYING NOTED IN WATER VAPOR HAS HELPED FORCE A NICE BAND OF LIGHT RAIN ACROSS ERN MN/WRN WI TODAY. NORTH OF THE PV BOOT...THE COMBINATION OF FGEN IN THE H85-H7 LAYER AND ISENTROPIC LIFT ON THE 295K SFC HAVE PROVIDED THE FORCING FOR THE BAND OF RAIN WE SEE OUT THERE THIS AFTERNOON. THE HRRR HAS HAD A PRETTY GOOD HANDLE ON THIS RAIN...SO FOLLOWED IT FOR SHIPPING THIS BAND OF RAIN OUT OF THE EAST END OF THE MPX CWA BETWEEN 3Z AND 6Z. THIS WILL LIKELY BE IT FOR ANY MEANINGFUL PRECIP...THOUGH A FEW SPRINKLES WILL BE POSSIBLE UNTIL THE MAIN UPPER TROUGH AND ASSOCIATED SFC THROUGH CURRENTLY ENTERING WRN MN MOVE THROUGH. HOWEVER...THIS WAVE LOOKS TO LACK DEEP MOISTURE LIKE THE LEAD WAVE HAS...SO CONCENTRATED ANY MENTIONABLE POPS ON THE ERN WAVE. FOR TONIGHT...THE MAIN PLAYER TO WHAT WILL HAPPEN WITH TEMPERATURES AND THE POTENTIAL FOR FOG/STRATUS WILL BE THE NARROW STRIP OF CLEARING THAT IS STRADDLING THE WRN DAKOTAS BORDER. THIS CLEARING WILL WORK FROM WEST TO EAST ACROSS THE MPX AREA TONIGHT. DEPENDING ON WHEN THE CLEARING ARRIVES AND HOW LONG IT PERSISTS...COULD EASILY SEE LOWS A FEW DEGREES COOLER THAN WHAT WE CURRENTLY HAVE...ESPECIALLY ACROSS CENTRAL MN. THERE WILL ALSO BE THE POTENTIAL TO DEVELOP FOG/LOW STRATUS. HOWEVER...WITH SFC WINDS EXPECTED TO REMAIN UP IN THE 4-8KT RANGE BEHIND THE TROUGH...LIKELY MEANS OUR MAIN ISSUE FOR TONIGHT WOULD BE THE POTENTIAL FOR VERY LOW STRATUS AS OPPOSED TO FOG. THE HRRR DEVELOPS LOW STRATUS/FOG LATE TONIGHT OVER ERN MN/WRN WI...WHICH GIVEN THE CURRENT RAIN WOULD MAKE THE MOST SENSE FOR SEEING STRATUS/FOG IF WE ARE GOING TO SEE IT. FOR WEDNESDAY...ZONAL FLOW ALOFT WILL MEAN MORE MID/UPPER LEVEL CLOUDS...BUT ALSO THE RETURN OF VERY MILD AIR FROM THE CENTRAL PLAINS. BOUNDARY LAYER WINDS TOMORROW WILL BE FROM THE SW...WHICH IS A FAVORABLE WARMING DIRECTION. AS A RESULT...BOOSTED HIGHS SEVERAL DEGREES DOWNSTREAM OF THE BUFFALO RIDGE...WHERE WE ARE NOW ANTICIPATING HIGHS TO REACH INTO THE LOW TO MID 50S...WITH HIGHS AROUND 40 WITH THE REMNANT SNOWPACK OVER CENTRAL MN AND MID/UPPER 40S ELSEWHERE...THOUGH THIS COULD BE WARMER OUTSIDE OF THE REMNANT SNOW COVER. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 342 PM CST TUE DEC 8 2015 THE PATTERN WILL CONTINUE BECOMING MORE ACTIVE DURING THE LONG TERM. THE FIRST IN A SERIES OF SYSTEMS TO WATCH WILL BE TRACKING EASTWARD ALONG THE CANADIAN BORDER WEDNESDAY NIGHT AND THURSDAY. MODELS REMAIN IN FAIRLY GOOD AGREEMENT WITH THIS SYSTEM...WITH THE EXCEPTION OF THE EURO WHICH CONTINUES TO TRACK ON THE SOUTHERN EDGE OF THE ENVELOPE. THE MAJORITY OF THE CWA SHOULD BE DRY...WITH PRECIPITATION LIKELY TO OCCUR ALONG AND NORTH OF THE STORM TRACK. REDUCED POPS SOME...BUT MAINTAINED AT LEAST SOME MENTIONABLE POPS ACROSS THE ENTIRE CWA. HIGHEST POPS ARE CONFINED TO CENTRAL MN WHERE HIGH CHC OR LOW END LIKELIES CONTINUE. TO THE SOUTH OF THE TRACK...THE DRY SLOT SHOULD HELP CLEAR THE CLOUDS THURSDAY AFTERNOON ACROSS SRN MN AND WRN WI. STRONGEST CAA WILL LAG BEHIND THE SYSTEM...AND IT COULD GET RATHER MILD DEPENDING ON THE AMOUNT OF SUN. CANNOT RULE OUT LOWER 50S ACROSS SRN MN AND INTO WRN WI. WINDS WILL BE QUITE GUSTY WITH THE PASSAGE OF THE NEGATIVELY TILTED TROUGH...PARTICULARLY IF THE BOUNDARY LAYER DESTABILIZES WITH EITHER STRONGER CAA ALOFT...OR HEATING WITH SUN. THE DEVELOPING TROUGH ACROSS THE WESTERN U.S. THURSDAY INTO FRIDAY WILL PLAY A BIG ROLE IN THE REST OF THE LONG TERM FORECAST. ENERGY WILL BEGIN EJECTING OUT IN PIECES THURSDAY NIGHT WITH A LEADING WAVE ARRIVING LATE FRIDAY. THIS MAY BRING A SMALL CHANCE FOR PRECIPITATION...BUT IT DOES NOT HAVE THE TROPICAL MOISTURE IT WOULD NEED TO PRODUCE ANYTHING SIGNIFICANT. THE MAIN PLAYER WILL ROUND THE BASE OF THE TROUGH OVER THE SOUTHWESTERN U.S. SATURDAY. THERE ARE REALLY ONLY TWO LIKELY SCENARIOS THAT WILL PLAY OUT. THE FIRST ONE IS A PHASED SYSTEM WITH THE NORTHERN STREAM THAT RESULTS IN A ROBUST SURFACE CYCLONE WHICH TRACKS NORTH NORTHEAST FROM THE SOUTHERN PLAINS INTO THE WESTERN GREAT LAKES. THIS SCENARIO WOULD BRING A LOT OF MOISTURE WITH IT NORTHWARD...WITH A MATURE EXTRATROPICAL CYCLONE BY SUNDAY MORNING SOMEWHERE OVER THE UPPER MISSISSIPPI VALLEY. SUCH A TRACK IS A LIKELY HEAVY SNOW PRODUCER FOR US. THE OPERATIONAL GFS AND MANY OF ITS ENSEMBLES...THE CANADIAN...AND THE FORMER RUNS OF THE ECMWF INDICATED THIS AS A FAVORED OPTION. THE OTHER SCENARIO IS WHAT THE NEW ECMWF HAS REVERTED TO AND FEATURES THE UPPER LOW CLOSING OFF FROM THE NORTHERN STREAM WHICH RESULTS IN A LESS DEVELOPED...SLOW MOVING SOUTHERN CYCLONE AND LITTLE OR NO PRECIPITATION FOR US. AT THIS POINT EITHER SCENARIO IS POSSIBLE...BUT PREFER THE FIRST SOLUTION WHICH HAD STRONG SUPPORT OVERNIGHT. WILL AWAIT FOR FUTURE RUNS TO DETERMINE ANY MEANINGFUL TREND. FOLLOWING THE PASSAGE OF THAT SYSTEM IS ANOTHER ORIGINATING FROM THE NEXT TROUGH OVER THE WESTERN U.S. MODEL CONSISTENCY HAS NOT BEEN THE BEST WITH THIS ONE...LIKELY DUE TO ERRORS ASSOCIATED WITH ITS PREDECESSOR. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING) ISSUED AT 900 PM CST TUE DEC 8 2015 THE LIGHT RAIN IS SLOWLY MOVING OUT OF WESTERN WI AND THE BACK EDGE OF THE MID TO HIGH CLOUDS IS SLOWLY WORKING ACROSS MN FROM WEST TO EAST AT 20-30MPH. GIVEN THE RAIN AND LIGHT WIND...WE ARE SEEING A FEW POCKETS OF FOG IN EASTERN MN AND WESTERN WI. WE ARE A LITTLE CONCERNED THAT CLEARING COULD ALLOW THE FOG TO EXPAND LATE TONIGHT. WE ALSO EXPECT A SLIGHT INCREASE IN WIND...WHICH WOULD HELP INHIBIT FOG FORMATION. GIVEN THE UNCERTAINTY...WE`LL HAVE TO MONITOR THE VISIBILITY TRENDS AND UPDATE ACCORDINGLY. KMSP... WE INCLUDED A TEMPO FOR LIGHT FOG TONIGHT WITH MVFR VISIBILITY. THIS MIGHT NOT HAPPEN. THERE IS A LITTLE WIND OUT THERE AND THE AIRPORT IS TYPICALLY HARD TO FOG IN...BUT THE HUMIDITY IS CLOSE TO 100% THIS EVENING AND THE WIND HAS BEEN NEAR CALM AT TIMES...SO WHEN THE SKY CLEARS IT WOULD ONLY TAKE A SMALL AMOUNT OF COOLING TO START FORMING FOG. /OUTLOOK FOR KMSP/ THU...VFR WITH MVFR/-RA POSSIBLE. WIND W AT 10G20 KTS. FRI...VFR. WINDS ESE 5-10 KTS. SAT...VFR WITH MVFR POSSIBLE. WINDS NNW 5-10 KTS. && .MPX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. && $$ SHORT TERM...MPG LONG TERM...BORGHOFF AVIATION...CLF
AREA FORECAST DISCUSSION
NWS DULUTH MN
1154 AM CST MON DEC 7 2015 .UPDATE... ISSUED AT 1154 AM CST MON DEC 7 2015 UPDATED FOR 18Z AVIATION DISCUSSION BELOW && .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 342 AM CST MON DEC 7 2015 CLOUDS AND FOG THE MAIN CONCERN THIS MORNING...WITH A LARGE AREA OF STRATUS AND FOG OVER THE SOUTHERN HALF TO THIRD OF THE FORECAST AREA. THE LARGER SCALE MODELS ARE MISSING OUT ON A LOT OF THIS...BUT THE SHORT RANGE HI RES MODELS ARE PICKING UP ON IT...AND THE HRRR IS DOING A GOOD JOB WITH THE STRATUS AND FOG THIS MORNING SO FAR. A WEAK WARM FRONT IS DUE TO MOVE THROUGH THE AREA LATE THIS AFTERNOON AND TONIGHT. THE STRATUS WE HAVE NOW SHOULD BE SWEPT NORTHEAST ACROSS THE AREA THROUGH THE REMAINDER OF THE FORECAST AREA AHEAD OF THE FRONT...AND WHILE MIXING SHOULD HELP DISSIPATE THE FOG...THE STRATUS SHOULD REMAIN WITH SLIGHTLY HIGHER CEILINGS DURING THE DAY. THIS STRATUS TO KEEP TEMPERATURES DOWN AND HAVE PUT THE MAX TEMPERATURE IN THE MIDDLE 30S TO NEAR 40. TONIGHT AS THE WARM FRONT PASSES THROUGH THE CLOUD COVER SHOULD KEEP US WARMER THAN THIS MORNING AND EXPECT LOWS IN THE MID 20S TO NEAR 30...THOUGH THIS MAY BE TOO COLD AND WILL NOT BE SURPRISED IF WE NEED TO RAISE MORE. TUESDAY A WEAK SHORTWAVE WILL MOVE INTO THE AREA FROM THE NORTHWEST... AND MOVE INTO THE FORECAST AREA BY LATE AFTERNOON. THIS SHOULD BRING SOME CHANCES FOR RAIN TO MAINLY THE SOUTHERN HALF OF THE FORECAST AREA DURING THE AFTERNOON. FOR NOW IT APPEARS THAT THE PRECIPITATION SHOULD BE MAINLY RAIN...BUT WILL HAVE TO WATCH SURFACE TEMPS CLOSELY AS IT COULD BE MIXED WITH SNOW AT TIMES. .LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY) ISSUED AT 342 AM CST MON DEC 7 2015 RELATIVELY WARM WEATHER THROUGH THE REST OF THE WEEK...THEN FINALLY COOLING DOWN TO NEAR-SEASONABLE THIS WEEKEND. A FEW CHANCES FOR PRECIPITATION IN A FAIRLY ACTIVE PATTERN...LIGHT PRECIP TUESDAY NIGHT THEN MORE SUBSTANTIAL PRECIP AMOUNTS POSSIBLE LATE WED NIGHT INTO THURSDAY. ANOTHER CHANCE FOR LIGHT PRECIP AMOUNTS THROUGH THE WEEKEND...WITH A POSSIBLE SHOT AT LAKE EFFECT SNOW ALONG THE SOUTH SHORE LATE IN THE WEEKEND INTO EARLY NEXT WEEK. ALOFT 850MB TEMPS ARE WARM AT ABOUT 0 TO +5C THROUGH THE WEEK...THEN FALLING TO A MORE SEASONABLE -10 TO 0C THIS WEEKEND. /THOUGH THIS IS STILL A BIT ABOVE NORMAL...INL SOUNDING CLIMATOLOGY AVERAGES AROUND -10C FOR MID DECEMBER./ TUES NIGHT A WEAK STACKED LOW WILL MOVE SOUTHEAST ACROSS THE UPPER MIDWEST AS IT TRAVERSES FROM NORTHWEST MINNESOTA INTO NORTHERN WISCONSIN. THIS LOW WILL BE MAINLY EXITING THE REGION OVERNIGHT TUESDAY WITH NOT MUCH OF A SURFACE FRONT REFLECTED AT THE SFC. WHILE LOWS MAY REACH NEAR FREEZING AT THE SFC...ALOFT PROFILES WILL SUPPORT MAINLY LIGHT RAIN/DRIZZLE...WITH THE SUB-FREEZING TEMPS ARRIVING AT THE SFC WHEN MID/UPPER LEVELS DRY OUT TOWARDS WED MORNING. A LOW/MID LEVEL RIDGE BUILDS IN BEHIND THE LOW FOR WED RESULTING IN SOME CLEARING SKIES BUT NOT BEFORE HIGH CLOUDS BEGIN TO INCREASE LATE IN THE DAY AHEAD OF THE NEXT SYSTEM. LATE WED NIGHT INTO THURSDAY WILL BE THE BEST CHANCE FOR PRECIPITATION ACROSS THE REGION AS A MORE ORGANIZED SYSTEM MOVES ACROSS THE REGION. MID-LEVEL TROUGH EJECTING OUT OF THE GREAT BASIN INTO THE NORTHERN HIGH PLAINS WED NIGHT WILL RESULT IN A SFC TROUGH DEVELOPING IN RESPONSE ACROSS THE RED RIVER VALLEY...WITH A NORTHERN STREAM UPPER LOW RESULTING IN A SFC LOW ACROSS CENTRAL MANITOBA. TOWARDS THURSDAY THE BETTER LARGE-SCALE FORCING ARRIVES AS A POTENT UPPER LOW MOVES ACROSS THE NORTHERN PLAINS AND A SFC LOW DEEPENS ACROSS THE MN ARROWHEAD DURING THE DAY. SOUTHWESTERLY FLOW AHEAD OF THE LOW WED NIGHT INTO THURSDAY WILL RESULT IN ABUNDANT MOISTURE AT LOW/MID LEVELS...CAUSING PRECIPITABLE WATER VALUES TO REACH NEAR THREE QUARTERS OF AN INCH...NEAR RECORD-BREAKING FOR THIS TIME OF YEAR. THIS ABUNDANT MOISTURE COMBINED WITH THE WIDESPREAD LARGE- SCALE LIFT DRIVEN BY THE POTENT UPPER LOW AND WARM AIR ADVECTION AHEAD OF THE LOW WILL RESULT IN WIDESPREAD PRECIPITATION...MAINLY IN THE FORM OF RAIN DURING THE DAY THURSDAY....BUT CHANGING TO SNOW THURSDAY NIGHT AS THE DEEPENING LOW DRAWS IN COLDER AIR FROM THE NORTHWEST. BY FRIDAY MORNING THE LOW BECOMES STACKED OVER NORTHERN LAKE SUPERIOR RESULTING IN NORTH TO NORTHWESTERLY FLOW ACROSS THE NORTHLAND...BRINGING A CHANCE FOR ACCUMULATING SNOWFALL INTO FRIDAY MORNING BEFORE THE LOW LIFTS OFF THE NORTHWEST. THE COLD AIR THIS SYSTEM WILL DRAW IN IS STILL VERY WARM...850MB TEMPS BARELY DIPPING BELOW -5C...SO LAKE EFFECT POTENTIAL LOOKS TO BE LIMITED. WHILE THE RAIN/SNOW OCCURS ON THURSDAY INTO FRIDAY MORNING THERE WILL BE A DEEP LONGWAVE TROUGH DEVELOPING ACROSS THE WESTERN HALF OF THE LOWER 48...A SIGNIFICANT CHANGE IN THE SYNOPTIC-SCALE PATTERN. THIS TROUGH WILL DIG DEEPER THAN EARLIER EVENTS THIS LATE FALL/EARLY WINTER...WITH GUIDANCE LEANING TOWARDS A SLOWER PROGRESSION WHICH WOULD CAUSE THE STORM TRACK TO BE ALIGNED TOO FAR EAST TO BRING ANY SIGNIFICANT STORMS ASSOCIATED WITH THIS TROUGH AT LEAST THROUGH THE WEEKEND. HOWEVER...AS THE LONGWAVE TROUGH DEVELOPS FRIDAY A MID- LEVEL IMPULSE MOVING ACROSS THE SOUTHWESTERLY FLOW DEVELOPING COULD RESULT IN A SFC LOW OVER THE UPPER MISSISSIPPI VALLEY FRIDAY INTO FRIDAY NIGHT...WHICH COULD PULL IN ANOTHER SHOT AT COLDER AIR FROM CANADA IN ADDITION TO THE CHANCE FOR PRECIPITATION. CONFIDENCE IS NOT AS HIGH REGARDS TO TIMING...BUT THIS SET UP WOULD SEEM TO FAVOR LIGHT PRECIP CHANCES INTO THE WEEKEND AS COLDER NORTHWESTERLY FLOW DEVELOPS IN WAKE OF THIS SFC LOW. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1154 AM CST MON DEC 7 2015 MVFR CIGS WILL LIKELY CONTINUE ALONG THE NORTH SHORE OF LATE SUPERIOR THIS AFTERNOON.... WITH VFR/MVFR CIGS/VIS CONTINUING ON AND OFF AS A SFC FRONT PASSES THROUGH THE NORTHLAND THIS EVENING. THE FROPA WILL DROP CONDITIONS BACK DOWN TO MVFR/IFR TONIGHT WITH OCCASIONAL LIFR FOG EXPECTED... ESPECIALLY AT KDLH. EXPECT GUSTY WINDS OUT OF THE SOUTH UP TO 20KTS TO CONTINUE THIS AFTERNOON BECOMING LIGHT OVERNIGHT. A GRADUAL IMPROVEMENT TO MVFR/VFR WILL COME AFTER 18Z TUESDAY. && .PRELIMINARY POINT TEMPS/POPS... DLH 39 29 41 30 / 0 0 20 30 INL 40 27 41 26 / 0 0 10 20 BRD 40 27 41 29 / 0 0 30 30 HYR 41 27 42 30 / 10 10 20 40 ASX 43 31 44 31 / 0 10 10 30 && .DLH WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. LS...SMALL CRAFT ADVISORY FROM 10 PM THIS EVENING TO 4 AM CST TUESDAY FOR LSZ140. && $$ SHORT TERM...LE LONG TERM...JJM AVIATION...MCLOVIN
AREA FORECAST DISCUSSION
NWS DULUTH MN
527 AM CST MON DEC 7 2015 .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 342 AM CST MON DEC 7 2015 CLOUDS AND FOG THE MAIN CONCERN THIS MORNING...WITH A LARGE AREA OF STRATUS AND FOG OVER THE SOUTHERN HALF TO THIRD OF THE FORECAST AREA. THE LARGER SCALE MODELS ARE MISSING OUT ON A LOT OF THIS...BUT THE SHORT RANGE HI RES MODELS ARE PICKING UP ON IT...AND THE HRRR IS DOING A GOOD JOB WITH THE STRATUS AND FOG THIS MORNING SO FAR. A WEAK WARM FRONT IS DUE TO MOVE THROUGH THE AREA LATE THIS AFTERNOON AND TONIGHT. THE STRATUS WE HAVE NOW SHOULD BE SWEPT NORTHEAST ACROSS THE AREA THROUGH THE REMAINDER OF THE FORECAST AREA AHEAD OF THE FRONT...AND WHILE MIXING SHOULD HELP DISSIPATE THE FOG...THE STRATUS SHOULD REMAIN WITH SLIGHTLY HIGHER CEILINGS DURING THE DAY. THIS STRATUS TO KEEP TEMPERATURES DOWN AND HAVE PUT THE MAX TEMPERATURE IN THE MIDDLE 30S TO NEAR 40. TONIGHT AS THE WARM FRONT PASSES THROUGH THE CLOUD COVER SHOULD KEEP US WARMER THAN THIS MORNING AND EXPECT LOWS IN THE MID 20S TO NEAR 30...THOUGH THIS MAY BE TOO COLD AND WILL NOT BE SURPRISED IF WE NEED TO RAISE MORE. TUESDAY A WEAK SHORTWAVE WILL MOVE INTO THE AREA FROM THE NORTHWEST... AND MOVE INTO THE FORECAST AREA BY LATE AFTERNOON. THIS SHOULD BRING SOME CHANCES FOR RAIN TO MAINLY THE SOUTHERN HALF OF THE FORECAST AREA DURING THE AFTERNOON. FOR NOW IT APPEARS THAT THE PRECIPITATION SHOULD BE MAINLY RAIN...BUT WILL HAVE TO WATCH SURFACE TEMPS CLOSELY AS IT COULD BE MIXED WITH SNOW AT TIMES. .LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY) ISSUED AT 342 AM CST MON DEC 7 2015 RELATIVELY WARM WEATHER THROUGH THE REST OF THE WEEK...THEN FINALLY COOLING DOWN TO NEAR-SEASONABLE THIS WEEKEND. A FEW CHANCES FOR PRECIPITATION IN A FAIRLY ACTIVE PATTERN...LIGHT PRECIP TUESDAY NIGHT THEN MORE SUBSTANTIAL PRECIP AMOUNTS POSSIBLE LATE WED NIGHT INTO THURSDAY. ANOTHER CHANCE FOR LIGHT PRECIP AMOUNTS THROUGH THE WEEKEND...WITH A POSSIBLE SHOT AT LAKE EFFECT SNOW ALONG THE SOUTH SHORE LATE IN THE WEEKEND INTO EARLY NEXT WEEK. ALOFT 850MB TEMPS ARE WARM AT ABOUT 0 TO +5C THROUGH THE WEEK...THEN FALLING TO A MORE SEASONABLE -10 TO 0C THIS WEEKEND. /THOUGH THIS IS STILL A BIT ABOVE NORMAL...INL SOUNDING CLIMATOLOGY AVERAGES AROUND -10C FOR MID DECEMBER./ TUES NIGHT A WEAK STACKED LOW WILL MOVE SOUTHEAST ACROSS THE UPPER MIDWEST AS IT TRAVERSES FROM NORTHWEST MINNESOTA INTO NORTHERN WISCONSIN. THIS LOW WILL BE MAINLY EXITING THE REGION OVERNIGHT TUESDAY WITH NOT MUCH OF A SURFACE FRONT REFLECTED AT THE SFC. WHILE LOWS MAY REACH NEAR FREEZING AT THE SFC...ALOFT PROFILES WILL SUPPORT MAINLY LIGHT RAIN/DRIZZLE...WITH THE SUB-FREEZING TEMPS ARRIVING AT THE SFC WHEN MID/UPPER LEVELS DRY OUT TOWARDS WED MORNING. A LOW/MID LEVEL RIDGE BUILDS IN BEHIND THE LOW FOR WED RESULTING IN SOME CLEARING SKIES BUT NOT BEFORE HIGH CLOUDS BEGIN TO INCREASE LATE IN THE DAY AHEAD OF THE NEXT SYSTEM. LATE WED NIGHT INTO THURSDAY WILL BE THE BEST CHANCE FOR PRECIPITATION ACROSS THE REGION AS A MORE ORGANIZED SYSTEM MOVES ACROSS THE REGION. MID-LEVEL TROUGH EJECTING OUT OF THE GREAT BASIN INTO THE NORTHERN HIGH PLAINS WED NIGHT WILL RESULT IN A SFC TROUGH DEVELOPING IN RESPONSE ACROSS THE RED RIVER VALLEY...WITH A NORTHERN STREAM UPPER LOW RESULTING IN A SFC LOW ACROSS CENTRAL MANITOBA. TOWARDS THURSDAY THE BETTER LARGE-SCALE FORCING ARRIVES AS A POTENT UPPER LOW MOVES ACROSS THE NORTHERN PLAINS AND A SFC LOW DEEPENS ACROSS THE MN ARROWHEAD DURING THE DAY. SOUTHWESTERLY FLOW AHEAD OF THE LOW WED NIGHT INTO THURSDAY WILL RESULT IN ABUNDANT MOISTURE AT LOW/MID LEVELS...CAUSING PRECIPITABLE WATER VALUES TO REACH NEAR THREE QUARTERS OF AN INCH...NEAR RECORD-BREAKING FOR THIS TIME OF YEAR. THIS ABUNDANT MOISTURE COMBINED WITH THE WIDESPREAD LARGE- SCALE LIFT DRIVEN BY THE POTENT UPPER LOW AND WARM AIR ADVECTION AHEAD OF THE LOW WILL RESULT IN WIDESPREAD PRECIPITATION...MAINLY IN THE FORM OF RAIN DURING THE DAY THURSDAY....BUT CHANGING TO SNOW THURSDAY NIGHT AS THE DEEPENING LOW DRAWS IN COLDER AIR FROM THE NORTHWEST. BY FRIDAY MORNING THE LOW BECOMES STACKED OVER NORTHERN LAKE SUPERIOR RESULTING IN NORTH TO NORTHWESTERLY FLOW ACROSS THE NORTHLAND...BRINGING A CHANCE FOR ACCUMULATING SNOWFALL INTO FRIDAY MORNING BEFORE THE LOW LIFTS OFF THE NORTHWEST. THE COLD AIR THIS SYSTEM WILL DRAW IN IS STILL VERY WARM...850MB TEMPS BARELY DIPPING BELOW -5C...SO LAKE EFFECT POTENTIAL LOOKS TO BE LIMITED. WHILE THE RAIN/SNOW OCCURS ON THURSDAY INTO FRIDAY MORNING THERE WILL BE A DEEP LONGWAVE TROUGH DEVELOPING ACROSS THE WESTERN HALF OF THE LOWER 48...A SIGNIFICANT CHANGE IN THE SYNOPTIC-SCALE PATTERN. THIS TROUGH WILL DIG DEEPER THAN EARLIER EVENTS THIS LATE FALL/EARLY WINTER...WITH GUIDANCE LEANING TOWARDS A SLOWER PROGRESSION WHICH WOULD CAUSE THE STORM TRACK TO BE ALIGNED TOO FAR EAST TO BRING ANY SIGNIFICANT STORMS ASSOCIATED WITH THIS TROUGH AT LEAST THROUGH THE WEEKEND. HOWEVER...AS THE LONGWAVE TROUGH DEVELOPS FRIDAY A MID- LEVEL IMPULSE MOVING ACROSS THE SOUTHWESTERLY FLOW DEVELOPING COULD RESULT IN A SFC LOW OVER THE UPPER MISSISSIPPI VALLEY FRIDAY INTO FRIDAY NIGHT...WHICH COULD PULL IN ANOTHER SHOT AT COLDER AIR FROM CANADA IN ADDITION TO THE CHANCE FOR PRECIPITATION. CONFIDENCE IS NOT AS HIGH REGARDS TO TIMING...BUT THIS SET UP WOULD SEEM TO FAVOR LIGHT PRECIP CHANCES INTO THE WEEKEND AS COLDER NORTHWESTERLY FLOW DEVELOPS IN WAKE OF THIS SFC LOW. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 527 AM CST MON DEC 7 2015 MAINLY IFR CONDITIONS THROUGH THE TAF PERIOD AT MOST TAF SITES...WITH A PERIOD OF IMPROVEMENT LATE THIS MORNING INTO THE EARLY AFTERNOON BEFORE CONDITIONS DETERIORATE AGAIN TONIGHT. LIFR/VLIFR FOG AND STRATUS ACROSS THE REGION THIS MORNING IS GRADUALLY WANING AS MID/HIGH LEVEL CLOUDS MOVE ACROSS NORTHERN MINNESOTA THIS MORNING...CAUSING CEILINGS AND VISIBILITIES TO IMPROVE. THIS TREND WILL CONTINUE FROM WEST TO EAST...WITH A STRONG LOW LEVEL JET DEVELOPING ACROSS NORTHERN MINNESOTA BY MID MORNING...CAUSING LOW LEVEL WIND SHEAR AT BRD...HIB...AND INL..PEAKING AROUND 15Z WITH 40KT WINDS AROUND 1500-2000 FEET ABOVE THE GROUND. WILL LIKELY SEE CONDITIONS TRANSITION TO MVFR OR VFR EVERYWHERE FOR A TIME THIS AFTERNOON BEFORE FOG/STRATUS REDEVELOPS TONIGHT AND SPREADS ACROSS THE REGION RESULTING IN IFR OR WORSE CONDITIONS. WINDS LIGHT OUT OF THE SOUTH TO SOUTHEAST THIS MORNING...PICKING UP FOR A TIME MID MORNING INTO THE EARLY AFTERNOON OUT OF THE SOUTH TO SOUTHWEST WITH PEAK GUSTS TO AROUND 20 KNOTS...THEN RETURNING TO LIGHT WINDS THIS EVENING. && .PRELIMINARY POINT TEMPS/POPS... DLH 37 29 41 30 / 0 0 20 30 INL 39 27 41 26 / 0 0 10 20 BRD 39 27 41 29 / 0 0 30 30 HYR 40 27 42 30 / 10 10 20 40 ASX 42 31 44 31 / 0 10 10 30 && .DLH WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...DENSE FOG ADVISORY UNTIL 8 AM CST THIS MORNING FOR MNZ034>038. DENSE FOG ADVISORY UNTIL 6 AM CST EARLY THIS MORNING FOR MNZ025- 026-033. LS...SMALL CRAFT ADVISORY FROM 10 PM THIS EVENING TO 4 AM CST TUESDAY FOR LSZ140. && $$ SHORT TERM...LE LONG TERM...JJM AVIATION...JJM
AREA FORECAST DISCUSSION
NWS DULUTH MN
349 AM CST MON DEC 7 2015 .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 342 AM CST MON DEC 7 2015 CLOUDS AND FOG THE MAIN CONCERN THIS MORNING...WITH A LARGE AREA OF STRATUS AND FOG OVER THE SOUTHERN HALF TO THIRD OF THE FORECAST AREA. THE LARGER SCALE MODELS ARE MISSING OUT ON A LOT OF THIS...BUT THE SHORT RANGE HI RES MODELS ARE PICKING UP ON IT...AND THE HRRR IS DOING A GOOD JOB WITH THE STRATUS AND FOG THIS MORNING SO FAR. A WEAK WARM FRONT IS DUE TO MOVE THROUGH THE AREA LATE THIS AFTERNOON AND TONIGHT. THE STRATUS WE HAVE NOW SHOULD BE SWEPT NORTHEAST ACROSS THE AREA THROUGH THE REMAINDER OF THE FORECAST AREA AHEAD OF THE FRONT...AND WHILE MIXING SHOULD HELP DISSIPATE THE FOG...THE STRATUS SHOULD REMAIN WITH SLIGHTLY HIGHER CEILINGS DURING THE DAY. THIS STRATUS TO KEEP TEMPERATURES DOWN AND HAVE PUT THE MAX TEMPERATURE IN THE MIDDLE 30S TO NEAR 40. TONIGHT AS THE WARM FRONT PASSES THROUGH THE CLOUD COVER SHOULD KEEP US WARMER THAN THIS MORNING AND EXPECT LOWS IN THE MID 20S TO NEAR 30...THOUGH THIS MAY BE TOO COLD AND WILL NOT BE SURPRISED IF WE NEED TO RAISE MORE. TUESDAY A WEAK SHORTWAVE WILL MOVE INTO THE AREA FROM THE NORTHWEST... AND MOVE INTO THE FORECAST AREA BY LATE AFTERNOON. THIS SHOULD BRING SOME CHANCES FOR RAIN TO MAINLY THE SOUTHERN HALF OF THE FORECAST AREA DURING THE AFTERNOON. FOR NOW IT APPEARS THAT THE PRECIPITATION SHOULD BE MAINLY RAIN...BUT WILL HAVE TO WATCH SURFACE TEMPS CLOSELY AS IT COULD BE MIXED WITH SNOW AT TIMES. .LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY) ISSUED AT 342 AM CST MON DEC 7 2015 RELATIVELY WARM WEATHER THROUGH THE REST OF THE WEEK...THEN FINALLY COOLING DOWN TO NEAR-SEASONABLE THIS WEEKEND. A FEW CHANCES FOR PRECIPITATION IN A FAIRLY ACTIVE PATTERN...LIGHT PRECIP TUESDAY NIGHT THEN MORE SUBSTANTIAL PRECIP AMOUNTS POSSIBLE LATE WED NIGHT INTO THURSDAY. ANOTHER CHANCE FOR LIGHT PRECIP AMOUNTS THROUGH THE WEEKEND...WITH A POSSIBLE SHOT AT LAKE EFFECT SNOW ALONG THE SOUTH SHORE LATE IN THE WEEKEND INTO EARLY NEXT WEEK. ALOFT 850MB TEMPS ARE WARM AT ABOUT 0 TO +5C THROUGH THE WEEK...THEN FALLING TO A MORE SEASONABLE -10 TO 0C THIS WEEKEND. /THOUGH THIS IS STILL A BIT ABOVE NORMAL...INL SOUNDING CLIMATOLOGY AVERAGES AROUND -10C FOR MID DECEMBER./ TUES NIGHT A WEAK STACKED LOW WILL MOVE SOUTHEAST ACROSS THE UPPER MIDWEST AS IT TRAVERSES FROM NORTHWEST MINNESOTA INTO NORTHERN WISCONSIN. THIS LOW WILL BE MAINLY EXITING THE REGION OVERNIGHT TUESDAY WITH NOT MUCH OF A SURFACE FRONT REFLECTED AT THE SFC. WHILE LOWS MAY REACH NEAR FREEZING AT THE SFC...ALOFT PROFILES WILL SUPPORT MAINLY LIGHT RAIN/DRIZZLE...WITH THE SUB-FREEZING TEMPS ARRIVING AT THE SFC WHEN MID/UPPER LEVELS DRY OUT TOWARDS WED MORNING. A LOW/MID LEVEL RIDGE BUILDS IN BEHIND THE LOW FOR WED RESULTING IN SOME CLEARING SKIES BUT NOT BEFORE HIGH CLOUDS BEGIN TO INCREASE LATE IN THE DAY AHEAD OF THE NEXT SYSTEM. LATE WED NIGHT INTO THURSDAY WILL BE THE BEST CHANCE FOR PRECIPITATION ACROSS THE REGION AS A MORE ORGANIZED SYSTEM MOVES ACROSS THE REGION. MID-LEVEL TROUGH EJECTING OUT OF THE GREAT BASIN INTO THE NORTHERN HIGH PLAINS WED NIGHT WILL RESULT IN A SFC TROUGH DEVELOPING IN RESPONSE ACROSS THE RED RIVER VALLEY...WITH A NORTHERN STREAM UPPER LOW RESULTING IN A SFC LOW ACROSS CENTRAL MANITOBA. TOWARDS THURSDAY THE BETTER LARGE-SCALE FORCING ARRIVES AS A POTENT UPPER LOW MOVES ACROSS THE NORTHERN PLAINS AND A SFC LOW DEEPENS ACROSS THE MN ARROWHEAD DURING THE DAY. SOUTHWESTERLY FLOW AHEAD OF THE LOW WED NIGHT INTO THURSDAY WILL RESULT IN ABUNDANT MOISTURE AT LOW/MID LEVELS...CAUSING PRECIPITABLE WATER VALUES TO REACH NEAR THREE QUARTERS OF AN INCH...NEAR RECORD-BREAKING FOR THIS TIME OF YEAR. THIS ABUNDANT MOISTURE COMBINED WITH THE WIDESPREAD LARGE- SCALE LIFT DRIVEN BY THE POTENT UPPER LOW AND WARM AIR ADVECTION AHEAD OF THE LOW WILL RESULT IN WIDESPREAD PRECIPITATION...MAINLY IN THE FORM OF RAIN DURING THE DAY THURSDAY....BUT CHANGING TO SNOW THURSDAY NIGHT AS THE DEEPENING LOW DRAWS IN COLDER AIR FROM THE NORTHWEST. BY FRIDAY MORNING THE LOW BECOMES STACKED OVER NORTHERN LAKE SUPERIOR RESULTING IN NORTH TO NORTHWESTERLY FLOW ACROSS THE NORTHLAND...BRINGING A CHANCE FOR ACCUMULATING SNOWFALL INTO FRIDAY MORNING BEFORE THE LOW LIFTS OFF THE NORTHWEST. THE COLD AIR THIS SYSTEM WILL DRAW IN IS STILL VERY WARM...850MB TEMPS BARELY DIPPING BELOW -5C...SO LAKE EFFECT POTENTIAL LOOKS TO BE LIMITED. WHILE THE RAIN/SNOW OCCURS ON THURSDAY INTO FRIDAY MORNING THERE WILL BE A DEEP LONGWAVE TROUGH DEVELOPING ACROSS THE WESTERN HALF OF THE LOWER 48...A SIGNIFICANT CHANGE IN THE SYNOPTIC-SCALE PATTERN. THIS TROUGH WILL DIG DEEPER THAN EARLIER EVENTS THIS LATE FALL/EARLY WINTER...WITH GUIDANCE LEANING TOWARDS A SLOWER PROGRESSION WHICH WOULD CAUSE THE STORM TRACK TO BE ALIGNED TOO FAR EAST TO BRING ANY SIGNIFICANT STORMS ASSOCIATED WITH THIS TROUGH AT LEAST THROUGH THE WEEKEND. HOWEVER...AS THE LONGWAVE TROUGH DEVELOPS FRIDAY A MID- LEVEL IMPULSE MOVING ACROSS THE SOUTHWESTERLY FLOW DEVELOPING COULD RESULT IN A SFC LOW OVER THE UPPER MISSISSIPPI VALLEY FRIDAY INTO FRIDAY NIGHT...WHICH COULD PULL IN ANOTHER SHOT AT COLDER AIR FROM CANADA IN ADDITION TO THE CHANCE FOR PRECIPITATION. CONFIDENCE IS NOT AS HIGH REGARDS TO TIMING...BUT THIS SET UP WOULD SEEM TO FAVOR LIGHT PRECIP CHANCES INTO THE WEEKEND AS COLDER NORTHWESTERLY FLOW DEVELOPS IN WAKE OF THIS SFC LOW. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1145 PM CST SUN DEC 6 2015 LIFR/VLIFR WITH BR/FZFG HAS SPREAD TO ALL TERMINALS BUT INL AT THE OUTSET OF THE FORECAST. LOW CLOUDS WERE MOVING NWD TOWARD INL...BUT CONFIDENCE WAS LOW ON ADDING ATTM. LATEST HRRR AND RAP CONTINUE TO INDICATE THE BR/FZFG WILL BEGIN TO LIFT FROM WEST TO EAST BEGINNING AT 12Z NEAR BRD AND REACHING HYR BY 17Z. VFR IS THEN EXPECTED UNTIL THE NEXT BATCH OF LOW CLOUDS AND BR ARRIVES AFTER 18Z WITH MVFR CONDITIONS. && .PRELIMINARY POINT TEMPS/POPS... DLH 40 29 42 30 / 0 0 20 20 INL 42 28 42 27 / 0 0 30 20 BRD 42 28 43 27 / 0 0 30 20 HYR 43 29 43 30 / 0 10 20 20 ASX 45 32 45 31 / 0 10 20 20 && .DLH WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...DENSE FOG ADVISORY UNTIL 8 AM CST THIS MORNING FOR MNZ034>038. DENSE FOG ADVISORY UNTIL 6 AM CST EARLY THIS MORNING FOR MNZ025- 026-033. LS...SMALL CRAFT ADVISORY FROM 10 PM THIS EVENING TO 4 AM CST TUESDAY FOR LSZ140. && $$ SHORT TERM...LE LONG TERM...JJM AVIATION...GSF
AREA FORECAST DISCUSSION
NWS DULUTH MN
1145 PM CST SUN DEC 6 2015 .UPDATE... ISSUED AT 944 PM CST SUN DEC 6 2015 DENSE FOG HAS BEEN FORMING/EXPANDING AND PERSISTING FROM CASS AND SOUTHERN ITASCA EASTWARD TO SOUTHERN ST. LOUIS...CARLTON AND PINE COUNTIES. EXPIRATION TIMES ARE BASED ON THE LAST FEW RUNS OF THE HRRR EXP AND RAP WHICH HAVE BEEN VERY CONSISTENT. REST OF THE FORECAST IN GOOD SHAPE. && .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 246 PM CST SUN DEC 6 2015 STRATUS AND FOG HAS SLOWLY ERODED FROM THE NORTH AND AND WEST TODAY. STRATUS REMAINED OVER OUR SOUTHERN WISCONSIN COUNTIES AND ACROSS PORTIONS OF CROW WING...AITKIN...PINE AND CARLTON COUNTIES IN MINNESOTA AS OF LATE AFTERNOON. THE DIMINISHING TREND SHOULD CONTINUE FOR A COUPLE MORE HOURS...THEN IT MAY EXPAND AGAIN AFTER SUNSET. WEAK HIGH PRESSURE WILL MOVE THROUGH THE AREA TONIGHT WITH LIGHT WINDS THIS EVENING. FOG SHOULD ALSO FORM THROUGH THE EVENING. THE GRADIENT WILL TIGHTEN OVERNIGHT...MAINLY OVER WESTERN AREAS. AS THIS OCCURS OVERNIGHT...THE FOG MAY LIFT AND ANY STRATUS MAY START TO DISSIPATE AS SOME MIXING WITH THE VERY DRY AIR ALOFT OCCURS. THIS IS MOST LIKELY OVER THE WESTERN HALF OF THE NORTHLAND. A SHORTWAVE WILL MOVE IN ON MONDAY AS THE HIGH DEPARTS. AT THIS TIME...WE HAVE A DRY FORECAST AS MOISTURE IS LACKING AND THE FORCING IS NOT VERY STRONG. WE DO EXPECT MOSTLY CLOUDY SKIES THROUGH THE DAY. IT WILL BE MILD WITH HIGHS IN THE UPPER THIRTIES TO LOWER FORTIES. ANOTHER SHORTWAVE WILL IMPACT THE REGION ON TUESDAY AND BRING A CHANCE FOR PRECIPITATION. AT THIS TIME...IT LOOKS LIKE MAINLY RAIN WILL FALL DURING THE DAY. HIGHS WILL BE IN THE LOWER FORTIES. .LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY) ISSUED AT 246 PM CST SUN DEC 6 2015 CONTINUED ABOVE NORMAL TEMPERATURES THROUGH MOST OF THE EXTENDED. HAVE KEPT SMALL POPS FOR RA/SN MIX TUESDAY NIGHT AS AN 850HPA LOW SWEEPS OVER THE REGION. DEPENDING ON THE TIMING OF THE WAVE/PRECIPITATION...THERE COULD BE A PERIOD OF LIGHT FREEZING DRIZZLE/RAIN. HOWEVER...PRECIPITATION AMOUNTS LOOK TO REMAIN LIGHT WITH THIS FAST MOVING SYSTEM. LONG RANGE MODELS SHOWING A STRENGTHENING LOW PRESSURE SYSTEM WITH DEEPENING 500HPA LOW...TRACKS ACROSS THE UPPER MIDWEST/WESTERN GREAT LAKES REGION WEDNESDAY NIGHT/THURSDAY. LATEST GFS AND EC ARE IN AGREEMENT STRONG WARM AIR ADVECTION ACCOMPANIES THIS SYSTEM...BRINGING 850HPA WELL ABOVE 0C INTO THE REGION AHEAD OF THE LOW AND KEEPING PTYPE ALL RAIN. TEMPERATURE PROFILES RAPIDLY COOL LATE THURSDAY/THURSDAY NIGHT AS THE SYSTEM RETREATS OVER THE GREAT LAKES AND WINDS TURN OUT OF THE WEST/NORTHWEST. ALTHOUGH TIMING AND TRACK OF THE LOW VARIES...BOTH MODELS ARE SHOWING THE BULK OF THE FORCING/PRECIPITATION IS ASSOCIATED WITH THE DEEPENING 850HPA LOW ALIGNED WITH A 500HPA VORT MAX...WHICH BRINGS CORRIDOR OF QPF IN EXCESS OF 0.5 INCH AND THE POTENTIAL FOR A FEW INCHES OF SNOWFALL ACROSS NORTHERN MINNESOTA. THERE MAY BE A PERIOD FAVORABLE FOR LAKE EFFECT SNOW ALONG THE SOUTH SHORE OF LAKE SUPERIOR SUNDAY NIGHT/MONDAY AS AN AREA OF 850HPA TEMPS IN THE NEGATIVE TEENS SPREADS OVER LAKE SUPERIOR. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1145 PM CST SUN DEC 6 2015 LIFR/VLIFR WITH BR/FZFG HAS SPREAD TO ALL TERMINALS BUT INL AT THE OUTSET OF THE FORECAST. LOW CLOUDS WERE MOVING NWD TOWARD INL...BUT CONFIDENCE WAS LOW ON ADDING ATTM. LATEST HRRR AND RAP CONTINUE TO INDICATE THE BR/FZFG WILL BEGIN TO LIFT FROM WEST TO EAST BEGINNING AT 12Z NEAR BRD AND REACHING HYR BY 17Z. VFR IS THEN EXPECTED UNTIL THE NEXT BATCH OF LOW CLOUDS AND BR ARRIVES AFTER 18Z WITH MVFR CONDITIONS. && .PRELIMINARY POINT TEMPS/POPS... DLH 25 40 29 42 / 0 0 0 20 INL 22 42 28 42 / 0 0 0 30 BRD 24 42 28 43 / 0 0 0 30 HYR 22 43 29 43 / 0 0 10 20 ASX 23 45 32 45 / 0 0 10 20 && .DLH WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...DENSE FOG ADVISORY UNTIL 8 AM CST MONDAY FOR MNZ034>038. DENSE FOG ADVISORY UNTIL 6 AM CST MONDAY FOR MNZ025-026-033. LS...NONE. && $$ UPDATE...GSF SHORT TERM...MELDE LONG TERM...GRANING AVIATION...GSF
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1100 PM CST SUN DEC 6 2015 .UPDATED FOR 06Z AVIATION DISCUSSION... ISSUED AT 1052 PM CST SUN DEC 6 2015 && .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 400 PM CST SUN DEC 6 2015 THE MAIN CONCERN IN THE SHORT TERM IS THE THREAT OF WIDESPREAD DENSE FOG ACROSS MUCH OF THE FA TONIGHT. AT MID AFTERNOON...A SURFACE HIGH WAS LOCATED NEAR KSTC. A FEW POCKETS OF DENSE FOG REMAINED UNDER THE RIDGE AXIS AROUND KLJF...KOVL...KULM. CLEARING EXISTS JUST WEST OF THESE SITES. THE CONCERN IS THAT THE POCKETS OF DENSE FOG WILL CONGEAL AND BEGIN TO SPREAD NW THIS EVENING AS LIGHT SE WINDS DEVELOP ON THE BACKSIDE OF THE HIGH. THE WORST CASE SCENARIO CONTINUES TO BE FROM THE HRRR WITH WIDESPREAD DENSE FOG SPREADING IN ALL DIRECTIONS THIS EVENING. THIS HAS BEEN A TREND SEEN SINCE EARLY THIS MORNING. THE 18Z HOPWRF HAS A SIMILAR SOLUTION EXCEPT IT DIMINISHES THE FOG IN THE WESTERN CWA LATE TONIGHT. THE 12Z ARW KEEPS THE DENSE FOG MORE CONFINED TO WHERE IT IS THROUGH THE EVENING AND THEN BEGINS TO DIMINISH IT DURING THE OVERNIGHT HOURS AS THE SURFACE WIND FIELD BEGINS TO INCREASE FROM THE SE. MODELED THE FORECAST MORE TOWARDS THE ARW DUE TO THE INCREASE IN WINDS TO THE WEST ALONG WITH THE FACT THAT EASTERN MN AND WESTERN WI ARE ALREADY COVERED IN MVFR/IFR CEILINGS WITH LITTLE RADIATIONAL COMPONENT SEEN AS WELL AS THE ADVECTIVE COMPONENT HAVING COME TO AN END. THEREFORE...MENTIONED DENSE FOG FOR THE AFOREMENTIONED AREA OF CENTRAL/SOUTH CENTRAL MN THROUGH THE EVENING WITH VISIBILITIES PICKING UP OVERNIGHT. OTHERWISE...DRY WEATHER THROUGH THE SHORT TERM PERIOD. LOWS TONIGHT ARE FORECAST TO BE IN THE MIDDLE TO UPPER 20S. THE COLDEST READINGS ARE FROM MILLE LACS ON EASTWARD WHERE SOME CLEARING MAY REACH IN FROM THE NORTH LATE TONIGHT. THERE IS PLENTY OF POTENTIAL FOR WARM HIGHS ON MONDAY. HOWEVER...MUCH DEPENDS ON THE CLOUD COVER AND THE HEIGHT OF THE MIXING. KEEPING THE MIXING TO 950 MB YIELDS HIGHS IN THE LOWER TO MIDDLE 40S. AN EXCEPTION IS NEAR KCNB WHERE DOWNSLOPE WINDS MAY YIELD HIGHS AGAIN IN THE LOWER 50S. RAISING THE MIXING HEIGHT TO 925 MB INCREASES HIGH TEMPERATURES SOME 5 TO 8 DEGREES CWA WIDE. OPTED TO STAY WITH THE LOWER MIXING HEIGHT DUE TO THE CLOUD COVER UNCERTAINTY ALONG WITH THE SNOW COVER OVER THE WESTERN THIRD OF THE FA. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 400 PM CST SUN DEC 6 2015 STEADY MILD TEMPERATURES WITH A FEW CHANCES FOR LIGHT/QUICK SHOTS OF PRECIP ARE THE STORY FOR THE UPCOMING WEEK. AT THIS POINT...THE DOMINATE PRECIP TYPE IS RAIN. I COUNT 6-8 SHORTWAVES QUICKLY RIPPLING ACROSS THE NORTHERN CONUS OVER THE NEXT WEEK. MOST OF THESE WILL HAVE NO MAJOR IMPACTS ON OUR SENSIBLE WEATHER. THE TWO MORE AMPLIFIED WAVES /ON TUES AND THURS/ WILL LIKELY BRING LIGHT PRECIP TO OR NEAR THE AREA. THE FIRST SHORTWAVE MOVES THROUGH ON TUESDAY AND WE HAVE INCREASED POPS TO FROM 0-10% TO 20-40% DURING THE AFTERNOON AND EVENING. THE LIMITING FACTOR WITH THIS SYSTEM IS THE ABUNDANCE OF MOISTURE AND A FAIRLY DRY LOWER ATMOSPHERE BELOW 8000-10000FT. THIS SUGGESTS A LIGHT QPF EVENT WITH SOME CONCERN IN THE OVERALL PRECIP COVERAGE. THE FORECAST SOUNDINGS DEPICT A RAIN OR RAIN/SLEET MIX EVEN IF WE MAXIMIZE OUR WET BULB COOLING...IT SIMPLY LOOKS TOO WARM FOR SNOW AS THE DOMINANT PRECIP TYPE ON TUESDAY. THE SHORTWAVE SWINGS THROUGH QUICKLY AND THE PRECIP SHOULD SHUT OFF QUICKLY TUESDAY NIGHT. LIKE MOST COLD FRONTS THE PAST 3 MONTHS...THE COLD ADVECTION IS WEAK AND THERE WONT BE MUCH OF A TEMPERATURE REFLECTION. WEDNESDAY LOOKS QUIET AND MILD AT THIS POINT...BEFORE ANOTHER SYSTEM MOVES OUT OF THE GULF OF ALASKA...ACROSS THE PACIFIC NORTHWEST AND INTO THE FORECAST AREA ON THURSDAY. THIS SYSTEM IS STRONGER THAN THE TUESDAY SYSTEM AND HAS A BROAD SURFACE LOW IN THE BALLPARK OF 990MB WHEN IT TRANSVERSES CENTRAL/NORTHERN MN. THE FORECAST AREA REMAINS ON THE WARM SIDE OF THIS SYSTEM AND SOUTH OF THE HEAVIER PRECIP AXIS AT THIS POINT. THE STRONG UPPER JET ACROSS THE PACIFIC BREAKS DOWN LATE THIS WEEK AND THE CONUS ENDS UP WITH A PRONOUNCED LONGWAVE TROUGH OVER THE WEST COAST THAT HEADS EAST NEXT WEEKEND. AT THIS POINT...A BAND OF HEAVY PRECIP WILL LIKELY ACCOMPANY THIS TROUGH...BUT THE MODEL CONSENSUS IS FORECASTING THE PRECIP WELL SOUTH AND EAST OF THE FORECAST AREA. THE NUMERICAL GUIDANCE HAS BEEN A LITTLE INCONSISTENT THE PAST COUPLE DAYS - UNDERSTANDABLE GIVEN HOW FAR OUT WE ARE. THESE TROUGHS THAT DIG INTO THE SOUTHWEST CONUS AND THEN LIFT OUT ALWAYS SEEM TO TAKE LONGER THAN WHAT THE MODELS PREDICT. SO...BRINGING IN PRECIP FRIDAY NIGHT MIGHT BE A LITTLE AGGRESSIVE AT THIS POINT. STILL A LOT OF UNCERTAINTY IN DAYS 6-8. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1052 PM CST SUN DEC 6 2015 LOW STRATUS AND FOG CONTINUE TO BLANKET THE REGION...AND SEE LITTLE IN THE WAY OF IMPROVEMENT AS WEAK WINDS KEEP THE MOISTURE TRAPPED NEAR THE SURFACE. CONDITIONS SHOULD SLOWLY IMPROVE AS WINDS INCREASE ON MONDAY...BUT THE STRATUS WILL REMAIN FOR MOST OF THE DAY...IF NOT ALL...UNTIL WESTERLY WINDS BRING DRIER AIR ACROSS THE REGION. KMSP... CEILINGS SHOULD STAY ABOVE 200FT AT KMSP...AND NOT ANTICIPATING VISBYS TO DROP BELOW 2 MILES DESPITE THE POOR CONDITIONS TO THE WEST. LIFR CONDITIONS WILL LAST THROUGH AT LEAST THE FIRST PART OF THE MORNING...AND MAY NEED TO PUSH THEM BACK EVEN FURTHER. WENT OPTIMISTIC WITH VFR CONDITIONS BY LATE MONDAY EVENING. /OUTLOOK FOR KMSP/ TUE...MVFR -RA POSSIBLE. WINDS SSW 5-10 KTS. WED...VFR. WINDS SW 10 KTS. THU...VFR WITH MVFR/-RA POSSIBLE. WIND W AT 10G20KT. && .MPX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...DENSE FOG ADVISORY UNTIL 8 AM CST MONDAY FOR MNZ042>045-049>052- 057>059-065>068-073>076-082>084-091-092. && $$ SHORT TERM...RAH LONG TERM...CLF AVIATION...JRB
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
329 PM CST MON DEC 7 2015 .SHORT TERM: (Through Late Tonight) Issued at 315 PM CST Mon Dec 7 2015 Low clouds have finally cleared to the east of the MS River as lower trop southwesterly flow increases. I expect this clearing trend to continue through the remainder of the afternoon into the early evening. The late clearing east of the river however will set the stage for fog potential later tonight in IL. Although the surface ridge has retreated, southerly flow across IL is expected to be quite light with dew points in the upper 30s. This should allow for radiational fog to develop by late evening and progress overnight. The HRRR and SREF is highlighting dense fog potential for SW/SC IL and at this time I will be mentioning areas of dense fog into Tuesday morning. Otherwise there will be a couple of batches of high clouds tonight and slightly greater southerly flow to the west of the MS river, keeping temps a bit higher than last night. Glass .LONG TERM: (Tuesday through Next Monday) Issued at 315 PM CST Mon Dec 7 2015 As discussed yesterday, a mild week is on tap with above normal temperatures and a series of fast-moving short waves impacting portions of the area within progressive flow aloft. There will also be boughts of clouds with the shortwaves which will assist modulating temperatures. The strongest shortwave forecast this week will amplify as it traverses the CWA on Tuesday night. Veering south to southwesterly low level flow ahead of the wave should lead to a nice warm-up on Tuesday. There appears to be sufficient forcing/ascent and moistening to merit continuing with slight chance pops on Tuesday night. The GFS is strongest with this system and the most bullish guidance with precipitation, albiet very light. We will see some cooling in the wake of this system for Wednesday, but temperatures will still be a good 10-15 degs above average. The next more prominent short wave will track to our north across the upper MS Valley on Thursday, and this will result in good southwesterly low level flow with high temps 20 or so degrees above average. The very mild weather will continue through the end of the week and into Saturday as a large scale pattern change evolves, featuring the development of a deep and progressive long wave trof over the western U.S. and its eventual eastward migration Sunday into the first part of next week. There is considerable model spread, both deterministic solutions and ensemble members, leading to low confidence in forecast details. Prolonged low level southerly flow will bring low level moisture back into the Mid MS Valley ahead of a NE-SW oriented cold front, setting the stage for an increased thunder threat. At this point there looks to be a good chance of showers and thunderstorms somewhere centered on Saturday night. Glass && .AVIATION: (For the 18z TAFs through 18z Tuesday Afternoon) Issued at 1144 AM CST Mon Dec 7 2015 Main forecast issue continues to be the ceilings for today. IFR/MVFR cigs still expected to lift and scatter out from west to east today across region. Already have some breaks in overcast near KCOU, so have vfr conditions by 20z at KCOU, by 20z-21z for rest of taf sites. Still some concern for fog/stratus development once again for tonight. Best area to see this is KUIN, so added tempo mvfr vsbys betweenn 08z and 12z Tuesday. Otherwise, rest of taf sites have just added scattered stratus for now. Winds to become light and southerly by tonight before picking up to near 15 kts from the south southwest on Tuesday. Specifics for KSTL: Main forecast issue continues to be the ceilings for today. IFR/MVFR cigs still expected to lift and scatter out from west to east today across region. Already have some breaks in overcast near KCOU, so have mvfr clouds scattering out between 20z and 21z for metro area. Still some concern for fog/stratus development once again for tonight, but confidence is low right now, so just added scattered stratus for now. Winds to remain light and southerly before picking up to near 15 kts from the south southwest 16z Tuesday. Byrd && .LSX WATCHES/WARNINGS/ADVISORIES: MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
922 PM MST SUN DEC 6 2015 .UPDATE... SHORTWAVE WITH SOME WARM AIR ADVECTION ALOFT WAS MOVING THROUGH SOUTH CENTRAL MONTANA THIS EVENING AND PRODUCING SOME WEAK ECHOES TO THE EAST OF BILLINGS...ONCE IT GETS OUT OF THE STRONG DOWNSLOPE INFLUENCES. HRRR MODEL PICKED UP ON THIS AND PRODUCED SOME VERY LIGHT QPF WITH THIS FEATURE THIS EVENING. HAVE ADDED SPRINKLES WITH THIS FEATURE AS LOW LEVELS WERE STILL PRETTY DRY. WINDS HAVE GUSTED ABOVE 55 MPH FOR SEVERAL HOURS IN LIVINGSTON THIS EVENING WITH SIMILAR WINDS IN THE UPPER STILLWATER VALLEY. WINDS MAY ACTUALLY TICK UP A BIT TONIGHT AS THE SURFACE LOW OVER BRITISH COLUMBIA FLATTENS SOME OF THE HIGHER SURFACE PRESSURES OVER NORTHERN IDAHO AND NORTHWEST MONTANA...MAKING FOR A MORE FAVORABLE GRADIENT FOR HIGH WINDS AT LIVINGSTON. WIND FORECAST LOOKS GOOD AND DID NOT CHANGE. ALSO...MADE SOME MINOR TWEAKS TO TEMPERATURES OVER THE EAST AS CLOUDS HAVE ROLLED IN AND SLOWED THE COOL DOWN FOR PARTS OF THE AREA. BAKER IS THE EXCEPTION...AS READINGS HAVE ALREADY FALLEN INTO THE LOWER 30S THERE. TWH && .SHORT TERM...VALID FOR MON AND TUE... NO LARGE CHANGES FOR THE AFTERNOON FORECAST PACKAGE. PREVIOUS MODELS SHOWED THAT KLVM WINDS COULD MEET WARNING CRITERIA LATE MON INTO MON EVENING. THE 12Z GFS AND LOCAL STUDIES SHOWED THAT PROBABILITY HAS DROPPED CONSIDERABLY SO NO NEED TO UPGRADE THE ADVISORY AT THIS POINT. WILL ALSO NOT EXTEND ADVISORY IN TIME AS THERE WILL BE A RELATIVE LULL IN THE WINDS ON TUE. IN ADDITION...MIXING POTENTIAL AND GRADIENT ORIENTATION ON MON NIGHT WERE NOT AS FAVORABLE FOR HIGH WINDS FROM BIG TIMBER TO HARLOWTON WITH THIS SET OF MODEL RUNS SO WILL NOT ISSUE ANY WATCHES AT THIS TIME. CROSS-SECTIONS FOR RED LODGE AND KSHR AREAS SHOWED SOME MOUNTAIN WAVE POTENTIAL FOR MON NIGHT IN BOTH AREAS...AND TUE NIGHT IN RED LODGE. HOWEVER...THE TIME-FRAMES FOR THESE POSSIBLE HIGH WINDS WERE VERY SHORT SO CONFIDENCE WAS TOO LOW FOR A HIGHLIGHT FOR THESE AREAS. DID RAISE WIND SPEEDS IN BOTH LOCATIONS MON NIGHT HOWEVER. OTHERWISE...WEAK TROUGH MOVING ACROSS THE REGION WAS GENERATING MID AND HIGH CLOUDS THIS AFTERNOON ON SATELLITE IMAGERY AND SURFACE OBSERVATIONS. TEMPERATURES HAD REACHED THE 40S TO AROUND 50 WITH DEWPOINTS REMAINING LOW. KSHR WAS HOLDING IN THE 30S. KEPT SOME MOUNTAIN POPS IN THE W TONIGHT DUE TO INCOMING PACIFIC MOISTURE. A FLAT WNW FLOW WILL BE OVER THE AREA ON MON WITH A CONTINUED CHANCE OF MOUNTAIN PRECIPITATION. PRESSURE FALLS WILL SPREAD OVER THE AREA FROM W TO E ALLOWING GAP WINDS TO INCREASE AGAIN. THE PRESSURE FALLS WEAKEN AS THEY CROSS THE REGION MON NIGHT AHEAD OF A SHORTWAVE. THE WAVE WILL PUSH A WEAK COLD FRONT THROUGH THE AREA...AND THE PRESSURE GRADIENT WILL BECOME ORIENTED MORE SW TO NE OVERNIGHT. ADVISORY WINDS WILL CONTINUE FOR KLVM AND NYE...AND WINDY CONDITIONS WILL SPREAD FURTHER OUT ONTO THE PLAINS. THE SYSTEM WILL BRING SNOW SHOWERS TO THE SW MOUNTAINS AND A SLIGHT CHANCE TO CHANCE OF RAIN/SNOW SHOWERS TO AREAS E OF KBIL. WINDS IN THE GAP AREAS WILL WEAKEN BEHIND THE SYSTEM ON TUE WITH PRESSURE RISES MOVING THROUGH THE AREA...THEN MORE DISORGANIZED SHORTWAVE ENERGY WILL APPROACH THE REGION TUE NIGHT WITH ACCOMPANYING PRESSURE FALLS. THE PRESSURE GRADIENT WILL TURN MORE N-S AGAIN BRINGING ANOTHER WIND INCREASE TO THE GAP FLOW AREAS. LINGERED POPS OVER THE E ON TUE MORNING WITH THE DEPARTING SYSTEM...OTHERWISE HAD CHANCE MOUNTAIN POPS OVER THE W THROUGH TUE NIGHT. TUE WILL BE AN EVEN WARMER DAY WITH 850 MB TEMPERATURES AROUND +10 DEGREES C. ARTHUR .LONG TERM...VALID FOR WED...THU...FRI...SAT...SUN... STRONG WESTERLY FLOW ALOFT ON WEDNESDAY BEGINS TO WEAKEN THURSDAY NIGHT WITH BROAD TROUGHING DEVELOPING OVER THE WESTERN US FRIDAY INTO SATURDAY. ANOTHER ROUND OF STRONG WEST NORTHWEST FLOW ALOFT REPLACES THIS LULL DURING THE WEEKEND AND MODELS DIFFER ON TIMING. MODELS SHOW A STRONGER PULSE OF WIND SPREADING ACROSS THE PLAINS ON WEDNESDAY AS A COLD FRONT MOVES THROUGH THE REGION WITH 850MB WINDS PROGGED TO REACH 30KTS AND MEX GUIDANCE SHOWING EVEN STRONGER WINDS. EXPECT THE VERY STRONG GAP FLOW WINDS TO BE CONTINUING AT THIS TIME AS WELL AS THE FRONT IS QUICKLY FOLLOWED BY ANOTHER WAVE JUMPING INTO THE LEESIDE TROUGH. MAY SEE LESS OF A GAP FLOW PATTERN AND MORE OF A STRONG WIND PATTERN FOR BIG TIMBER AND HARLOWTON AREAS BUT TIMING WILL PLAY A ROLE SO KEPT GAP FLOW WIND SPEEDS THE SAME AND RAISED WINDS OVER THE PLAINS. STILL BREEZY ON THURSDAY BUT GAP FLOW WINDS WILL DECREASE AND DEFINITELY LESS WIND ACROSS THE REGION FRIDAY AND SATURDAY...POSSIBLY RETURNING SUNDAY. PRECIPITATON IN THE WESTERLY FLOW WILL CONTINUE TO IMPACT WEST FACING ASPECTS BUT SHOWER ACTIVITY REACHING THE PLAINS AND WILL NOT AMOUNT TO MUCH...AND MAY FOR THE MOST PART FALL AS RAIN SHOWERS WEDNESDAY. TEMPERATURES ON WEDNESDAY WILL BE IN THE 50S BEFORE A COOLING TREND THURSDAY INTO THE WEEKEND BUT COOLING ONLY TO NORMAL FOR THIS TIME OF YEAR. BORSUM && .AVIATION... STRONG GAP FLOW WINDS WILL PERSIST AT KLVM AND ALONG THE FOOTHILLS WITH GUSTS OF 40KT OR GREATER THROUGH MONDAY. VFR CONDITIONS WILL PREVAIL WITH SOME HIGHER MOUNTAIN OBSCURATIONS IN SNOW SHOWERS. BORSUM && .PRELIMINARY POINT TEMP/POPS... MON TUE WED THU FRI SAT SUN ----------------------------------------------------------- BIL 032/051 038/057 041/058 033/048 029/041 026/040 025/041 00/N 11/N 12/W 22/W 31/B 21/E 11/E LVM 035/048 043/054 046/052 031/045 026/036 022/034 021/036 11/N 32/W 14/W 23/W 31/N 21/N 12/J HDN 026/053 034/058 037/062 031/050 027/043 022/041 021/043 00/U 22/W 11/B 31/N 31/B 22/W 12/W MLS 030/053 033/057 037/062 034/050 027/042 022/038 019/041 10/U 32/W 12/W 21/N 21/B 12/W 11/B 4BQ 029/054 032/060 033/062 031/051 028/043 022/039 020/042 10/U 22/W 11/B 30/N 22/W 22/W 11/N BHK 024/051 030/053 032/060 033/049 026/040 019/035 017/038 10/U 32/W 12/W 31/N 22/W 12/J 11/B SHR 024/052 031/057 033/062 029/052 025/040 020/038 017/041 00/U 11/B 11/B 11/N 32/W 22/W 11/B && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...WIND ADVISORY IN EFFECT UNTIL MIDNIGHT MST MONDAY NIGHT FOR ZONES 65-66. WY...NONE. && $$ WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1138 AM CST MON DEC 7 2015 .UPDATE... ISSUED AT 735 AM CST MON DEC 7 2015 FOG HAS LIFTED OR WILL CONTINUE TO LIFT IN WRN IA THE NEXT HOUR OR SO. DENSE FOG ADVISORY CANCELLED A BIT EARLY. && .SHORT TERM...(TODAY THROUGH WEDNESDAY) ISSUED AT 328 AM CST MON DEC 7 2015 MAIN NEAR TERM CONCERN CONTINUES TO BE AN EXTENSIVE AREA OF DENSE FOG ACROSS OUR WESTERN IOWA COUNTIES WHERE WE ALREADY HAVE A DENSE FOG ADVISORY. SATELLITE IMAGERY SHOWS THIS CONTINUING INCH TO THE EAST HOWEVER HIGH CLOUDS SPILLING OVERHEAD ARE MAKING IT TOUGH TO SEE THE LOWER CLOUDS/VISIBILITIES. CALLS TO A FEW COUNTIES ACKNOWLEDGED SOME ICE/FROST ON VEHICLES AND GRASSY SURFACES BUT SO FAR NO IMPACTS ON ROADS WITH ROAD TEMPERATURES STILL IN THE UPPER 30S. BOTH HRRR AND RAP INDICATE THE FOG/STRATUS DECK RAPIDLY SLIDING EAST OF THE CWA BY MID MORNING. DID REMOVE MONONA COUNTY FROM THE ADVISORY AND EXTENDED THE REMAINDER OF THE ADVISORY UNTIL 14Z. OTHERWISE...LATEST WATER VAPOR IMAGERY LOOP SHOWS A WEAK SHORTWAVE TROUGH EXTENDING FROM EASTERN MT THROUGH NORTH CENTRAL COLORADO. AT THE SURFACE...A TROUGH EXTENDS SOUTH FROM LOW PRESSURE OVER SOUTH CENTRAL CANADA INTO WESTERN KANSAS AND EVENTUALLY THE TEXAS PANHANDLE. THE WEAK SHORTWAVE WILL CONTINUE TO MOVE EAST THROUGH NEBRASKA TODAY AND INTO THE GREAT LAKES REGION BY EARLY TONIGHT. THE SFC TROUGH PASSAGE WILL BE BRIEF/WEAK AND SHOULD HAVE LITTLE AFFECT ON ANY SENSIBLE WEATHER EXCEPT FOR A BRIEF/WEAK WIND SHIFT THIS AFTERNOON FROM SOUTHWEST TO NORTHWEST. MILD CONDITIONS WILL BE THE PRIMARY STORY THIS WEEK WITH TEMPERATURES RUNNING CLOSE TO 15 TO EVEN 20 DEGREES ABOVE NORMAL. ANOTHER MID LEVEL SHORTWAVE WILL DRIFT THROUGH THE AREA TUESDAY WHICH BRINGS INCREASED LARGE SCALE LIFT...BUT LACK OF MOISTURE KEEP POPS OUT OF THE FORECAST. MAY ONLY SEE AN INCREASE IN HIGH/MID CLOUDS BUT A FEW SPRINKLES CANNOT BE COMPLETELY RULED OUT. AN ASSOCIATED SFC TROUGH WILL PUSH THROUGH TUESDAY AFTERNOON TURNING WINDS AGAIN FROM SOUTHWEST TO NORTHWEST WHICH SHOULD ALLOW DECENT MIXING TO PUSH HIGHS INTO THE MID TO UPPER 50S...WITH SOME LOWER 60S POSSIBLE ACROSS OUR SOUTHERN COUNTIES DEPENDING ON EXTENT OF CLOUD COVER. .LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY) ISSUED AT 328 AM CST MON DEC 7 2015 PATTERN BECOMES MORE ACTIVE TOWARD THE WEEKEND WHEN A DEEP TROUGH DIGS ACROSS THE WESTERN STATES AND A FAIRLY TIGHT BAROCLINIC ZONE SETS UP ACROSS THE NATION`S MID SECTION BY FRIDAY. THIS CONTINUES TO LOOK LIKE A LOW QPF EVENT FOR OUR CWA AS MAIN RIBBON OF QPF DEVELOPS ALONG THE FRONTAL BOUNDARY WELL TO OUR SOUTHEAST BY SATURDAY NIGHT/EARLY SUNDAY. MAIN PCPN FOR OUR AREA MIGHT BE SOME OVERRUNNING...BUT DETAILS THIS FAR OUT ARE STILL A LITTLE SKETCHY. && .AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 1135 AM CST MON DEC 7 2015 VFR CONDITIONS WILL PREVAIL THROUGH THE PERIOD WITH INCREASING HIGH LEVEL CLOUDS AFTER 00Z. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ UPDATE...MILLER SHORT TERM...KERN LONG TERM...KERN AVIATION...FOBERT
AREA FORECAST DISCUSSION...UPDATED
NWS OMAHA/VALLEY NE
737 AM CST MON DEC 7 2015 .UPDATE... ISSUED AT 735 AM CST MON DEC 7 2015 FOG HAS LIFTED OR WILL CONTINUE TO LIFT IN WRN IA THE NEXT HOUR OR SO. DENSE FOG ADVISORY CANCELLED A BIT EARLY. && .SHORT TERM...(TODAY THROUGH WEDNESDAY) ISSUED AT 328 AM CST MON DEC 7 2015 MAIN NEAR TERM CONCERN CONTINUES TO BE AN EXTENSIVE AREA OF DENSE FOG ACROSS OUR WESTERN IOWA COUNTIES WHERE WE ALREADY HAVE A DENSE FOG ADVISORY. SATELLITE IMAGERY SHOWS THIS CONTINUING INCH TO THE EAST HOWEVER HIGH CLOUDS SPILLING OVERHEAD ARE MAKING IT TOUGH TO SEE THE LOWER CLOUDS/VISIBILITIES. CALLS TO A FEW COUNTIES ACKNOWLEDGED SOME ICE/FROST ON VEHICLES AND GRASSY SURFACES BUT SO FAR NO IMPACTS ON ROADS WITH ROAD TEMPERATURES STILL IN THE UPPER 30S. BOTH HRRR AND RAP INDICATE THE FOG/STRATUS DECK RAPIDLY SLIDING EAST OF THE CWA BY MID MORNING. DID REMOVE MONONA COUNTY FROM THE ADVISORY AND EXTENDED THE REMAINDER OF THE ADVISORY UNTIL 14Z. OTHERWISE...LATEST WATER VAPOR IMAGERY LOOP SHOWS A WEAK SHORTWAVE TROUGH EXTENDING FROM EASTERN MT THROUGH NORTH CENTRAL COLORADO. AT THE SURFACE...A TROUGH EXTENDS SOUTH FROM LOW PRESSURE OVER SOUTH CENTRAL CANADA INTO WESTERN KANSAS AND EVENTUALLY THE TEXAS PANHANDLE. THE WEAK SHORTWAVE WILL CONTINUE TO MOVE EAST THROUGH NEBRASKA TODAY AND INTO THE GREAT LAKES REGION BY EARLY TONIGHT. THE SFC TROUGH PASSAGE WILL BE BRIEF/WEAK AND SHOULD HAVE LITTLE AFFECT ON ANY SENSIBLE WEATHER EXCEPT FOR A BRIEF/WEAK WIND SHIFT THIS AFTERNOON FROM SOUTHWEST TO NORTHWEST. MILD CONDITIONS WILL BE THE PRIMARY STORY THIS WEEK WITH TEMPERATURES RUNNING CLOSE TO 15 TO EVEN 20 DEGREES ABOVE NORMAL. ANOTHER MID LEVEL SHORTWAVE WILL DRIFT THROUGH THE AREA TUESDAY WHICH BRINGS INCREASED LARGE SCALE LIFT...BUT LACK OF MOISTURE KEEP POPS OUT OF THE FORECAST. MAY ONLY SEE AN INCREASE IN HIGH/MID CLOUDS BUT A FEW SPRINKLES CANNOT BE COMPLETELY RULED OUT. AN ASSOCIATED SFC TROUGH WILL PUSH THROUGH TUESDAY AFTERNOON TURNING WINDS AGAIN FROM SOUTHWEST TO NORTHWEST WHICH SHOULD ALLOW DECENT MIXING TO PUSH HIGHS INTO THE MID TO UPPER 50S...WITH SOME LOWER 60S POSSIBLE ACROSS OUR SOUTHERN COUNTIES DEPENDING ON EXTENT OF CLOUD COVER. .LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY) ISSUED AT 328 AM CST MON DEC 7 2015 PATTERN BECOMES MORE ACTIVE TOWARD THE WEEKEND WHEN A DEEP TROUGH DIGS ACROSS THE WESTERN STATES AND A FAIRLY TIGHT BAROCLINIC ZONE SETS UP ACROSS THE NATION`S MID SECTION BY FRIDAY. THIS CONTINUES TO LOOK LIKE A LOW QPF EVENT FOR OUR CWA AS MAIN RIBBON OF QPF DEVELOPS ALONG THE FRONTAL BOUNDARY WELL TO OUR SOUTHEAST BY SATURDAY NIGHT/EARLY SUNDAY. MAIN PCPN FOR OUR AREA MIGHT BE SOME OVERRUNNING...BUT DETAILS THIS FAR OUT ARE STILL A LITTLE SKETCHY. && .AVIATION...(12Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 520 AM CST MON DEC 7 2015 FOG HAS BEEN JUST EAST OF KOMA AND WILL PROBABLY STAY THERE BASED ON MOST RECENT DATA FROM WEB CAMS IN COUNCIL BLUFFS. OTHERWISE LOOK FOR VFR CONDITIONS THROUGH THE PERIOD. SOUTHERLY WINDS WILL INCREASE AND BECOME WEST OR SOUTHWEST TODAY...THEN DROP BACK TO SOUTH AND BECOME LIGHTER FOR TONIGHT. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ UPDATE...MILLER SHORT TERM...KERN LONG TERM...KERN AVIATION...MILLER
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
520 AM CST MON DEC 7 2015 .SHORT TERM...(TODAY THROUGH WEDNESDAY) ISSUED AT 328 AM CST MON DEC 7 2015 MAIN NEAR TERM CONCERN CONTINUES TO BE AN EXTENSIVE AREA OF DENSE FOG ACROSS OUR WESTERN IOWA COUNTIES WHERE WE ALREADY HAVE A DENSE FOG ADVISORY. SATELLITE IMAGERY SHOWS THIS CONTINUING INCH TO THE EAST HOWEVER HIGH CLOUDS SPILLING OVERHEAD ARE MAKING IT TOUGH TO SEE THE LOWER CLOUDS/VISIBILITIES. CALLS TO A FEW COUNTIES ACKNOWLEDGED SOME ICE/FROST ON VEHICLES AND GRASSY SURFACES BUT SO FAR NO IMPACTS ON ROADS WITH ROAD TEMPERATURES STILL IN THE UPPER 30S. BOTH HRRR AND RAP INDICATE THE FOG/STRATUS DECK RAPIDLY SLIDING EAST OF THE CWA BY MID MORNING. DID REMOVE MONONA COUNTY FROM THE ADVISORY AND EXTENDED THE REMAINDER OF THE ADVISORY UNTIL 14Z. OTHERWISE...LATEST WATER VAPOR IMAGERY LOOP SHOWS A WEAK SHORTWAVE TROUGH EXTENDING FROM EASTERN MT THROUGH NORTH CENTRAL COLORADO. AT THE SURFACE...A TROUGH EXTENDS SOUTH FROM LOW PRESSURE OVER SOUTH CENTRAL CANADA INTO WESTERN KANSAS AND EVENTUALLY THE TEXAS PANHANDLE. THE WEAK SHORTWAVE WILL CONTINUE TO MOVE EAST THROUGH NEBRASKA TODAY AND INTO THE GREAT LAKES REGION BY EARLY TONIGHT. THE SFC TROUGH PASSAGE WILL BE BRIEF/WEAK AND SHOULD HAVE LITTLE AFFECT ON ANY SENSIBLE WEATHER EXCEPT FOR A BRIEF/WEAK WIND SHIFT THIS AFTERNOON FROM SOUTHWEST TO NORTHWEST. MILD CONDITIONS WILL BE THE PRIMARY STORY THIS WEEK WITH TEMPERATURES RUNNING CLOSE TO 15 TO EVEN 20 DEGREES ABOVE NORMAL. ANOTHER MID LEVEL SHORTWAVE WILL DRIFT THROUGH THE AREA TUESDAY WHICH BRINGS INCREASED LARGE SCALE LIFT...BUT LACK OF MOISTURE KEEP POPS OUT OF THE FORECAST. MAY ONLY SEE AN INCREASE IN HIGH/MID CLOUDS BUT A FEW SPRINKLES CANNOT BE COMPLETELY RULED OUT. AN ASSOCIATED SFC TROUGH WILL PUSH THROUGH TUESDAY AFTERNOON TURNING WINDS AGAIN FROM SOUTHWEST TO NORTHWEST WHICH SHOULD ALLOW DECENT MIXING TO PUSH HIGHS INTO THE MID TO UPPER 50S...WITH SOME LOWER 60S POSSIBLE ACROSS OUR SOUTHERN COUNTIES DEPENDING ON EXTENT OF CLOUD COVER. .LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY) ISSUED AT 328 AM CST MON DEC 7 2015 PATTERN BECOMES MORE ACTIVE TOWARD THE WEEKEND WHEN A DEEP TROUGH DIGS ACROSS THE WESTERN STATES AND A FAIRLY TIGHT BAROCLINIC ZONE SETS UP ACROSS THE NATION`S MID SECTION BY FRIDAY. THIS CONTINUES TO LOOK LIKE A LOW QPF EVENT FOR OUR CWA AS MAIN RIBBON OF QPF DEVELOPS ALONG THE FRONTAL BOUNDARY WELL TO OUR SOUTHEAST BY SATURDAY NIGHT/EARLY SUNDAY. MAIN PCPN FOR OUR AREA MIGHT BE SOME OVERRUNNING...BUT DETAILS THIS FAR OUT ARE STILL A LITTLE SKETCHY. && .AVIATION...(12Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 520 AM CST MON DEC 7 2015 FOG HAS BEEN JUST EAST OF KOMA AND WILL PROBABLY STAY THERE BASED ON MOST RECENT DATA FROM WEB CAMS IN COUNCIL BLUFFS. OTHERWISE LOOK FOR VFR CONDITIONS THROUGH THE PERIOD. SOUTHERLY WINDS WILL INCREASE AND BECOME WEST OR SOUTHWEST TODAY...THEN DROP BACK TO SOUTH AND BECOME LIGHTER FOR TONIGHT. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...DENSE FOG ADVISORY UNTIL 8 AM CST THIS MORNING FOR IAZ055-056- 069-079-080-090-091. && $$ SHORT TERM...KERN LONG TERM...KERN AVIATION...MILLER
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
343 AM CST MON DEC 7 2015 .SHORT TERM...(TODAY THROUGH WEDNESDAY) ISSUED AT 328 AM CST MON DEC 7 2015 MAIN NEAR TERM CONCERN CONTINUES TO BE AN EXTENSIVE AREA OF DENSE FOG ACROSS OUR WESTERN IOWA COUNTIES WHERE WE ALREADY HAVE A DENSE FOG ADVISORY. SATELLITE IMAGERY SHOWS THIS CONTINUING INCH TO THE EAST HOWEVER HIGH CLOUDS SPILLING OVERHEAD ARE MAKING IT TOUGH TO SEE THE LOWER CLOUDS/VISIBILITIES. CALLS TO A FEW COUNTIES ACKNOWLEDGED SOME ICE/FROST ON VEHICLES AND GRASSY SURFACES BUT SO FAR NO IMPACTS ON ROADS WITH ROAD TEMPERATURES STILL IN THE UPPER 30S. BOTH HRRR AND RAP INDICATE THE FOG/STRATUS DECK RAPIDLY SLIDING EAST OF THE CWA BY MID MORNING. DID REMOVE MONONA COUNTY FROM THE ADVISORY AND EXTENDED THE REMAINDER OF THE ADVISORY UNTIL 14Z. OTHERWISE...LATEST WATER VAPOR IMAGERY LOOP SHOWS A WEAK SHORTWAVE TROUGH EXTENDING FROM EASTERN MT THROUGH NORTH CENTRAL COLORADO. AT THE SURFACE...A TROUGH EXTENDS SOUTH FROM LOW PRESSURE OVER SOUTH CENTRAL CANADA INTO WESTERN KANSAS AND EVENTUALLY THE TEXAS PANHANDLE. THE WEAK SHORTWAVE WILL CONTINUE TO MOVE EAST THROUGH NEBRASKA TODAY AND INTO THE GREAT LAKES REGION BY EARLY TONIGHT. THE SFC TROUGH PASSAGE WILL BE BRIEF/WEAK AND SHOULD HAVE LITTLE AFFECT ON ANY SENSIBLE WEATHER EXCEPT FOR A BRIEF/WEAK WIND SHIFT THIS AFTERNOON FROM SOUTHWEST TO NORTHWEST. MILD CONDITIONS WILL BE THE PRIMARY STORY THIS WEEK WITH TEMPERATURES RUNNING CLOSE TO 15 TO EVEN 20 DEGREES ABOVE NORMAL. ANOTHER MID LEVEL SHORTWAVE WILL DRIFT THROUGH THE AREA TUESDAY WHICH BRINGS INCREASED LARGE SCALE LIFT...BUT LACK OF MOISTURE KEEP POPS OUT OF THE FORECAST. MAY ONLY SEE AN INCREASE IN HIGH/MID CLOUDS BUT A FEW SPRINKLES CANNOT BE COMPLETELY RULED OUT. AN ASSOCIATED SFC TROUGH WILL PUSH THROUGH TUESDAY AFTERNOON TURNING WINDS AGAIN FROM SOUTHWEST TO NORTHWEST WHICH SHOULD ALLOW DECENT MIXING TO PUSH HIGHS INTO THE MID TO UPPER 50S...WITH SOME LOWER 60S POSSIBLE ACROSS OUR SOUTHERN COUNTIES DEPENDING ON EXTENT OF CLOUD COVER. .LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY) ISSUED AT 328 AM CST MON DEC 7 2015 PATTERN BECOMES MORE ACTIVE TOWARD THE WEEKEND WHEN A DEEP TROUGH DIGS ACROSS THE WESTERN STATES AND A FAIRLY TIGHT BAROCLINIC ZONE SETS UP ACROSS THE NATION`S MID SECTION BY FRIDAY. THIS CONTINUES TO LOOK LIKE A LOW QPF EVENT FOR OUR CWA AS MAIN RIBBON OF QPF DEVELOPS ALONG THE FRONTAL BOUNDARY WELL TO OUR SOUTHEAST BY SATURDAY NIGHT/EARLY SUNDAY. MAIN PCPN FOR OUR AREA MIGHT BE SOME OVERRUNNING...BUT DETAILS THIS FAR OUT ARE STILL A LITTLE SKETCHY. && .AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 1123 PM CST SUN DEC 6 2015 THE CONCERN IS WHETHER A DECK OF STRATUS ABOUT 200 FEET AGL AND VISIBILITY LESS THAN 1/4...WHICH IS ABOUT 18 MILES EAST OF KOMA... WILL MAKE IT THE SITE OR NOT. HRRR/RAP MODEL CONTINUES TO SUGGEST THIS WHILE OTHER MODELS DO NOT. FOR NOW HAVE INCLUDED A TEMPO GROUP AT KOMA WITH 2SM AND SCT005 FROM 07-11Z...AND WILL UPDATE IF NEEDED. OTHERWISE...IT`S A VFR FORECAST WITH BROKEN TO SCATTERED CIRRUS. LIGHT SOUTH SOUTHEAST WINDS NOW...VEERING TO WEST SOUTHWEST THROUGH THE MORNING. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...DENSE FOG ADVISORY UNTIL 8 AM CST THIS MORNING FOR IAZ055-056- 069-079-080-090-091. && $$ SHORT TERM...KERN LONG TERM...KERN AVIATION...DEWALD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
721 PM EST TUE DEC 8 2015 .SYNOPSIS... WEAK HIGH PRESSURE WILL SHIFT OFFSHORE LATE TONIGHT. AN UPPER LEVEL DISTURBANCE WILL APPROACH THE MOUNTAINS FROM THE WEST LATE TONIGHT...THEN TRACK EAST ACROSS THE CAROLINAS AND MID-ATLANTIC WEDNESDAY EVENING. && .NEAR TERM /THROUGH TONIGHT/... AS OF 308 PM TUESDAY... MAIN FORECAST CHALLENGE...A CARRY-OVER FROM TODAY...IS THE CONTINUED EVOLUTION OF THE SLOWLY ERODING/SHRINKING AREA OF STRATUS(LEFT-OVER FROM THIS MORNING`S DENSE FOG)OVER THE EASTERN PIEDMONT AND CENTRAL/SOUTHERN COASTAL PLAIN. HRRR AND RAP SOUNDINGS BOTH SUGGEST A RAPID RETURN TO LOW CLOUDS AND FOG THIS EVENING BETWEEN 00 TO 06Z...WITH EXPANSION OF THE STRATUS/FOG LAYER INLAND INTO THE CENTRAL AND WESTERN PIEDMONT OVERNIGHT AS LIGHT SOUTHERLY RETURN FLOW DEVELOPS ACROSS THE AREA AS THE WEAK SFC HIGH SHIFTS OFFSHORE. WILL BEEF UP CLOUD COVER TO ACCOUNT FOR WHAT COULD BE A RATHER EXTENSIVE STRATUS CLOUD DECK OVERNIGHT AND WILL INTRODUCE FOG ACROSS THE EASTERN HALF(PERSISTENCE). LOWS IN THE UPPER 30S TO LOWER 40S. && .SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/... AS OF 300 PM TUESDAY... AMPLIFYING SHORTWAVE ENERGY EJECTING OUT ACROSS THE CENTRAL PLAINS WILL REACH THE TN AND OHIO VALLEY ON WEDNESDAY AND WILL MOVE THROUGH THE AREA WEDNESDAY NIGHT. MOISTURE WILL BE QUITE LIMITED WITH THIS SYSTEM AND MODELS HAVE BEEN BACK AND FORTH WITH LITTLE CONTINUITY IN SHOWING LIGHT QPF ACROSS THE AREA AS THE SYSTEM MOVES THROUGH THE AREA LATE WEDNESDAY AFTERNOON AND EVENING. A BROAD AREA OF WARM ADVECTION COUPLED WITH INCREASING DIVERGENCE IN THE RIGHT ENTRANCE REGION OF THE UPPER JET SHOULD SUPPORT AN AREA OF LIGHT RAIN SHOWERS...MAINLY FROM US 1 EASTWARD BETWEEN 18Z WED TO 06Z THURSDAY. HIGHS RANGING FROM UPPER 50S NORTHWEST TO MID 60S SOUTHEAST. LOWS IN THE UPPER 30S TO LOWER 40S FAR NW TO MID/UPPER 40S SOUTHEAST. && .LONG TERM /THURSDAY THROUGH TUESDAY/... AS OF 308 PM TUESDAY... BEHIND A DEPARTING SHORTWAVE ON THURSDAY...HEIGHTS WILL GRADUALLY RISE THROUGH AT LEAST THE FIRST HALF OF THE LONG TERM PERIOD. THESE HEIGHT RISES WILL BE GREATEST OVER THE WEEKEND AS A STRONG RIDGE IS PROGGED TO DEVELOP OVER THE SOUTHEAST GULF/NORTHWEST ATLANTIC. THE GRADUAL RISE OF LOW LEVEL THICKNESS VALUES WILL SUPPORT A DEGREE OR TWO INCREASE IN WARMTH EACH DAY...WITH UPPER 60S TO LOWER 70S EXPECTED BY SATURDAY AND SUNDAY. OVERNIGHT LOWS WILL ALSO SHOW A WARMING TREND THROUGH THE FIRST HALF OF THE PERIOD...WITH 40S INITIALLY...THEN MODERATING INTO THE 50S. THE NEXT CHANCE OF PRECIP WILL COME LATE SUNDAY NIGHT INTO MONDAY WITH THE APPROACH OF OUR NEXT FRONT. HOWEVER...THERE IS SOME MODEL DISAGREEMENT AS THE ECMWF IS A GOOD 24 HOURS SLOWER THAN THE GFS...SO THIS WILL BE MONITORED IN THE COMING DAYS IN ORDER TO BETTER TIME THE PRECIP. REGARDLESS...AS HAS BEEN THE CASE RECENTLY...THE MAIN STORM TRACK WILL BE WELL NORTH OF THE REGION... WITH JUST THE TRAILING COLD FRONT CROSSING OUR AREA ON SUNDAY NIGHT/MONDAY (OR MONDAY NIGHT/TUESDAY). BEHIND THE FRONT...COOLER AND DRIER CONDITIONS ARE EXPECTED ON TUESDAY. TEMPS WILL BE TEMPERED SOME (COMPARED TO PREVIOUS DAYS) ON MONDAY GIVEN THE CLOUDS AND RAIN...WITH LOW TO UPPER 60S EXPECTED. THEN UPPER 50S TO LOWER 60S ARE EXPECTED ON TUESDAY BEHIND THE FRONT. OVERNIGHT LOWS WILL RETURN TO THE UPPER 30S AND 40S BY EARLY NEXT WEEK. && .AVIATION /00Z WEDNESDAY THROUGH MONDAY/... AS OF 720 PM TUESDAY... 24-HR TAF PERIOD: STRATUS AND FOG WILL DEVELOP OVERNIGHT ACROSS THE AREA. FAVOR FOG FORMATION FOR EASTERN AREAS OF THE STATE... INCLUDING KRWI AND KFAY... WHERE WINDS WILL BE NEAR CALM CLOSER TO THE CENTER OF THE HIGH LOCATED AT THE NC COAST. STRATUS IS MORE LIKELY FURTHER WEST. REGARDLESS OF THE MANIFESTATION... IFR CONDITIONS ARE LIKELY AT ALL SITES. VFR CONDITIONS WILL RETURN AFTER 15Z. LOOKING AHEAD: A DRY COLD FRONT WILL MOVE THROUGH THE AREA WEDNESDAY NIGHT WITH DRY VFR CONDITIONS EXPECTED THROUGH THE REMAINDER OF THE WEEK. SOUTHERLY RETURN FLOW IN ADVANCE OF THE NEXT COLD FRONTAL PASSAGE COULD SUNDAY NIGHT COULD SUPPORT AREAS OF FOG/STRATUS SUNDAY MORNING. && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...VINCENT NEAR TERM...CBL SHORT TERM...CBL LONG TERM...KRD AVIATION...30/CBL
AREA FORECAST DISCUSSION
NWS BISMARCK ND
927 PM CST TUE DEC 8 2015 .UPDATE... ISSUED AT 925 PM CST TUE DEC 8 2015 BASED ON THE LATEST RADAR INFORMATION AND CONSSHORT GUIDANCE HAVE ADJUSTED THE POPS A BIT FURTHER SOUTH. HRRR STILL KEEPS THE PRECIP FURTHER NORTH THAN CONSSHORT BUT WILL TREND CLOSER TO CONSSHORT. UPDATE ISSUED AT 627 PM CST TUE DEC 8 2015 WILL CONTINUE TO FOLLOW THE LATEST HRRR MODEL THAT KEEPS THE PRECIP ACROSS THE NORTH TONIGHT. THE CONSSHORT GUIDANCE LOOKS A BIT TOO FAR SOUTH AND TOO WET AT THIS TIME. LIKE THE CURRENT POPS WITH JUST A SLIGHT CHANCE OF RAIN THIS EVENING BUT A THREAT FRO SOME FREEZING RAIN NORTH CENTRAL...OVER THE TURTLE MOUNTAINS TOWARDS MIDNIGHT. OTHERWISE UPDATED THE CURRENT CONDITIONS. && .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 250 PM CST TUE DEC 8 2015 VERY WARM WEATHER IS EXPECTED WEDNESDAY IN MEAN ZONAL FLOW ALOFT. ANOTHER BATCH OF VERY MILD AIR ORIGINATING OVER THE PACIFIC OCEAN WILL SURGE EASTWARD INTO THE NORTHERN PLAINS BY WEDNESDAY AHEAD OF A 500-MB SHORTWAVE CRASHING INTO THE NORTHERN ROCKIES. THE 12 UTC MODEL GUIDANCE CALLS FOR 850-MB TEMPERATURES TO RISE INTO THE +10 TO +12 C RANGE OVER SOUTHWESTERN ND BY WEDNESDAY...AND WITH MEAN WESTERLY LOW-LEVEL THROUGH AT LEAST EARLY AFTERNOON...HIGHS WILL SOAR TO NEAR-RECORD LEVELS IN MANY AREAS. WE UTILIZED 12 UTC BIAS- CORRECTED MOS TO BUILD THE HIGH TEMPERATURE FORECAST WEDNESDAY... WHICH CALLS FOR HIGHS RANGING FROM 50 AT JAMESTOWN TO THE LOWER 60S IN SOUTHWESTERN ND. THE CURRENT DAILY RECORD HIGHS OF 56 F AT WILLISTON AND 60 F AT DICKINSON COULD BE TIED OR BROKEN. EXPECTED HIGH-LEVEL CLOUDS AND A LATE-DAY TURN TOWARD MORE SOUTHERLY WINDS IN THE BOUNDARY LAYER KEPT US FROM ADVERTISING EVEN WARMER HIGHS. OTHERWISE...WE DO HAVE A SLIGHT CHANCE OF LIGHT RAIN OR FREEZING RAIN OVER NORTHWEST AND NORTH CENTRAL ND AFTER 06 UTC TONIGHT AND CONTINUING INTO EARLY WEDNESDAY MORNING. THAT MENTION IS TIED TO THE APPROACHING MID-LEVEL WARM FRONT...BUT THERE IS LITTLE SIGNAL OF MOISTURE IN THE DETERMINISTIC MODEL OUTPUT AND IN MANY LOCALES SURFACE TEMPERATURES WILL RISE ABOVE 32 F OVERNIGHT...SO THE AREA WITH A RISK OF LIGHT FREEZING RAIN WILL LIKELY BE SMALL IN SPACE AND TIME...AND CENTERED MAINLY FROM BOTTINEAU TOWARD ROLLA. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 250 PM CST TUE DEC 8 2015 STRONG WINDS AND POSSIBLE MIXED PRECIPITATION HIGHLIGHT THE EARLY PORTION OF THE EXTENDED PERIOD WITH A COOLING TREND AS WE HEAD INTO THE UPCOMING WEEKEND. A STRONG S/WV TROUGH MOVES EAST ACROSS THE NORTHERN PLAINS WEDNESDAY NIGHT. MODELS ARE STILL INDICATING ALL RAIN ACROSS THE SOUTHERN TWO THIRDS OF THE STATE WHERE AIR TEMPERATURES REMAINS ABOVE FREEZING...WITH A WINTRY MIX POSSIBLE FAR NORTH WHERE TEMPERATURES WILL BE CLOSER TO FREEZING OR BELOW. STRONG CAA IN THE WAKE OF WED NIGHTS WAVE WILL SEE DAYTIME TEMPERATURES 10-20 DEGREES COLDER THURSDAY COMPARED TO WEDNESDAY...WITH ALSO WRAP AROUND RAIN OR SNOW SURGING SOUTH AND EAST ACROSS THE STATE. STRONG WINDS REMAIN A CONCERN LATE WED NIGHT INTO THURSDAY BEHIND THE SFC LOW WITH STRONG PRESSURE RISES DEVELOPING EAST ACROSS THE DAKOTAS. MODELS REMAIN OUT OF SYNC AS FAR AS THE LOW PRESSURE PLACEMENT AND TIMING OF WINDS...AS WELL AS MIXING LAYER HEIGHTS AND THUS POTENTIAL WIND GUSTS. WE OPTED TO HOLD OFF ON ANY HEADLINES AND LET THE MID SHIFT TONIGHT RELOOK LATEST 00Z GUIDANCE WHICH HOPEFULLY NARROWS THINGS DOWN BETTER. YET ANOTHER POTENT S/WV TROUGH MOVES ACROSS THE REGION LATE THURSDAY NIGHT INTO FRIDAY. THIS TIME THE ATMOSPHERIC PROFILE WILL BE COLD ENOUGH FOR ALL SNOW. THIS FEATURE WILL BE MORE INTERESTING WITH A MORE DEFINED SFC TROUGH AXIS EXTENDING INTO OUR AREA ALONG WITH STRONGER UPPER LEVEL JET DYNAMICS. WILL MONITOR THIS PERIOD CLOSE OVER THE NEXT DAY OR TWO WITH NEAR ADVISORY ACCUMULATIONS STILL POSSIBLE. HOWEVER...LATEST MODELS ARE MORE PROGRESSIVE SO FORECAST SNOW AMOUNTS HAVE BEEN REDUCED TO MORE IN THE 1-2 INCH RANGE. REINFORCED SHOT OF COLDER AIR FOLLOWS FOR THE WEEKEND...WHICH ALSO LOOKS DRY. WILL NEED TO MONITOR MODELS CLOSELY FOR EARLY TO MID NEXT WEEK AS STRONG ENERGY MOVES INTO THE PACIFIC NORTHWEST LATE THIS WEEKEND...AND WHICH MAY EVENTUALLY IMPACT THE NORTHERN PLAINS. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING) ISSUED AT 627 PM CST TUE DEC 8 2015 A WARM FRONT ACROSS EASTERN MONTANA WILL MOVE EAST THROUGH NORTH DAKOTA TONIGHT. THE FRONT WILL BE THE FOCUS FOR ISOLATED RAIN/FREEZING ACROSS FAR NORTHERN ND TUESDAY NIGHT. VFR ACROSS THE REGION. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...WAA SHORT TERM...CJS LONG TERM...NH AVIATION...WAA
AREA FORECAST DISCUSSION
NWS BISMARCK ND
635 PM CST TUE DEC 8 2015 .UPDATE... ISSUED AT 627 PM CST TUE DEC 8 2015 WILL CONTINUE TO FOLLOW THE LATEST HRRR MODEL THAT KEEPS THE PRECIP ACROSS THE NORTH TONIGHT. THE CONSSHORT GUIDANCE LOOKS A BIT TOO FAR SOUTH AND TOO WET AT THIS TIME. LIKE THE CURRENT POPS WITH JUST A SLIGHT CHANCE OF RAIN THIS EVENING BUT A THREAT FRO SOME FREEZING RAIN NORTH CENTRAL...OVER THE TURTLE MOUNTAINS TOWARDS MIDNIGHT. OTHERWISE UPDATED THE CURRENT CONDITIONS. && .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 250 PM CST TUE DEC 8 2015 VERY WARM WEATHER IS EXPECTED WEDNESDAY IN MEAN ZONAL FLOW ALOFT. ANOTHER BATCH OF VERY MILD AIR ORIGINATING OVER THE PACIFIC OCEAN WILL SURGE EASTWARD INTO THE NORTHERN PLAINS BY WEDNESDAY AHEAD OF A 500-MB SHORTWAVE CRASHING INTO THE NORTHERN ROCKIES. THE 12 UTC MODEL GUIDANCE CALLS FOR 850-MB TEMPERATURES TO RISE INTO THE +10 TO +12 C RANGE OVER SOUTHWESTERN ND BY WEDNESDAY...AND WITH MEAN WESTERLY LOW-LEVEL THROUGH AT LEAST EARLY AFTERNOON...HIGHS WILL SOAR TO NEAR-RECORD LEVELS IN MANY AREAS. WE UTILIZED 12 UTC BIAS- CORRECTED MOS TO BUILD THE HIGH TEMPERATURE FORECAST WEDNESDAY... WHICH CALLS FOR HIGHS RANGING FROM 50 AT JAMESTOWN TO THE LOWER 60S IN SOUTHWESTERN ND. THE CURRENT DAILY RECORD HIGHS OF 56 F AT WILLISTON AND 60 F AT DICKINSON COULD BE TIED OR BROKEN. EXPECTED HIGH-LEVEL CLOUDS AND A LATE-DAY TURN TOWARD MORE SOUTHERLY WINDS IN THE BOUNDARY LAYER KEPT US FROM ADVERTISING EVEN WARMER HIGHS. OTHERWISE...WE DO HAVE A SLIGHT CHANCE OF LIGHT RAIN OR FREEZING RAIN OVER NORTHWEST AND NORTH CENTRAL ND AFTER 06 UTC TONIGHT AND CONTINUING INTO EARLY WEDNESDAY MORNING. THAT MENTION IS TIED TO THE APPROACHING MID-LEVEL WARM FRONT...BUT THERE IS LITTLE SIGNAL OF MOISTURE IN THE DETERMINISTIC MODEL OUTPUT AND IN MANY LOCALES SURFACE TEMPERATURES WILL RISE ABOVE 32 F OVERNIGHT...SO THE AREA WITH A RISK OF LIGHT FREEZING RAIN WILL LIKELY BE SMALL IN SPACE AND TIME...AND CENTERED MAINLY FROM BOTTINEAU TOWARD ROLLA. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 250 PM CST TUE DEC 8 2015 STRONG WINDS AND POSSIBLE MIXED PRECIPITATION HIGHLIGHT THE EARLY PORTION OF THE EXTENDED PERIOD WITH A COOLING TREND AS WE HEAD INTO THE UPCOMING WEEKEND. A STRONG S/WV TROUGH MOVES EAST ACROSS THE NORTHERN PLAINS WEDNESDAY NIGHT. MODELS ARE STILL INDICATING ALL RAIN ACROSS THE SOUTHERN TWO THIRDS OF THE STATE WHERE AIR TEMPERATURES REMAINS ABOVE FREEZING...WITH A WINTRY MIX POSSIBLE FAR NORTH WHERE TEMPERATURES WILL BE CLOSER TO FREEZING OR BELOW. STRONG CAA IN THE WAKE OF WED NIGHTS WAVE WILL SEE DAYTIME TEMPERATURES 10-20 DEGREES COLDER THURSDAY COMPARED TO WEDNESDAY...WITH ALSO WRAP AROUND RAIN OR SNOW SURGING SOUTH AND EAST ACROSS THE STATE. STRONG WINDS REMAIN A CONCERN LATE WED NIGHT INTO THURSDAY BEHIND THE SFC LOW WITH STRONG PRESSURE RISES DEVELOPING EAST ACROSS THE DAKOTAS. MODELS REMAIN OUT OF SYNC AS FAR AS THE LOW PRESSURE PLACEMENT AND TIMING OF WINDS...AS WELL AS MIXING LAYER HEIGHTS AND THUS POTENTIAL WIND GUSTS. WE OPTED TO HOLD OFF ON ANY HEADLINES AND LET THE MID SHIFT TONIGHT RELOOK LATEST 00Z GUIDANCE WHICH HOPEFULLY NARROWS THINGS DOWN BETTER. YET ANOTHER POTENT S/WV TROUGH MOVES ACROSS THE REGION LATE THURSDAY NIGHT INTO FRIDAY. THIS TIME THE ATMOSPHERIC PROFILE WILL BE COLD ENOUGH FOR ALL SNOW. THIS FEATURE WILL BE MORE INTERESTING WITH A MORE DEFINED SFC TROUGH AXIS EXTENDING INTO OUR AREA ALONG WITH STRONGER UPPER LEVEL JET DYNAMICS. WILL MONITOR THIS PERIOD CLOSE OVER THE NEXT DAY OR TWO WITH NEAR ADVISORY ACCUMULATIONS STILL POSSIBLE. HOWEVER...LATEST MODELS ARE MORE PROGRESSIVE SO FORECAST SNOW AMOUNTS HAVE BEEN REDUCED TO MORE IN THE 1-2 INCH RANGE. REINFORCED SHOT OF COLDER AIR FOLLOWS FOR THE WEEKEND...WHICH ALSO LOOKS DRY. WILL NEED TO MONITOR MODELS CLOSELY FOR EARLY TO MID NEXT WEEK AS STRONG ENERGY MOVES INTO THE PACIFIC NORTHWEST LATE THIS WEEKEND...AND WHICH MAY EVENTUALLY IMPACT THE NORTHERN PLAINS. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING) ISSUED AT 627 PM CST TUE DEC 8 2015 A WARM FRONT ACROSS EASTERN MONTANA WILL MOVE EAST THROUGH NORTH DAKOTA TONIGHT. THE FRONT WILL BE THE FOCUS FOR ISOLATED RAIN/FREEZING ACROSS FAR NORTHERN ND TUESDAY NIGHT. VFR ACROSS THE REGION. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...WAA SHORT TERM...CJS LONG TERM...NH AVIATION...WAA
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1142 PM CST SUN DEC 6 2015 .UPDATE... ISSUED AT 1136 PM CST SUN DEC 6 2015 BROAD 500 MB SHORT WAVED TROUGH MOVING INTO WRN MANITOBA AND THE WRN DAKOTAS AT 0530 UTC. AREA OF HIGH CLOUDS AHEAD OF IT OVER THE AREA. LOW CLOUDS AND FOG HANGING JUST EAST AND SOUTHEAST...THOUGH HAVE MOVED INTO SE WADENA COUNTY (STAPLES). HAVENT MUCH ADVANCE NORTHWEST LAST HOUR OR TWO...BUT LOW CLOUDS ARE BEING MASKED BY HIGH CLOUDS NOW. WITH HIGH CLOUDS MOVING OVER THE LOW CLOUD/FOG AREA IT IS HOPED THE FOG WILL DISSIPATE SOME. WRN EDGE OF LOW CLOUDS MAY YET PARTS OF THE FAR ERN FCST AREA. OTHERWISE CIRRUS AND A SOUTH BREEZE. TEMPS HAVE BEEN HOLDING STEADY SINCE THEIR DROP IN THE EARLY EVENING AND EXPECT TO SEE NOT A LOT OF TEMP CHANGE OVERNIGHT. && .SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT) ISSUED AT 300 PM CST SUN DEC 6 2015 THE MAIN CHALLENGE WILL BE TEMPS AND QPF CHANCES TUE INTO TUE NIGHT. MODELS ARE IN FAIRLY GOOD AGREEMENT...WITH SOME TIMING AND PLACEMENT ISSUES WITH QPF TUE/TUE NIGHT. WE PREFER THE GFS THAT HAS A DECENT HANDLE ON CURRENT SET UP. FOR TONIGHT...SOUTHERLY WINDS SHOULD REMAIN NEAR 10KT FOR ALL BUT THE FAR EAST. THE HRRR INDICATES SOME FOG ONCE AGAIN IN THE FAR EAST SO WILL ADD. TEMPS WILL CONTINUE WELL ABOVE NORMAL. ON MONDAY...ANOTHER VERY MILD DAY WITH WESTERLY FLOW ONCE AGAIN. TEMPS SHOULD BE SIMILAR TO TODAY AND MAY EVEN BE A BIT WARMER WITH MORE WESTERLY WINDS NEAR THE SFC. FOR MONDAY NIGHT...CLOUDS WILL INCREASE IN THE WEST LATE AND WINDS SHOULD REMAIN MIXED ENOUGH TO KEEP TEMPS NEAR 30. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 300 PM CST SUN DEC 6 2015 FOR TUE...A SHORTWAVE MOVES THROUGH WITH SOME RAIN...FREEZING RAIN EARLY TRANSITIONING TO RAIN FAIRLY QUICKLY. THE GFS HAS SOME QPF SOUTH WITH THE NAM FURTHER NORTH...WITH THE ECMWF MORE BROADBRUSHED QPF. ON TUE NIGHT...ANY PRECIP WILL MOVE INTO THE EAST. IT SHOULD BE MAINLY RAIN THAT COULD MIX WITH A FEW FLAKES BEFORE ENDING. ON WED...MORE VERY WARM CHINOOK MODIFIED AIR MOVES IN. TEMPS SHOULD BE INTO THE 40S PERHAPS EVEN WARMER FOR AREAS THAT HAVE NO SNOW. FOR WEDNESDAY NIGHT THROUGH SUNDAY...MODELS DEPICT A MUDDY ZONAL FLOW PATTERN THROUGH THE MIDWEEK PERIOD WITH A TRANSITION TO A DEEP CENTRAL CONUS TROF FOR THE WEEKEND. THUS WILL EXPECT SEASONABLY MILD CONDITIONS AND PERIODS OF LIGHT RAIN CHANGING TO SNOW LATE ON THURSDAY... WITH A TURN TO SOMEWHAT COOLER CONDITIONS AND A GREATER CHANCE FOR WIDEPSREAD LIGHT SNOW FROM LATE FRIDAY INTO SUNDAY. SNOWFALL AMOUNTS ARE STILL EXPECTED TO REMAIN SCANT AT LEAST THROUGH SATURDAY... SO NET IMPACTS OF THE EXPECTED LIGHT SNOW ON OVERALL TEMPERATURE PATTERNS SHOULD BE SLIGHT. THUS WILL CONTINUE TO BUMP TEMPERATURES AROUND 10 DEGREES ABOVE LONG TERM NORMALS YET ON SATURDAY /EXPECTED HIGHS NEAR THE FREEZING POINT/ AND AROUND 5 DEGREES ABOVE NORMAL ON SUNDAY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1136 PM CST SUN DEC 6 2015 VFR THRU THE PD WITH CIRRUS MOVING THROUGH. THICKEST OVERNIGHT WITH THIN OR CLEAR PATCHES MONDAY MIDDAY INTO THE AFTN/EVE. SOUTH WINDS 5 TO 15 KTS WILL BECOME WEST-SOUTHWEST WEST OF THE RRV MONDAY AFTN. ONLY QUESTION YET IS BEMIDJI AREA AS WRN FRINGE OF LOW CLOUDS AND FOG MAY IMPACT THE AREA FOR A TIME LATE NIGHT OR EARLY MONDAY MORNING. INCLUDED A TEMPO GROUP 09-13Z UTC FOR SOME MVFR VSBY IN FOG AND SCATTERED LOW CLOUD AT BJI TAF SITE. NOT ENOUGH CONFIDENCE TO GO IFR CIGS...THOUGH A PD WOULD NOT BE SUPRISING. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ UPDATE...RIDDLE SHORT TERM...DK LONG TERM...GUST/DK AVIATION...RIDDLE
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
114 AM EST MON DEC 7 2015 .SYNOPSIS... WEAK LOW PRESSURE WILL MOVE THROUGH THE REGION OVERNIGHT INTO MONDAY. HIGH PRESSURE WILL BUILD BACK IN FOR TUESDAY. ANOTHER LOW PRESSURE SYSTEM WILL AFFECT THE AREA ON WEDNESDAY. && .NEAR TERM /THROUGH TODAY/... CLOUDS ARE BECOMING THE KEY ELEMENT TO THE FORECAST TONIGHT...FORCING A FEW CHANGES THIS EVENING. CURRENT SATELLITE IMAGERY SHOWS CIRRUS DEPARTING OHIO AND KENTUCKY TO THE EAST...WITH A BROKEN DECK OF MID CLOUDS (8KFT-12KFT) EXTENDING ACROSS SOUTHERN MICHIGAN...NORTHEASTERN INDIANA...AND WESTERN OHIO. BEHIND THIS...A SOLID DECK OF STRATOCUMULUS (3KFT-6KFT) IS PERHAPS THE MOST EASILY DISTINGUISHED OF THE FEATURES ON THE 11U-3.9U SATELLITE PRODUCT. THIS CLOUD DECK HAS JUST ENTERED THE FORECAST AREA...IN ADVANCE OF THE WEAK SURFACE AND MID-LEVEL LOW PRESSURE CENTERS...AND WILL CONTINUE TO SPREAD INTO OHIO AND KENTUCKY OVER THE NEXT SEVERAL HOURS. AHEAD OF THESE CLOUDS...TEMPERATURES HAVE TAKEN A REMARKABLY QUICK TURN FOR THE BASEMENT IN CENTRAL OHIO...WITH VALUES ALREADY SEVERAL DEGREES BELOW FREEZING EAST OF COLUMBUS. UNTIL THE CLOUDS GET INTO THE REGION...THESE TEMPERATURES SHOULD CONTINUE TO DROP. HOWEVER...CONDITIONS UNDER THE STRATOCUMULUS DECK HAVE BEEN QUITE A BIT WARMER...WITH TEMPERATURES NEAR 40 IN CENTRAL INDIANA...AND IN THE MID 40S IN WEST-CENTRAL INDIANA. A COMPLETELY NEW SET OF TEMPERATURE GRIDS HAS BEEN CREATED...INDICATING STEADY TEMPERATURES IN THE WESTERN HALF OF THE CWA...AND SOME ADDITIONAL COOLING IN THE EAST BEFORE RISING AGAIN AFTER 06Z. SKY GRIDS WERE ALSO ADJUSTED TO INCREASE VALUES ONCE THE STRATOCUMULUS DECK ARRIVES. PRECIPITATION AMOUNTS TO THE WEST HAVE BEEN VERY LIGHT...WITH GENERALLY TRACE TO 0.02" REPORTS ON THE HOURLY OBSERVATIONS. THE AREA OF SHOWERS MAY EXPAND VERY SLIGHTLY IN COVERAGE AND INTENSITY OVER THE NEXT FEW HOURS...BUT THE CHANCES OF MEASURABLE PRECIPITATION FOR THE ILN FORECAST AREA STILL SEEM WELL COVERED BY THE CURRENT ARRANGEMENT OF POPS. BASED ON RADAR TRENDS...THE POPS WERE ADJUSTED NORTHWARD BY ONE OR TWO TIERS OF COUNTIES. A TIMING COMPROMISE BETWEEN THE HRRR (SLIGHTLY FAST) AND NAM/GFS (SLIGHTLY SLOW) MATCHED WELL WITH THE PREVIOUS FORECAST...AND WAS RETAINED. A WARM LAYER AT AROUND 950MB WILL ENSURE THAT PRECIPITATION THAT FALLS REMAINS LIQUID...THOUGH SURFACE TEMPERATURES AT ONSET MAY BE IN THE MID 30S. && .SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/... UPPER LOW MOVES ACROSS THE CWA MONDAY MORNING. CONTINUED LOW POPS ACROSS THE SOUTHEAST PORTION OF THE CWA UNTIL THE LOW EXITS. BEHIND IT...ENOUGH DRYING IN THE MID LEVELS ALONG WITH SUBSIDENCE FROM WEAK HIGH PRESSURE WILL ALLOW FOR SOME SUNSHINE TO RETURN FOR THE AFTERNOON AND THAT WILL KEEP MAXIMA ABOVE AVERAGE FOR THIS TIME OF THE YEAR. HIGH PRESSURE MOVES TO THE EAST MONDAY NIGHT...AND SOUTHERLY FLOW AROUND THE HIGH WILL LIKELY BRING AN INCREASE IN CLOUDS MONDAY NIGHT BUT IT SHOULD REMAIN DRY. GENERALLY ZONAL FLOW ALOFT WILL BE IN PLACE TUESDAY/TUESDAY NIGHT WITH DRY CONDITIONS AND ABOVE NORMAL TEMPERATURES. && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... AN UPPER LEVEL S/WV WILL TRAVERSE OUR REGION ON WEDNESDAY. THIS FEATURE...ALONG WITH A SFC TROF AXIS...WILL BRING A CHANCE OF SHOWERS. SYSTEM MOVES EAST WEDNESDAY NIGHT...FOLLOWED TO A RETURN OF DRY WEATHER ON THURSDAY. THE FORECAST IS STILL A LITTLE BIT UNCLEAR AS WE HEAD INTO THE END OF THE WEEK...ESPECIALLY IN REGARDS TO AREAL COVERAGE AND PROBABILITY OF PCPN. THE FLOW DOES BECOME MORE AMPLIFIED WITH A LARGE SCALE MID LEVEL TROUGH DIGGING OUT FROM THE WESTERN U.S. AND RIDGING DEVELOPING OVER THE EASTERN U.S. S/WV ENERGY FOR THURSDAY/FRIDAY STILL VARYS AMONGST THE MODELS IN TERMS OF HOW STRONG/DEEP IT WILL BE AS IT PASSES THROUGH THE GREAT LAKES. HAVE KEPT POPS ON THE LOW SIDE DUE TO HIGH UNCERTAINTY. FOR SATURDAY...LOOKS LIKE MID LEVEL RIDGING AND A WARM FRONT WILL LIFT THROUGH OUR REGION. WARMER TEMPERATURES AND SOME WAA SHOWERS WILL BE POSSIBLE. LOW PRESSURE AND A SLOW MOVING COLD FRONT WILL ENCROACH THE REGION ON SUNDAY WITH A HIGHER THREAT FOR SHOWERS EXPECTED. IT WILL CONTINUE TO BE WARMER THAN NORMAL THROUGH THE PERIOD WITH TEMPERATURES WARMING INTO THE 60S BY THE WEEKEND...WHICH IS SOME 20 DEGREES ABOVE NORMAL FOR MID DECEMBER. THESE VALUES MAY CHALLENGE RECORD HIGHS. && .AVIATION /06Z MONDAY THROUGH FRIDAY/... AN UPPER LEVEL DISTURBANCE WILL MOVE ACROSS THE AREA OVERNIGHT AND INTO THE MORNING HOURS ON MONDAY. LIGHT RAIN SHOWERS WILL MOVE ACROSS THE AREA. VSBYS WILL GENERALLY STAY VFR HOWEVER VSBYS MAY BRIEFLY BE REDUCED WITH FOG AND SHOWER ACTIVITY. SHOWER ACTIVITY WILL MOVE OUT DURING THE MORNING HOURS. CLOUD COVER WILL DECREASE DURING THE DAY ON MONDAY. WINDS WILL BE LIGHT AND LESS THAN 10 KNOTS THROUGH THE TAF PERIOD. THERE ARE INDICATIONS OF POSSIBLE FOG AND STRATUS DEVELOPMENT MONDAY NIGHT. WENT MORE WITH A FOG SOLUTION HOWEVER WENT WITH SCATTERED LOWER CLOUDS AT THE LONGER KCVG TAF SITE. IN ADDITION BROUGHT DOWN VSBYS AT THE LONGER KCVG TAF OVERNIGHT MONDAY NIGHT. OUTLOOK...MVFR AND POSSIBLY IFR VSBYS ARE POSSIBLE MONDAY NIGHT. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...NONE. KY...NONE. IN...NONE. && $$ SYNOPSIS...BPP NEAR TERM...HATZOS SHORT TERM...BPP LONG TERM...HICKMAN AVIATION...NOVAK
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
830 PM EST TUE DEC 8 2015 .SYNOPSIS... A SERIES OF LOW PRESSURE SYSTEMS WILL TRACK WELL WEST OF PA LATE IN THE WEEK AS AN ANOMALOUS UPPER RIDGE BUILDS ALONG THE EAST COAST. TEMPERATURES WILL BE WARMER THAN NORMAL FOR MUCH OF THE NEXT WEEK OR TWO. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... LAST PATCH OF FOG PERSISTING INTO THE EVENING ACROSS PORTIONS OF THE CENTRAL MTNS...AS WAA CLOUD DECK IN THE 2-4KFT LYR OVERSPREADS THE AREA AHEAD OF WSWRLY LL JET ENTERING WESTERN PA. NEAR TERM MDL DATA INDICATE THIS AREA OF CLOUDS WILL SHIFT EAST ACROSS THE AREA TONIGHT WITH PASSAGE OF LL JET...PERHAPS TEMPERING THE FOG THREAT ACROSS OUR EASTERN ZONES LATE TONIGHT. ELSEWHERE...CLEARING BEHIND THIS LL JET FEATURE SHOULD ALLOW WIDESPREAD FOG/LOW CIGS TO FORM ONCE AGAIN OVERNIGHT...WHICH WILL BE SLOW TO DISSIPATE EARLY WEDNESDAY MORNING. LATEST SREF...HRRR/RAP AND DOWNSCALED NAM ALL TARGET THE CENTRAL MTNS FOR THE GREATEST RISK OF DENSE FOG. HOWEVER...A QUICK LOOK AT 22Z DWPT DEPRESSIONS SUGGEST SOME FOG IS LIKELY ACROSS THE ENTIRE AREA. STILL SOME UNCERTAINTY WITH REGARDS TO HOW DENSE FOG WILL BE...AS LATEST RAP SOUNDINGS IMPLY LOW CIGS RATHER THAN DENSE FOG POSSIBLE. IN ADDITION...NAMDNG INDICATING LOWEST VSBYS WED AM ON THE RIDGETOPS...INDICATIVE OF LOW CIGS. WILL DELAY DECISION ON ANY POSSIBLE ADVISORIES UNTIL LATER THIS EVENING. EXPECT MINS TONIGHT TO BE FAIRLY UNIFORM...GENERALLY WITHIN A FEW DEGREES OF 33F. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH 6 PM WEDNESDAY/... WED MORNING FOG WILL BE SLOW TO DISSIPATE...BUT INCREASING BOUNDARY LAYER FLOW AHEAD OF ANOTHER SHEARING UPPER WAVE AND AMPLIFYING UPPER FLOW SHOULD FINALLY HELP SCOUR THINGS OUT MORE THAN WE`VE SEEN IN A FEW DAYS. MOISTURE INCREASES SUFFICIENTLY TO INTRODUCE A CHANCE OF SHOWERS IN THE AFTERNOON...SO EXPECT AN END TO THE FOG BY THEN. BEST CHANCE OF SHOWERS COMES WEDNESDAY NIGHT WITH THE SHEARING UPPER WAVE...SO NO SIGNIFICANT SHOWER ACTIVITY IS EXPECTED WED AFTERNOON. HIGHS WILL MOSTLY BE IN THE 40S NORTH AND CENTRAL...AND UPPER 40S TO LOWER 50S SOUTH ON WEDNESDAY. && .LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/... THE MAIN STORY FOR THE LONG TERM IS UNSEASONABLY MILD WEATHER...AS WE EXPECT TEMPERATURES ARE EXPECTED TO REMAIN ABOVE- NORMAL RIGHT INTO EARLY NEXT WEEK. AS FOR PRECIPITATION...A WEAKENING TROUGH OF LOW PRESSURE COULD BRING A FEW SHOWERS ACROSS CENTRAL PA WED NIGHT INTO THU...WITH ANOTHER TROUGH PROVIDING A SLIGHT CHC FOR SHOWERS ACROSS MAINLY THE NORTH AND WEST THU NITE INTO FRI. SATURDAY INTO SUNDAY WILL SEE A SIGNIFICANT UPPER-LEVEL RIDGE BUILD OVER THE EAST COAST. INCREASINGLY SOUTHERLY FLOW SHOULD BRING IN EVEN MILDER TEMPERATURES THIS WEEKEND...WITH SOME LOCATIONS SEEING AFTERNOON HIGHS APPROACHING 20 DEGREES ABOVE- NORMAL. A MORE SIGNIFICANT STORM SYSTEM WILL TRACK ACROSS THE GREAT LAKES AND INTO NEW ENGLAND MONDAY INTO TUESDAY...DRAGGING A COLD FRONT ACROSS CENTRAL PA. THIS SYSTEM WILL BE ACCOMPANIED BY A PERIOD OF SHOWERY WEATHER...AND FOLLOWED BY A COOL-DOWN BY THE MIDDLE OF NEXT WEEK. && .AVIATION /01Z WEDNESDAY THROUGH SUNDAY/... HIGH PRESSURE ALONG THE ATLC COAST WILL PROVIDE GENERALLY CLEAR SKIES AND LIGHT WINDS THIS EVENING...ALLOWING REDEVELOPMENT OR THICKENING OF LOW FOG/LOW LEVEL CIGS ESPECIALLY AT LOCATIONS THAT REMAINED LOW TODAY. AREA OF MID CLOUDS WILL SPREAD WEST TO EAST OVERNIGHT AHEAD OF WEATHER SYSTEM OVER THE PLAINS. THIS MAY HELP TO DISRUPT LOWER CONDS...AT LEAST TEMPORARILY OVERNIGHT. SLOW IMPROVEMENT IS EXPECTED WEDNESDAY AS SFC WINDS INCREASE AHD OF THE APPROACHING WEATHER SYSTEM. THIS SYSTEM WILL BRING SHOWERS TO THE REGION WED NIGHT. OUTLOOK... TUE NIGHT-WED NIGHT...CHANCE FOR MVFR CIGS. THU-FRI...MVFR POSS NW. SAT...MVFR WITH CHC SHRA. SUN...VFR. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...DEVOIR/LAMBERT NEAR TERM...FITZGERALD SHORT TERM...DEVOIR/LAMBERT LONG TERM...EVANEGO AVIATION...DEVOIR/GARTNER
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
609 PM EST TUE DEC 8 2015 .SYNOPSIS... A SERIES OF LOW PRESSURE SYSTEMS WILL TRACK WELL WEST OF PA LATE IN THE WEEK AS AN ANOMALOUS UPPER RIDGE BUILDS ALONG THE EAST COAST. TEMPERATURES WILL BE WARMER THAN NORMAL FOR MUCH OF THE NEXT WEEK OR TWO. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... LAST PATCH OF FOG PERSISTING INTO THE EVENING ACROSS PORTIONS OF THE CENTRAL MTNS...AS WAA CLOUD DECK IN THE 2-4KFT LYR OVERSPREADS THE AREA AHEAD OF WSWRLY LL JET ENTERING WESTERN PA. NEAR TERM MDL DATA INDICATE THIS AREA OF CLOUDS WILL SHIFT EAST ACROSS THE AREA TONIGHT WITH PASSAGE OF LL JET...PERHAPS TEMPERING THE FOG THREAT ACROSS OUR EASTERN ZONES LATE TONIGHT. ELSEWHERE...CLEARING BEHIND THIS LL JET FEATURE SHOULD ALLOW WIDESPREAD FOG/LOW CIGS TO FORM ONCE AGAIN OVERNIGHT...WHICH WILL BE SLOW TO DISSIPATE EARLY WEDNESDAY MORNING. LATEST SREF...HRRR/RAP AND DOWNSCALED NAM ALL TARGET THE CENTRAL MTNS FOR THE GREATEST RISK OF DENSE FOG. HOWEVER...A QUICK LOOK AT 22Z DWPT DEPRESSIONS SUGGEST SOME FOG IS LIKELY ACROSS THE ENTIRE AREA. STILL SOME UNCERTAINTY WITH REGARDS TO HOW DENSE FOG WILL BE...AS LATEST RAP SOUNDINGS IMPLY LOW CIGS RATHER THAN DENSE FOG POSSIBLE. IN ADDITION...NAMDNG INDICATING LOWEST VSBYS WED AM ON THE RIDGETOPS...INDICATIVE OF LOW CIGS. WILL DELAY DECISION ON ANY POSSIBLE ADVISORIES UNTIL LATER THIS EVENING. EXPECT MINS TONIGHT TO BE FAIRLY UNIFORM...GENERALLY WITHIN A FEW DEGREES OF 33F. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH 6 PM WEDNESDAY/... WED MORNING FOG WILL BE SLOW TO DISSIPATE...BUT INCREASING BOUNDARY LAYER FLOW AHEAD OF ANOTHER SHEARING UPPER WAVE AND AMPLIFYING UPPER FLOW SHOULD FINALLY HELP SCOUR THINGS OUT MORE THAN WE`VE SEEN IN A FEW DAYS. MOISTURE INCREASES SUFFICIENTLY TO INTRODUCE A CHANCE OF SHOWERS IN THE AFTERNOON...SO EXPECT AN END TO THE FOG BY THEN. BEST CHANCE OF SHOWERS COMES WEDNESDAY NIGHT WITH THE SHEARING UPPER WAVE...SO NO SIGNIFICANT SHOWER ACTIVITY IS EXPECTED WED AFTERNOON. HIGHS WILL MOSTLY BE IN THE 40S NORTH AND CENTRAL...AND UPPER 40S TO LOWER 50S SOUTH ON WEDNESDAY. && .LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/... THE MAIN STORY FOR THE LONG TERM IS UNSEASONABLY MILD WEATHER...AS WE EXPECT TEMPERATURES ARE EXPECTED TO REMAIN ABOVE- NORMAL RIGHT INTO EARLY NEXT WEEK. AS FOR PRECIPITATION...A WEAKENING TROUGH OF LOW PRESSURE COULD BRING A FEW SHOWERS ACROSS CENTRAL PA WED NIGHT INTO THU...WITH ANOTHER TROUGH PROVIDING A SLIGHT CHC FOR SHOWERS ACROSS MAINLY THE NORTH AND WEST THU NITE INTO FRI. SATURDAY INTO SUNDAY WILL SEE A SIGNIFICANT UPPER-LEVEL RIDGE BUILD OVER THE EAST COAST. INCREASINGLY SOUTHERLY FLOW SHOULD BRING IN EVEN MILDER TEMPERATURES THIS WEEKEND...WITH SOME LOCATIONS SEEING AFTERNOON HIGHS APPROACHING 20 DEGREES ABOVE- NORMAL. A MORE SIGNIFICANT STORM SYSTEM WILL TRACK ACROSS THE GREAT LAKES AND INTO NEW ENGLAND MONDAY INTO TUESDAY...DRAGGING A COLD FRONT ACROSS CENTRAL PA. THIS SYSTEM WILL BE ACCOMPANIED BY A PERIOD OF SHOWERY WEATHER...AND FOLLOWED BY A COOL-DOWN BY THE MIDDLE OF NEXT WEEK. && .AVIATION /00Z WEDNESDAY THROUGH SUNDAY/... PATCHY FOG CONTS TO DISSIPATE ACROSS THE CENTRAL MOUNTAIN VALLEYS. ELSEWHERE SKY CONDS RANGE FROM VFR TO MVFR CIGS IN DECREASING STRATUS. SOME DECREASING CLOUDS TONIGHT WILL ALLOW FOG TO FORM AGAIN OVERNIGHT...FOLLOWED BY MVFR CIGS ON WED MORNING AND AFTERNOON. OUTLOOK... TUE NIGHT-WED NIGHT...CHANCE FOR MVFR CIGS. THU-FRI...MVFR POSS NW. SAT...MVFR WITH CHC SHRA. SUN...VFR. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...DEVOIR/LAMBERT NEAR TERM...FITZGERALD SHORT TERM...DEVOIR/LAMBERT LONG TERM...EVANEGO AVIATION...DEVOIR
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
645 AM EST MON DEC 7 2015 .SYNOPSIS... A MOISTURE-STARVED SOUTHERN STREAM SHORTWAVE WILL TRACK ACROSS SOUTHERN PA LATE TODAY. A SERIES OF LOW PRES SYSTEMS WILL TRACK WELL WEST OF PA LATE IN THE WEEK...AS AN ANOMALOUS UPPER RIDGE BUILDS ALONG THE EAST COAST. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 11-3.9U LOOP AT 11Z SHOWING AREAS OF DENSE VALLEY FROM EXTENDING FROM THE CENTRAL MTNS EASTWARD INTO THE SUSQ VALLEY. STRONG INVERSION AND LOW DECEMBER SUN ANGLE WILL ALLOW FOG TO PERSIST THROUGH LATE AM. DENSE FOG ADV REMAINS UP THRU 16Z. APPROACHING UPPER LOW IS PRODUCING A BATCH OF SHOWERS ACROSS THE OHIO VALLEY AT 11Z. HOWEVER...ALL NEAR TERM MDL GUIDANCE TRACKS WEAKENING SFC LOW WELL SOUTH OF PA...WITH AIR MASS OVR PA REMAINING TOO DRY TO SUPPORT PRECIP. THEREFORE...WILL CONTINUE TO CARRY ONLY A SLIGHT CHC OF SHOWERS ACROSS SOMERSET/BEDFORD COUNTIES LATER TODAY. UPSTREAM SATL IMAGERY AND MDL RH FIELDS SUGGEST PATCHY AM FOG WILL GIVE WAY TO MSUNNY SKIES ACROSS MOST OF CENTRAL PA. EXCEPTION WILL BE SOMERSET/BEDFORD COS...WHERE INCREASING CLOUDS EXPECTED THIS AFTN. HIGHS WILL BE FAIRLY UNIFORM...RANGING FROM 45-50F OVER MOST OF THE REGION. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/... UPPER LOW WILL PUSH EAST OF PA TONIGHT...AS SFC RIDGE BUILDS IN FROM THE NORTHWEST. MCLEAR SKIES AND A NEARLY CALM WIND SHOULD ONCE AGAIN PROMOTE AREAS OF LOW CLOUDS/FOG. WEAKEST GRADIENT AND REGION MOST FAVORABLE FOR FOG WILL BE ACROSS THE ALLEGHENY PLATEAU WITH ONLY PATCHY FOG LIKELY FURTHER EAST ACROSS THE SUSQ VALLEY. SFC RIDGE OVR THE REGION SHOULD ENSURE A DRY TUESDAY WITH PASSING UPPER LVL SHORTWAVE LIKELY TO PRODUCE NO MORE THAN SCT MID/HIGH LVL CLOUDINESS. SUPERBLEND AND NEW ECME MOS INDICATE HIGHS IN THE 40S. && .LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... THE MAIN FORECAST STORY THRU THE END OF THIS WEEK IS THE CONTINUED MILD TEMPERATURES...AS ZONAL FLOW FLOODS THE CONUS WITH PACIFIC AIR. NAEFS AND ECENS OUTPUT SHOWING A SERIES OF SFC LOWS TRACKING NORTHWARD THRU THE GRT LKS LATE NEXT WEEK...AS ANOMALOUS UPPER RIDGE BUILDS ALONG THE E COAST. HAVE INCLUDED A CHC OF SHRA ASSOC WITH SHORTWAVE LIFTING UP THE OHIO VALLEY LATE WED/EARLY THU. OTHERWISE...THE EXTENDED FCST APPEARS DRY AND INCREASINGLY WARM BENEATH BUILDING RIDGE. GEFS PLUME DATA AND ECEME MOS SUPPORT MIN TEMPS ABOVE FREEZING ACROSS THE ENTIRE CWA THU-SUN AND MAX TEMPS AT LEAST 15F ABV NORMAL. SOME CHC OF SHOWERS TOWARD THE END OF THE FCST PERIOD...AS SOUTHERN STREAM SHORTWAVE LIFTS THRU THE GRT LKS...PUSHING A COLD FRONT INTO PA. LATEST GEFS OUTPUT SUGGESTS FRONT AND SHOWER THREAT COULD ARRIVE BY SUNDAY...WHILE ECENS IS A SLOWER SOLUTION WITH DRY/VERY WARM WX PERSISTING THRU SUNDAY. && .AVIATION /12Z MONDAY THROUGH FRIDAY/... THE BIGGEST FORECAST QUESTION OVERNIGHT IS FOG FORMATION. CURRENT HRRR AND RAP RUNS DECREASE THE FOG THROUGH MOST OF THE CENTRAL PA BY 09Z...HOWEVER GIVEN THE LOW DEWPOINT DEPRESSIONS...CALM WINDS AN STRONG INVERSION EXPECT CENTRAL TAF SITES AOO...UNV...IPT TO SEE IFR AND LOWER CIGS AND VSBYS OVERNIGHT UNTIL MORNING. THERE HAS BEEN SOME VARIABILITY IN VSBYS DUE TO THE FOG MOVEMENT. EXPECT TEMPO GROUPS OF 1/4 MILE AT TIMES AT UNV AND AOO...AND MVFR RESTRICTIONS DUE TO THE PATCHY NATURE OF THE FORMING FOG THROUGH THE FIRST HALF OF THE OVERNIGHT HOURS. AS THE FOG/MIST BECOMES ENTRENCHED BETWEEN 06Z TO 09Z...VSBYS WILL DECREASE AND REMAIN IFR AND LOWER. MAINLY VFR CONDS WILL PREVAIL AT JST AND BFD...DUE TO THE DRY NW FLOW ALOFT. FOG/MIST THROUGH THE LOWER SUSQ IS AN INTERESTING CONUNDRUM. THOUGH SOME HIGH CLOUDS PERSIST...CALMING WINDS...DEWPOINT DEPRESSIONS OF CURRENT 4 DEGREES OR LESS...SHOULD ALLOW FOR FOR DENSE FOG OVERNIGHT. EXPECT PERIODS OF IFR VSBYS AND LOWER ESPECIALLY NEAR SUNRISE. THE FOG WILL SLOWLY LIFT/DISSIPATE TOMORROW MORNING...THOUGH QUICKER THAN IT DID ON SUNDAY. SO EXPECT VFR TO RETURN BY 15Z MON AT ALL SITES. A MOISTURE-STARVED SOUTHERN STREAM SHORTWAVE WILL TRACK ACROSS THE AREA MONDAY...POTENTIALLY BRINGING RESTRICTIONS TO KJST LATER MONDAY AND SPREADING INTO MAINLY THE SOUTHERN HALF OF THE STATE MON NIGHT. OUTLOOK... MON-MON NIGHT...CHANCE FOR MVFR CONDITIONS IN -SHRA ACROSS THE SOUTHERN HALF OF PENN. TUE...NO SIG WX EXPECTED. TUE NIGHT-WED NIGHT...CHANCE FOR MVFR CIGS. THU-FRI...MVFR POSS NW. && .CTP WATCHES/WARNINGS/ADVISORIES... DENSE FOG ADVISORY UNTIL 11 AM EST THIS MORNING FOR PAZ012- 017>019-025>028-034>036-041-045-046-049>053-056>059-063>066. && $$ SYNOPSIS...FITZGERALD NEAR TERM...FITZGERALD SHORT TERM...FITZGERALD LONG TERM...FITZGERALD/MARTIN AVIATION...DEVOIR/CERU
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
449 AM EST MON DEC 7 2015 .SYNOPSIS... A MOISTURE-STARVED SOUTHERN STREAM SHORTWAVE WILL TRACK ACROSS SOUTHERN PA LATE TODAY. A SERIES OF LOW PRES SYSTEMS WILL TRACK WELL WEST OF PA LATE IN THE WEEK...AS AN ANOMALOUS UPPER RIDGE BUILDS ALONG THE EAST COAST. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 11-3.9U LOOP AT 0830Z SHOWING AREAS OF DENSE VALLEY FROM EXTENDING FROM THE CENTRAL MTNS EASTWARD INTO THE SUSQ VALLEY. STRONG INVERSION AND LOW DECEMBER SUN ANGLE WILL ALLOW FOG TO PERSIST THROUGH LATE AM...COVERED BY DENSE FOG ADV THRU 16Z. APPROACHING UPPER LOW IS PRODUCING A BATCH OF SHOWERS ACROSS THE OHIO VALLEY AT 09Z. HOWEVER...ALL NEAR TERM MDL GUIDANCE TRACKS WEAKENING SFC LOW WELL SOUTH OF PA...WITH AIR MASS OVR PA REMAINING TOO DRY TO SUPPORT PRECIP. THEREFORE...WILL CONTINUE TO CARRY ONLY A SLIGHT CHC OF SHOWERS ACROSS SOMERSET/BEDFORD COUNTIES LATER TODAY. UPSTREAM SATL IMAGERY AND MDL RH FIELDS SUGGEST PATCHY AM FOG WILL GIVE WAY TO MSUNNY SKIES ACROSS MOST OF CENTRAL PA. EXCEPTION WILL BE SOMERSET/BEDFORD COS...WHERE INCREASING CLOUDS EXPECTED THIS AFTN. HIGHS WILL BE FAIRLY UNIFORM...RANGING FROM 45-50F OVER MOST OF THE REGION. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/... UPPER LOW WILL PUSH EAST OF PA TONIGHT...AS SFC RIDGE BUILDS IN FROM THE NORTHWEST. MCLEAR SKIES AND A NEARLY CALM WIND SHOULD ONCE AGAIN PROMOTE AREAS OF LOW CLOUDS/FOG. WEAKEST GRADIENT AND REGION MOST FAVORABLE FOR FOG WILL BE ACROSS THE ALLEGHENY PLATEAU WITH ONLY PATCHY FOG LIKELY FURTHER EAST ACROSS THE SUSQ VALLEY. SFC RIDGE OVR THE REGION SHOULD ENSURE A DRY TUESDAY WITH PASSING UPPER LVL SHORTWAVE LIKELY TO PRODUCE NO MORE THAN SCT MID/HIGH LVL CLOUDINESS. SUPERBLEND AND NEW ECME MOS INDICATE HIGHS IN THE 40S. && .LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... THE MAIN FORECAST STORY THRU THE END OF THIS WEEK IS THE CONTINUED MILD TEMPERATURES...AS ZONAL FLOW FLOODS THE CONUS WITH PACIFIC AIR. NAEFS AND ECENS OUTPUT SHOWING A SERIES OF SFC LOWS TRACKING NORTHWARD THRU THE GRT LKS LATE NEXT WEEK...AS ANOMALOUS UPPER RIDGE BUILDS ALONG THE E COAST. HAVE INCLUDED A CHC OF SHRA ASSOC WITH SHORTWAVE LIFTING UP THE OHIO VALLEY LATE WED/EARLY THU. OTHERWISE...THE EXTENDED FCST APPEARS DRY AND INCREASINGLY WARM BENEATH BUILDING RIDGE. GEFS PLUME DATA AND ECEME MOS SUPPORT MIN TEMPS ABOVE FREEZING ACROSS THE ENTIRE CWA THU-SUN AND MAX TEMPS AT LEAST 15F ABV NORMAL. SOME CHC OF SHOWERS TOWARD THE END OF THE FCST PERIOD...AS SOUTHERN STREAM SHORTWAVE LIFTS THRU THE GRT LKS...PUSHING A COLD FRONT INTO PA. LATEST GEFS OUTPUT SUGGESTS FRONT AND SHOWER THREAT COULD ARRIVE BY SUNDAY...WHILE ECENS IS A SLOWER SOLUTION WITH DRY/VERY WARM WX PERSISTING THRU SUNDAY. && .AVIATION /09Z MONDAY THROUGH FRIDAY/... THE BIGGEST FORECAST QUESTION OVERNIGHT IS FOG FORMATION. CURRENT HRRR AND RAP RUNS DECREASE THE FOG THROUGH MOST OF THE CENTRAL PA BY 09Z...HOWEVER GIVEN THE LOW DEWPOINT DEPRESSIONS...CALM WINDS AN STRONG INVERSION EXPECT CENTRAL TAF SITES AOO...UNV...IPT TO SEE IFR AND LOWER CIGS AND VSBYS OVERNIGHT UNTIL MORNING. THERE HAS BEEN SOME VARIABILITY IN VSBYS DUE TO THE FOG MOVEMENT. EXPECT TEMPO GROUPS OF 1/4 MILE AT TIMES AT UNV AND AOO...AND MVFR RESTRICTIONS DUE TO THE PATCHY NATURE OF THE FORMING FOG THROUGH THE FIRST HALF OF THE OVERNIGHT HOURS. AS THE FOG/MIST BECOMES ENTRENCHED BETWEEN 06Z TO 09Z...VSBYS WILL DECREASE AND REMAIN IFR AND LOWER. MAINLY VFR CONDS WILL PREVAIL AT JST AND BFD...DUE TO THE DRY NW FLOW ALOFT. FOG/MIST THROUGH THE LOWER SUSQ IS AN INTERESTING CONUNDRUM. THOUGH SOME HIGH CLOUDS PERSIST...CALMING WINDS...DEWPOINT DEPRESSIONS OF CURRENT 4 DEGREES OR LESS...SHOULD ALLOW FOR FOR DENSE FOG OVERNIGHT. EXPECT PERIODS OF IFR VSBYS AND LOWER ESPECIALLY NEAR SUNRISE. THE FOG WILL SLOWLY LIFT/DISSIPATE TOMORROW MORNING...THOUGH QUICKER THAN IT DID ON SUNDAY. SO EXPECT VFR TO RETURN BY 15Z MON AT ALL SITES. A MOISTURE-STARVED SOUTHERN STREAM SHORTWAVE WILL TRACK ACROSS THE AREA MONDAY...POTENTIALLY BRINGING RESTRICTIONS TO KJST LATER MONDAY AND SPREADING INTO MAINLY THE SOUTHERN HALF OF THE STATE MON NIGHT. OUTLOOK... MON-MON NIGHT...CHANCE FOR MVFR CONDITIONS IN -SHRA ACROSS THE SOUTHERN HALF OF PENN. TUE...NO SIG WX EXPECTED. TUE NIGHT-WED NIGHT...CHANCE FOR MVFR CIGS. THU-FRI...MVFR POSS NW. && .CTP WATCHES/WARNINGS/ADVISORIES... DENSE FOG ADVISORY UNTIL 11 AM EST THIS MORNING FOR PAZ012- 017>019-025>028-034>036-041-045-046-049>053-056>059-063>066. && $$ SYNOPSIS...FITZGERALD NEAR TERM...FITZGERALD SHORT TERM...FITZGERALD LONG TERM...FITZGERALD/MARTIN AVIATION...DEVOIR/CERU
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
117 AM EST MON DEC 7 2015 .SYNOPSIS... AN UPPER LEVEL LOW DROPPING SE FROM THE OHIO VLY MAY BRING A FEW SHOWERS TO SOUTHERN PA ON MONDAY. ANOTHER UPPER LEVEL LOW MOVING ACROSS THE GREAT LAKES ON WED MAY BRING A FEW MORE SHOWERS TO THE AREA LATER WED INTO THU. OTHERWISE HIGH PRESSURE OVER THE SE STATES WILL KEEP DRY AND MILD CONDITIONS ACROSS THE KEYSTONE STATE THIS WEEK. HIGH TEMPERATURES WILL AVERAGE WELL ABOVE NORMAL FOR EARLY DEC. && .NEAR TERM /UNTIL 10 AM THIS MORNING/... SFC OBS AT 06Z INDICATING PATCHY DENSE FOG FROM THE CENTRAL MTNS EASTWARD. VEIL OF HIGH CLOUDS SHOULD BE SHIFTING EAST OF THE AREA BTWN 07Z-09Z...LEADING TO ADDITIONAL RAD COOLING AND MORE EXTENSIVE FOG TOWARDS DAWN. NO CHANGES EXPECTED TO CURRENT DENSE FOG ADVISORY...WHICH COVERS ALL BUT THE N MTNS AND LAUREL HIGHLANDS. DWPT DEPRESSIONS ALREADY QUITE LOW...SO EXPECT ONLY ANOTHER COUPLE DEG DROP IN TEMPS BTWN 06Z-12Z WITH MINS OF 25-30F OVER MOST OF CENTRAL PA. && .SHORT TERM /10 AM THIS MORNING THROUGH 6 PM TUESDAY/... MOISTURE CHALLENGED UPPER TROF CRASHING INTO AND DISPLACING THE EAST COAST UPPER RIDGE WILL MOVE OVER WESTERN AND CENTRAL PA ON MONDAY...BRINGING CONSIDERABLE CLOUDINESS ACROSS SW PA BUT LITTLE ELSE IN THE WAY OF SENSIBLE WEATHER AFTER ANOTHER ROUND OF MORNING VALLEY FOG. THINK THE ONLY AREA TO SEE SHOWERS FROM THIS SYSTEM WILL BE THE LAUREL HIGHLANDS...AS BOUNDARY LAYER IS JUST TOO DRY TO SUPPORT MUCH PRECIPITATION FARTHER EAST. CLOUDS WILL BE THICKEST OVER THE LAUREL HIGHLANDS AS WELL...WITH MOSTLY CLOUDY SKIES SEEN THERE... WHILE THE REMAINDER OF CENTRAL PA RANGES FROM P/S TO M/S. HIGHS WILL BE FAIRLY UNIFORM...RANGING FROM THE UPPER 40S TO THE LOWER 50S. && .LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... THE MAIN FORECAST STORY FOR THE EXTENDED PERIOD IS THE CONTINUED MILD TEMPERATURES...AS ZONAL FLOW FLOODS THE CONUS WITH PACIFIC AIR. NAEFS AND ECENS OUTPUT SHOWING A SERIES OF SFC LOWS TRACKING NORTHWARD THRU THE GRT LKS LATE NEXT WEEK...AS ANOMALOUS UPPER RIDGE BUILDS ALONG THE E COAST. HAVE INCLUDED A CHC OF SHRA ASSOC WITH SHORTWAVE LIFTING UP THE OHIO VALLEY LATE WED/EARLY THU. OTHERWISE...THE EXTENDED FCST APPEARS DRY AND INCREASINGLY WARM BENEATH BUILDING RIDGE. GEFS PLUME DATA AND ECEME MOS SUPPORT MIN TEMPS ABOVE FREEZING ACROSS THE ENTIRE CWA THU-SAT AND MAX TEMPS AT LEAST 15F ABV NORMAL. MAIN CHANGE WAS TO EDGE TEMPS UP A LITTLE. ALSO MORE FOG COULD FORM TUESDAY MORNING...AS SKIES CLEAR. THUS I ADDED PATCHY FOG. ICE FOG ON A LOT OF OBJECTS EARLY TODAY. A BIG CHANGE FROM THE LAST 2 WINTERS...ENJOY THE GOOD WEATHER WHILE IT LAST. FOR NEXT WEEKEND...STILL MILD...BUT SOME CHC OF SHOWERS BY SUNDAY. WENT WITH CHC POPS FOR NOW. && .AVIATION /06Z MONDAY THROUGH FRIDAY/... THE BIGGEST FORECAST QUESTION OVERNIGHT IS FOG FORMATION. CURRENT HRRR AND RAP RUNS DECREASE THE FOG THROUGH MOST OF THE CENTRAL PA BY 09Z...HOWEVER GIVEN THE LOW DEWPOINT DEPRESSIONS...CALM WINDS AN STRONG INVERSION EXPECT CENTRAL TAF SITES AOO...UNV...IPT TO SEE IFR AND LOWER CIGS AND VSBYS OVERNIGHT UNTIL MORNING. THERE HAS BEEN SOME VARIABILITY IN VSBYS DUE TO THE FOG MOVEMENT. EXPECT TEMPO GROUPS OF 1/4 MILE AT TIMES AT UNV AND AOO...AND MVFR RESTRICTIONS DUE TO THE PATCHY NATURE OF THE FORMING FOG THROUGH THE FIRST HALF OF THE OVERNIGHT HOURS. AS THE FOG/MIST BECOMES ENTRENCHED BETWEEN 06Z TO 09Z...VSBYS WILL DECREASE AND REMAIN IFR AND LOWER. MAINLY VFR CONDS WILL PREVAIL AT JST AND BFD...DUE TO THE DRY NW FLOW ALOFT. FOG/MIST THROUGH THE LOWER SUSQ IS AN INTERESTING CONUNDRUM. THOUGH SOME HIGH CLOUDS PERSIST...CALMING WINDS...DEWPOINT DEPRESSIONS OF CURRENT 4 DEGREES OR LESS...SHOULD ALLOW FOR FOR DENSE FOG OVERNIGHT. EXPECT PERIODS OF IFR VSBYS AND LOWER ESPECIALLY NEAR SUNRISE. THE FOG WILL SLOWLY LIFT/DISSIPATE TOMORROW MORNING...THOUGH QUICKER THAN IT DID ON SUNDAY. SO EXPECT VFR TO RETURN BY 15Z MON AT ALL SITES. A MOISTURE-STARVED SOUTHERN STREAM SHORTWAVE WILL TRACK ACROSS THE AREA MONDAY...POTENTIALLY BRINGING RESTRICTIONS TO KJST LATER MONDAY AND SPREADING INTO MAINLY THE SOUTHERN HALF OF THE STATE MON NIGHT. OUTLOOK... MON-MON NIGHT...CHANCE FOR MVFR CONDITIONS IN -SHRA ACROSS THE SOUTHERN HALF OF PENN. TUE...NO SIG WX EXPECTED. TUE NIGHT-WED NIGHT...CHANCE FOR MVFR CIGS. THU-FRI...MVFR POSS NW. && .CTP WATCHES/WARNINGS/ADVISORIES... DENSE FOG ADVISORY UNTIL 11 AM EST THIS MORNING FOR PAZ012- 017>019-025>028-034>036-041-045-046-049>053-056>059-063>066. && $$ SYNOPSIS...MARTIN NEAR TERM...FITZGERALD SHORT TERM...DEVOIR/FITZGERALD LONG TERM...FITZGERALD/MARTIN AVIATION...DEVOIR/CERU
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1147 PM EST SUN DEC 6 2015 .SYNOPSIS... AN UPPER LEVEL LOW DROPPING SE FROM THE OHIO VLY MAY BRING A FEW SHOWERS TO SOUTHERN PA ON MONDAY. ANOTHER UPPER LEVEL LOW MOVING ACROSS THE GREAT LAKES ON WED MAY BRING A FEW MORE SHOWERS TO THE AREA LATER WED INTO THU. OTHERWISE HIGH PRESSURE OVER THE SE STATES WILL KEEP DRY AND MILD CONDITIONS ACROSS THE KEYSTONE STATE THIS WEEK. HIGH TEMPERATURES WILL AVERAGE WELL ABOVE NORMAL FOR EARLY DEC. && .NEAR TERM /UNTIL 10 AM MONDAY MORNING/... 10 PM UPDATE... FOG IS FORMING AS FCST. IT IS DENSE IN THE ADVY AREA ALREADY AND MAY EXPAND. BUT WILL WAIT A BIT LONGER TO DECIDE IF THE NOT- ADVISED AREAS WILL NEED ONE AS WELL. TEMPS ARE ABOVE FREEZING IN THE LAURELS AND IN KBFD. UPDATE: I DUG DEEPER AND DISCOVERED THAT CTP CAN INDEED ISSUE A FREEZING FOG ADVY. HOWEVER...THE THREAT OF DENSE FOG IS CORRECT AND I AM HITTING THE ICE THREAT HARD IN THE TEXT AND SOCIAL MEDIA. TO KEEP CONFUSION TO A MINIMUM...WILL JUST KEEP IT AS A DENSE FOG ADVY. IF THIS RECURRS TOMORROW NIGHT...WILL ASSESS THE THREATS AND APPROPRIATE PRODUCTS/WORDING THEN. 7 PM UPDATE... TWO CALLS NOW THAT INDICATE DENSE FOG IN LOW LYING AREAS OF HAPPY VALLEY. AOO AND A FEW OTHER SITES HAVE ALSO SHOWN HINTS AT GOING LOW ON THE VISBY. AT THIS POINT...ONLY KFIG IS AT 1/4SM...NONE ARE BELOW THAT. HOWEVER...DEWPOINT DEPRESSIONS ARE ONLY 1-2F AT MANY SITES. WILL GO AHEAD AND ISSUE A DENSE FOG ADVY FOR THE CENTRAL COUNTIES...STARTING SMALL. CONFIDENCE IS STILL LOWER THAN NECESSARY - BUT ALMOST THERE - THAT WE WOULD NEED THE SAME OVER THE AREAS WHICH DRIED OUT BETTER/LONGER DURING THE DAY TODAY. WILL START WITH THE PLACES THAT DID NOT CLEAR OR CLEARED FOR ONLY A SHORT TIME. 5 PM UPDATE... FOG AND STRATUS NEVER LEFT THE MID SUSQ AND LIKELY WILL NOT GO AWAY IN THE NEXT 18HRS. VISBY OUT THE WINDOW AT LAST DAYLIGHT IS ABOUT 3SM IN A THICK HAZE AND KUNV ONLY 1-2SM AWAY IS ONLY 1/8SM - ACTUAL OBSERVER AT TOWER. FOG IS STARTING TO SHOW UP AGAIN IN THE OBS AT MANY OF THE SITES WHICH DID CLEAR UP EARLIER TODAY. BUT...LOOKS LIKE IT IS ALMOST CERTAIN THAT IT WILL RE-ESTABLISH TONIGHT. THE HIGH CLOUDS SHOULD NOT SERIOUSLY AFFECT THE BLYR...BUT THAT IS THE ONLY FACTOR IN THE MIX WHICH COULD BUST A FOGGY FORECAST - IF IT STAYS MILDER. MAY NEED TO HOIST THE DENSE FOG ADVY IN JUST A SHORT WHILE. WAITING FOR JUST A FEW MORE OBS TO BE A LITTLE MORE CERTAIN. AGAIN...THE THREAT WILL PROBABLY BE A COMBINATION OF REDUCED VISBY AND THE PRESENCE OF FREEZING FOG AND POSSIBILITY OF AN ICY COATING. NOT REALLY A PRODUCT AVAILABLE TO CENTRAL PA TO COVER THIS. SO WE CAN BASICALLY TRY TWO ROUTES- EITHER USE A WINTER WX ADVY OR...LIKE WE HAD EARLIER...THE DENSE FOG ADVY WITH LOTS OF ICY WORDS IN IT. TO KEEP IT CONSISTENT AND ACCOUNT FOR THE FACT THAT THE ROADS MAY NOT BECOME ICY EVERYWHERE...A DENSE FOG ADVY IS PROBABLY THE ROUTE TO CHOOSE SHOULD WE NEED IT AGAIN. PREV... EXTREMELY STUBBORN FOG CONTINUES TO SLOWLY LIFT AND DISSIPATE OVER THE CENTRAL MOUNTAIN VALLEYS EARLY THIS AFTERNOON. WARM ADVECTION OVER THE COLD VALLEYS WHICH RADIATED EFFICIENTLY OVERNIGHT LED TO SOME OF THE MOST PERSISTENT ICE FOG I`VE SEEN IN CENTRAL PA IN THE PAST 15 YEARS. WHERE IT REMAINED FOGGY...TEMPERATURES REMAINED BELOW FREEZING THIS MORNING...WHILE CLEAR AREAS WARMED THROUGH THE 40S AND IN SOME CASES INTO THE LOWER 50S (SOUTH CENTRAL MOUNTAINS). AS THE UPPER RIDGE AXIS BREAKS DOWN/ SWINGS EAST OF THE REGION LATE TODAY AND TONIGHT...THIN CIRRUS WILL CONTINUE TO OVERSPREAD THE EASTERN HALF OF CENTRAL PA...AS IT HAS OVER THE WEST. SFC HIGH WEAKENS AND SHIFTS EAST OF PA TONIGHT...BUT IT REMAINS FAVORABLE FOR PATCHY LATE NIGHT VALLEY FOG. MINS WILL BE MOSTLY IN THE MID TO UPPER 20S ONCE AGAIN. && .SHORT TERM /10 AM MONDAY MORNING THROUGH 6 PM MONDAY/... MOISTURE CHALLENGED UPPER TROF CRASHING INTO AND DISPLACING THE EAST COAST UPPER RIDGE WILL MOVE OVER WESTERN AND CENTRAL PA ON MONDAY...BRINGING CONSIDERABLE CLOUDINESS BUT LITTLE ELSE IN THE WAY OF SENSIBLE WEATHER AFTER ANOTHER ROUND OF MORNING VALLEY FOG. THINK THE ONLY AREA TO SEE SHOWERS FROM THIS SYSTEM WILL BE THE LAUREL HIGHLANDS...AS BOUNDARY LAYER IS JUST TOO DRY TO SUPPORT MUCH PRECIPITATION FARTHER EAST. CLOUDS WILL BE THICKEST OVER THE LAUREL HIGHLANDS AS WELL...WITH MOSTLY CLOUDY SKIES SEEN THERE... WHILE THE REMAINDER OF CENTRAL PA RANGES FROM P/S TO M/S. HIGHS WILL BE FAIRLY UNIFORM...RANGING FROM THE UPPER 40S TO THE LOWER 50S. && .LONG TERM /MONDAY NIGHT THROUGH SUNDAY/... THE MAIN FORECAST STORY FOR THE EXTENDED PERIOD IS THE CONTINUED MILD TEMPERATURES...AS ZONAL FLOW FLOODS THE CONUS WITH PACIFIC AIR. NAEFS AND ECENS OUTPUT SHOWING A SERIES OF SFC LOWS TRACKING NORTHWARD THRU THE GRT LKS LATE NEXT WEEK...AS ANOMALOUS UPPER RIDGE BUILDS ALONG THE E COAST. HAVE INCLUDED A CHC OF SHRA ASSOC WITH SHORTWAVE LIFTING UP THE OHIO VALLEY LATE WED/EARLY THU. OTHERWISE...THE EXTENDED FCST APPEARS DRY AND INCREASINGLY WARM BENEATH BUILDING RIDGE. GEFS PLUME DATA AND ECEME MOS SUPPORT MIN TEMPS ABOVE FREEZING ACROSS THE ENTIRE CWA THU-SAT AND MAX TEMPS AT LEAST 15F ABV NORMAL. MAIN CHANGE WAS TO EDGE TEMPS UP A LITTLE. ALSO MORE FOG COULD FORM TUESDAY MORNING...AS SKIES CLEAR. THUS I ADDED PATCHY FOG. ICE FOG ON A LOT OF OBJECTS EARLY TODAY. A BIG CHANGE FROM THE LAST 2 WINTERS...ENJOY THE GOOD WEATHER WHILE IT LAST. FOR NEXT WEEKEND...STILL MILD...BUT SOME CHC OF SHOWERS BY SUNDAY. WENT WITH CHC POPS FOR NOW. && .AVIATION /06Z MONDAY THROUGH FRIDAY/... THE BIGGEST FORECAST QUESTION OVERNIGHT IS FOG FORMATION. CURRENT HRRR AND RAP RUNS DECREASE THE FOG THROUGH MOST OF THE CENTRAL PA BY 09Z...HOWEVER GIVEN THE LOW DEWPOINT DEPRESSIONS...CALM WINDS AN STRONG INVERSION EXPECT CENTRAL TAF SITES AOO...UNV...IPT TO SEE IFR AND LOWER CIGS AND VSBYS OVERNIGHT UNTIL MORNING. THERE HAS BEEN SOME VARIABILITY IN VSBYS DUE TO THE FOG MOVEMENT. EXPECT TEMPO GROUPS OF 1/4 MILE AT TIMES AT UNV AND AOO...AND MVFR RESTRICTIONS DUE TO THE PATCHY NATURE OF THE FORMING FOG THROUGH THE FIRST HALF OF THE OVERNIGHT HOURS. AS THE FOG/MIST BECOMES ENTRENCHED BETWEEN 06Z TO 09Z...VSBYS WILL DECREASE AND REMAIN IFR AND LOWER. MAINLY VFR CONDS WILL PREVAIL AT JST AND BFD...DUE TO THE DRY NW FLOW ALOFT. FOG/MIST THROUGH THE LOWER SUSQ IS AN INTERESTING CONUNDRUM. THOUGH SOME HIGH CLOUDS PERSIST...CALMING WINDS...DEWPOINT DEPRESSIONS OF CURRENT 4 DEGREES OR LESS...SHOULD ALLOW FOR FOR DENSE FOG OVERNIGHT. EXPECT PERIODS OF IFR VSBYS AND LOWER ESPECIALLY NEAR SUNRISE. THE FOG WILL SLOWLY LIFT/DISSIPATE TOMORROW MORNING...THOUGH QUICKER THAN IT DID ON SUNDAY. SO EXPECT VFR TO RETURN BY 15Z MON AT ALL SITES. A MOISTURE-STARVED SOUTHERN STREAM SHORTWAVE WILL TRACK ACROSS THE AREA MONDAY...POTENTIALLY BRINGING RESTRICTIONS TO KJST LATER MONDAY AND SPREADING INTO MAINLY THE SOUTHERN HALF OF THE STATE MON NIGHT. OUTLOOK... MON-MON NIGHT...CHANCE FOR MVFR CONDITIONS IN -SHRA ACROSS THE SOUTHERN HALF OF PENN. TUE...NO SIG WX EXPECTED. TUE NIGHT-WED NIGHT...CHANCE FOR MVFR CIGS. THU-FRI...MVFR POSS NW. && .CTP WATCHES/WARNINGS/ADVISORIES... DENSE FOG ADVISORY UNTIL 11 AM EST MONDAY FOR PAZ012-017>019- 025>028-034>036-041-045-046-049>053-056>059-063>066. && $$ SYNOPSIS...MARTIN NEAR TERM...DANGELO/DEVOIR SHORT TERM...DEVOIR LONG TERM...FITZGERALD/MARTIN AVIATION...DEVOIR/CERU
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
ISSUED BY NATIONAL WEATHER SERVICE BROWNSVILLE TX 1055 AM CST MON DEC 7 2015 .AVIATION...FOR THE 18Z TAFS... VFR THROUGH THE PERIOD. SFC HIGH PRESSURE WILL REMAIN ENTRENCHED ACROSS THE HILL COUNTRY AND SOUTH TEXAS THROUGH THIS EVENING THEN SPREAD EASTWARD INTO THE NORTHERN GULF COAST TUESDAY. A SFC TROUGH WILL DEVELOP ACROSS THE HIGH PLAINS OF WEST TEXAS IN RESPONSE TO A MID LEVEL DISTURBANCE MOVING ACROSS THE CENTRAL PLAINS TUESDAY. THIS TROUGH WILL HELP ESTABLISH WINDS FROM THE SSW BY NOON TUESDAY. A FEW HIGH CLOUDS EXPECTED TO MOVE ACROSS THE AERODROMES BEGINNING THIS EVENING BUT NO BREAKS IN CATEGORY EXPECTED. && .PREV DISCUSSION... /ISSUED 540 AM CST MON DEC 7 2015/ AVIATION... /12Z TAFS/ VFR CONDITIONS ARE EXPECTED ACROSS AREA SITES THROUGH THE FORECAST PERIOD. LIGHT AND VARIABLE WINDS WILL PERSIST ACROSS THE AREA TERMINALS THROUGH TUESDAY. PREV DISCUSSION... /ISSUED 400 AM CST MON DEC 7 2015/ SHORT TERM (TODAY THROUGH TUESDAY)... ONE LAST COOL MORNING TODAY WITH A WARMING TREND BEGINNING AND LASTING INTO AT LEAST FRIDAY. IT WILL BE A STRAIGHT TEMPERATURE FORECAST AS NO PRECIPITATION IS EXPECTED IN THE SHORT AND MOSTLY LONG TERM PERIODS. WATER VAPOR AND RAP ANALYSIS DEPICTS AN EXITING TROUGH AXIS ACROSS THE MID-MISSISSIPPI RIVER VALLEY WITH MID-LVL NORTHWEST FLOW OVER TOP SURFACE HIGH PRESSURE CENTERED OVER THE LONE STATE STATE. CLEAR SKIES ARE EXPECTED TODAY AND TOMORROW THAT...ALONG WITH A SLOWLY MODIFYING AIRMASS...WITH PROMOTE A WARMING TREND THAT WILL CONTINUE INTO MID AND LATE WEEK. MAX HIGHS TODAY SHOULD BE QUITE SIMILAR TO YESTERDAY TO 1F DEGREE COOLER GIVEN THE SLIGHTLY LOWER MIXING HEIGHTS. THE RESULTANT TEMPERATURES SUPPORTED BY THE GFS/NAM SOUNDINGS FALL MUCH MORE IN LINE WITH THE MAVMOS VALUES WITH SOME SLIGHT +1F DEGREE TWEAKS MADE GIVEN PAST TRENDS. MIXING HEIGHTS WILL INCREASE TUESDAY WITH WARMER 925MB HEIGHTS THAT WILL SUPPORT AN ADDITIONAL 2-4F DEGREES OVER TODAY`S HIGHS. MORNING LOWS WILL NOT BE AS COOL TUESDAY VS. THIS MORNING AS WEAK SOUTH WINDS SLOWLY INCREASE DEWPOINT VALUES. LONG TERM (WEDNESDAY THROUGH SUNDAY)... WELL ABOVE NORMAL TEMPERATURES ARE EXPECTED MID TO LATE WEEK AS READINGS WILL LIKELY REACH INTO THE UPPER 70S AND LOW TO EVEN MID 80S ACROSS THE REGION. RAIN CHANCES WILL INCREASE AHEAD OF A FRONT THAT COULD MOVE THROUGH LATE SATURDAY INTO SUNDAY. A SUBTROPICAL SURFACE HIGH WILL BECOME ESTABLISHED OVER THE GULF AND EXTEND TOWARDS SOUTH-CENTRAL TEXAS THROUGH MID TO LATE-WEEK. THIS FEATURE...AND WITH THE MAIN JET STREAM WELL NORTH...WILL CONTINUE TO FOSTER LOW-LVL WARMING WITH SOUTHWEST AND WEST FLOW IN THE 925-700MB LAYER. THIS PATTERN IS ONE THAT ALLOWS HIGHER TEMPERATURES TO BE ACHIEVED...ESPECIALLY GIVEN THE ADVERTISED WELL MIXED PBL TRANSLATING THE COMPRESSIONALLY WARMED AIR DOWN TO THE SURFACE. READINGS BY THURSDAY AND ESPECIALLY INTO FRIDAY WILL BE 7-15F DEGREES ABOVE NORMAL WITH RIO GRANDE LOCATIONS PUSHING INTO THE MID TO UPPER 80S. KSAT WILL APPROACH 80F THURSDAY AND LIKELY SURPASS 80F FRIDAY WITH KAUS COMING QUITE CLOSE AS WELL. FRIDAY WILL ALSO BE QUITE BREEZY /20MPH WINDS & GUSTS TO 30MPH/ AHEAD OF A DEVELOPING SYSTEM FARTHER WEST OVER THE FOUR CORNER REGION. BOTH ECMWF AND GFS LONGER RANGE MOS VALUES ARE IN GOOD AGREEMENT OF THESE VALUES WITH BUFR SOUNDINGS CONFIRMING THE STRONG LIKELIHOOD OF WELL ABOVE NORMAL TEMPERATURES. MORNINGS LOWS WILL SLOWLY COME UP AS WELL AS DEWPOINTS SLOWLY CLIMB THROUGH SATURDAY. BY LATE WEEK AND OVER THE WEEKEND...A STRONG H5 TROUGH WILL DIG ACROSS THE WESTERN BASIN. GFS AND EC DIVERGE ON THIS SYSTEM`S PROGRESSIVENESS. OPERATIONAL GFS IS QUICKER TO MOVE IT THROUGH VS. ECMWF THAT LAGS THE ENERGY BACK WEST. GFS ENSEMBLES SUGGEST A SLIGHTLY LESS PROGRESSIVE SYSTEM VS. THE OPERATIONAL GFS RUN AND HAVE WEIGHTED SATURDAY/SUNDAY TEMPS AND POPS MORE TOWARDS THE ENSEMBLE MEAN. A COLD FRONT SHOULD MOVE THROUGH SOMETIME LATE SATURDAY OR LATE SUNDAY. WILL NEED TO FINE TUNE THIS SECTION AS SOLUTIONS CONVERGE ON BETTER SYSTEM TIMING. && .PRELIMINARY POINT TEMPS/POPS... AUSTIN CAMP MABRY 70 46 73 49 76 / 0 0 0 0 - AUSTIN BERGSTROM INTL AIRPORT 69 42 73 47 75 / 0 0 0 0 - NEW BRAUNFELS MUNI AIRPORT 69 44 74 49 76 / 0 0 0 0 - BURNET MUNI AIRPORT 67 43 73 46 74 / 0 0 0 0 0 DEL RIO INTL AIRPORT 71 44 74 47 76 / 0 0 0 0 0 GEORGETOWN MUNI AIRPORT 66 42 74 47 74 / 0 0 0 0 - HONDO MUNI AIRPORT 69 43 74 47 76 / 0 0 0 0 0 SAN MARCOS MUNI AIRPORT 67 44 73 48 75 / 0 0 0 0 - LA GRANGE - FAYETTE REGIONAL 68 46 73 50 75 / 0 0 0 0 - SAN ANTONIO INTL AIRPORT 71 46 75 50 75 / 0 0 0 0 0 STINSON MUNI AIRPORT 70 46 75 50 76 / 0 0 0 0 0 && .EWX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ AVIATION...SCHOLL
AREA FORECAST DISCUSSION...UPDATED
NWS AUSTIN/SAN ANTONIO TX
540 AM CST MON DEC 7 2015 .AVIATION... /12Z TAFS/ VFR CONDITIONS ARE EXPECTED ACROSS AREA SITES THROUGH THE FORECAST PERIOD. LIGHT AND VARIABLE WINDS WILL PERSIST ACROSS THE AREA TERMINALS THROUGH TUESDAY. && .PREV DISCUSSION... /ISSUED 400 AM CST MON DEC 7 2015/ SHORT TERM (TODAY THROUGH TUESDAY)... ONE LAST COOL MORNING TODAY WITH A WARMING TREND BEGINNING AND LASTING INTO AT LEAST FRIDAY. IT WILL BE A STRAIGHT TEMPERATURE FORECAST AS NO PRECIPITATION IS EXPECTED IN THE SHORT AND MOSTLY LONG TERM PERIODS. WATER VAPOR AND RAP ANALYSIS DEPICTS AN EXITING TROUGH AXIS ACROSS THE MID-MISSISSIPPI RIVER VALLEY WITH MID-LVL NORTHWEST FLOW OVER TOP SURFACE HIGH PRESSURE CENTERED OVER THE LONE STATE STATE. CLEAR SKIES ARE EXPECTED TODAY AND TOMORROW THAT...ALONG WITH A SLOWLY MODIFYING AIRMASS...WITH PROMOTE A WARMING TREND THAT WILL CONTINUE INTO MID AND LATE WEEK. MAX HIGHS TODAY SHOULD BE QUITE SIMILAR TO YESTERDAY TO 1F DEGREE COOLER GIVEN THE SLIGHTLY LOWER MIXING HEIGHTS. THE RESULTANT TEMPERATURES SUPPORTED BY THE GFS/NAM SOUNDINGS FALL MUCH MORE IN LINE WITH THE MAVMOS VALUES WITH SOME SLIGHT +1F DEGREE TWEAKS MADE GIVEN PAST TRENDS. MIXING HEIGHTS WILL INCREASE TUESDAY WITH WARMER 925MB HEIGHTS THAT WILL SUPPORT AN ADDITIONAL 2-4F DEGREES OVER TODAY`S HIGHS. MORNING LOWS WILL NOT BE AS COOL TUESDAY VS. THIS MORNING AS WEAK SOUTH WINDS SLOWLY INCREASE DEWPOINT VALUES. LONG TERM (WEDNESDAY THROUGH SUNDAY)... WELL ABOVE NORMAL TEMPERATURES ARE EXPECTED MID TO LATE WEEK AS READINGS WILL LIKELY REACH INTO THE UPPER 70S AND LOW TO EVEN MID 80S ACROSS THE REGION. RAIN CHANCES WILL INCREASE AHEAD OF A FRONT THAT COULD MOVE THROUGH LATE SATURDAY INTO SUNDAY. A SUBTROPICAL SURFACE HIGH WILL BECOME ESTABLISHED OVER THE GULF AND EXTEND TOWARDS SOUTH-CENTRAL TEXAS THROUGH MID TO LATE-WEEK. THIS FEATURE...AND WITH THE MAIN JET STREAM WELL NORTH...WILL CONTINUE TO FOSTER LOW-LVL WARMING WITH SOUTHWEST AND WEST FLOW IN THE 925-700MB LAYER. THIS PATTERN IS ONE THAT ALLOWS HIGHER TEMPERATURES TO BE ACHIEVED...ESPECIALLY GIVEN THE ADVERTISED WELL MIXED PBL TRANSLATING THE COMPRESSIONALLY WARMED AIR DOWN TO THE SURFACE. READINGS BY THURSDAY AND ESPECIALLY INTO FRIDAY WILL BE 7-15F DEGREES ABOVE NORMAL WITH RIO GRANDE LOCATIONS PUSHING INTO THE MID TO UPPER 80S. KSAT WILL APPROACH 80F THURSDAY AND LIKELY SURPASS 80F FRIDAY WITH KAUS COMING QUITE CLOSE AS WELL. FRIDAY WILL ALSO BE QUITE BREEZY /20MPH WINDS & GUSTS TO 30MPH/ AHEAD OF A DEVELOPING SYSTEM FARTHER WEST OVER THE FOUR CORNER REGION. BOTH ECMWF AND GFS LONGER RANGE MOS VALUES ARE IN GOOD AGREEMENT OF THESE VALUES WITH BUFR SOUNDINGS CONFIRMING THE STRONG LIKELIHOOD OF WELL ABOVE NORMAL TEMPERATURES. MORNINGS LOWS WILL SLOWLY COME UP AS WELL AS DEWPOINTS SLOWLY CLIMB THROUGH SATURDAY. BY LATE WEEK AND OVER THE WEEKEND...A STRONG H5 TROUGH WILL DIG ACROSS THE WESTERN BASIN. GFS AND EC DIVERGE ON THIS SYSTEM`S PROGRESSIVENESS. OPERATIONAL GFS IS QUICKER TO MOVE IT THROUGH VS. ECMWF THAT LAGS THE ENERGY BACK WEST. GFS ENSEMBLES SUGGEST A SLIGHTLY LESS PROGRESSIVE SYSTEM VS. THE OPERATIONAL GFS RUN AND HAVE WEIGHTED SATURDAY/SUNDAY TEMPS AND POPS MORE TOWARDS THE ENSEMBLE MEAN. A COLD FRONT SHOULD MOVE THROUGH SOMETIME LATE SATURDAY OR LATE SUNDAY. WILL NEED TO FINE TUNE THIS SECTION AS SOLUTIONS CONVERGE ON BETTER SYSTEM TIMING. && .PRELIMINARY POINT TEMPS/POPS... AUSTIN CAMP MABRY 70 46 73 49 76 / 0 0 0 0 - AUSTIN BERGSTROM INTL AIRPORT 69 42 73 47 75 / 0 0 0 0 - NEW BRAUNFELS MUNI AIRPORT 69 44 74 49 76 / 0 0 0 0 - BURNET MUNI AIRPORT 67 43 73 46 74 / 0 0 0 0 0 DEL RIO INTL AIRPORT 71 44 74 47 76 / 0 0 0 0 0 GEORGETOWN MUNI AIRPORT 66 42 74 47 74 / 0 0 0 0 - HONDO MUNI AIRPORT 69 43 74 47 76 / 0 0 0 0 0 SAN MARCOS MUNI AIRPORT 67 44 73 48 75 / 0 0 0 0 - LA GRANGE - FAYETTE REGIONAL 68 46 73 50 75 / 0 0 0 0 - SAN ANTONIO INTL AIRPORT 71 46 75 50 75 / 0 0 0 0 0 STINSON MUNI AIRPORT 70 46 75 50 76 / 0 0 0 0 0 && .EWX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ MESOSCALE/AVIATION...17 SYNOPTIC/GRIDS...ALLEN
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
400 AM CST MON DEC 7 2015 .SHORT TERM (TODAY THROUGH TUESDAY)... ONE LAST COOL MORNING TODAY WITH A WARMING TREND BEGINNING AND LASTING INTO AT LEAST FRIDAY. IT WILL BE A STRAIGHT TEMPERATURE FORECAST AS NO PRECIPITATION IS EXPECTED IN THE SHORT AND MOSTLY LONG TERM PERIODS. WATER VAPOR AND RAP ANALYSIS DEPICTS AN EXITING TROUGH AXIS ACROSS THE MID-MISSISSIPPI RIVER VALLEY WITH MID-LVL NORTHWEST FLOW OVER TOP SURFACE HIGH PRESSURE CENTERED OVER THE LONE STATE STATE. CLEAR SKIES ARE EXPECTED TODAY AND TOMORROW THAT...ALONG WITH A SLOWLY MODIFYING AIRMASS...WITH PROMOTE A WARMING TREND THAT WILL CONTINUE INTO MID AND LATE WEEK. MAX HIGHS TODAY SHOULD BE QUITE SIMILAR TO YESTERDAY TO 1F DEGREE COOLER GIVEN THE SLIGHTLY LOWER MIXING HEIGHTS. THE RESULTANT TEMPERATURES SUPPORTED BY THE GFS/NAM SOUNDINGS FALL MUCH MORE IN LINE WITH THE MAVMOS VALUES WITH SOME SLIGHT +1F DEGREE TWEAKS MADE GIVEN PAST TRENDS. MIXING HEIGHTS WILL INCREASE TUESDAY WITH WARMER 925MB HEIGHTS THAT WILL SUPPORT AN ADDITIONAL 2-4F DEGREES OVER TODAY`S HIGHS. MORNING LOWS WILL NOT BE AS COOL TUESDAY VS. THIS MORNING AS WEAK SOUTH WINDS SLOWLY INCREASE DEWPOINT VALUES. && .LONG TERM (WEDNESDAY THROUGH SUNDAY)... WELL ABOVE NORMAL TEMPERATURES ARE EXPECTED MID TO LATE WEEK AS READINGS WILL LIKELY REACH INTO THE UPPER 70S AND LOW TO EVEN MID 80S ACROSS THE REGION. RAIN CHANCES WILL INCREASE AHEAD OF A FRONT THAT COULD MOVE THROUGH LATE SATURDAY INTO SUNDAY. A SUBTROPICAL SURFACE HIGH WILL BECOME ESTABLISHED OVER THE GULF AND EXTEND TOWARDS SOUTH-CENTRAL TEXAS THROUGH MID TO LATE-WEEK. THIS FEATURE...AND WITH THE MAIN JET STREAM WELL NORTH...WILL CONTINUE TO FOSTER LOW-LVL WARMING WITH SOUTHWEST AND WEST FLOW IN THE 925-700MB LAYER. THIS PATTERN IS ONE THAT ALLOWS HIGHER TEMPERATURES TO BE ACHIEVED...ESPECIALLY GIVEN THE ADVERTISED WELL MIXED PBL TRANSLATING THE COMPRESSIONALLY WARMED AIR DOWN TO THE SURFACE. READINGS BY THURSDAY AND ESPECIALLY INTO FRIDAY WILL BE 7-15F DEGREES ABOVE NORMAL WITH RIO GRANDE LOCATIONS PUSHING INTO THE MID TO UPPER 80S. KSAT WILL APPROACH 80F THURSDAY AND LIKELY SURPASS 80F FRIDAY WITH KAUS COMING QUITE CLOSE AS WELL. FRIDAY WILL ALSO BE QUITE BREEZY /20MPH WINDS & GUSTS TO 30MPH/ AHEAD OF A DEVELOPING SYSTEM FARTHER WEST OVER THE FOUR CORNER REGION. BOTH ECMWF AND GFS LONGER RANGE MOS VALUES ARE IN GOOD AGREEMENT OF THESE VALUES WITH BUFR SOUNDINGS CONFIRMING THE STRONG LIKELIHOOD OF WELL ABOVE NORMAL TEMPERATURES. MORNINGS LOWS WILL SLOWLY COME UP AS WELL AS DEWPOINTS SLOWLY CLIMB THROUGH SATURDAY. BY LATE WEEK AND OVER THE WEEKEND...A STRONG H5 TROUGH WILL DIG ACROSS THE WESTERN BASIN. GFS AND EC DIVERGE ON THIS SYSTEM`S PROGRESSIVENESS. OPERATIONAL GFS IS QUICKER TO MOVE IT THROUGH VS. ECMWF THAT LAGS THE ENERGY BACK WEST. GFS ENSEMBLES SUGGEST A SLIGHTLY LESS PROGRESSIVE SYSTEM VS. THE OPERATIONAL GFS RUN AND HAVE WEIGHTED SATURDAY/SUNDAY TEMPS AND POPS MORE TOWARDS THE ENSEMBLE MEAN. A COLD FRONT SHOULD MOVE THROUGH SOMETIME LATE SATURDAY OR LATE SUNDAY. WILL NEED TO FINE TUNE THIS SECTION AS SOLUTIONS CONVERGE ON BETTER SYSTEM TIMING. && .PRELIMINARY POINT TEMPS/POPS... AUSTIN CAMP MABRY 70 46 73 49 76 / 0 0 0 0 - AUSTIN BERGSTROM INTL AIRPORT 69 42 73 47 75 / 0 0 0 0 - NEW BRAUNFELS MUNI AIRPORT 69 44 74 49 76 / 0 0 0 0 - BURNET MUNI AIRPORT 67 43 73 46 74 / 0 0 0 0 0 DEL RIO INTL AIRPORT 71 44 74 47 76 / 0 0 0 0 0 GEORGETOWN MUNI AIRPORT 66 42 74 47 74 / 0 0 0 0 - HONDO MUNI AIRPORT 69 43 74 47 76 / 0 0 0 0 0 SAN MARCOS MUNI AIRPORT 67 44 73 48 75 / 0 0 0 0 - LA GRANGE - FAYETTE REGIONAL 68 46 73 50 75 / 0 0 0 0 - SAN ANTONIO INTL AIRPORT 71 46 75 50 75 / 0 0 0 0 0 STINSON MUNI AIRPORT 70 46 75 50 76 / 0 0 0 0 0 && .EWX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ MESOSCALE/AVIATION...17 SYNOPTIC/GRIDS...ALLEN
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
703 AM EST MON DEC 7 2015 .SYNOPSIS... A WEAK LOW PRESSURE SYSTEM, WILL CROSS THE OHIO VALLEY TODAY. HIGH PRESSURE WILL THEN BUILD IN BEHIND THIS SYSTEM FOR TONIGHT AND TUESDAY. LOW PRESSURE WILL DEVELOP OFF THE CAROLINA COAST TODAY AND DEEPEN AS IT MOVES NORTHEAST INTO THE WESTERN ATLANTIC. && .NEAR TERM /THROUGH TONIGHT/... AS OF 400 AM EST MONDAY... WATCHING TWO AREAS OF PRECIPITATION TODAY. THE FIRST IS WITH AN UPPER LOW THAT WAS TRACKING EAST INTO OHIO AT 4AM AND THE SECOND WITH A DEVELOPING SURFACE LOW OFF THE CAROLINA COAST. WIDELY SCATTERED RAIN HAD DEVELOPED ALONG ANS WEST OF A BLUEFIELD TO BRISTOL LINE. TEMPERATURES WERE SLOWLY WARMING ON THE WEST SIDE OF THE MOUNTAINS WITH DEW POINTS RISING INTO THE LOWER TO MIDDLE 30S. THERE WERE A FEW MESONET SITES IN MERCER...TAZEWELL AND SMYTH COUNTIES WHICH REPORTED TEMPERATURES BELOW JUST BELOW FREEZING. THESE TEMPERATURES WILL RISE ABOVE FREEZING BY 9AM... IF THERE IS ANY RAIN BEFORE THEN...A LIGHT GLAZE OF ICE ON ELEVATED SURFACES WILL BE POSSIBLE. HRRR SHOWED THIS PRECIPITATION DISSIPATING AS IT MOVED EAST THIS MORNING. A LARGER AREA OF SHOWERS WAS CLOSER TO THE UPPER LOW AND WILL REACH WESTERN SECTIONS OF THE COUNTY WARNING AREA AFTER NOON AND MOVE EAST ACROSS THE FORECAST AREA BY 03Z/10PM. CLOUDS WILL SPREAD INTO THE AREA A COUPLE HOURS AHEAD OF THE ARRIVAL OF THE SHOWERS. THE BUFKIT FORECAST SHOWED SOME GOOD MID LEVEL LAPSE RATES AS THE COLD POOL AT 500 MB ASSOCIATED WITH THE UPPER LOW CROSSES THE REGION. MODELS HAVE THE UPPER TROF AND DEEP MOISTURE EAST OF THE FORECAST AREA BY MIDNIGHT. EXPECTING A LAYER OF SHALLOW LOW CLOUDS IN THE WESTERN UPSLOPE AREAS OF SOUTHEAST WEST VIRGINIA OVERNIGHT. RAIN AND CLOUD COVER WITH THE SOUTHEAST LOW WAS EXPECTED TO STAY SOUTHEAST OF THE FORECAST AREA TODAY. COUNTIES IN THE VIRGINIA AND NORTH CAROLINA PIEDMONT WILL HAVE THE MOST SUNSHINE TODAY AND THEREFORE THE WARMEST MAXIMUM TEMPERATURES. STAYED CLOSE TO LOCAL WRF AND THE LATEST RUNS OF GRIDDED LAMP GUIDANCE FOR MAXIMUM TEMPERATURES THIS AFTERNOON. MODELS HAD MORE OF A SPREAD WITH LOWS OVERNIGHT IN THE MOUNTAINS. TRENDED TOWARD COOLER MAV NUMBERS FOR MINIMUM TEMPERATURES. && .SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/... AS OF 300 AM EST MONDAY... WEAK HIGH PRESSURE WILL BE THE CONTROLLING FEATURE OF OUR WEATHER PATTERN ON TUESDAY...WITH THE AXIS OF THE HIGH DRIFTING OFF THE COAST LATE TUESDAY NIGHT AS OUR NEXT COLD FRONT APPROACHES FROM THE MIDWEST REGION. WINDS WILL SHIFT SOUTHERLY AS THE HIGH DRIFTS EAST WHICH...COMBINED WITH ABUNDANT SUNSHINE...WILL HELP PUSH AFTERNOON TEMPERATURES INTO THE UPPER 40S/LOW 50S ACROSS THE MOUNTAINS...AND INTO THE MID/UPPER 50S ACROSS THE PIEDMONT. LOW TEMPERATURES FOR TUESDAY NIGHT WILL BE DEPENDENT ON ELEVATION...WITH THE RIDGES HOLDING WARMER IN THE SOUTHWESTERLY WINDFLOW OFF THE SURFACE...WHILE THE LOWER ELEVATIONS WILL DECOUPLE AND EXPERIENCE RADIATIONAL COOLING. BELIEVE SOME OF THE HIGHER RIDGES WILL REMAIN IN THE LOW/MID 40S OVERNIGHT...WHILE TEMPERATURES WILL FALL INTO THE UPPER 20S TO MID 30S IN LOWER ELEVATIONS. CLOUDS WILL INCREASE DURING EARLY WEDNESDAY MORNING AS THE COLD FRONT APPROACHES...WITH A FEW SHOWERS ENTERING THE AREA JUST BEFORE SUNSET. SOUTHWESTERLY FLOW AHEAD OF THE FRONT WILL MAINTAIN MILD TEMPERATURES...WITH HIGHS REACHING INTO THE 50S AREAWIDE. SHOWER ACTIVITY WILL INCREASE ACROSS THE WESTERN RIDGES AFTER SUNSET...BUT DO NOT EXPECT THIS ACTIVITY TO MAKE MUCH PROGRESS FURTHER EAST AS WINDS SHIFT WEST NORTHWESTERLY WITH FRONTAL PASSAGE. DOWNSLOPE WINDFLOW WILL CAUSE THE SHOWERS TO BREAK UP BY THE TIME THEY REACH THE BLUE RIDGE. ONLY MODEST RAINFALL AMOUNTS ARE EXPECTED...PERHAPS AROUND A TENTH OF AN INCH IN PORTIONS OF SOUTHEAST WEST VIRGINIA. MAY SEE A FEW UPSLOPE SHOWERS LINGER ALONG THE WESTERN RIDGES WEDNESDAY NIGHT...BUT BELIEVE THIS ACTIVITY WILL BE GONE BY SUNRISE THURSDAY...WITH DRY CONDITIONS EXPECTED FOR THE REMAINDER OF THE DAY. IT WONT TAKE LONG FOR WINDS TO SHIFT SOUTHWESTERLY AGAIN AS YET ANOTHER UPPER LEVEL DISTURBANCE SETS UP OVER THE GREAT LAKES. AS SUCH...MILD TEMPERATURES WILL CONTINUE. && .LONG TERM /FRIDAY THROUGH SUNDAY/... AS OF 240 AM EST MONDAY... THE SYNOPTIC WEATHER PATTERN THROUGH SATURDAY ACROSS THE CENTRAL AND EASTERN PARTS OF THE COUNTRY TRANSITIONS INTO A NEARLY ZONAL PATTERN WITH THE POTENTIAL FOR ONE WEAK DISTURBANCE CROSSING THE AREA ON FRIDAY. THIS WILL ALLOW FOR A GENERAL TREND TOWARDS TEMPERATURES EVEN HIGHER THAN NORMAL...BUT AS MUCH AS PERHAPS 15 DEGREES. ISOLATED SHOWERS WILL BE POSSIBLE ACROSS PORTIONS OF MAINLY SOUTHEAST WEST VIRGINIA ON FRIDAY. OTHERWISE THROUGH SATURDAY... EXPECT PRECIPITATION FREE CONDITIONS ACROSS THE AREA. THE FORECAST SPECIFICS AT THE END OF THE FORECAST CYCLE GET A BIT MORE UNCERTAIN. WHILE GUIDANCE BETWEEN THE GFS AND ECMWF AGREE THERE WILL BE A STRONG COLD FRONT PASSAGE EARLY NEXT WEEK...THEY DIFFER REGARDING THE TIMING. THE ECMWF IS A LITTLE QUICKER IN BRINGING THE FRONT THROUGH THE REGION DURING THE DAY MONDAY...WITH THE SLOWER GFS ABOUT 6 TO 12 HOURS LATER. HOWEVER...BOTH MODELS ARE WITHIN SIX HOURS IN REGARDS TO THE ONSET OF SOME PRE-FRONTAL RAIN SHOWERS STARTING LATE SATURDAY NIGHT...WITH A CONTINUATION OF SHOWERS AHEAD OF THE FRONT ON SUNDAY. OUR FORECAST WILL REFLECT THIS SCENARIO SATURDAY NIGHT INTO SUNDAY. TEMPERATURES WILL REMAIN ON THE VERY MILD SIDE...BUT PERHAPS A LITTLE COOLER GIVEN INCREASING CLOUD COVER AND CHANCES OF RAIN SHOWERS. && .AVIATION /12Z MONDAY THROUGH FRIDAY/... AS OF 655 AM EST MONDAY... RADAR SHOWED SCATTERED LIGHT RAIN FROM THE NEW RIVER VALLEY INTO SOUTHEAST WEST VIRGINIA THIS MORNING. CEILINGS JUST ALONG THE WESTERN SLOPES WERE MVFR. VFR CLOUDS EXTENDED BACK INTO THE OHIO VALLEY WHERE AN UPPER LOW WAS MOVING EAST. MORE PRECIPITATION WAS UNDERNEATH THE UPPER LOW IN NORTHERN KENTUCKY AND SOUTHERN OHIO. MODELS WERE IN GOOD AGREEMENT BRINGING THIS PRECIPITATION INTO THE MOUNTAINS AFTER 16Z/NOON AND MOVING IT EAST THROUGHOUT THE DAY. HIGH CONFIDENCE THAT SHOWERS WILL EXIT THE AREA AND BE EAST OF KLYH AND KDAN BY MIDNIGHT TONIGHT. MODERATE CONFIDENCE AS TO HOW LOW CEILINGS WILL BE IN THE WESTERN UPSLOPE AREAS TONIGHT. CLOUDS WILL CLEAR OUT IN THE EAST ONCE THE UPPER LOW MOVES THROUGH BUT KLWB AND KBLF WILL HAVE MVFR CEILINGS THIS EVENING. BUFKIT SOUNDINGS SUGGESTED IFR CEILINGS WERE POSSIBLE AT KBLF OVERNIGHT. EXPECT ANY CEILINGS THIS LOW WILL REMAIN WEST OF KLWB. .EXTENDED AVIATION DISCUSSION... WEAK HIGH PRESSURE FOLLOWS THIS SYSTEM WITH A RETURN TO VFR ON TUESDAY. ANOTHER WEAK UPPER LEVEL DISTURBANCE MAY BRING SOME MVFR CIGS AND ISOLATED SHOWERS TO THE WESTERN SLOPES LATER WEDNESDAY...OTHERWISE CONTINUED VFR INTO FRIDAY. && .EQUIPMENT... AS OF 300 AM EST SUNDAY... T1 LINE IS DOWN PREVENTING DISSEMINATION OF THE BLUEFIELD ASOS OBSERVATION. THE FAA HAS OPENED A TROUBLE TICKET AND IS WORKING ON THE ISSUE. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...AMS NEAR TERM...AMS SHORT TERM...NF LONG TERM...DS AVIATION...AMS/PM EQUIPMENT...JH
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
435 AM EST MON DEC 7 2015 .SYNOPSIS... A WEAK LOW PRESSURE SYSTEM, WILL CROSS THE OHIO VALLEY TODAY. HIGH PRESSURE WILL THEN BUILD IN BEHIND THIS SYSTEM FOR TONIGHT AND TUESDAY. LOW PRESSURE WILL DEVELOP OFF THE CAROLINA COAST TODAY AND DEEPEN AS IT MOVES NORTHEAST INTO THE WESTERN ATLANTIC. && .NEAR TERM /THROUGH TONIGHT/... AS OF 400 AM EST MONDAY... WATCHING TWO AREAS OF PRECIPITATION TODAY. THE FIRST IS WITH AN UPPER LOW THAT WAS TRACKING EAST INTO OHIO AT 4AM AND THE SECOND WITH A DEVELOPING SURFACE LOW OFF THE CAROLINA COAST. WIDELY SCATTERED RAIN HAD DEVELOPED ALONG ANS WEST OF A BLUEFIELD TO BRISTOL LINE. TEMPERATURES WERE SLOWLY WARMING ON THE WEST SIDE OF THE MOUNTAINS WITH DEW POINTS RISING INTO THE LOWER TO MIDDLE 30S. THERE WERE A FEW MESONET SITES IN MERCER...TAZEWELL AND SMYTH COUNTIES WHICH REPORTED TEMPERATURES BELOW JUST BELOW FREEZING. THESE TEMPERATURES WILL RISE ABOVE FREEZING BY 9AM... IF THERE IS ANY RAIN BEFORE THEN...A LIGHT GLAZE OF ICE ON ELEVATED SURFACES WILL BE POSSIBLE. HRRR SHOWED THIS PRECIPITATION DISSIPATING AS IT MOVED EAST THIS MORNING. A LARGER AREA OF SHOWERS WAS CLOSER TO THE UPPER LOW AND WILL REACH WESTERN SECTIONS OF THE COUNTY WARNING AREA AFTER NOON AND MOVE EAST ACROSS THE FORECAST AREA BY 03Z/10PM. CLOUDS WILL SPREAD INTO THE AREA A COUPLE HOURS AHEAD OF THE ARRIVAL OF THE SHOWERS. THE BUFKIT FORECAST SHOWED SOME GOOD MID LEVEL LAPSE RATES AS THE COLD POOL AT 500 MB ASSOCIATED WITH THE UPPER LOW CROSSES THE REGION. MODELS HAVE THE UPPER TROF AND DEEP MOISTURE EAST OF THE FORECAST AREA BY MIDNIGHT. EXPECTING A LAYER OF SHALLOW LOW CLOUDS IN THE WESTERN UPSLOPE AREAS OF SOUTHEAST WEST VIRGINIA OVERNIGHT. RAIN AND CLOUD COVER WITH THE SOUTHEAST LOW WAS EXPECTED TO STAY SOUTHEAST OF THE FORECAST AREA TODAY. COUNTIES IN THE VIRGINIA AND NORTH CAROLINA PIEDMONT WILL HAVE THE MOST SUNSHINE TODAY AND THEREFORE THE WARMEST MAXIMUM TEMPERATURES. STAYED CLOSE TO LOCAL WRF AND THE LATEST RUNS OF GRIDDED LAMP GUIDANCE FOR MAXIMUM TEMPERATURES THIS AFTERNOON. MODELS HAD MORE OF A SPREAD WITH LOWS OVERNIGHT IN THE MOUNTAINS. TRENDED TOWARD COOLER MAV NUMBERS FOR MINIMUM TEMPERATURES. && .SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/... AS OF 300 AM EST MONDAY... WEAK HIGH PRESSURE WILL BE THE CONTROLLING FEATURE OF OUR WEATHER PATTERN ON TUESDAY...WITH THE AXIS OF THE HIGH DRIFTING OFF THE COAST LATE TUESDAY NIGHT AS OUR NEXT COLD FRONT APPROACHES FROM THE MIDWEST REGION. WINDS WILL SHIFT SOUTHERLY AS THE HIGH DRIFTS EAST WHICH...COMBINED WITH ABUNDANT SUNSHINE...WILL HELP PUSH AFTERNOON TEMPERATURES INTO THE UPPER 40S/LOW 50S ACROSS THE MOUNTAINS...AND INTO THE MID/UPPER 50S ACROSS THE PIEDMONT. LOW TEMPERATURES FOR TUESDAY NIGHT WILL BE DEPENDENT ON ELEVATION...WITH THE RIDGES HOLDING WARMER IN THE SOUTHWESTERLY WINDFLOW OFF THE SURFACE...WHILE THE LOWER ELEVATIONS WILL DECOUPLE AND EXPERIENCE RADIATIONAL COOLING. BELIEVE SOME OF THE HIGHER RIDGES WILL REMAIN IN THE LOW/MID 40S OVERNIGHT...WHILE TEMPERATURES WILL FALL INTO THE UPPER 20S TO MID 30S IN LOWER ELEVATIONS. CLOUDS WILL INCREASE DURING EARLY WEDNESDAY MORNING AS THE COLD FRONT APPROACHES...WITH A FEW SHOWERS ENTERING THE AREA JUST BEFORE SUNSET. SOUTHWESTERLY FLOW AHEAD OF THE FRONT WILL MAINTAIN MILD TEMPERATURES...WITH HIGHS REACHING INTO THE 50S AREAWIDE. SHOWER ACTIVITY WILL INCREASE ACROSS THE WESTERN RIDGES AFTER SUNSET...BUT DO NOT EXPECT THIS ACTIVITY TO MAKE MUCH PROGRESS FURTHER EAST AS WINDS SHIFT WEST NORTHWESTERLY WITH FRONTAL PASSAGE. DOWNSLOPE WINDFLOW WILL CAUSE THE SHOWERS TO BREAK UP BY THE TIME THEY REACH THE BLUE RIDGE. ONLY MODEST RAINFALL AMOUNTS ARE EXPECTED...PERHAPS AROUND A TENTH OF AN INCH IN PORTIONS OF SOUTHEAST WEST VIRGINIA. MAY SEE A FEW UPSLOPE SHOWERS LINGER ALONG THE WESTERN RIDGES WEDNESDAY NIGHT...BUT BELIEVE THIS ACTIVITY WILL BE GONE BY SUNRISE THURSDAY...WITH DRY CONDITIONS EXPECTED FOR THE REMAINDER OF THE DAY. IT WONT TAKE LONG FOR WINDS TO SHIFT SOUTHWESTERLY AGAIN AS YET ANOTHER UPPER LEVEL DISTURBANCE SETS UP OVER THE GREAT LAKES. AS SUCH...MILD TEMPERATURES WILL CONTINUE. && .LONG TERM /FRIDAY THROUGH SUNDAY/... AS OF 240 AM EST MONDAY... THE SYNOPTIC WEATHER PATTERN THROUGH SATURDAY ACROSS THE CENTRAL AND EASTERN PARTS OF THE COUNTRY TRANSITIONS INTO A NEARLY ZONAL PATTERN WITH THE POTENTIAL FOR ONE WEAK DISTURBANCE CROSSING THE AREA ON FRIDAY. THIS WILL ALLOW FOR A GENERAL TREND TOWARDS TEMPERATURES EVEN HIGHER THAN NORMAL...BUT AS MUCH AS PERHAPS 15 DEGREES. ISOLATED SHOWERS WILL BE POSSIBLE ACROSS PORTIONS OF MAINLY SOUTHEAST WEST VIRGINIA ON FRIDAY. OTHERWISE THROUGH SATURDAY... EXPECT PRECIPITATION FREE CONDITIONS ACROSS THE AREA. THE FORECAST SPECIFICS AT THE END OF THE FORECAST CYCLE GET A BIT MORE UNCERTAIN. WHILE GUIDANCE BETWEEN THE GFS AND ECMWF AGREE THERE WILL BE A STRONG COLD FRONT PASSAGE EARLY NEXT WEEK...THEY DIFFER REGARDING THE TIMING. THE ECMWF IS A LITTLE QUICKER IN BRINGING THE FRONT THROUGH THE REGION DURING THE DAY MONDAY...WITH THE SLOWER GFS ABOUT 6 TO 12 HOURS LATER. HOWEVER...BOTH MODELS ARE WITHIN SIX HOURS IN REGARDS TO THE ONSET OF SOME PRE-FRONTAL RAIN SHOWERS STARTING LATE SATURDAY NIGHT...WITH A CONTINUATION OF SHOWERS AHEAD OF THE FRONT ON SUNDAY. OUR FORECAST WILL REFLECT THIS SCENARIO SATURDAY NIGHT INTO SUNDAY. TEMPERATURES WILL REMAIN ON THE VERY MILD SIDE...BUT PERHAPS A LITTLE COOLER GIVEN INCREASING CLOUD COVER AND CHANCES OF RAIN SHOWERS. && .AVIATION /10Z MONDAY THROUGH FRIDAY/... AS OF 1000 PM EST SUNDAY... HIGH CONFIDENCE IN VFR/LIGHT WIND CONDITIONS OVERNIGHT FOR ALL TAF SITES...FOLLOWED BY INCREASING CHANCES FOR BELOW VFR FOR THE DAYLIGHT HOURS MONDAY. SATELLITE IMAGES CURRENTLY SHOW JUST SOME HIGH CIRRUS OVER THE AREA AND IT SHOULD REMAIN THIS WAY FOR MOST OF THE OVERNIGHT. REGIONAL SOUNDINGS ARE BEGINNING TO SHOW A RETURN OF MOISTURE BETWEEN 700-900 MB...THUS WOULD EXPECT DEVELOPMENT OF A CLOUD LAYER BETWEEN 3-7KFT AGL LATER TONIGHT AND EARLY MONDAY. A VIGOROUS BUT MOISTURE STARVED CLOSED LOW WITH A WEAK SURFACE REFLECTION WILL MOVE INTO THE REGION FROM THE WEST LATE TONIGHT. THIS WILL/SHOULD RESULT IN THE DEVELOPMENT OF A LAYER OF LOW LEVEL CLOUDINESS PRIOR TO DAYBREAK MONDAY WITH INCREASING CHANCE FOR PRECIPITATION AS WE PROGRESS THROUGH THE DAY MONDAY. HAVE MAINTAINED A DRY FORECAST AT ALL TAF SITES PRIOR TO 12Z/7AM MONDAY. AS THE SYSTEM MOVES THROUGH THE REGION IT WILL BECOME QUITE FRAGMENTED AS IT TRANSFERS ENERGY TO A NEW LOW DEVELOPING OFF THE COAST. THIS SHOULD ALLOW SITES FROM THE BLUE RIDGE EASTWARD TO MAINTAIN VFR CONDITIONS IN LIMITED SHOWER ACTIVITY WHILE KLWB/KBCB AND ESPECIALLY KBLF EXPERIENCE MVFR/IFR CONDITIONS WITH SOME WEAK UPSLOPE AS WINDS BECOME MORE NWLY. .EXTENDED AVIATION DISCUSSION... WEAK HIGH PRESSURE FOLLOWS THIS SYSTEM WITH A RETURN TO VFR ON TUESDAY. ANOTHER WEAK UPPER LEVEL DISTURBANCE MAY BRING SOME MVFR CIGS AND ISOLATED SHOWERS TO THE WESTERN SLOPES LATER WEDNESDAY...OTHERWISE CONTINUED VFR INTO THURSDAY. && .EQUIPMENT... AS OF 300 AM EST SUNDAY... T1 LINE IS DOWN PREVENTING DISSEMINATION OF THE BLUEFIELD ASOS OBSERVATION. THE FAA HAS OPENED A TROUBLE TICKET AND IS WORKING ON THE ISSUE. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...AMS NEAR TERM...AMS SHORT TERM...NF LONG TERM...DS AVIATION...MBS/PM EQUIPMENT...JH
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
852 PM CST TUE DEC 8 2015 .UPDATE... ADJUSTED POPS AND WEATHER TO LEAN MORE TOWARD A FEW SPRINKLES AND REDUCE THE CHANCE FOR MEASURABLE RAIN AS RAP FORECAST SOUNDINGS REFLECTING THE DEEP DRY LAYER ABOVE THE NEAR-SURFACE INVERSION SHOWN ON DVN AND GRB 00Z SOUNDINGS LEADING TO EVAPORATION WITH RETURNS ON AREA RADARS MAINLY VIRGA. LEFT SOME LOW CHANCE POPS IN THE FAR EAST AFTER 06Z AS HI- RES/RAPID UPDATE MODELS INDICATE POTENTIAL FOR LIGHT PCPN DEVELOPING IN THE LOW- LEVEL FRONTOGENESIS ALONG SURFACE BOUNDARY. ALSO LEFT PATCHY FOG IN WITH SATURATED NEAR- SURFACE LAYER UNDER SHALLOW POST- FRONTAL INVERSION. && .AVIATION/06Z TAFS/... SOME PATCHY MVFR CIGS HAVE PUSHED INTO SOUTHERN WISCONSIN WITH SURFACE MOISTURE ADVECTION IN SOUTHERLY WINDS AHEAD OF SURFACE TROUGH. WILL MONITOR TRENDS UP TO ISSUANCE BUT EXPECT CIGS TO DROP TO AT LEAST MVFR LEVELS...IF NOT IFR...AROUND/AFTER 09Z THROUGH THE EARLY DAYLIGHT HOURS BEHIND TROUGH AS IT CROSSES AREA OVERNIGHT. LOOKS AS IF FOG WILL REMAIN PATCHY UNDER THE STRATUS DECK OVERNIGHT INTO THE EARLY MORNING. WILL KEEP PCPN OUT OF TAF SITES...THOUGH NOT OUT OF THE QUESTION THAT ANY OF THE SITES COULD SEE A FEW SPRINKLES WITH THE TROUGH PASSAGE. EXPECT VFR CONDITIONS TO RETURN AFTER 15Z WITH DECREASING CLOUD COVER...THOUGH IT WILL BE BRIEF AS MID-HIGH LEVEL CLOUDS INCREASE AS NEXT WAVE IN A SERIES APPROACHES. && .PREV DISCUSSION... /ISSUED 301 PM CST TUE DEC 8 2015/ TONIGHT AND WEDNESDAY...FORECAST CONFIDENCE IS MEDIUM. LARGE SCALE TROUGHING WILL PROGRESS FROM THE MISSISSIPPI VALLEY THIS EVENING INTO THE EASTERN GREAT LAKES...OHIO VALLEY...AND TENNESSEE VALLEY ON WEDNESDAY. AN ACCOMPANYING COLD FRONT WILL SWEEP EASTWARD THROUGH THE PERIOD...CLEARING SOUTHERN WISCONSIN WEDNESDAY MORNING. WEAK LOW PRESSURE ALONG THE SFC BAROCLINIC ZONE WILL LIFT NORTHEAST INTO NORTHERN WISCONSIN...TAKING THE BULK OF THE MOISTURE WITH IT. MESO MODELS PAINT SOME LIGHT QPF ALONG AND WEST OF MADISON THIS EVENING AND THERE COULD BE A SHOWER OR TWO. HOWEVER...WITH VERY DRY SOUNDINGS THIS MAY END UP BEING ONLY SPRINKLES...IF THAT. LOW TEMPERATURES WILL RANGE FROM AROUND 35 IN THE DELLS TO AROUND 40 ALONG THE SOUTHEASTERN LAKESHORE. SFC COLD FRONT PASSES THROUGH WEDNESDAY MORNING WITH ANY SHOWERS OR SPRINKLES DEPARTING THE EAST DURING THE MORNING. TRANSIENT RIDGING THEN TAKES HOLD BY AFTERNOON WITH SLOW CLEARING. DESPITE THE FRONTAL PASSAGE...850 MB TEMPERATURES REMAIN FAIRLY WARM...AND HIGHS IN THE 40S ARE EXPECTED EVEN WITH RESIDUAL CLOUD COVER. WEDNESDAY NIGHT THROUGH FRIDAY...FORECAST CONFIDENCE IS MEDIUM. A RATHER CLOUDY BUT STILL MILD PERIOD AS WE REMAIN UNDER A FAST ZONAL MID LEVEL FLOW. THIS JET STREAM WILL BRING ANOTHER SHORT WAVE THROUGH HERE ON THURSDAY AND MAY SPIT OUT SOME LIGHT RAIN ACROSS THE NORTHERN FORECAST AREA. RIDGING ARRIVES FOR FRIDAY AS A LONG ADVERTISED PATTERN SHIFT BEGINS. FRIDAY LOOKS DRY AT THIS TIME WITH TEMPS A BIT COOLER THAN THURSDAY DUE TO SOME COOL AIR ADVECTION IN THE WAKE OF THE DEPARTING SHORT WAVE. SATURDAY THROUGH MONDAY...FORECAST CONFIDENCE IS LOW. THIS PATTERN SHIFT WILL FEATURE A HIGHER AMPLITUDE TROUGH DIGGING OVER THE WESTERN U.S. WITH A PARTNERED RIDGE TAKING SHAPE OVER THE EAST. WE WILL BE IN THE TRANSITIONAL MILD BUT UNSETTLED SOUTHWEST FLOW BETWEEN THESE TWO SYSTEMS FOR THE WEEKEND. THE MODELS CONTINUE TO STRUGGLE TO COME UP WITH A CONSENSUS ON HOW THE MID LEVEL ENERGY WILL TRANSFER OUT OF THE SOUTHWEST U.S. AND INTO THE MID SECTION OF THE U.S. AND EVENTUALLY THE GREAT LAKES BY SUNDAY NIGHT OR EVEN MONDAY. IN GENERAL...THE GFS IS VERY QUICK...TAKING THE ENERGY QUICKLY NORTHEAST INTO OUR AREA...WITH THE UPPER LOW CLOSING OFF OVR MN/WI BY END OF THE DAY SUNDAY. AT THAT SAME TIME...THE ECMWF HAS A NEARLY CUT-OFF CLOSED LOW OVER OKLAHOMA/TX...EVENTUALLY DRIFTING THROUGH THE OHIO RIVER VALLEY ON MONDAY. THE CANADIAN LOOKS LIKE A COMPROMISE WITH A HIGH AMPLITUDE TROF FROM WISCONSIN SOUTH THROUGH THE LOWER MS RIVER VALLEY...IN THE PROCESS OF GOING NEG TILT AND CLOSING OFF OVER THE NW GREAT LAKES. GIVEN ALL THE SOLUTIONS...IT STILL LOOKS LIKE SOUTHERN WISCONSIN WILL STAY TOO WARM FOR ANY SNOW...BUT THEY ALL SPELL THE LIKELIHOOD OF A ROUND...POSSIBLY TWO...OF DECENT RAINFALL. WE/LL HAVE TO KEEP AN EYE ON THIS AS SOILS ARE SATURATED AND RIVERS ARE STILL A BIT SWOLLEN FROM OUR LAST RAIN EVENT. FOR NOW...ANY SNOW WITH THIS STORM SHOULD BE LIMITED TO NORTHERN WISCONSIN. BUT...STAY TUNED IT IS DECEMBER AFTER ALL. AVIATION/00Z TAFS/...CIGS WILL LOWER AFTER 00Z THIS EVENING WITH LOW PRESSURE APPROACHING. LATEST MODEL GUIDANCE HAS BACKED OFF A LITTLE ON WIDESPREAD IFR CIGS LATE TONIGHT/EARLY TOMORROW. STILL DON/T THINK THEY ARE TOTALLY OUT OF THE QUESTION THOUGH. SPRINKLES...AND PERHAPS A LIGHT SHOWER...ARE POSSIBLE OVERNIGHT MAINLY NORTH OF MKE/UES/MSN. FOR NOW KEPT VCSH OUT OF THE TAFS DUE TO LOW CONFIDENCE IN OCCURRENCE. SOUTHERLY WINDS WILL VEER WESTERLY FOLLOWING A COLD FRONTAL PASSAGE WEDS AM. TIMING OF WIND SHIFT SHOULD BE AROUND 9-12Z. MARINE... A TIGHT PRESSURE GRADIENT IS EXPECTED ON THURSDAY AND THURSDAY NIGHT IN ASSOCIATION WITH PASSING LOW PRESSURE. WINDS AND WAVES MAY REACH SMALL CRAFT ADVISORY LEVELS DURING THIS TIME. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...NONE. LM...NONE. && $$ UPDATE...REM TONIGHT/WEDNESDAY AND AVIATION/MARINE...SPM WEDNESDAY NIGHT THROUGH TUESDAY...DAVIS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
303 PM CST MON DEC 7 2015 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 303 PM CST MON DEC 7 2015 CHALLENGES TONIGHT INCLUDE CLOUD TRENDS AND TEMPERATURES. WILL FOLLOW A BLEND OF THE LATEST RAP 0.5 KM RELATIVE HUMIDITY OUTPUT AND THE CIRA SYNTHETIC FOG PRODUCT...BOTH OF WHICH CLOSELY MATCH CURRENT REALITY. CLEARING LINE AS OF 07.20Z EXTENDS FROM NEAR EAU CLAIRE TO DECORAH... MOVING TO THE EAST AROUND 25 MPH. BEFORE SUNSET...EXPECT AN HOUR OR TWO OF INCREASING SUNSHINE AS CLOUDS CONTINUE TO DISSIPATE FROM WEST TO EAST. HOWEVER...LOW CLOUDS EXPECTED TO REDEVELOP ACROSS SOUTH-CENTRAL MN IN COOLER AIR MASS BEHIND THE DEPARTING SHORT-WAVE ALOFT AND THEN MOVE OVER THE FORECAST AREA THIS EVENING. SHOULD STILL SEE A RATHER PROGRESSIVE WEST TO EAST MOVEMENT OF CLOUD COVER GIVEN LOW-LEVEL WINDS TURNING TO THE WEST AROUND 20 KTS...BUT AREAS EAST OF THE MS RIVER LIKELY TO REMAIN MOSTLY CLOUDY FOR A GOOD PORTION OF THE NIGHT. AS A RESULT... INCREASED LOW TEMPERATURES IN THESE AREAS INTO THE MID 30S. FARTHER WEST WHERE SOME CLEARING IS POSSIBLE...TEMPERATURES WILL FALL INTO THE LOWER 30S...POSSIBLY INTO THE UPPER 20S FOR FAVORED COLD SPOTS. ALSO ADDED SOME PATCHY FOG AFTER MIDNIGHT...BUT COVERAGE/RELATIVE IMPACT WILL BE MUCH LESS THAN LAST NIGHT. WHILE THERE MAY BE SOME PEAKS OF SUN EARLY TUESDAY...CLOUD COVER WILL QUICKLY INCREASE FROM WEST TO EAST AHEAD OF THE NEXT SHORT- WAVE ALOFT. INITIAL DRY AIR MASS BELOW 700 HPA WILL LIMIT PRECIP TUESDAY AFTERNOON...BUT MAY SEE SOME RAIN REACH THE GROUND TUESDAY EVENING AS LOWER LEVELS SATURATE AND 850 TO 700 HPA TROUGH MOVES ACROSS NORTHERN WI. BEST CHANCES FOR MEASURABLE RAIN WILL BE ALONG AND NORTH OF I-94...BUT EVEN THERE ONLY A FEW HUNDREDTHS ARE FORECAST. LOOK FOR HIGHS TUESDAY IN THE MID TO UPPER 40S WITH LIGHT SOUTHERLY WIND. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 303 PM CST MON DEC 7 2015 WEDNESDAY THROUGH SATURDAY...ABOVE NORMAL TEMPERATURES WILL CONTINUE...GENERALLY 15 TO 20 DEGREES HIGHER THAN WHAT IS TYPICAL THIS TIME OF YEAR. THESE TEMPERATURES WILL MAX OUT ON THURSDAY GIVEN A VERY WARM START TO THE DAY (LOWS IN THE UPPER 30S TO NEAR 40 DEGREES) AND 925 HPA TEMPERATURES FROM +4 TO +7 CELSIUS. AS A RESULT...EXPECT WIDESPREAD LOWER 50S FOR THURSDAY/S HIGHS. TEMPERATURES WILL REMAIN ABOVE NORMAL SUNDAY INTO EARLY NEXT WEEK...BUT WILL FALL TO SOMETHING MORE COMMON FOR MID-DECEMBER WITH HIGHS BACK INTO THE 30S AFTER PASSAGE OF A STRONG COLD FRONT ON SATURDAY. PRECIP-WISE...ANOTHER PACIFIC SHORT-WAVE MOVES ACROSS THE UPPER MIDWEST ON THURSDAY. THERE IS MODEST SPREAD AMONG THE SREF MEMBERS CONCERNING THE STRENGTH AND TIMING OF THIS TROUGH...BUT IT APPEARS THE BEST SATURATION/LIFT WILL PASS NORTH OF THE FORECAST AREA. WILL CONTINUE THE IDEA OF CHANCE POPS NORTH OF I-94 WITH LITTLE TO NO ACCUMULATION FARTHER SOUTH. THERMAL PROFILE IS WARM ENOUGH FOR ANYTHING THAT DOES ACCUMULATE TO FALL AS RAIN. STILL WATCHING THE DEVELOPMENT OF A MUCH LARGER TROUGH ACROSS THE WESTERN CONUS FOR THE WEEKEND. HOWEVER...THE 07.12Z ECMWF IS SLOWER AND MUCH DEEPER WITH THIS FEATURE COMPARED TO ITS GFS COUNTERPART. WILL KEEP BROAD BRUSH 20 TO 30 POPS FOR THE WEEKEND INTO EARLY NEXT WEEK FOR NOW WITH THE GFS PRODUCING MOST OF ITS PRECIP TO THE SOUTH AND EAST OF THE FORECAST AREA ALONG THE PRIMARY BAROCLINIC ZONE...WHEREAS THE ECMWF/S SLOWER SOLUTION BRINGS AN AREA OF PRECIP FARTHER WEST ACROSS PORTIONS OF THE FORECAST AREA. AS NOTED ABOVE...TEMPERATURES WILL BE COOLER THIS WEEKEND...SO THE POTENTIAL EXISTS FOR SOME MIXED PRECIP OR EVEN SNOW. HOWEVER...CONFIDENCE IS LOW ON THE STORM TRACK AND THEREFORE ITS THERMAL PROFILE. WILL BE ABLE TO FINE-TUNE FORECAST AS MODELS WORK THROUGH SOME OF THESE DIFFERENCES OVER THE NEXT SEVERAL CYCLES. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1140 AM CST MON DEC 7 2015 IFR/MVFR CLOUDS REMAIN BELOW AN INVERSION. SOUNDINGS SUGGEST THAT THE MVFR DECK AT KLSE WILL REMAIN THROUGH THE TAF PERIOD. MEANWHILE KRST WILL GRADUALLY LOSE ITS IFR DECK LATE THIS EVENING. WITH IT LOSING THIS LOW DECK...SEVERAL OF THE MOS GUIDANCE SHOW THAT DENSE FOG WILL ONCE AGAIN DEVELOP BETWEEN 08.10Z AND 08.14Z. HOWEVER THIS GUIDANCE IS ALSO OVERDOING THE FOG RIGHT NOW...SO CONFIDENCE IS NOT THAT HIGH. DUE TO THIS...JUST WENT WITH A TEMPO 1 STATUE MILE WITH BKN005 DECK DURING THIS TIME FRAME. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...ROGERS LONG TERM...ROGERS AVIATION...BOYNE
AREA FORECAST DISCUSSION
NWS CARIBOU ME
1242 AM EST WED DEC 9 2015 .SYNOPSIS... HIGH PRESSURE WILL REMAIN OVER THE AREA TONIGHT THROUGH WEDNESDAY. THE HIGH WILL MOVE EAST WEDNESDAY NIGHT AS A WEAK TROUGH OF LOW PRESSURE APPROACHES FROM THE WEST. THIS TROUGH IS EXPECTED TO CROSS THE REGION ON THURSDAY. && .NEAR TERM /THROUGH TONIGHT/... 11:30 PM UPDATE...MODIFIED SOME TEMPERATURES ACROSS THE NORTH WHERE SOME VALLEYS HAVE BEGUN TO COOL QUICKLY. ALSO MODIFIED CLOUD COVER JUST A BIT WITH SOME MID AND HIGH CLOUDS BEGINNING TO MOVE INTO WESTERN AREAS. RADAR SHOWS SOME WEAK ECHOES IN THE FAR NORTHWEST SO INCLUDED A SLIGHT CHANCE OF SNOW SHOWERS IN THE NORTHWEST. OTHERWISE, NO MAJOR CHANGES THIS HOUR. PREVIOUS DISCUSSION... MAIN CHALLENGE THIS TERM AS HAS BEEN THE PAST FEW DAYS WILL BE THE CLOUDS AND TEMPS. SURFACE ANALYSIS SHOWED LOW PRES PASSING WELL SE OF THE AREA W/THE MID AND HIGH CLOUDS ASSOCIATED W/IT STARING TO PULL OUT OF THE DOWNEAST AND COASTAL AREA. FURTHER N AND W, SATELLITE IMAGERY SHOWED SOME CLOUDS AROUND AS WEAK UPPER IMPULSE PASSES BY TO THE N DESPITE HIGH PRES AT THE SURFACE. DOWNEAST AND THE COAST SHOULD REMAIN MOSTLY CLEAR OVERNIGHT W/HIGH PRES PULLING E. THOSE CLOUDS ACROSS THE NORTHERN SECTIONS WILL SLOWLY ERODE THIS EVENING, BUT MORE CLOUDS ARE FORECAST TO SET UP LATER TONIGHT AS A LIGHT ESE FLOW SETS UP ALLOWING FOR MOISTURE TO GET TRAPPED UNDER THE INVERSION. THE HRRR DOING WELL W/CURRENT SETUP AND SHOWED THE LLVL MOISTURE SETTING UP OVER EASTERN AND NORTHERN SECTIONS AFTER MIDNIGHT. TEMPS WILL VARY OVERNIGHT DEPENDENT ON THE CLOUDS. THIS WILL MAKE IT FOR A TOUGHT FORECAST. DECIDED TO GO W/UPPER TEENS TO LOWER 20S ACROSS THE NORTHERN 1/2 OF THE CWA W/THE COLDEST TEMPS IN THE LOW LYING AREAS AND NEAR RIVER VALLEYS. STAYED W/MID-UPPER 20S DOWNEAST AND THE COAST. THIS WILL NEED TO BE MONITORED AS SOME OF THE LOW LYING AREAS IN THIS REGION COULD GO COLDER DEPENDING ON LONGEVITY OF THE CLEARING. PATCHY FOG POSSIBLE ESPECIALLY ALONG THE RIVER VALLEYS. LOW CLOUDS WILL TAKE SOME TIME TO ERODE WEDNESDAY MORNING W/THE WEAK SE FLOW IN PLACE. DIRUNAL EFFECTS SHOULD AID IN ALLOWING FOR THE CLOUD DECK TO LIFT AND DISSIPATE SOME W/SUNSHINE. DAYTIME TEMPERATURES WILL BE A BIT ABOVE NORMAL FOR EARLY DECEMBER. && .SHORT TERM /THURSDAY THROUGH FRIDAY/... HIGH PRESSURE WILL MOVE OFF THE COAST WEDNESDAY NIGHT WHILE AT THE SAME TIME LOW PRESSURE WILL PASS TO THE NORTHWEST OF NEW ENGLAND. THIS WILL RESULT IN A PERIOD OF SNOW AND RAIN AS WARM ADVECTION/OVERUNNING TAKE PLACE. SNOW AMOUNTS ARE EXPECTED TO BE MINIMAL AND CONFINED TO THE NORTH AND WEST AS THE PRECIPITATION IS EXPECTED TO QUICKLY CHANGE TO RAIN. ANOTHER PERIOD OF RAIN WITH SOME SNOW MIXED IS EXPECTED FRIDAY AS LOW PRESSURE DEVELOPS ACROSS NEW ENGLAND. && .LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/... LOW PRESSURE MOVING ACROSS QUEBEC WILL PUSH A WEAK FRONT ACROSS THE STATE FRI EVENING. A FEW SHWRS ARE EXPECTED IN ASSOCIATION, THOUGH BY THE 00Z SAT MUCH OF THE PRECIP MAY BE OVER FAR ERN & NRN MAINE, DEPARTING INTO NEW BRUNSWICK AS THE NIGHT PROGRESSES. AN UPR RIDGE AND WEAK SFC HIGH THEN BUILDS ACROSS THE AREA, ALLOWING FOR CLEARING SAT INTO AT LEAST SUN AM. BEYOND THEN, MODEL AGREEMENT BREAKS DOWN. WHILE BOTH THE GFS AND ECMWF WOULD AGREE ON SOME MORE ACTIVE WEATHER MONDAY INTO TUESDAY, THEY HAVE COMPLETELY DIFFERENT SOLUTIONS. THE GFS SHOWS ONE VERY POTENT SFC LOW DRIVEN BY A DEEP UPR TROF MOVING INTO ERN CANADA AND PUSHING A STRONG FRONT ACROSS THE STATE ON MON. THIS SOLUTION WOULD BRING ABUNDANT RAINFALL LATE SUN NIGHT THRU MON AFTERNOON, SWITCHING TO SNOW BEHIND THE FRONT AND LINGERING INTO TUE AFTERNOON. THE ECMWF IS COMPLETELY DIFFERENT, SHOWING ONE LOW DRIVEN BY A JET STREAK CROSSING THE CWA MON, AND A SECOND LOW DRIVEN BY AN UPR TROF OR CUT-OFF MOVING ACROSS ON TUE. HOWEVER, THE ECMWF HAS BEEN RATHER VARIABLE RUN-TO- RUN, WHILE THE GFS HAS BEEN A BIT MORE CONSISTENT. GIVEN THIS, AND THE FACT THAT THE CANADIAN APPEARS CLOSER TO THE GFS, ANY EDITS MADE SUN THRU TUE WERE SKEWED TOWARD THE GFS SOLUTION. && .AVIATION /06Z WEDNESDAY THROUGH SUNDAY/... NEAR TERM: VFR LATE THIS EVENING. A LLVL DECK, MVFR AND POSSIBLY EVEN IFR COULD DEVELOP AFTER MIDNIGHT AND LINGER INTO WED MORNING AS LIGHT ESE FLOW DEVELOPS. THIS DECK LOOKS LIKE IT WILL SET UP E OF THE BGR AND BHB TERMINALS. SHORT TERM: MVFR/VFR CONDITIONS ARE EXPECTED THURSDAY AND FRIDAY. && .MARINE... NEAR TERM: THE WIND AND SEAS ARE EXPECTED TO REMAIN BELOW SMALL CRAFT ADVISORY LEVELS THROUGH WEDNESDAY. SHORT TERM: HAVE USED A BLEND OF THE NAM12 AND GFS40 FOR WINDS. A SOUTHERLY FETCH WILL DEVELOP FROM THE GULF OF MAINE SOUTHWARD THURSDAY WITH WAVE HEIGHTS BUILDING TO AROUND 6 FEET/7 SECONDS. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...NONE. MARINE...NONE. && $$ NEAR TERM...BLOOMER SHORT TERM...NORCROSS LONG TERM...NORCROSS AVIATION...BLOOMER/NORCROSS MARINE...BLOOMER/NORCROSS
AREA FORECAST DISCUSSION
NWS CARIBOU ME
1123 PM EST TUE DEC 8 2015 .SYNOPSIS... HIGH PRESSURE WILL REMAIN OVER THE AREA TONIGHT THROUGH WEDNESDAY. THE HIGH WILL MOVE EAST WEDNESDAY NIGHT AS A WEAK TROUGH OF LOW PRESSURE APPROACHES FRO THE WEEST. THIS TROUGH IS EXPECTED TO CROSS THE REGION ON THURSDAY. && .NEAR TERM /THROUGH WEDNESDAY/... 11:30 PM UPDATE...MODIFIED SOME TEMPERATURES ACROSS THE NORTH WHERE SOME VALLEYS HAVE BEGUN TO COOL QUICKLY. ALSO MODIFIED CLOUD COVER JUST A BIT WITH SOME MID AND HIGH CLOUDS BEGINNING TO MOVE INTO WESTERN AREAS. RADAR SHOWS SOME WEAK ECHOES IN THE FAR NORTHWEST SO INCLUDED A SLIGHT CHANCE OF SNOW SHOWERS IN THE NORTHWEST. OTHERWISE, NO MAJOR CHANGES THIS HOUR. PREVIOUS DISCUSSION... MAIN CHALLENGE THIS TERM AS HAS BEEN THE PAST FEW DAYS WILL BE THE CLOUDS AND TEMPS. SURFACE ANALYSIS SHOWED LOW PRES PASSING WELL SE OF THE AREA W/THE MID AND HIGH CLOUDS ASSOCIATED W/IT STARING TO PULL OUT OF THE DOWNEAST AND COASTAL AREA. FURTHER N AND W, SATELLITE IMAGERY SHOWED SOME CLOUDS AROUND AS WEAK UPPER IMPULSE PASSES BY TO THE N DESPITE HIGH PRES AT THE SURFACE. DOWNEAST AND THE COAST SHOULD REMAIN MOSTLY CLEAR OVERNIGHT W/HIGH PRES PULLING E. THOSE CLOUDS ACROSS THE NORTHERN SECTIONS WILL SLOWLY ERODE THIS EVENING, BUT MORE CLOUDS ARE FORECAST TO SET UP LATER TONIGHT AS A LIGHT ESE FLOW SETS UP ALLOWING FOR MOISTURE TO GET TRAPPED UNDER THE INVERSION. THE HRRR DOING WELL W/CURRENT SETUP AND SHOWED THE LLVL MOISTURE SETTING UP OVER EASTERN AND NORTHERN SECTIONS AFTER MIDNIGHT. TEMPS WILL VARY OVERNIGHT DEPENDENT ON THE CLOUDS. THIS WILL MAKE IT FOR A TOUGHT FORECAST. DECIDED TO GO W/UPPER TEENS TO LOWER 20S ACROSS THE NORTHERN 1/2 OF THE CWA W/THE COLDEST TEMPS IN THE LOW LYING AREAS AND NEAR RIVER VALLEYS. STAYED W/MID-UPPER 20S DOWNEAST AND THE COAST. THIS WILL NEED TO BE MONITORED AS SOME OF THE LOW LYING AREAS IN THIS REGION COULD GO COLDER DEPENDING ON LONGEVITY OF THE CLEARING. PATCHY FOG POSSIBLE ESPECIALLY ALONG THE RIVER VALLEYS. LOW CLOUDS WILL TAKE SOME TIME TO ERODE WEDNESDAY MORNING W/THE WEAK SE FLOW IN PLACE. DIRUNAL EFFECTS SHOULD AID IN ALLOWING FOR THE CLOUD DECK TO LIFT AND DISSIPATE SOME W/SUNSHINE. DAYTIME TEMPERATURES WILL BE A BIT ABOVE NORMAL FOR EARLY DECEMBER. && .SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/... HIGH PRESSURE WILL MOVE OFF THE COAST WEDNESDAY NIGHT WHILE AT THE SAME TIME LOW PRESSURE WILL PASS TO THE NORTHWEST OF NEW ENGLAND. THIS WILL RESULT IN A PERIOD OF SNOW AND RAIN AS WARM ADVECTION/OVERUNNING TAKE PLACE. SNOW AMOUNTS ARE EXPECTED TO BE MINIMAL AND CONFINED TO THE NORTH AND WEST AS THE PRECIPITATION IS EXPECTED TO QUICKLY CHANGE TO RAIN. ANOTHER PERIOD OF RAIN WITH SOME SNOW MIXED IS EXPECTED FRIDAY AS LOW PRESSURE DEVELOPS ACROSS NEW ENGLAND. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... LOW PRESSURE MOVING ACROSS QUEBEC WILL PUSH A WEAK FRONT ACROSS THE STATE FRI EVENING. A FEW SHWRS ARE EXPECTED IN ASSOCIATION, THOUGH BY THE 00Z SAT MUCH OF THE PRECIP MAY BE OVER FAR ERN & NRN MAINE, DEPARTING INTO NEW BRUNSWICK AS THE NIGHT PROGRESSES. AN UPR RIDGE AND WEAK SFC HIGH THEN BUILDS ACROSS THE AREA, ALLOWING FOR CLEARING SAT INTO AT LEAST SUN AM. BEYOND THEN, MODEL AGREEMENT BREAKS DOWN. WHILE BOTH THE GFS AND ECMWF WOULD AGREE ON SOME MORE ACTIVE WEATHER MONDAY INTO TUESDAY, THEY HAVE COMPLETELY DIFFERENT SOLUTIONS. THE GFS SHOWS ONE VERY POTENT SFC LOW DRIVEN BY A DEEP UPR TROF MOVING INTO ERN CANADA AND PUSHING A STRONG FRONT ACROSS THE STATE ON MON. THIS SOLUTION WOULD BRING ABUNDANT RAINFALL LATE SUN NIGHT THRU MON AFTERNOON, SWITCHING TO SNOW BEHIND THE FRONT AND LINGERING INTO TUE AFTERNOON. THE ECMWF IS COMPLETELY DIFFERENT, SHOWING ONE LOW DRIVEN BY A JET STREAK CROSSING THE CWA MON, AND A SECOND LOW DRIVEN BY AN UPR TROF OR CUT-OFF MOVING ACROSS ON TUE. HOWEVER, THE ECMWF HAS BEEN RATHER VARIABLE RUN-TO- RUN, WHILE THE GFS HAS BEEN A BIT MORE CONSISTENT. GIVEN THIS, AND THE FACT THAT THE CANADIAN APPEARS CLOSER TO THE GFS, ANY EDITS MADE SUN THRU TUE WERE SKEWED TOWARD THE GFS SOLUTION. && .AVIATION /06Z WEDNESDAY THROUGH SUNDAY/... NEAR TERM: VFR LATE THIS EVENING. A LLVL DECK, MVFR AND POSSIBLY EVEN IFR COULD DEVELOP AFTER MIDNIGHT AND LINGER INTO WED MORNING AS LIGHT ESE FLOW DEVELOPS. THIS DECK LOOKS LIKE IT WILL SET UP E OF THE BGR AND BHB TERMINALS. SHORT TERM: MVFR/VFR CONDITIONS ARE EXPECTED THURSDAY AND FRIDAY. && .MARINE... NEAR TERM: THE WIND AND SEAS ARE EXPECTED TO REMAIN BELOW SMALL CRAFT ADVISORY LEVELS THROUGH WEDNESDAY. SHORT TERM: HAVE USED A BLEND OF THE NAM12 AND GFS40 FOR WINDS. A SOUTHERLY FETCH WILL DEVELOP FROM THE GULF OF MAINE SOUTHWARD THURSDAY WITH WAVE HEIGHTS BUILDING TO AROUND 6 FEET/7 SECONDS. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...NONE. MARINE...NONE. && $$ NEAR TERM...CB/HEWITT/MCB SHORT TERM...MIGNONE LONG TERM...KREDENSOR AVIATION...CB/HEWITT/MIGNONE MARINE...CB/HEWITT/MIGNONE
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
349 AM EST WED DEC 9 2015 .SYNOPSIS... HIGH PRESSURE REMAINS OVER THE REGION THROUGH MIDDAY. A WEAK LOW PRESSURE SYSTEM SWINGS THROUGH THE AREA TONIGHT AND EARLY THURSDAY. HIGH PRESSURE BUILDS OVER THE AREA AGAIN BY FRIDAY AND REMAINS IN PLACE THROUGH THE COMING WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... CURRENT ANALYSIS INDICATING ~1023 MB SFC HIGH PRESSURE CENTERED ALONG THE NC/SE VA COASTAL PLAIN. FARTHER WEST...AN ELONGATED UPPER TROUGH STRETCHES FROM THE WESTERN GREAT LAKES SOUTH TO THE LOWER MS VALLEY. CURRENT IR IMAGERY SHOWS SOME HIGHER CLOUDS MOVING ACROSS NORTHERN PORTIONS OF THE FA...INCLUDING THE LOWER MD EASTERN SHORE. OF GREATER CONCERN IS THE BLANKET OF LOW CLOUDS AND FOG THAT CONTINUES TO EXPAND NORTH/EAST FROM SOUTH-CENTRAL VA EARLY THIS MORNING. ALREADY NOTING DENSE FOG (VSBY <1/4 MILE) FOR AREAS LIKE SOUTH HILL...EMPORIA...FARMVILLE...AND AHOSKIE. GOES-E FOG PRODUCT IS PICKING UP ON THIS WELL THIS MORNING AND HAS BEEN SHOWING THIS AREA OF FOG/STRATUS CONTINUING TO EXPAND. HRRR IS KEYING ON IDEA OF FOG/STRATUS SPREADING NORTH AND EAST THRU DAYBREAK AND ENCOMPASSING MUCH OF OUR VA/NC COUNTIES. THINK THAT WIDESPREAD DENSE FOG WILL BE CONFINED PRIMARILY TO THE PIEDMONT /SOUTH-CENTRAL VA COUNTIES WHERE DFA IS CURRENTLY IN EFFECT...BUT WILL CONTINUE TO MONITOR TRENDS. CERTAINLY WILL BE A GLOOMY START FOR MOST AREAS...UNTIL CLOUDS/FOG BURN OFF BY MID/LATE MORNING. FOR THE REST OF TODAY...MODELS CONTINUE TO SHOW THE UPPER TROUGH TO THE WEST TRACKING EAST ACROSS THE OH VALLEY/GREAT LAKES REGIONS...WITH A WEAK COASTAL TROUGH MOVING ACROSS SE VA/NE NC TONIGHT. HAVE CONTINUED WITH SLIGHT CHC TO LOW CHC POPS (20-30%) FOR E/SE PORTIONS OF THE FA TONIGHT. OTW...VARIABLE CLOUDS-PARTLY CLOUDY THRU TONIGHT. HIGHS TODAY IN THE MID/UPR 50S TO LOW 60S. LOWS TONIGHT IN THE UPR 30S TO MID 40S. && .SHORT TERM /THURSDAY THROUGH FRIDAY/... DRY WX AND A MOSTLY SUNNY SKY RETURNS THU IN THE WAKE OF AFOREMENTIONED SYSTEMS. HIGH TEMPS THU IN THE LOW/MID 60S. SFC HIGH PRESSURE BECOMES ESTABLISHED NEAR THE SE COAST ON FRI AS A RIDGE ALOFT BEGINS TO AMPLIFY INTO THE ERN CONUS. SWLY FLOW LEADS TO CONTINUED WARMING UNDER A MAINLY CLEAR SKY. HIGH TEMPS FRI IN THE MID/UPR 60S TO AROUND 70. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... UPPER LEVEL RIDGING SLOWLY BUILDS OVER THE MID ATLANTIC REGION FRI NIGHT THROUGH SAT NIGHT WHILE SFC HIGH PRESSURE RESIDES OFF THE SE/MID ATLANTIC STATES...RESULTING IN WARMING TEMPERATURES AND DRY CONDITIONS DURING THIS TIMEFRAME. HIGHS IN THE MID-UPPER 60S SAT... LOWS IN THE UPPER 40S FRI NIGHT AND LOWER 50S SAT NIGHT (AROUND 5 DEGREES WARMER AT THE BEACHES). 08/1200Z GFS SOLUTION COMING MORE IN LINE WITH PREVIOUS 08/0000Z ECMWF MODEL RUN. IN GENERAL... A DYNAMIC UPPER TROUGH EXITS THE DESERT SW AND INTO THE PLAINS AS SFC LOW DEVELOPS FRI NIGHT AND STRENGTHENS INTO SAT NIGHT. HOWEVER... THE LATEST 08/1200Z ECMWF HAS SUPPRESSED THE NEWD TRACK OF THE UPPER/SFC LOWS INTO THE MIDWEST (VICE THE GFS) DUE TO ITS ATTEMPT AT BECOMING MORE OF A CUTOFF LOW. THEREFORE THE EWD PROGRESSION OF ITS RESULTANT STRONG SFC COLD FRONT/ONSET OF PRECIP HAS BEEN DELAYED BY ABOUT 12-18 HOURS. AFTER COMPARING THE UPPER LEVEL JET DYNAMICS...AM LEANING SLIGHTLY MORE TWD THE GFS MODEL SOLUTION. THIS WOULD BRING THE STRENGTHENING SFC LOW INTO THE MIDWEST/GREAT LAKES BY SUN MORNING AND THE STRONG SFC COLD FRONT ACROSS THE MID ATLANTIC REGION LATE SUN NIGHT INTO THE FIRST HALF OF MON...QUICKLY PUSHING OFFSHORE BY MON NIGHT. DUE TO LONG RANGE MODEL DISCREPANCIES REGARDING TIMING AND PLACEMENT OF DYNAMIC FEATURES AND RAINFALL COVERAGE...WENT WITH A MORE BROAD BRUSHED PRECIP FORECAST AND CAPPED PRECIP WORDING TO CHANCE (NO HIGHER THAN 50 PERCENT) FOR SUN NIGHT/MON. TEMPERATURES REMAIN WARM SUN/SUN NIGHT AHEAD OF THE APPROACHING FRONT DUE TO WARM AIR ADVECTION AND BREEZY SW WINDS. HIGHS IN THE MID-UPPER 60S. LOWS IN THE 50S. TEMPERATURES ON MON/MON NIGHT WILL DEPEND ON HOW FAST PRECIP MOVES THROUGH THE AREA AND HOW FAST COLD AIR ADVECTION CAN TAKE HOLD. HIGHS FOR NOW IN THE LOW-MID 60S NW TO MID-UPPER 60S SE. WINDS SHOULD STAY BREEZY MON NIGHT AND KEEP TEMPERATURES FROM BOTTOMING OUT TO THEIR FULLEST POTENTIAL. EXPECT LOWS IN THE 40S (UPPER 30S POSSIBLE FAR NW COUNTIES). && .AVIATION /08Z WEDNESDAY THROUGH SUNDAY/... WEAK HIGH PRESSURE IS CENTERED ALONG THE MID-ATLANTIC COAST EARLY THIS MORNING. GOES SATELLITE PRODUCTS AND SURFACE OBS INDICATE A LARGE AREA OF FOG ACROSS CENTRAL NC INTO S-CENTRAL VA. PRESENTLY...THIS AREA OF FOG IS NOT DIRECTLY IMPACTING ANY TAF SITES. HOWEVER...LOCALLY DENSE FOG HAS DEVELOPED AT PHF. HIGH-RES DATA SUGGESTS THIS AREA OF FOG WILL EXPAND NE THROUGH THE EARLY MORNING HOURS...AND TIME-LAGGED RAPID REFRESH DATA DEPICTS A HIGH PROB OF IFR/LIFR DEVELOPING AT ALL TAF SITES THROUGH THE MORNING. THE CURRENT FORECAST BEGINS IFR IN THE 08-10Z TIME-FRAME...WITH POTENTIALLY WIDESPREAD DENSE FOG DEVELOPING BY 10-12Z. THE HIGH GRADUALLY MOVES OFFSHORE TODAY...WHICH WILL ALLOW FOR AN 8-10KT SOUTHERLY WIND TO DEVELOP BY ~16Z. VSBY SHOULD BE IMPROVING BY THIS POINT...BUT THE SOUTHERLY WIND SHOULD FULLY RETURN CONDITIONS TO VFR. A WEAK BOUNDARY WILL CROSS THE REGION LATE TONIGHT...BUT MOISTURE IS LIMITED AND FORCING WILL BE WEAK. OTHERWISE...EXPECT MAINLY VFR CONDITIONS THURSDAY THROUGH SUNDAY WITH HIGH PRESSURE ACROSS THE REGION. THE ONLY EXCEPTION WILL BE THE POTENTIAL FOR EARLY MORNING FOG. && .MARINE... BENIGN CONDITIONS ARE EXPECTED ACROSS THE MARINE AREA THROUGH SUNDAY AS HIGH PRESSURE PREVAILS ACROSS THE REGION. WEAK HIGH PRESSURE WILL GRADUALLY SLIDE OFFSHORE TODAY WITH A 5-10KT S WIND DEVELOPING. A WEAK TROUGH WILL SLIDE ACROSS THE AREA LATE TONIGHT INTO EARLY THURSDAY...PRODUCING NOT MUCH MORE THAN SUBTLE WIND SHIFT...BEFORE S FLOW RESUMES BY AFTERNOON AS HIGH PRESSURE DEVELOPS ALONG THE SOUTHEAST COAST. HIGH PRESSURE THEN EXPANDS AND BECOMES ANCHORED OFF THE SOUTHEAST COAST THURSDAY NIGHT THROUGH SUNDAY. THIS WILL PRODUCE SW FLOW AOB 15KT...WITH 2-3FT SEAS...AND 1- 2FT WAVES IN THE BAY. A COLD FRONT APPROACHES FROM THE W SUNDAY NIGHT...WITH THE LATEST DATA BRINGING THE FRONT ACROSS THE COAST MONDAY EVENING. THIS FRONT WILL BRING THE NEXT CHC OF SCA CONDITIONS. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...NONE. NC...DENSE FOG ADVISORY UNTIL 10 AM EST THIS MORNING FOR NCZ012. VA...DENSE FOG ADVISORY UNTIL 10 AM EST THIS MORNING FOR VAZ060-061- 065>068-079-080-087-088-092. MARINE...NONE. && $$ SYNOPSIS...JDM NEAR TERM...JDM SHORT TERM...JDM LONG TERM...BMD AVIATION...AJZ MARINE...AJZ
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1034 PM CST TUE DEC 8 2015 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 342 PM CST TUE DEC 8 2015 GOOD PV ANOMALY WITH DRYING NOTED IN WATER VAPOR HAS HELPED FORCE A NICE BAND OF LIGHT RAIN ACROSS ERN MN/WRN WI TODAY. NORTH OF THE PV BOOT...THE COMBINATION OF FGEN IN THE H85-H7 LAYER AND ISENTROPIC LIFT ON THE 295K SFC HAVE PROVIDED THE FORCING FOR THE BAND OF RAIN WE SEE OUT THERE THIS AFTERNOON. THE HRRR HAS HAD A PRETTY GOOD HANDLE ON THIS RAIN...SO FOLLOWED IT FOR SHIPPING THIS BAND OF RAIN OUT OF THE EAST END OF THE MPX CWA BETWEEN 3Z AND 6Z. THIS WILL LIKELY BE IT FOR ANY MEANINGFUL PRECIP...THOUGH A FEW SPRINKLES WILL BE POSSIBLE UNTIL THE MAIN UPPER TROUGH AND ASSOCIATED SFC THROUGH CURRENTLY ENTERING WRN MN MOVE THROUGH. HOWEVER...THIS WAVE LOOKS TO LACK DEEP MOISTURE LIKE THE LEAD WAVE HAS...SO CONCENTRATED ANY MENTIONABLE POPS ON THE ERN WAVE. FOR TONIGHT...THE MAIN PLAYER TO WHAT WILL HAPPEN WITH TEMPERATURES AND THE POTENTIAL FOR FOG/STRATUS WILL BE THE NARROW STRIP OF CLEARING THAT IS STRADDLING THE WRN DAKOTAS BORDER. THIS CLEARING WILL WORK FROM WEST TO EAST ACROSS THE MPX AREA TONIGHT. DEPENDING ON WHEN THE CLEARING ARRIVES AND HOW LONG IT PERSISTS...COULD EASILY SEE LOWS A FEW DEGREES COOLER THAN WHAT WE CURRENTLY HAVE...ESPECIALLY ACROSS CENTRAL MN. THERE WILL ALSO BE THE POTENTIAL TO DEVELOP FOG/LOW STRATUS. HOWEVER...WITH SFC WINDS EXPECTED TO REMAIN UP IN THE 4-8KT RANGE BEHIND THE TROUGH...LIKELY MEANS OUR MAIN ISSUE FOR TONIGHT WOULD BE THE POTENTIAL FOR VERY LOW STRATUS AS OPPOSED TO FOG. THE HRRR DEVELOPS LOW STRATUS/FOG LATE TONIGHT OVER ERN MN/WRN WI...WHICH GIVEN THE CURRENT RAIN WOULD MAKE THE MOST SENSE FOR SEEING STRATUS/FOG IF WE ARE GOING TO SEE IT. FOR WEDNESDAY...ZONAL FLOW ALOFT WILL MEAN MORE MID/UPPER LEVEL CLOUDS...BUT ALSO THE RETURN OF VERY MILD AIR FROM THE CENTRAL PLAINS. BOUNDARY LAYER WINDS TOMORROW WILL BE FROM THE SW...WHICH IS A FAVORABLE WARMING DIRECTION. AS A RESULT...BOOSTED HIGHS SEVERAL DEGREES DOWNSTREAM OF THE BUFFALO RIDGE...WHERE WE ARE NOW ANTICIPATING HIGHS TO REACH INTO THE LOW TO MID 50S...WITH HIGHS AROUND 40 WITH THE REMNANT SNOWPACK OVER CENTRAL MN AND MID/UPPER 40S ELSEWHERE...THOUGH THIS COULD BE WARMER OUTSIDE OF THE REMNANT SNOW COVER. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 342 PM CST TUE DEC 8 2015 THE PATTERN WILL CONTINUE BECOMING MORE ACTIVE DURING THE LONG TERM. THE FIRST IN A SERIES OF SYSTEMS TO WATCH WILL BE TRACKING EASTWARD ALONG THE CANADIAN BORDER WEDNESDAY NIGHT AND THURSDAY. MODELS REMAIN IN FAIRLY GOOD AGREEMENT WITH THIS SYSTEM...WITH THE EXCEPTION OF THE EURO WHICH CONTINUES TO TRACK ON THE SOUTHERN EDGE OF THE ENVELOPE. THE MAJORITY OF THE CWA SHOULD BE DRY...WITH PRECIPITATION LIKELY TO OCCUR ALONG AND NORTH OF THE STORM TRACK. REDUCED POPS SOME...BUT MAINTAINED AT LEAST SOME MENTIONABLE POPS ACROSS THE ENTIRE CWA. HIGHEST POPS ARE CONFINED TO CENTRAL MN WHERE HIGH CHC OR LOW END LIKELIES CONTINUE. TO THE SOUTH OF THE TRACK...THE DRY SLOT SHOULD HELP CLEAR THE CLOUDS THURSDAY AFTERNOON ACROSS SRN MN AND WRN WI. STRONGEST CAA WILL LAG BEHIND THE SYSTEM...AND IT COULD GET RATHER MILD DEPENDING ON THE AMOUNT OF SUN. CANNOT RULE OUT LOWER 50S ACROSS SRN MN AND INTO WRN WI. WINDS WILL BE QUITE GUSTY WITH THE PASSAGE OF THE NEGATIVELY TILTED TROUGH...PARTICULARLY IF THE BOUNDARY LAYER DESTABILIZES WITH EITHER STRONGER CAA ALOFT...OR HEATING WITH SUN. THE DEVELOPING TROUGH ACROSS THE WESTERN U.S. THURSDAY INTO FRIDAY WILL PLAY A BIG ROLE IN THE REST OF THE LONG TERM FORECAST. ENERGY WILL BEGIN EJECTING OUT IN PIECES THURSDAY NIGHT WITH A LEADING WAVE ARRIVING LATE FRIDAY. THIS MAY BRING A SMALL CHANCE FOR PRECIPITATION...BUT IT DOES NOT HAVE THE TROPICAL MOISTURE IT WOULD NEED TO PRODUCE ANYTHING SIGNIFICANT. THE MAIN PLAYER WILL ROUND THE BASE OF THE TROUGH OVER THE SOUTHWESTERN U.S. SATURDAY. THERE ARE REALLY ONLY TWO LIKELY SCENARIOS THAT WILL PLAY OUT. THE FIRST ONE IS A PHASED SYSTEM WITH THE NORTHERN STREAM THAT RESULTS IN A ROBUST SURFACE CYCLONE WHICH TRACKS NORTH NORTHEAST FROM THE SOUTHERN PLAINS INTO THE WESTERN GREAT LAKES. THIS SCENARIO WOULD BRING A LOT OF MOISTURE WITH IT NORTHWARD...WITH A MATURE EXTRATROPICAL CYCLONE BY SUNDAY MORNING SOMEWHERE OVER THE UPPER MISSISSIPPI VALLEY. SUCH A TRACK IS A LIKELY HEAVY SNOW PRODUCER FOR US. THE OPERATIONAL GFS AND MANY OF ITS ENSEMBLES...THE CANADIAN...AND THE FORMER RUNS OF THE ECMWF INDICATED THIS AS A FAVORED OPTION. THE OTHER SCENARIO IS WHAT THE NEW ECMWF HAS REVERTED TO AND FEATURES THE UPPER LOW CLOSING OFF FROM THE NORTHERN STREAM WHICH RESULTS IN A LESS DEVELOPED...SLOW MOVING SOUTHERN CYCLONE AND LITTLE OR NO PRECIPITATION FOR US. AT THIS POINT EITHER SCENARIO IS POSSIBLE...BUT PREFER THE FIRST SOLUTION WHICH HAD STRONG SUPPORT OVERNIGHT. WILL AWAIT FOR FUTURE RUNS TO DETERMINE ANY MEANINGFUL TREND. FOLLOWING THE PASSAGE OF THAT SYSTEM IS ANOTHER ORIGINATING FROM THE NEXT TROUGH OVER THE WESTERN U.S. MODEL CONSISTENCY HAS NOT BEEN THE BEST WITH THIS ONE...LIKELY DUE TO ERRORS ASSOCIATED WITH ITS PREDECESSOR. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 1033 PM CST TUE DEC 8 2015 GIVEN THE RAIN AND LIGHT WIND...WE ARE SEEING A FEW POCKETS OF FOG IN EASTERN MN AND WESTERN WI. WE ARE A LITTLE CONCERNED THAT CLEARING COULD ALLOW THE FOG TO EXPAND LATE TONIGHT. WE ALSO EXPECT A SLIGHT INCREASE IN WIND...WHICH WOULD HELP INHIBIT FOG FORMATION. GIVEN THE UNCERTAINTY...WE`LL HAVE TO MONITOR THE VISIBILITY TRENDS AND UPDATE ACCORDINGLY. WE DO THINK THE FOG WILL GRADUALLY PUSH EAST WITH TIME...SO KRNH COULD ACTUALLY CLEAR BEFORE SUNRISE. KMSP... WE INCLUDED A TEMPO FOR LIGHT FOG EARLY TONIGHT WITH MVFR VISIBILITY. THIS MIGHT NOT HAPPEN. THERE IS A LITTLE WIND OUT THERE AND THE AIRPORT IS TYPICALLY HARD TO FOG IN...BUT THE HUMIDITY IS CLOSE TO 100% THIS EVENING AND THE WIND HAS BEEN NEAR CALM AT TIMES...SO WHEN THE SKY CLEARS IT WOULD ONLY TAKE A SMALL AMOUNT OF COOLING TO START FORMING FOG. THE GOOD NEWS...IF IT DOES FORM...IT SHOULD MOVE ABOUT BEFORE THE MORNING RUSH. /OUTLOOK FOR KMSP/ THU...VFR WITH MVFR/-RA POSSIBLE. WIND W AT 10G20 KTS. FRI...VFR. WINDS ESE 5-10 KTS. SAT...VFR WITH MVFR POSSIBLE. WINDS NNW 5-10 KTS. && .MPX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. && $$ SHORT TERM...MPG LONG TERM...BORGHOFF AVIATION...CLF
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1238 AM CST WED DEC 9 2015 .UPDATE... ISSUED AT 1232 AM CST WED DEC 9 2015 A FEW MINOR UPDATES WERE MADE TO PRECIP CHANCES FOR THIS UPDATE. THE LATEST SHORT-TERM MODELS INDICATE ANY AREA OF SCATTERED RAIN SHOWERS OVER CANADA WILL CONTINUE TO DEVELOP AND PUSH ACROSS WESTERN AND CENTRAL NORTH DAKOTA THROUGH THE OVERNIGHT AND EARLY MORNING HOURS. RADAR INDICATES RECENT DEVELOPMENT ACROSS WESTERN AND NORTH CENTRAL NORTH DAKOTA. THEREFORE...INCREASED COVERAGE OF PRECIP CHANCES. UPDATE ISSUED AT 925 PM CST TUE DEC 8 2015 BASED ON THE LATEST RADAR INFORMATION AND CONSSHORT GUIDANCE HAVE ADJUSTED THE POPS A BIT FURTHER SOUTH. HRRR STILL KEEPS THE PRECIP FURTHER NORTH THAN CONSSHORT BUT WILL TREND CLOSER TO CONSSHORT. UPDATE ISSUED AT 627 PM CST TUE DEC 8 2015 WILL CONTINUE TO FOLLOW THE LATEST HRRR MODEL THAT KEEPS THE PRECIP ACROSS THE NORTH TONIGHT. THE CONSSHORT GUIDANCE LOOKS A BIT TOO FAR SOUTH AND TOO WET AT THIS TIME. LIKE THE CURRENT POPS WITH JUST A SLIGHT CHANCE OF RAIN THIS EVENING BUT A THREAT FRO SOME FREEZING RAIN NORTH CENTRAL...OVER THE TURTLE MOUNTAINS TOWARDS MIDNIGHT. OTHERWISE UPDATED THE CURRENT CONDITIONS. && .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 250 PM CST TUE DEC 8 2015 VERY WARM WEATHER IS EXPECTED WEDNESDAY IN MEAN ZONAL FLOW ALOFT. ANOTHER BATCH OF VERY MILD AIR ORIGINATING OVER THE PACIFIC OCEAN WILL SURGE EASTWARD INTO THE NORTHERN PLAINS BY WEDNESDAY AHEAD OF A 500-MB SHORTWAVE CRASHING INTO THE NORTHERN ROCKIES. THE 12 UTC MODEL GUIDANCE CALLS FOR 850-MB TEMPERATURES TO RISE INTO THE +10 TO +12 C RANGE OVER SOUTHWESTERN ND BY WEDNESDAY...AND WITH MEAN WESTERLY LOW-LEVEL THROUGH AT LEAST EARLY AFTERNOON...HIGHS WILL SOAR TO NEAR-RECORD LEVELS IN MANY AREAS. WE UTILIZED 12 UTC BIAS- CORRECTED MOS TO BUILD THE HIGH TEMPERATURE FORECAST WEDNESDAY... WHICH CALLS FOR HIGHS RANGING FROM 50 AT JAMESTOWN TO THE LOWER 60S IN SOUTHWESTERN ND. THE CURRENT DAILY RECORD HIGHS OF 56 F AT WILLISTON AND 60 F AT DICKINSON COULD BE TIED OR BROKEN. EXPECTED HIGH-LEVEL CLOUDS AND A LATE-DAY TURN TOWARD MORE SOUTHERLY WINDS IN THE BOUNDARY LAYER KEPT US FROM ADVERTISING EVEN WARMER HIGHS. OTHERWISE...WE DO HAVE A SLIGHT CHANCE OF LIGHT RAIN OR FREEZING RAIN OVER NORTHWEST AND NORTH CENTRAL ND AFTER 06 UTC TONIGHT AND CONTINUING INTO EARLY WEDNESDAY MORNING. THAT MENTION IS TIED TO THE APPROACHING MID-LEVEL WARM FRONT...BUT THERE IS LITTLE SIGNAL OF MOISTURE IN THE DETERMINISTIC MODEL OUTPUT AND IN MANY LOCALES SURFACE TEMPERATURES WILL RISE ABOVE 32 F OVERNIGHT...SO THE AREA WITH A RISK OF LIGHT FREEZING RAIN WILL LIKELY BE SMALL IN SPACE AND TIME...AND CENTERED MAINLY FROM BOTTINEAU TOWARD ROLLA. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 250 PM CST TUE DEC 8 2015 STRONG WINDS AND POSSIBLE MIXED PRECIPITATION HIGHLIGHT THE EARLY PORTION OF THE EXTENDED PERIOD WITH A COOLING TREND AS WE HEAD INTO THE UPCOMING WEEKEND. A STRONG S/WV TROUGH MOVES EAST ACROSS THE NORTHERN PLAINS WEDNESDAY NIGHT. MODELS ARE STILL INDICATING ALL RAIN ACROSS THE SOUTHERN TWO THIRDS OF THE STATE WHERE AIR TEMPERATURES REMAINS ABOVE FREEZING...WITH A WINTRY MIX POSSIBLE FAR NORTH WHERE TEMPERATURES WILL BE CLOSER TO FREEZING OR BELOW. STRONG CAA IN THE WAKE OF WED NIGHTS WAVE WILL SEE DAYTIME TEMPERATURES 10-20 DEGREES COLDER THURSDAY COMPARED TO WEDNESDAY...WITH ALSO WRAP AROUND RAIN OR SNOW SURGING SOUTH AND EAST ACROSS THE STATE. STRONG WINDS REMAIN A CONCERN LATE WED NIGHT INTO THURSDAY BEHIND THE SFC LOW WITH STRONG PRESSURE RISES DEVELOPING EAST ACROSS THE DAKOTAS. MODELS REMAIN OUT OF SYNC AS FAR AS THE LOW PRESSURE PLACEMENT AND TIMING OF WINDS...AS WELL AS MIXING LAYER HEIGHTS AND THUS POTENTIAL WIND GUSTS. WE OPTED TO HOLD OFF ON ANY HEADLINES AND LET THE MID SHIFT TONIGHT RELOOK LATEST 00Z GUIDANCE WHICH HOPEFULLY NARROWS THINGS DOWN BETTER. YET ANOTHER POTENT S/WV TROUGH MOVES ACROSS THE REGION LATE THURSDAY NIGHT INTO FRIDAY. THIS TIME THE ATMOSPHERIC PROFILE WILL BE COLD ENOUGH FOR ALL SNOW. THIS FEATURE WILL BE MORE INTERESTING WITH A MORE DEFINED SFC TROUGH AXIS EXTENDING INTO OUR AREA ALONG WITH STRONGER UPPER LEVEL JET DYNAMICS. WILL MONITOR THIS PERIOD CLOSE OVER THE NEXT DAY OR TWO WITH NEAR ADVISORY ACCUMULATIONS STILL POSSIBLE. HOWEVER...LATEST MODELS ARE MORE PROGRESSIVE SO FORECAST SNOW AMOUNTS HAVE BEEN REDUCED TO MORE IN THE 1-2 INCH RANGE. REINFORCED SHOT OF COLDER AIR FOLLOWS FOR THE WEEKEND...WHICH ALSO LOOKS DRY. WILL NEED TO MONITOR MODELS CLOSELY FOR EARLY TO MID NEXT WEEK AS STRONG ENERGY MOVES INTO THE PACIFIC NORTHWEST LATE THIS WEEKEND...AND WHICH MAY EVENTUALLY IMPACT THE NORTHERN PLAINS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 1232 AM CST WED DEC 9 2015 VFR AT ALL TAF SITES THROUGH THE TAF PERIOD. THERE IS A SLIGHT CHANCE THAT TERMINALS COULD SEE SOME VERY LIGHT RAIN...HOWEVER...DUE TO THE SCATTERED NATURE OF LIGHT RAIN CONFIDENCE WASN`T HIGH ENOUGH AT ANY INDIVIDUAL TERMINAL TO MENTION IN THE TAF. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...AJ SHORT TERM...CJS LONG TERM...NH AVIATION...AJ
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
247 AM EST WED DEC 9 2015 .SYNOPSIS... A HIGH STAGNANT RIDGE OF HIGH PRESSURE WILL BRING YET ANOTHER FOGGY MORNING TO A LARGE PART OF CENTRAL PA. A SERIES OF LOW PRESSURE SYSTEMS WILL TRACK WELL WEST OF PA LATE IN THE WEEK AS AN ANOMALOUS UPPER RIDGE BUILDS ALONG THE EAST COAST. TEMPERATURES WILL BE WARMER THAN NORMAL FOR MUCH OF THE NEXT WEEK OR TWO. && .NEAR TERM /UNTIL 10 AM THIS MORNING/... AREAS OF DENSE...FREEZING FOG BLANKETING THE DEEPER VALLEYS IN THE CENTRAL MTNS REGION...WILL GRADUALLY EXPAND OUTWARD EARLY TODAY...CREATING A FAIRLY LARGE AREA OF VERY HAZARDOUS TRAVEL. TEMPS AND DEWPOINTS ARE NEARLY IDENTICAL TO LAST NIGHT AT THIS TIME IN MANY LOCATIONS. HOWEVER...SLIGHTLY HIGHER MOISTURE IS BEING INJECTED/ADVECTED NWD WITHIN A FEW TENS OF MB AGL /AND THROUGHOUT A LARGE DEPTH OF THE PERSISTENT SFC-BASED INVERSION/. THE DENSE FREEZING FOG ENTRENCHED IN THE CENTRAL MTNS AND SUSQ WEST BRANCH VALLEYS WILL JUST SLOWLY LIFT A FEW TO SVRL HUNDRED FEET LATE THIS MORNING INTO THIS AFTERNOON...POSSIBLY REQUIRED AN ADJUSTMENT/EXTENSION/TRANSITION BACK TO A PLAIN OLD DENSE FOG ADVISORY IN THOSE LOCATIONS. THE SATURATED LAYER WILL DEEPEN UP TO NEARLY 2 KFT AGL INTO AT LEAST EARLY THIS AFTERNOON...POSSIBLY ENOUGH TO PRODUCE SOME LIGHT DRIZZLE /PER LATEST SREF/NAM AND GFS SOUNDINGS. HRRR AND RAP DATA IS SLIGHTLY MORE OPTIMISTIC WITH THE MOISTURE DEPTH DECREASING BY LATE THIS MORNING AND THE T/TD SPREAD INCREASING A FEW DEG C...WHICH WOULD CAUSE EARLIER DISSIPATION OF THE DENSE FOG. INCREASED AND EXPANDED CLOUD COVER TO PAINT MORE OF A CLOUDY LATE MORNING AND EARLY AFTERNOON THROUGHOUT THE CENTRAL MTNS. MAX TEMPS SHOULD ONLY REACH THE MID 40S ACRS MUCH OF THE CENTRAL AND NRN MTNS...WHILE NEARING THE 50F MARK ACROSS THE SE ZONES. && .SHORT TERM /10 AM THIS MORNING THROUGH 6 PM THURSDAY/... THIS MORNING`S FOG WILL BE SLOW TO DISSIPATE...BUT INCREASING BOUNDARY LAYER FLOW AHEAD OF ANOTHER SHEARING UPPER WAVE AND AMPLIFYING UPPER FLOW MAY FINALLY HELP SCOUR THINGS OUT LATE THIS AFTERNOON /MORE THAN WE/VE SEEN IN A FEW DAYS/. SOME BREAKS OF MID TO LATE AFTERNOON SUN AND WARMING TEMPS ALOFT SHOULD PUSH READINGS TO BTWN 45-50F ACROSS THE REGION BY AFTN. MOISTURE INCREASES SUFFICIENTLY AHEAD OF APPROACHING SHORTWAVE TO INTRODUCE A CHANCE OF SHOWERS BY THIS EVENING ACROSS THE NW MTNS. ELSEWHERE...NO MENTION OF PRECIP OUTSIDE OF THE PREVIOUSLY NOTED PATCHY DRIZZLE /MAINLY ON THE SOUTH-SE FACING SLOPES OF THE RIDGES. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... THE MAIN STORY FOR THE LONG TERM IS UNSEASONABLY MILD WEATHER...AS WE EXPECT TEMPERATURES ARE EXPECTED TO REMAIN ABOVE- NORMAL RIGHT INTO EARLY NEXT WEEK. AS FOR PRECIPITATION...A WEAKENING TROUGH OF LOW PRESSURE COULD BRING A FEW SHOWERS ACROSS CENTRAL PA WED NIGHT INTO THU...WITH ANOTHER TROUGH PROVIDING A SLIGHT CHC FOR SHOWERS ACROSS MAINLY THE NORTH AND WEST THU NITE INTO FRI. SATURDAY INTO SUNDAY WILL SEE A SIGNIFICANT UPPER-LEVEL RIDGE BUILD OVER THE EAST COAST. INCREASINGLY SOUTHERLY FLOW SHOULD BRING IN EVEN MILDER TEMPERATURES THIS WEEKEND...WITH SOME LOCATIONS SEEING AFTERNOON HIGHS APPROACHING 20 DEGREES ABOVE- NORMAL. A MORE SIGNIFICANT STORM SYSTEM WILL TRACK ACROSS THE GREAT LAKES AND INTO NEW ENGLAND MONDAY INTO TUESDAY...DRAGGING A COLD FRONT ACROSS CENTRAL PA. THIS SYSTEM WILL BE ACCOMPANIED BY A PERIOD OF SHOWERY WEATHER...AND FOLLOWED BY A COOL-DOWN BY THE MIDDLE OF NEXT WEEK. && .AVIATION /08Z WEDNESDAY THROUGH SUNDAY/... HIGH PRESSURE ALONG THE ATLC COAST WILL PROVIDE GENERALLY CLEAR SKIES AND LIGHT WINDS THIS EVENING...ALLOWING REDEVELOPMENT OR THICKENING OF LOW FOG/LOW LEVEL CIGS ESPECIALLY AT LOCATIONS THAT REMAINED LOW TODAY. AREA OF MID CLOUDS WILL SPREAD WEST TO EAST OVERNIGHT AHEAD OF WEATHER SYSTEM OVER THE PLAINS. THIS MAY HELP TO DISRUPT LOWER CONDS...AT LEAST TEMPORARILY OVERNIGHT. SLOW IMPROVEMENT IS EXPECTED WEDNESDAY AS SFC WINDS INCREASE AHD OF THE APPROACHING WEATHER SYSTEM. THIS SYSTEM WILL BRING SHOWERS TO THE REGION WED NIGHT. OUTLOOK... TUE NIGHT-WED NIGHT...CHANCE FOR MVFR CIGS. THU-FRI...MVFR POSS NW. SAT...MVFR WITH CHC SHRA. SUN...VFR. && .CTP WATCHES/WARNINGS/ADVISORIES... FREEZING FOG ADVISORY UNTIL 10 AM EST THIS MORNING FOR PAZ012- 017>019-025>028-034-035-041-045-046-049-050. && $$ SYNOPSIS...LAMBERT NEAR TERM...LAMBERT/FITZGERALD SHORT TERM...LAMBERT/FITZGERALD LONG TERM...EVANEGO AVIATION...DEVOIR/GARTNER
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
348 AM PST WED DEC 9 2015 ...WIDESPREAD RAIN AND LOCALLY GUSTY CONDITIONS ON THURSDAY... .SYNOPSIS....LOOK FOR RAIN TO MOVE TO THE NORTH BAY LATER TODAY AND THEN ACROSS OUR ENTIRE REGION ON THURSDAY AS A FRONT MOVES THROUGH. GUSTY WINDS WILL ACCOMPANY ITS APPROACH AND PASSAGE. SHOWERS AND POSSIBLE THUNDERSTORMS ARE THEN EXPECTED THURSDAY NIGHT INTO FRIDAY AS A COOL AND UNSTABLE AIR MASS MOVES IN. MORE WIDESPREAD RAIN IS SLATED FOR LATE SATURDAY THROUGH SUNDAY. && .DISCUSSION...AS OF 3:00 AM PST WEDNESDAY...HIGH CLOUDS STREAMING ACROSS OUR AREA THIS MORNING HAS HELPED TO KEEP TEMPERATURES WARMER COMPARED TO YESTERDAY WITH MANY SPOTS 5 TO 10 DEGREES AHEAD. IN ADDITION, SOME LOCATIONS HAVE SEEN FOG WITH VISIBILITIES DOWN TO LESS THAN 1/2 A MILE ALTHOUGH MOST OBSERVATIONS ARE NOW REPORTING VISIBILITIES GREATER THAN 3 MILES. RAIN WILL ADVANCE TO THE NORTH BAY LATER THIS MORNING AS THE WEAK RIDGE OVER US YESTERDAY FLATTENS AND MOVES TO THE EAST. 500 MB FLOW WILL BEGIN TO SAG TO THE SOUTH ALLOWING MOISTURE BACK TO OUR AREA. KBHX RADAR IS PICKING UP ECHOS ABOUT TO ENTER THE MENDO COUNTY COAST WITH HRRR SHOWING THE LEADING EDGE GETTING TO THE SONOMA COAST BY MID-MORNING TODAY. RAIN WILL SLOWLY CONTINUE TO SPREAD TO THE SOUTH WITH A LITTLE LIGHT RAIN POSSIBLE INTO THE SF BAY REGION BY THE AFTERNOON. THIS ROUND OF RAIN IS A PRECURSOR TO THE BIGGER EVENT AS A COLD FRONT WITH MODERATELY MOIST AIR (PW VALUES OF UP TO 1.20") ADVANCES FROM THE NORTHWEST LATE TONIGHT AND CONTINUES INTO THURSDAY. WIDESPREAD RAINFALL WILL MOVE INTO THE NORTH BAY LATE TONIGHT THEN DOWN TO SF BAY REGION AROUND THE MORNING RUSH. THE FRONT WILL CONTINUE TO THE MONTEREY BAY REGION AROUND BY EARLY AFTERNOON. DURING THE FRONTAL PASSAGE, RAIN COULD BE MODERATE TO HEAVY AT TIMES ALTHOUGH THE DURATION SHOULD BE FAIRLY SHORT. AFTER A BREAK IN THE PRECIPITATION, SHOWERS WILL MOVE IN FROM THE NORTHWEST AS THE ATMOSPHERE BECOMES MUCH MORE UNSTABLE. THUNDERSTORMS WITH SMALL HAIL WILL ALSO BE POSSIBLE ESPECIALLY BY TOMORROW NIGHT AS THE MOST FAVORED DYNAMICS MOVE ACROSS OUR AREA. SHOWERS LOOK LIKELY INTO FRIDAY AFTERNOON WITH DRY WEATHER EXPECTED TO RETURN BY FRIDAY EVENING. MODELS ARE SUGGESTING THAT RAINFALL FROM THE SHOWERS MAY END UP BEING GREATER THAN THE RAIN DURING THE FRONTAL PASSAGE. RAINFALL TOTALS THROUGH FRIDAY MORNING ARE EXPECTED TO BE 1-2" FOR THE NORTH BAY MOUNTAINS, UP TO AN INCH FOR COASTAL RANGES OF SANTA CRUZ AND MONTEREY COUNTIES, AND 1/3" TO 2/3" FOR MANY METRO AREAS. SNOW LEVELS WILL DROP DOWN TO UNDER 4000 FEET BY FRIDAY MORNING WITH MINOR ACCUMULATIONS EXPECTED FOR OUR HIGHEST PEAKS. WIND WILL ALSO BE A FACTOR WITH INCREASING WEST TO SOUTHWEST WINDS EXPECTED TONIGHT INTO THURSDAY. MODELS CONTINUE TO FOCUS THE HIGHEST SPEEDS OVER THE NORTH BAY MOUNTAINS, SO WILL KEEP THE ADVISORY GOING FOR THAT REGION. MOST LOCATIONS COULD SEE SPEEDS OF 15 TO 25 MPH WITH GUSTS TO 35 MPH. SIMILAR TO TODAY, RAIN WILL GENERALLY BE CONFINED TO THE NORTH BAY ON SATURDAY BEFORE SPREADING AGAIN ACROSS THE ENTIRE CWA AS ANOTHER COLD FRONT MOVES THROUGH ON SUNDAY. ECMWF HAS BEEN TRENDING WETTER WHICH IS MORE IN LINE WITH THE GFS SOLUTIONS OVER THE PAST COUPLE OF DAYS. IN ADDITION, PW VALUES ARE NOW FORECAST TO APPROACH 1.10" WHICH IS AN INCREASE OF AROUND .2" FROM YESTERDAY. THEREFORE, RAINFALL AMOUNTS MAY HAVE THE POTENTIAL TO REACH VALUES SIMILAR TO WHAT WE ARE EXPECTING THURSDAY INTO FRIDAY. POPS WERE INCREASED FOR SATURDAY NIGHT THROUGH SUNDAY. LONGER RANGE GUIDANCE FROM CPC ALSO FAVORS ABOVE NORMAL RAINFALL FOR NEXT WEEK SUGGESTING A CONTINUED ACTIVE PATTERN. && .AVIATION...AS OF 03:50 AM PST WEDNESDAY... LOW TO MEDIUM CONFIDENCE FORECAST. HIGH CLOUDS SPILLING ACROSS CALIFORNIA THIS MORNING ARE OBSCURING VIEW OF THE CRITICAL LOWER LEVEL CLOUDS. OBS STATIONS PRIMARILY REPORTING VFR TO MVFR CIGS... WITH PATCHY VLIFR IN SALINAS AND NORTH BAY VALLEYS. EXPECTING CIGS TO BOUNCE AROUND THROUGH THE TAF PERIOD... WITH GRADUALLY DETERIORATING CIGS AS SFC BOUNDARY APPROACHES AT THE END OF TAF PERIOD. CIGS LOOK TO BE CONTAINED BETWEEN 1600-4000 FT AGL FOR THIS MORNINGS AVIATION PUSHES THEN DROPPING TO 1000-2000 FT OR LOWER FOR TONIGHT/EARLY THURSDAY. LIGHT PRECIP POSBL LATER TODAY IN NORTH BAY. WINDS PREDOMINATELY LIGHT... THEN INCREASING TOWARDS END OF TAF PERIOD. VICINITY OF KSFO...OSCILLATING VFR TO MVFR CIGS WITH CLOUDS 1600-4000 FT AGL. WINDS INCREASING STEADILY AFTER 00Z THU. WINDS GUSTING TO 30-35KT 12-18Z THU. SFO BRIDGE APPROACH...SIMILAR TO KSFO. MONTEREY BAY AREA TERMINALS...VFR EXCEPT WHERE THERE IS PATCHY FOG. LIGHT WINDS. MVFR TO IFR CIGS POSBL AFTER 02Z THU. && .MARINE...AS OF 3:00 AM PST WEDNESDAY...A STRONG STORM SYSTEM WILL CAUSE WINDS TO INCREASE LATE WEDNESDAY INTO THURSDAY PRODUCING HAZARDOUS CONDITIONS. A VERY LARGE LONG PERIOD SWELL WILL ARRIVE THURSDAY AND FRIDAY PRODUCING HAZARDOUS CONDITIONS NEAR THE IMMEDIATE COASTLINE...ESPECIALLY ALONG COASTAL REEFS AND SAND BARS AS WELL AS ACROSS THE SAN FRANCISCO BAR. && .BEACHES...AS OF 3:00 AM PST WEDNESDAY...ANOTHER LARGE SWELL WILL IMPACT THE COASTAL WATERS LATE TONIGHT THROUGH FRIDAY. SOME OF THE MODEL GUIDANCE SUGGESTS THIS COULD BE THE BIGGEST SWELL OF THE SEASON THUS FAR. LATEST FORECAST WILL HAVE SWELLS OVER 20 FEET IN THE OUTER WATERS AND 15 TO 20 FEET IN THE INNER WATERS. THE PERIOD IS GREATER THAN 16 SECONDS. THAT BEING SAID...WAVES BREAKING AT THE COAST COULD EASILY EXCEED 20 FEET AND OVER 30 FEET AT DEEP WATER BREAKS. THESE LARGE BREAKING WAVES WILL PUSH WATER WELL UP ONTO THE BEACH POSSIBLY WASHING PEOPLE FROM THE BEACH INTO THE SEA. LARGE SNEAKER WAVES WILL ALSO BE POSSIBLE ON STEEP BEACHES SUCH AS CARMEL RIVER BEACH AND MONTARA BEACH. PLEASE DO NOT CLIMB ON ROCKS OR JETTIES ALONG THE COAST SINCE THESE AREAS WILL ALSO BE PRONE TO SNEAKER WAVES. THESE WAVES WILL ARRIVE IN SETS WITH LONG LULLS BETWEEN WAVE ACTIVITY WHICH COULD GIVE BEACH VISITORS A FALSE SENSE OF SECURITY...DRAWING THEM CLOSER TO THE WATERS EDGE. REMEMBER TO NEVER TURN YOUR BACK TO THE WATER AND ALWAYS KEEP AN EYE OUT FOR RAPIDLY APPROACHING WAVES. && .MTR WATCHES/WARNINGS/ADVISORIES... .TDAY...NONE. && $$ PUBLIC FORECAST: BELL AVIATION: DRP MARINE: DRP VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO FOLLOW US ON FACEBOOK AND TWITTER AT: WWW.FACEBOOK.COM/NWSBAYAREA WWW.TWITTER.COM/NWSBAYAREA
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
300 AM PST WED DEC 9 2015 ...WIDESPREAD RAIN AND LOCALLY GUSTY CONDITIONS ON THURSDAY... .SYNOPSIS....LOOK FOR RAIN TO MOVE TO THE NORTH BAY LATER TODAY AND THEN ACROSS OUR ENTIRE REGION ON THURSDAY AS A FRONT MOVES THROUGH. GUSTY WINDS WILL ACCOMPANY ITS APPROACH AND PASSAGE. SHOWERS AND POSSIBLE THUNDERSTORMS ARE THEN EXPECTED THURSDAY NIGHT INTO FRIDAY AS A COOL AND UNSTABLE AIR MASS MOVES IN. MORE WIDESPREAD RAIN IS SLATED FOR LATE SATURDAY THROUGH SUNDAY. && .DISCUSSION...AS OF 3:00 AM PST WEDNESDAY...HIGH CLOUDS STREAMING ACROSS OUR AREA THIS MORNING HAS HELPED TO KEEP TEMPERATURES WARMER COMPARED TO YESTERDAY WITH MANY SPOTS 5 TO 10 DEGREES AHEAD. IN ADDITION, SOME LOCATIONS HAVE SEEN FOG WITH VISIBILITIES DOWN TO LESS THAN 1/2 A MILE ALTHOUGH MOST OBSERVATIONS ARE NOW REPORTING VISIBILITIES GREATER THAN 3 MILES. RAIN WILL ADVANCE TO THE NORTH BAY LATER THIS MORNING AS THE WEAK RIDGE OVER US YESTERDAY FLATTENS AND MOVES TO THE EAST. 500 MB FLOW WILL BEGIN TO SAG TO THE SOUTH ALLOWING MOISTURE BACK TO OUR AREA. KBHX RADAR IS PICKING UP ECHOS ABOUT TO ENTER THE MENDO COUNTY COAST WITH HRRR SHOWING THE LEADING EDGE GETTING TO THE SONOMA COAST BY MID-MORNING TODAY. RAIN WILL SLOWLY CONTINUE TO SPREAD TO THE SOUTH WITH A LITTLE LIGHT RAIN POSSIBLE INTO THE SF BAY REGION BY THE AFTERNOON. THIS ROUND OF RAIN IS A PRECURSOR TO THE BIGGER EVENT AS A COLD FRONT WITH MODERATELY MOIST AIR (PW VALUES OF UP TO 1.20") ADVANCES FROM THE NORTHWEST LATE TONIGHT AND CONTINUES INTO THURSDAY. WIDESPREAD RAINFALL WILL MOVE INTO THE NORTH BAY LATE TONIGHT THEN DOWN TO SF BAY REGION AROUND THE MORNING RUSH. THE FRONT WILL CONTINUE TO THE MONTEREY BAY REGION AROUND BY EARLY AFTERNOON. DURING THE FRONTAL PASSAGE, RAIN COULD BE MODERATE TO HEAVY AT TIMES ALTHOUGH THE DURATION SHOULD BE FAIRLY SHORT. AFTER A BREAK IN THE PRECIPITATION, SHOWERS WILL MOVE IN FROM THE NORTHWEST AS THE ATMOSPHERE BECOMES MUCH MORE UNSTABLE. THUNDERSTORMS WITH SMALL HAIL WILL ALSO BE POSSIBLE ESPECIALLY BY TONIGHT AS THE MOST FAVORED DYNAMICS MOVE ACROSS OUR AREA. SHOWERS LOOK LIKELY INTO FRIDAY AFTERNOON WITH DRY WEATHER EXPECTED TO RETURN BY FRIDAY EVENING. MODELS ARE SUGGESTING THAT RAINFALL FROM THE SHOWERS MAY END UP BEING GREATER THAN THE RAIN DURING THE FRONTAL PASSAGE. RAINFALL TOTALS THROUGH FRIDAY MORNING ARE EXPECTED TO BE 1-2" FOR THE NORTH BAY MOUNTAINS, UP TO AN INCH FOR COASTAL RANGES OF SANTA CRUZ AND MONTEREY COUNTIES, AND 1/3" TO 2/3" FOR MANY METRO AREAS. SNOW LEVELS WILL DROP DOWN TO UNDER 4000 FEET BY FRIDAY MORNING WITH MINOR ACCUMULATIONS EXPECTED FOR OUR HIGHEST PEAKS. WIND WILL ALSO BE A FACTOR WITH INCREASING WEST TO SOUTHWEST WINDS EXPECTED TONIGHT INTO THURSDAY. MODELS CONTINUE TO FOCUS THE HIGHEST SPEEDS OVER THE NORTH BAY MOUNTAINS, SO WILL KEEP THE ADVISORY GOING FOR THAT REGION. MOST LOCATIONS COULD SEE SPEEDS OF 15 TO 25 MPH WITH GUSTS TO 35 MPH. SIMILAR TO TODAY, RAIN WILL GENERALLY BE CONFINED TO THE NORTH BAY ON SATURDAY BEFORE SPREADING AGAIN ACROSS THE ENTIRE CWA AS ANOTHER COLD FRONT MOVES THROUGH ON SUNDAY. ECMWF HAS BEEN TRENDING WETTER WHICH IS MORE IN LINE WITH THE GFS SOLUTIONS OVER THE PAST COUPLE OF DAYS. IN ADDITION, PW VALUES ARE NOW FORECAST TO APPROACH 1.10" WHICH IS AN INCREASE OF AROUND .2" FROM YESTERDAY. THEREFORE, RAINFALL AMOUNTS MAY HAVE THE POTENTIAL TO REACH VALUES SIMILAR TO WHAT WE ARE EXPECTING THURSDAY INTO FRIDAY. POPS WERE INCREASED FOR SATURDAY NIGHT THROUGH SUNDAY. LONGER RANGE GUIDANCE FROM CPC ALSO FAVORS ABOVE NORMAL RAINFALL FOR NEXT WEEK SUGGESTING A CONTINUED ACTIVE PATTERN. && .AVIATION...AS OF 10:26 PM PST TUESDAY...MVFR/VFR WITH LOCALIZED IFR CONDITIONS CONTINUING OVERNIGHT DUE TO A MIX OF CLOUDS AND PATCHY FOG. KCCR AS WELL AS KSNS REPORTING 1/4 MILE VSBY IN FOG. LIGHT RAIN WILL DEVELOP OVER THE NORTH BAY LATE TONIGHT AND CONTINUE THROUGH WEDNESDAY. LIGHT RAIN ALSO POSSIBLE OVER THE REST OF THE BAY AREA WEDNESDAY. VICINITY OF KSFO...MVFR CIGS. LOWER CONFIDENCE IFR CIGS 09Z-18Z TIMEFRAME. LIGHT RAIN POSSIBLE WEDNESDAY. SFO BRIDGE APPROACH...SIMILAR TO KSFO. MONTEREY BAY AREA TERMINALS...PATCHY IFR AROUND THE AREA DUE TO FOG TONIGHT. LIGHT WINDS. && .MARINE...AS OF 3:00 AM PST WEDNESDAY...A STRONG STORM SYSTEM WILL CAUSE WINDS TO INCREASE LATE WEDNESDAY INTO THURSDAY PRODUCING HAZARDOUS CONDITIONS. A VERY LARGE LONG PERIOD SWELL WILL ARRIVE THURSDAY AND FRIDAY PRODUCING HAZARDOUS CONDITIONS NEAR THE IMMEDIATE COASTLINE...ESPECIALLY ALONG COASTAL REEFS AND SAND BARS AS WELL AS ACROSS THE SAN FRANCISCO BAR. && .BEACHES...AS OF 3:00 AM PST WEDNESDAY...ANOTHER LARGE SWELL WILL IMPACT THE COASTAL WATERS LATE TONIGHT THROUGH FRIDAY. SOME OF THE MODEL GUIDANCE SUGGESTS THIS COULD BE THE BIGGEST SWELL OF THE SEASON THUS FAR. LATEST FORECAST WILL HAVE SWELLS OVER 20 FEET IN THE OUTER WATERS AND 15 TO 20 FEET IN THE INNER WATERS. THE PERIOD IS GREATER THAN 16 SECONDS. THAT BEING SAID...WAVES BREAKING AT THE COAST COULD EASILY EXCEED 20 FEET AND OVER 30 FEET AT DEEP WATER BREAKS. THESE LARGE BREAKING WAVES WILL PUSH WATER WELL UP ONTO THE BEACH POSSIBLY WASHING PEOPLE FROM THE BEACH INTO THE SEA. LARGE SNEAKER WAVES WILL ALSO BE POSSIBLE ON STEEP BEACHES SUCH AS CARMEL RIVER BEACH AND MONTARA BEACH. PLEASE DO NOT CLIMB ON ROCKS OR JETTIES ALONG THE COAST SINCE THESE AREAS WILL ALSO BE PRONE TO SNEAKER WAVES. THESE WAVES WILL ARRIVE IN SETS WITH LONG LULLS BETWEEN WAVE ACTIVITY WHICH COULD GIVE BEACH VISITORS A FALSE SENSE OF SECURITY...DRAWING THEM CLOSER TO THE WATERS EDGE. REMEMBER TO NEVER TURN YOUR BACK TO THE WATER AND ALWAYS KEEP AN EYE OUT FOR RAPIDLY APPROACHING WAVES. && .MTR WATCHES/WARNINGS/ADVISORIES... .TDAY...NONE. && $$ PUBLIC FORECAST: BELL AVIATION: CANEPA MARINE: DRP BEACHES: BELL/MM VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO FOLLOW US ON FACEBOOK AND TWITTER AT: WWW.FACEBOOK.COM/NWSBAYAREA WWW.TWITTER.COM/NWSBAYAREA
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1049 AM EST WED DEC 9 2015 .SYNOPSIS... HIGH PRESSURE WILL GRADUALLY RELAX ITS GRIP ON THE REGION TODAY. A SERIES OF WEAK FRONTS WILL TRACK WELL WEST OF PA LATE IN THE WEEK AS AN ANOMALOUS UPPER RIDGE BUILDS ALONG THE EAST COAST. TEMPERATURES WILL BE WARMER THAN NORMAL FOR MUCH OF THE NEXT WEEK OR TWO. && .NEAR TERM /UNTIL 2 PM THIS AFTERNOON/... AREAS OF DENSE...FREEZING FOG BLANKETING THE DEEPER VALLEYS IN THE CENTRAL MTNS REGION...WILL GRADUALLY BURN OFF THROUGH MID DAY. THE EXCEPTION WILL BE THE LOWER SUSQ WHERE THE EXPERIMENTAL HRRR SHOWS THE LOW CLOUDS HANGING ON WELL INTO THE DAY. HAVE EXTENDED THE ADVISORY FOR FOG THROUGH NOON TO COVER THE SLOW BURN OFF. OTHER THAN POCKETS OF PATCHY DRIZZLE/FREEZING DRIZZLE...THE CHANCES FOR RAIN WILL REMAIN VERY LOW UNTIL LATER TODAY OR THIS EVENING AS SHOWERS ASSOCIATED WITH A DYING COLD FRONT BEGIN TO THREATEN MY FAR NWRN ZONES. && .SHORT TERM /2 PM THIS AFTERNOON THROUGH 6 PM THURSDAY/... THE MORNING FOG WILL BE SLOW TO DISSIPATE...BUT INCREASING BOUNDARY LAYER FLOW AHEAD OF ANOTHER SHEARING UPPER WAVE AND AMPLIFYING UPPER FLOW MAY FINALLY HELP SCOUR THINGS OUT LATE THIS AFTERNOON /MORE THAN WE`VE SEEN IN A FEW DAYS/. SOME BREAKS OF MID TO LATE AFTERNOON SUN ARE POSSIBLE...THANKS IN PART TO WARMING TEMPS ALOFT AND INCREASING SOUTHERLY FLOW. MAX TEMPS SHOULD ONLY REACH THE MID 40S ACRS MUCH OF THE CENTRAL AND NRN MTNS...WHILE NEARING THE 50F MARK ACROSS THE SE ZONES. THE MERCURY MAY HAVE DIFFICULTY RISING ABOVE 40F OVER THE MTNS NORTH OF KIPT. MOISTURE INCREASES SUFFICIENTLY AHEAD OF APPROACHING SHORTWAVE AND WEAK SFC CFRONT TO INTRODUCE A CHANCE OF SHOWERS BY THIS EVENING ACROSS THE NW MTNS. ELSEWHERE...NO MENTION OF PRECIP OUTSIDE OF THE PREVIOUSLY NOTED PATCHY DRIZZLE /MAINLY ON THE SOUTH-SE FACING SLOPES OF THE RIDGES/. WILL HAVE TO CLOSELY MONITOR THE REGION NEAR AND TO THE EAST OF THE SUSQ MAINSTEM WHERE ABUNDANT LLVL MOISTURE COULD ONCE AGAIN STAY TRAPPED BENEATH A FAIRLY STRONG SFC BASED INVERSION...AND LEAD TO WIDESPREAD LOW CLOUDS AND AREAS OF DENSE FOG. ON THE POSITIVE SIDE...AT LEAST MIN TEMPS EARLY THURSDAY WILL BE IN THE MID TO UPPER 30S...NEGATING THE CHC FOR FREEZING FOG. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... THE MAIN STORY FOR THE LONG TERM CONTINUES TO BE UNSEASONABLY MILD WEATHER...AS WE EXPECT TEMPERATURES ARE EXPECTED TO REMAIN ABOVE- NORMAL RIGHT INTO EARLY NEXT WEEK. AS FOR PRECIPITATION...A WEAKENING TROUGH OF LOW PRESSURE COULD BRING A FEW SHOWERS ACROSS CENTRAL PA WED NIGHT INTO THU...WITH ANOTHER TROUGH PROVIDING A SLIGHT CHC FOR SHOWERS ACROSS MAINLY THE NORTH AND WEST THU NITE INTO FRI. SATURDAY INTO SUNDAY WILL SEE A SIGNIFICANT UPPER-LEVEL RIDGE BUILD OVER THE EAST COAST. INCREASINGLY SOUTHERLY FLOW SHOULD BRING IN EVEN MILDER TEMPERATURES THIS WEEKEND...WITH SOME LOCATIONS SEEING AFTERNOON HIGHS APPROACHING 20 DEGREES ABOVE- NORMAL. A MORE SIGNIFICANT STORM SYSTEM WILL TRACK ACROSS THE GREAT LAKES AND INTO NEW ENGLAND MONDAY INTO TUESDAY...DRAGGING A COLD FRONT ACROSS CENTRAL PA. THIS SYSTEM WILL BE ACCOMPANIED BY A PERIOD OF SHOWERY WEATHER...AND FOLLOWED BY A COOL-DOWN BY THE MIDDLE OF NEXT WEEK. && .AVIATION /16Z WEDNESDAY THROUGH SUNDAY/... WITH THE EXCEPTION OF BFD/JST...LOW CLOUDS AND DENSE FOG CONTINUE TO PLAGUE CENTRAL AND EASTERN PA TERMINALS. HRRR SHOWS THE LOW CLOUDS OVER CENTRAL PA FINALLY BEGINNING TO BREAK UP BY EARLY AFTERNOON...WITH THE LOW CLOUDS HANGING TOUGH OVER THE LOWER SUSQ VALLEY. WINDS WILL GENERALLY BE LIGHT...WITH SPEEDS OVER THE NW MOUNTAINS INCREASING TO AROUND 8-10KT THIS AFTERNOON AHEAD OF AN APPROACHING WEAK TROUGH THAT WILL LIFT THROUGH TONIGHT. WEAK TROUGH LIFTING SW-NE OVER THE REGION TONIGHT WILL BRING AN INFLUX OF LOW-LEVEL MOISTURE TO WESTERN AND CENTRAL PA. THIS WILL BRING A SOLID AREA OF CIG RESTRICTIONS TO WESTERN SECTIONS ALONG WITH SOME LIGHT RAIN SHOWERS. OVER MY SOUTHEASTERN TERMINALS THIS MOISTURE UNDER THE RETREATING INVERSION LOOKS TO KEEP LOW CLOUDS AND AREAS OF FOG LOCKED IN. OUTLOOK... THU...MORNING FOG/RESTRICTIONS. IMPROVEMENT IN THE AFT...WITH MVFR CIGS NW HALF AND VFR SE. FRI...AREAS OF MORNING FOG. THEN MAINLY VFR. SAT-SUN...MVFR WITH CHC SHRA NW HALF. MAINLY VFR SE. && .CTP WATCHES/WARNINGS/ADVISORIES... FREEZING FOG ADVISORY UNTIL NOON EST TODAY FOR PAZ012-017>019- 025>028-034-035-041-045-046-049-050. && $$ SYNOPSIS...LA CORTE/LAMBERT NEAR TERM...LA CORTE/LAMBERT SHORT TERM...LAMBERT LONG TERM...EVANEGO AVIATION...RXR
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1032 AM EST WED DEC 9 2015 .SYNOPSIS... HIGH PRESSURE WILL GRADUALLY RELAX ITS GRIP ON THE REGION TODAY. A SERIES OF WEAK FRONTS WILL TRACK WELL WEST OF PA LATE IN THE WEEK AS AN ANOMALOUS UPPER RIDGE BUILDS ALONG THE EAST COAST. TEMPERATURES WILL BE WARMER THAN NORMAL FOR MUCH OF THE NEXT WEEK OR TWO. && .NEAR TERM /UNTIL 2 PM THIS AFTERNOON/... AREAS OF DENSE...FREEZING FOG BLANKETING THE DEEPER VALLEYS IN THE CENTRAL MTNS REGION...WILL GRADUALLY BURN OFF THROUGH MID DAY. THE EXCEPTION WILL BE THE LOWER SUSQ WHERE THE EXPERIMENTAL HRRR SHOWS THE LOW CLOUDS HANGING ON WELL INTO THE DAY. HAVE EXTENDED THE ADVISORY FOR FOG THROUGH NOON TO COVER THE SLOW BURN OFF. OTHER THAN POCKETS OF PATCHY DRIZZLE/FREEZING DRIZZLE...THE CHANCES FOR RAIN WILL REMAIN VERY LOW UNTIL LATER TODAY OR THIS EVENING AS SHOWERS ASSOCIATED WITH A DYING COLD FRONT BEGIN TO THREATEN MY FAR NWRN ZONES. && .SHORT TERM /2 PM THIS AFTERNOON THROUGH 6 PM THURSDAY/... THE MORNING FOG WILL BE SLOW TO DISSIPATE...BUT INCREASING BOUNDARY LAYER FLOW AHEAD OF ANOTHER SHEARING UPPER WAVE AND AMPLIFYING UPPER FLOW MAY FINALLY HELP SCOUR THINGS OUT LATE THIS AFTERNOON /MORE THAN WE`VE SEEN IN A FEW DAYS/. SOME BREAKS OF MID TO LATE AFTERNOON SUN ARE POSSIBLE...THANKS IN PART TO WARMING TEMPS ALOFT AND INCREASING SOUTHERLY FLOW. MAX TEMPS SHOULD ONLY REACH THE MID 40S ACRS MUCH OF THE CENTRAL AND NRN MTNS...WHILE NEARING THE 50F MARK ACROSS THE SE ZONES. THE MERCURY MAY HAVE DIFFICULTY RISING ABOVE 40F OVER THE MTNS NORTH OF KIPT. MOISTURE INCREASES SUFFICIENTLY AHEAD OF APPROACHING SHORTWAVE AND WEAK SFC CFRONT TO INTRODUCE A CHANCE OF SHOWERS BY THIS EVENING ACROSS THE NW MTNS. ELSEWHERE...NO MENTION OF PRECIP OUTSIDE OF THE PREVIOUSLY NOTED PATCHY DRIZZLE /MAINLY ON THE SOUTH-SE FACING SLOPES OF THE RIDGES/. WILL HAVE TO CLOSELY MONITOR THE REGION NEAR AND TO THE EAST OF THE SUSQ MAINSTEM WHERE ABUNDANT LLVL MOISTURE COULD ONCE AGAIN STAY TRAPPED BENEATH A FAIRLY STRONG SFC BASED INVERSION...AND LEAD TO WIDESPREAD LOW CLOUDS AND AREAS OF DENSE FOG. ON THE POSITIVE SIDE...AT LEAST MIN TEMPS EARLY THURSDAY WILL BE IN THE MID TO UPPER 30S...NEGATING THE CHC FOR FREEZING FOG. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... THE MAIN STORY FOR THE LONG TERM CONTINUES TO BE UNSEASONABLY MILD WEATHER...AS WE EXPECT TEMPERATURES ARE EXPECTED TO REMAIN ABOVE- NORMAL RIGHT INTO EARLY NEXT WEEK. AS FOR PRECIPITATION...A WEAKENING TROUGH OF LOW PRESSURE COULD BRING A FEW SHOWERS ACROSS CENTRAL PA WED NIGHT INTO THU...WITH ANOTHER TROUGH PROVIDING A SLIGHT CHC FOR SHOWERS ACROSS MAINLY THE NORTH AND WEST THU NITE INTO FRI. SATURDAY INTO SUNDAY WILL SEE A SIGNIFICANT UPPER-LEVEL RIDGE BUILD OVER THE EAST COAST. INCREASINGLY SOUTHERLY FLOW SHOULD BRING IN EVEN MILDER TEMPERATURES THIS WEEKEND...WITH SOME LOCATIONS SEEING AFTERNOON HIGHS APPROACHING 20 DEGREES ABOVE- NORMAL. A MORE SIGNIFICANT STORM SYSTEM WILL TRACK ACROSS THE GREAT LAKES AND INTO NEW ENGLAND MONDAY INTO TUESDAY...DRAGGING A COLD FRONT ACROSS CENTRAL PA. THIS SYSTEM WILL BE ACCOMPANIED BY A PERIOD OF SHOWERY WEATHER...AND FOLLOWED BY A COOL-DOWN BY THE MIDDLE OF NEXT WEEK. && .AVIATION /15Z WEDNESDAY THROUGH SUNDAY/... WITH THE EXCEPTION OF BFD/JST...LOW CLOUDS AND DENSE FOG CONTINUE TO PLAGUE CENTRAL AND EASTERN PA TERMINALS. HRRR SHOWS THE LOW CLOUDS OVER CENTRAL PA FINALLY BEGINNING TO BREAK UP BY EARLY AFTERNOON...WITH THE LOW CLOUDS HANGING TOUGH OVER THE LOWER SUSQ VALLEY. WINDS WILL GENERALLY BE LIGHT...WITH SPEEDS OVER THE NW MOUNTAINS INCREASING TO AROUND 8-10KT THIS AFTERNOON AHEAD OF AN APPROACHING WEAK TROUGH THAT WILL LIFT THROUGH TONIGHT. WEAK TROUGH LIFTING SW-NE OVER THE REGION TONIGHT WILL BRING AN INFLUX OF LOW-LEVEL MOISTURE TO WESTERN AND CENTRAL PA. THIS WILL BRING A SOLID AREA OF CIG RESTRICTIONS TO WESTERN SECTIONS ALONG WITH SOME LIGHT RAIN SHOWERS. OVER MY SOUTHEASTERN TERMINALS ...THIS MOISTURE UNDER THE RETREATING INVERSION LOOKS TO KEEP LOW CLOUDS AND AREAS OF FOG LOCKED IN. OUTLOOK... THU...MORNING FOG/RESTRICTIONS. IMPROVEMENT IN THE AFT...WITH MVFR CIGS NW HALF AND VFR SE. FRI...AREAS OF MORNING FOG. THEN MAINLY VFR. SAT-SUN...MVFR WITH CHC SHRA NW HALF. MAINLY VFR SE. && .CTP WATCHES/WARNINGS/ADVISORIES... FREEZING FOG ADVISORY UNTIL NOON EST TODAY FOR PAZ012-017>019- 025>028-034-035-041-045-046-049-050. && $$ SYNOPSIS...LA CORTE/LAMBERT NEAR TERM...LA CORTE/LAMBERT SHORT TERM...LAMBERT LONG TERM...EVANEGO AVIATION...LA CORTE/RXR
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
719 AM EST WED DEC 9 2015 .SYNOPSIS... A HIGH STAGNANT RIDGE OF HIGH PRESSURE WILL BRING YET ANOTHER FOGGY MORNING TO A LARGE PART OF CENTRAL PA. A SERIES OF LOW PRESSURE SYSTEMS WILL TRACK WELL WEST OF PA LATE IN THE WEEK AS AN ANOMALOUS UPPER RIDGE BUILDS ALONG THE EAST COAST. TEMPERATURES WILL BE WARMER THAN NORMAL FOR MUCH OF THE NEXT WEEK OR TWO. && .NEAR TERM /UNTIL 2 PM THIS AFTERNOON/... AREAS OF DENSE...FREEZING FOG BLANKETING THE DEEPER VALLEYS IN THE CENTRAL MTNS REGION...WILL GRADUALLY EXPAND OUTWARD EARLY TODAY...CREATING A FAIRLY LARGE AREA OF VERY HAZARDOUS TRAVEL. 10Z TEMPS AND DEWPOINTS /IN THE MID 20S TO AROUND 30F/ ARE NEARLY IDENTICAL IN MANY LOCATIONS TO THOSE EARLY TUESDAY. HOWEVER... SLIGHTLY HIGHER MOISTURE IS BEING INJECTED/ADVECTED NWD WITHIN A FEW TENS OF MB AGL /AND THROUGHOUT A LARGE DEPTH OF THE PERSISTENT SFC- BASED INVERSION/. THE DENSE FREEZING FOG ENTRENCHED IN THE CENTRAL MTNS AND SUSQ WEST BRANCH VALLEYS WILL JUST SLOWLY LIFT A FEW TO SVRL HUNDRED FEET LATE THIS MORNING INTO THIS AFTERNOON...POSSIBLY REQUIRED AN ADJUSTMENT/EXTENSION/TRANSITION BACK TO A PLAIN OLD DENSE FOG ADVISORY IN THOSE LOCATIONS. THE SATURATED LAYER WILL DEEPEN UP TO NEARLY 2 KFT AGL INTO AT LEAST EARLY THIS AFTERNOON...POSSIBLY ENOUGH TO PRODUCE SOME LIGHT DRIZZLE /PER LATEST SREF/NAM AND GFS SOUNDINGS. HRRR AND RAP DATA IS SLIGHTLY MORE OPTIMISTIC WITH THE MOISTURE DEPTH DECREASING BY LATE THIS MORNING AND THE T/TD SPREAD INCREASING A FEW DEG C...WHICH WOULD CAUSE EARLIER DISSIPATION OF THE DENSE FOG. INCREASED AND EXPANDED CLOUD COVER TO PAINT MORE OF A CLOUDY LATE MORNING AND EARLY AFTERNOON THROUGHOUT THE CENTRAL MTNS. && .SHORT TERM /2 PM THIS AFTERNOON THROUGH 6 PM THURSDAY/... THE MORNING FOG WILL BE SLOW TO DISSIPATE...BUT INCREASING BOUNDARY LAYER FLOW AHEAD OF ANOTHER SHEARING UPPER WAVE AND AMPLIFYING UPPER FLOW MAY FINALLY HELP SCOUR THINGS OUT LATE THIS AFTERNOON /MORE THAN WE/VE SEEN IN A FEW DAYS/. SOME BREAKS OF MID TO LATE AFTERNOON SUN ARE POSSIBLE...THANKS IN PART TO WARMING TEMPS ALOFT AND INCREASING SOUTHERLY FLOW. MAX TEMPS SHOULD ONLY REACH THE MID 40S ACRS MUCH OF THE CENTRAL AND NRN MTNS...WHILE NEARING THE 50F MARK ACROSS THE SE ZONES. THE MERCURY MAY HAVE DIFFICULTY RISING ABOVE 40F OVER THE MTNS NORTH OF KIPT. MOISTURE INCREASES SUFFICIENTLY AHEAD OF APPROACHING SHORTWAVE AND WEAK SFC CFRONT TO INTRODUCE A CHANCE OF SHOWERS BY THIS EVENING ACROSS THE NW MTNS. ELSEWHERE...NO MENTION OF PRECIP OUTSIDE OF THE PREVIOUSLY NOTED PATCHY DRIZZLE /MAINLY ON THE SOUTH-SE FACING SLOPES OF THE RIDGES/. WILL HAVE TO CLOSELY MONITOR THE REGION NEAR AND TO THE EAST OF THE SUSQ MAINSTEM WHERE ABUNDANT LLVL MOISTURE COULD ONCE AGAIN STAY TRAPPED BENEATH A FAIRLY STRONG SFC BASED INVERSION...AND LEAD TO WIDESPREAD LOW CLOUDS AND AREAS OF DENSE FOG. ON THE POSTITIVE SIDE...AT LEAST MIN TEMPS EARLY THURSDAY WILL BE IN THE MID TO UPPER 30S...NEGATING THE CHC FOR FREEZING FOG. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... THE MAIN STORY FOR THE LONG TERM CONTINUES TO BE UNSEASONABLY MILD WEATHER...AS WE EXPECT TEMPERATURES ARE EXPECTED TO REMAIN ABOVE- NORMAL RIGHT INTO EARLY NEXT WEEK. AS FOR PRECIPITATION...A WEAKENING TROUGH OF LOW PRESSURE COULD BRING A FEW SHOWERS ACROSS CENTRAL PA WED NIGHT INTO THU...WITH ANOTHER TROUGH PROVIDING A SLIGHT CHC FOR SHOWERS ACROSS MAINLY THE NORTH AND WEST THU NITE INTO FRI. SATURDAY INTO SUNDAY WILL SEE A SIGNIFICANT UPPER-LEVEL RIDGE BUILD OVER THE EAST COAST. INCREASINGLY SOUTHERLY FLOW SHOULD BRING IN EVEN MILDER TEMPERATURES THIS WEEKEND...WITH SOME LOCATIONS SEEING AFTERNOON HIGHS APPROACHING 20 DEGREES ABOVE- NORMAL. A MORE SIGNIFICANT STORM SYSTEM WILL TRACK ACROSS THE GREAT LAKES AND INTO NEW ENGLAND MONDAY INTO TUESDAY...DRAGGING A COLD FRONT ACROSS CENTRAL PA. THIS SYSTEM WILL BE ACCOMPANIED BY A PERIOD OF SHOWERY WEATHER...AND FOLLOWED BY A COOL-DOWN BY THE MIDDLE OF NEXT WEEK. && .AVIATION /12Z WEDNESDAY THROUGH SUNDAY/... EVEN THOUGH HIGH PRESSURE AREA DRIFTING EASTWARD...LOW LEVEL INVERSION REMAINS IN PLACE BRINGING ANOTHER MORNING OF VLIFR TO IFR RESTRICTIONS TO MANY TERMINALS. THICKEST FOG OVERNIGHT HAS IMPACTED KAOO-KUNV WITH NEAR ZERO VISIBILITIES. LOW CIGS OVER KIPT SHOULD LOWER TO THE SURFACE AROUND SUNRISE BRINGING SEVERAL HOURS OF DENSE FOG THERE TOO. NO LOW CLOUDS OVER THE SE AT KMDT-KLNS AND UP OVER THE NW IN KBFD...BUT A SHORT-LIVED PERIOD OF VIS REDUCTIONS LIKELY DEVELOPING THERE AS WELL THROUGH ABOUT 15Z. OVER CENTRAL AREAS...FOG WILL BE LONGER LIVED - POTENTIALLY LASTING INTO THE EARLY AFTERNOON WITH CIG RESTRICTIONS LIKELY PERSISTING THROUGH THE DAY. WINDS WILL GENERALLY BE LIGHT...WITH SPEEDS OVER THE NW MTNS INCREASING TO AROUND 8-10KTS OVER THE NW MTNS THIS AFTERNOON AHEAD OF AN APPROACHING WEAK TROUGH THAT WILL LIFT THROUGH TONIGHT. WEAK TROUGH LIFTING SW-NE OVER THE REGION TONIGHT WILL BRING AN INFLUX OF LOW-LEVEL MOISTURE TO CENTRAL PA. THIS WILL BRING A SOLID AREA OF CIG RESTRICTIONS TO WESTERN SECTIONS ALONG WITH SOME LIGHT RAIN SHOWERS. OVER CENTRAL AND EAST...THIS INFUSION OF LL MOISTURE UNDER THE RETREATING INVERSION LOOKS TO AGAIN PRODUCE AREAS OF POTENTIALLY DENSE FOG AND LOW CIGS...ESP FROM KIPT- KMDT/KLNS. NAM AND SREF BOTH INDICATING THIS PRETTY STRONGLY AND MODEL SOUNDINGS SUPPORT THIS LINE OF THINKING. OUTLOOK... THU...MORNING FOG/RESTRICTIONS. IMPROVEMENT IN THE AFT...WITH MVFR CIGS NW HALF AND VFR SE. FRI...AREAS OF MORNING FOG. THEN MAINLY VFR. SAT-SUN...MVFR WITH CHC SHRA NW HALF. MAINLY VFR SE. && .CTP WATCHES/WARNINGS/ADVISORIES... FREEZING FOG ADVISORY UNTIL 10 AM EST THIS MORNING FOR PAZ012- 017>019-025>028-034-035-041-045-046-049-050. && $$ SYNOPSIS...LAMBERT NEAR TERM...LAMBERT SHORT TERM...LAMBERT LONG TERM...EVANEGO AVIATION...RXR
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
542 AM EST WED DEC 9 2015 .SYNOPSIS... A HIGH STAGNANT RIDGE OF HIGH PRESSURE WILL BRING YET ANOTHER FOGGY MORNING TO A LARGE PART OF CENTRAL PA. A SERIES OF LOW PRESSURE SYSTEMS WILL TRACK WELL WEST OF PA LATE IN THE WEEK AS AN ANOMALOUS UPPER RIDGE BUILDS ALONG THE EAST COAST. TEMPERATURES WILL BE WARMER THAN NORMAL FOR MUCH OF THE NEXT WEEK OR TWO. && .NEAR TERM /UNTIL 2 PM THIS AFTERNOON/... AREAS OF DENSE...FREEZING FOG BLANKETING THE DEEPER VALLEYS IN THE CENTRAL MTNS REGION...WILL GRADUALLY EXPAND OUTWARD EARLY TODAY...CREATING A FAIRLY LARGE AREA OF VERY HAZARDOUS TRAVEL. 10Z TEMPS AND DEWPOINTS /IN THE MID 20S TO AROUND 30F/ ARE NEARLY IDENTICAL IN MANY LOCATIONS TO THOSE EARLY TUESDAY. HOWEVER... SLIGHTLY HIGHER MOISTURE IS BEING INJECTED/ADVECTED NWD WITHIN A FEW TENS OF MB AGL /AND THROUGHOUT A LARGE DEPTH OF THE PERSISTENT SFC- BASED INVERSION/. THE DENSE FREEZING FOG ENTRENCHED IN THE CENTRAL MTNS AND SUSQ WEST BRANCH VALLEYS WILL JUST SLOWLY LIFT A FEW TO SVRL HUNDRED FEET LATE THIS MORNING INTO THIS AFTERNOON...POSSIBLY REQUIRED AN ADJUSTMENT/EXTENSION/TRANSITION BACK TO A PLAIN OLD DENSE FOG ADVISORY IN THOSE LOCATIONS. THE SATURATED LAYER WILL DEEPEN UP TO NEARLY 2 KFT AGL INTO AT LEAST EARLY THIS AFTERNOON...POSSIBLY ENOUGH TO PRODUCE SOME LIGHT DRIZZLE /PER LATEST SREF/NAM AND GFS SOUNDINGS. HRRR AND RAP DATA IS SLIGHTLY MORE OPTIMISTIC WITH THE MOISTURE DEPTH DECREASING BY LATE THIS MORNING AND THE T/TD SPREAD INCREASING A FEW DEG C...WHICH WOULD CAUSE EARLIER DISSIPATION OF THE DENSE FOG. INCREASED AND EXPANDED CLOUD COVER TO PAINT MORE OF A CLOUDY LATE MORNING AND EARLY AFTERNOON THROUGHOUT THE CENTRAL MTNS. && .SHORT TERM /2 PM THIS AFTERNOON THROUGH 6 PM THURSDAY/... THE MORNING FOG WILL BE SLOW TO DISSIPATE...BUT INCREASING BOUNDARY LAYER FLOW AHEAD OF ANOTHER SHEARING UPPER WAVE AND AMPLIFYING UPPER FLOW MAY FINALLY HELP SCOUR THINGS OUT LATE THIS AFTERNOON /MORE THAN WE/VE SEEN IN A FEW DAYS/. SOME BREAKS OF MID TO LATE AFTERNOON SUN ARE POSSIBLE...THANKS IN PART TO WARMING TEMPS ALOFT AND INCREASING SOUTHERLY FLOW. MAX TEMPS SHOULD ONLY REACH THE MID 40S ACRS MUCH OF THE CENTRAL AND NRN MTNS...WHILE NEARING THE 50F MARK ACROSS THE SE ZONES. THE MERCURY MAY HAVE DIFFICULTY RISING ABOVE 40F OVER THE MTNS NORTH OF KIPT. MOISTURE INCREASES SUFFICIENTLY AHEAD OF APPROACHING SHORTWAVE AND WEAK SFC CFRONT TO INTRODUCE A CHANCE OF SHOWERS BY THIS EVENING ACROSS THE NW MTNS. ELSEWHERE...NO MENTION OF PRECIP OUTSIDE OF THE PREVIOUSLY NOTED PATCHY DRIZZLE /MAINLY ON THE SOUTH-SE FACING SLOPES OF THE RIDGES/. WILL HAVE TO CLOSELY MONITOR THE REGION NEAR AND TO THE EAST OF THE SUSQ MAINSTEM WHERE ABUNDANT LLVL MOISTURE COULD ONCE AGAIN STAY TRAPPED BENEATH A FAIRLY STRONG SFC BASED INVERSION...AND LEAD TO WIDESPREAD LOW CLOUDS AND AREAS OF DENSE FOG. ON THE POSTITIVE SIDE...AT LEAST MIN TEMPS EARLY THURSDAY WILL BE IN THE MID TO UPPER 30S...NEGATING THE CHC FOR FREEZING FOG. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... THE MAIN STORY FOR THE LONG TERM CONTINUES TO BE UNSEASONABLY MILD WEATHER...AS WE EXPECT TEMPERATURES ARE EXPECTED TO REMAIN ABOVE- NORMAL RIGHT INTO EARLY NEXT WEEK. AS FOR PRECIPITATION...A WEAKENING TROUGH OF LOW PRESSURE COULD BRING A FEW SHOWERS ACROSS CENTRAL PA WED NIGHT INTO THU...WITH ANOTHER TROUGH PROVIDING A SLIGHT CHC FOR SHOWERS ACROSS MAINLY THE NORTH AND WEST THU NITE INTO FRI. SATURDAY INTO SUNDAY WILL SEE A SIGNIFICANT UPPER-LEVEL RIDGE BUILD OVER THE EAST COAST. INCREASINGLY SOUTHERLY FLOW SHOULD BRING IN EVEN MILDER TEMPERATURES THIS WEEKEND...WITH SOME LOCATIONS SEEING AFTERNOON HIGHS APPROACHING 20 DEGREES ABOVE- NORMAL. A MORE SIGNIFICANT STORM SYSTEM WILL TRACK ACROSS THE GREAT LAKES AND INTO NEW ENGLAND MONDAY INTO TUESDAY...DRAGGING A COLD FRONT ACROSS CENTRAL PA. THIS SYSTEM WILL BE ACCOMPANIED BY A PERIOD OF SHOWERY WEATHER...AND FOLLOWED BY A COOL-DOWN BY THE MIDDLE OF NEXT WEEK. && .AVIATION /12Z WEDNESDAY THROUGH SUNDAY/... HIGH PRESSURE ALONG THE ATLC COAST WILL PROVIDE GENERALLY CLEAR SKIES AND LIGHT WINDS THIS EVENING...ALLOWING REDEVELOPMENT OR THICKENING OF LOW FOG/LOW LEVEL CIGS ESPECIALLY AT LOCATIONS THAT REMAINED LOW TODAY. AREA OF MID CLOUDS WILL SPREAD WEST TO EAST OVERNIGHT AHEAD OF WEATHER SYSTEM OVER THE PLAINS. THIS MAY HELP TO DISRUPT LOWER CONDS...AT LEAST TEMPORARILY OVERNIGHT. SLOW IMPROVEMENT IS EXPECTED WEDNESDAY AS SFC WINDS INCREASE AHD OF THE APPROACHING WEATHER SYSTEM. THIS SYSTEM WILL BRING SHOWERS TO THE REGION WED NIGHT. OUTLOOK... TUE NIGHT-WED NIGHT...CHANCE FOR MVFR CIGS. THU-FRI...MVFR POSS NW. SAT...MVFR WITH CHC SHRA. SUN...VFR. && .CTP WATCHES/WARNINGS/ADVISORIES... FREEZING FOG ADVISORY UNTIL 10 AM EST THIS MORNING FOR PAZ012- 017>019-025>028-034-035-041-045-046-049-050. && $$ SYNOPSIS...LAMBERT NEAR TERM...LAMBERT SHORT TERM...LAMBERT LONG TERM...EVANEGO AVIATION...DEVOIR/GARTNER
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
141 PM EST WED DEC 9 2015 .UPDATE... ISSUED AT 141 PM EST WED DEC 9 2015 A FEW RADAR RETURNS HAVE POPPED UP ACROSS THE AREA IN THE PAST FEW HOURS. SO FAR...THESE HAVE NOT PRODUCED MUCH MORE THAN A FEW SPRINKLES AT BEST. THE LATEST HRRR MODEL RUNS CONTINUE TO SHOW A BIT OF AN UPTICK ACROSS OUR SOUTHEAST THROUGH THIS EVENING...SO WILL STICK WITH THE CHANCE POPS FOR NOW. ALSO FRESHENED UP THE SKY COVER AND HOURLY TEMPERATURES AND DEW POINTS TO JIVE BETTER WITH THE CURRENT OBSERVATIONS. UPDATES HAVE BEEN SENT. UPDATE ISSUED AT 1031 AM EST WED DEC 9 2015 MOSTLY CLOUDY SKIES ARE CURRENTLY ON OUR DOORSTEP...AS A SHORT WAVE TROUGH MOVES THROUGH WESTERN KENTUCKY/TENNESSEE. SO FAR...THE RADAR ECHOES HAVE BEEN NON-EXISTENT...BUT THE LATEST SHORT MODEL GUIDANCE CONTINUES TO ADVERTISE AN UPTICK IN ACTIVITY THIS AFTERNOON. AS SUCH...HAVE ONLY DELAYED THE POPS A BIT MORE TOWARDS THE LATEST MODEL TRENDS. ALSO...WENT A BIT HIGHER IN THE SOUTHEAST LATE THIS AFTERNOON...WHERE SLIGHTLY BETTER MOISTURE WILL POOL. THE FORECAST HIGHS LOOK ON TRACK...AND HAVE ONLY FRESHENED UP THE HOURLY TEMPERATURES TO ACCOUNT FOR THE SLOWER DIURNAL RISE IN SOME OF THE MORE SHELTERED VALLEYS THIS MORNING. && .SHORT TERM...(TODAY THROUGH THURSDAY) ISSUED AT 308 AM EST WED DEC 9 2015 A FAST MOVING MOISTURE STARVED UPPER LEVEL WEATHER SYSTEM IS FORECAST TO MOVE ACROSS THE LOWER GREAT LAKES AND OHIO VALLEY REGIONS TODAY...BRINGING LIGHT RAIN SHOWERS TO EASTERN KENTUCKY AS IT DOES SO. BASED ON THE SPEED OF THE SYSTEM AND THE LACK OF A GOOD MOISTURE FEED FOR IT TO INTERACT WITH...PRECIPITATION CHANCES FOR TODAY WERE LEFT FAIRLY LOW. A GENERAL 20 TO 30 PERCENT CHANCE OF RAIN IS ON TAP FOR TODAY ACROSS THE AREA. CLOUD COVER WILL BE ON THE INCREASE EARLY THIS MORNING AS THE SYSTEM APPROACHES...WITH THE FIRST RAIN SHOWERS EXPECTED TO ENTER THE WESTERN COUNTIES OF OUR AREA BETWEEN 17 AND 18Z TODAY. THE LAST OF THE RAIN SHOULD BE EXITING EASTERN KENTUCKY BETWEEN 7 AND 8Z TONIGHT. ONLY VERY LIGHT RAINFALL ACCUMULATIONS ARE EXPECTED. TEMPERATURES BOTH TODAY AND TOMORROW WILL BE RUNNING ABOVE NORMAL...WITH HIGHS TODAY AND THURSDAY TOPPING OUT IN THE MID AND UPPER 50S RESPECTIVELY. OVERNIGHT LOWS SHOULD ONLY FALL INTO THE MID 40S DUE TO EXTENSIVE CLOUD COVER AND LIGHT SOUTHERLY FLOW. .LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY) ISSUED AT 430 AM EST WED DEC 9 2015 THE PERIOD IS EXPECTED TO BEGIN WITH RIDGING EXTENDING FROM THE PACIFIC EAST ACROSS MEXICO AND INTO THE WESTERN GULF OF MEXICO. A TROUGH IS EXPECTED TO BE PUSHING ONSHORE OF THE WESTERN CONUS WITH A TROUGH MOVING INTO THE WESTERN GREAT LAKES. AT THE SFC..A LOW PRESSURE SYSTEM ASSOCIATED WITH THE TROUGH MOVING INTO THE GREAT LAKES SHOULD TRACK INTO ONTARIO AND SEND A COLD FRONT TOWARD THE OHIO VALLEY WHERE IT SHOULD STALL BEFORE LIFTING NORTH TO START THE WEEKEND. THE PATTERN IS EXPECTED TO AMPLIFY EARLY IN THE PERIOD WITH HEIGHTS RISING ACROSS THE APPALACHIAN REGION ON FRIDAY AS RIDGING BUILDS FROM THE GULF OF MEXICO INTO THE SOUTHEASTERN CONUS. AT THE SAME TIME A TROUGH SHOULD DIG SOUTH INTO THE DESERT SOUTHWEST. AT LEAD SHORTWAVE SHOULD LEAD TO A SFC LOW TRACKING NORTHWEST OF THE AREA FRIDAY NIGHT...WITH THE BOUNDARY THAT DROPS TOWARD THE OH RIVER EARLY IN THE PERIOD LIFTING INTO THE GREAT LAKES AS A WARM FRONT. THIS WILL LEAVE THE REGION IN THE WARM SECTOR TO START THE WEEKEND...AND LIGHT SHOWERS OR SPRINKLES CANNOT BE RULED OUT AS THE BOUNDARY DROP INTO THE OHIO VALLEY ON FRIDAY AND THEN LIFTS NORTH THROUGH EARLY ON SATURDAY. OTHERWISE...WITH THE RIDGE BUILDING TOWARD BERMUDA BEFORE SHIFTING OFF THE EASTERN SEABOARD AND THE CURRENT MODEL CONSENSUS OF A DEEPER/SLOWER TROUGH...AT LEAST FOR NOW...MUCH OF SATURDAY INTO MIDDAY SUNDAY SHOULD END UP DRY ALTHOUGH CLOUDS WILL PASS BY FROM TIME TO TIME. THE CURRENT MODEL CONSENSUS IS FOR THE TROUGH TO APPROACH THE MS VALLEY LATE ON SUNDAY AND THEN MOVE INTO THE EASTERN CONUS ON SUN NIGHT...WITH THE SFC COLD FRONT PRECEDING THIS ENTERING THE LOWER OH VALLEY ON SUN AFTERNOON AND EVENING. THERE STILL REMAINS RUN TO RUN AND MODEL TO MODEL VARIABILITY IN THE DEPTH OF THE TROUGH LEADING TO SPREAD IN THE TRACK OF THE SFC LOW INTO THE GREAT LAKES REGION. RECENT MODEL RUNS POINT TOWARD THE TROUGH AXIS NOT MOVING EAST OF THE AREA UNTIL THE DAY ON MONDAY WITH THE COLD FRONT MOVING ACROSS SOUTH CENTRAL AND EASTERN KY ON SUN NIGHT INTO EARLY ON MONDAY MORNING. WARM ADVECTION AHEAD OF AN APPROACHING COLD FRONT AND A DOWNSLOPE COMPONENT OFF THE HIGHER TERRAIN OF NE TN AND SW VA MAY LEAD TO NEAR RECORD OR RECORD HIGHS AT LOZ AND JKL FOR SAT AND SUN. MORE CLOUD COVER THAN ANTICIPATED COULD KEEP TEMPERATURES FROM ACHIEVING THESE VALUES. OVERALL...THE SOUTHEASTERN PART OF THE AREA NEAR THE VA BORDER AND ACROSS THE BIG SANDY REGION STANDS THE BEST CHANCE TO NEAR OR POSSIBLY EXCEED 70 DEGREES ON ONE OR BOTH DAYS. INSTABILITY PARAMETERS ARE GENERALLY MEAGER WITH THIS SYSTEM...SO THUNDER CHANCES APPEAR TOO LOW TO INCLUDE ATTM. HOWEVER..THE PRESSURE GRADIENT WILL INCREASE AS THE END OF WEEK SYSTEM APPROACHES AND WINDS SHOULD INITIALLY BE RATHER STRONG AND GUSTY ACROSS THE HIGHER TERRAIN BY MIDDAY ON SUN...AND SOME OF THIS HIGHER MOMENTUM COULD MIX DOWN TO LOWER ELEVATIONS DURING THE SUN AFTERNOON TO MON AFTERNOON PERIOD ALTHOUGH WINDS ALOFT APPEAR STRONGEST FROM LATE SUN AFTERNOON INTO SUN NIGHT. THE DOWNSLOPE COMPONENT AND THE POTENTIAL FOR MORE VIGOROUS CONVECTION ALONG THE GULF COAST STATES MAY LEAD TO A DRY DAY ON SUN IN THE FAR SOUTHEAST AND LESS QPF AREA WIDE THAN SOME OF THE EARLIER MODEL RUNS. EVEN SO...A SOAKING RAIN WILL PROBABLY OCCUR WITH THIS SYSTEM...BUT WIDESPREAD 1 INCH OR HIGHER AMOUNTS SEEM LESS PROBABLE AT THIS TIME. THE HIGHEST POPS AREA WIDE SHOULD OCCUR ON SUNDAY NIGHT WHERE LIKELY WAS USED. A RIDGE OF HIGH PRESSURE WILL NOSE INTO THE AREA TO END THE PERIOD WITH DRY WEATHER ANTICIPATED. EVEN BEHIND THIS FRONT...TEMPERATURES SHOULD REMAIN ABOVE NORMAL INTO THE MIDDLE OF NEXT WEEK. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 141 PM EST WED DEC 9 2015 VFR CONDITIONS WILL GIVE WAY TO MVFR CEILINGS FROM WEST TO EAST THROUGH 22Z. A FEW SHOWERS WILL DOT THE AREA THROUGH THIS EVENING AS WELL...BUT THESE WILL BE LIGHT AND LIKELY NOT RESTRICT VISIBILITIES TO LESS THAN VFR. CEILINGS WILL CONTINUE TO LOWER LATER TONIGHT...WITH SOME IFR CONDITIONS EXPECTED JUST BEFORE DAWN. A GRADUAL IMPROVEMENT TO MVFR WILL THEN OCCUR THROUGH THURSDAY MORNING. SOUTH TO SOUTHWEST WINDS WILL AVERAGE BETWEEN 5 AND 10 KTS THROUGH THE PERIOD. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...GEOGERIAN SHORT TERM...AR LONG TERM...JP AVIATION...GEOGERIAN
AREA FORECAST DISCUSSION
NWS RALEIGH NC
320 PM EST WED DEC 9 2015 .SYNOPSIS...AN UPPER LEVEL DISTURBANCE WILL TRACK EASTWARD ACROSS THE REGION TONIGHT. ZONAL FLOW ALOFT ON THURSDAY WILL GRADUALLY TRANSITION TO SOUTHWEST FLOW ALOFT OVER THE WEEKEND AS AN UPPER LEVEL RIDGE BUILDS ALONG OR JUST OFFSHORE THE SOUTHEAST COAST. && .NEAR TERM /TONIGHT/... AS OF 255 PM WEDNESDAY... A PROGRESSIVE SHORTWAVE TROUGH EXTENDING FROM THE GREAT LAKES SOUTH INTO THE TN VALLEY WILL TRACK EAST ACROSS THE CAROLINAS AND MID- ATLANTIC THIS EVENING. LOW-LEVEL FLOW ALONG THE COAST WILL BACK AND STRENGTHEN WITH THE APPROACH OF 40-60M SYNOPTIC H5 FALLS. THE RESULTANT WARM MOIST AIR ADVECTION COUPLED WITH LIFT WITHIN THE RIGHT ENTRANCE REGION OF A 70KT JET MAXIMA WILL SUPPORT A CHANCE OF SHALLOW CONVECTION/SHOWERS BREAKING OUT ACROSS THE SC/NC COASTAL PLAIN THIS AFTERNOON AND EVENING...WITH INCREASINGLY AGITATED CUMULUS FIELD CURRENTLY OVER COASTAL CAROLINA EVIDENCE OF THE PRE- CONVECTIVE INITIATION CURRENTLY UNDERWAY. WILL MAINTAIN SMALL CHANCE POPS ALONG AND EAST OF THE I-95 CORRIDOR...TAPERING OFF TO SLIGHT CHANCE EXTENDING WEST TO THE HWY 1 CORRIDOR AND EXITING THE EASTERN CORRIDOR ~06Z. A GRADUAL WEST-EAST CLEARING TREND AFTER MIDNIGHT MAY ALLOW DENSE FOG TO DEVELOP ONCE AGAIN THU MORNING. HRRR AND RAP MODEL FIELDS ARE NOT AS APPARENT AS LAST NIGHT AND AS SUCH CONFIDENCE IS TOO LOW AT THIS TIME TO ISSUE A DENSE FOG ADVISORY. LOWS OVERNIGHT IN THE UPPER 30S TO LOWER 40S NORTHWEST PIEDMONT TO MID/UPPER 40S EAST. && .SHORT TERM /THURSDAY AND THURSDAY NIGHT/... AS OF 250 PM WEDNESDAY... IN THE WAKE OF THE SHORTWAVE TROUGH PASSAGE TONIGHT...ZONAL FLOW ALOFT WILL BECOME ESTABLISHED ON THURSDAY. SHORTWAVE ENERGY EMBEDDED IN THE ZONAL FLOW ALOFT MAY SUPPORT PERIODS OF BROKEN HIGH CLOUDS. OTHERWISE...AFTER MORNING FOG DISPERSES EXPECT PARTLY TO MOSTLY SUNNY SKIES. HIGHS IN THE LOWER TO MID 60S. LOWS THU NIGHT LOWER/MIDDLE 40S. && .LONG TERM /FRIDAY THROUGH WEDNESDAY/... AS OF 315 PM THURSDAY... FRIDAY THROUGH SUNDAY: MID/UPPER LEVEL FLOW PATTERN WILL BECOME MORE AMPLIFIED AGAIN DURING THIS PERIOD (THROUGH THE WEEKEND)... WITH TROUGHING ACROSS THE WESTERN U.S... WITH A BUILDING RIDGE ACROSS THE EAST COAST. MEANWHILE... SURFACE HIGH PRESSURE WILL LINGER ALONG/OFF THE SOUTHEAST U.S. COAST. THIS WILL RESULT IN A WARM AND DRY PERIOD FOR CENTRAL NC... WITH WELL ABOVE NORMAL TEMPS. HIGH TEMPS ARE EXPECTED TO RANGE FROM THE UPPER 60 TO LOWER 70S FRIDAY TO THE LOWER TO MID 70S DURING THE WEEKEND. LOWS WILL FOLLOW A SIMILAR TREND... WELL ABOVE NORMAL... GENERALLY RANGING FROM THE MID 40S TO THE LOWER 50S. SUNDAY NIGHT THROUGH WEDNESDAY: THE NEXT SYSTEM WILL APPROACH FROM THE WEST ON SUNDAY NIGHT. HOWEVER... THE MAIN ENERGY WITH THE SYSTEM IS EXPECTED TO PASS WELL TO THE NORTH... WITH A TRAILING COLD FRONT MOVING ACROSS THE AREA ON MONDAY/MONDAY EVENING WITH A CHANCE OF SHOWERS GENERALLY ALONG AND AHEAD OF THE FRONT. DRY AND COOLER WEATHER IS EXPECTED FOR TUESDAY AND WEDNESDAY BEHIND THE FRONT... THOUGH HIGH TEMPS ARE STILL EXPECTED TO REMAIN ABOVE NORMAL... GENERALLY IN THE 60S. HIGHS ON MONDAY WILL BE WARM AGAIN... GENERALLY RANGING FROM THE MID 60S TO THE LOWER TO MID 70S. && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... AS OF 120 PM WEDNESDAY... 24-HR TAF PERIOD: WAA IN ADVANCE OF AN UPPER LEVEL TROUGH THAT WILL MOVE EAST THROUGH THE AREA THIS EVENING WILL SUPPORT SCATTERED LIGHT RAIN SHOWERS ACROSS OVER THE SANDHILLS AND COASTAL PLAIN BETWEEN 21Z TO 06Z. A BRIEF PERIOD OF MVFR CEILINGS IS POSSIBLE AT KFAY AND KRWI AS THE SHOWERS MOVE THROUGH THE AREA. GRADUAL CLEARING FROM WEST-EAST AFTER MIDNIGHT MAY ALLOW DENSE FOG TO DEVELOP ACROSS PORTIONS OF CENTRAL NC ONCE AGAIN BETWEEN 06 TO 14Z THURSDAY. ANY FOG THAT DEVELOPS SHOULD LIFT TO VFR BY 15Z. LOOKING AHEAD: ASIDE FROM A POTENTIAL FOR SEVERAL HOURS OF SUB-VFR FOG AND/OR STRATUS... EXPECT VFR CONDITIONS TO PREVAIL THROUGH THE WEEKEND. A COLD FRONT WILL MOVE THROUGH THE AREA EARLY MONDAY. SHOWERS AND A BRIEF PERIOD PERIOD OF SUB-VFR CONDITIONS MAY ACCOMPANY THE FRONT. && .CLIMATE... RECORD HIGH TEMPERATURES FOR SAT-SUN DECEMBER 12-13: RALEIGH AREA... 12/12... 79 (2007) AND 12/13... 77 (1927). GREENSBORO AREA... 12/12... 77 (2007) AND 12/13... 76 (1927). FAYETTEVILLE AREA... 12/12... 81 (1931) AND 12/13... 81 (1927). && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...VINCENT NEAR TERM...CBL SHORT TERM...CBL LONG TERM...77 AVIATION...CBL CLIMATE...BADGETT
AREA FORECAST DISCUSSION
NWS RALEIGH NC
255 PM EST WED DEC 9 2015 .SYNOPSIS...AN UPPER LEVEL DISTURBANCE WILL TRACK EASTWARD ACROSS THE REGION TONIGHT. ZONAL FLOW ALOFT ON THURSDAY WILL GRADUALLY TRANSITION TO SOUTHWEST FLOW ALOFT OVER THE WEEKEND AS AN UPPER LEVEL RIDGE BUILDS ALONG OR JUST OFFSHORE THE SOUTHEAST COAST. && .NEAR TERM /TONIGHT/... AS OF 255 PM WEDNESDAY... A PROGRESSIVE SHORTWAVE TROUGH EXTENDING FROM THE GREAT LAKES SOUTH INTO THE TN VALLEY WILL TRACK EAST ACROSS THE CAROLINAS AND MID- ATLANTIC THIS EVENING. LOW-LEVEL FLOW ALONG THE COAST WILL BACK AND STRENGTHEN WITH THE APPROACH OF 40-60M SYNOPTIC H5 FALLS. THE RESULTANT WARM MOIST AIR ADVECTION COUPLED WITH LIFT WITHIN THE RIGHT ENTRANCE REGION OF A 70KT JET MAXIMA WILL SUPPORT A CHANCE OF SHALLOW CONVECTION/SHOWERS BREAKING OUT ACROSS THE SC/NC COASTAL PLAIN THIS AFTERNOON AND EVENING...WITH INCREASINGLY AGITATED CUMULUS FIELD CURRENTLY OVER COASTAL CAROLINA EVIDENCE OF THE PRE- CONVECTIVE INITIATION CURRENTLY UNDERWAY. WILL MAINTAIN SMALL CHANCE POPS ALONG AND EAST OF THE I-95 CORRIDOR...TAPERING OFF TO SLIGHT CHANCE EXTENDING WEST TO THE HWY 1 CORRIDOR AND EXITING THE EASTERN CORRIDOR ~06Z. A GRADUAL WEST-EAST CLEARING TREND AFTER MIDNIGHT MAY ALLOW DENSE FOG TO DEVELOP ONCE AGAIN THU MORNING. HRRR AND RAP MODEL FIELDS ARE NOT AS APPARENT AS LAST NIGHT AND AS SUCH CONFIDENCE IS TOO LOW AT THIS TIME TO ISSUE A DENSE FOG ADVISORY. LOWS OVERNIGHT IN THE UPPER 30S TO LOWER 40S NORTHWEST PIEDMONT TO MID/UPPER 40S EAST. && .SHORT TERM /THURSDAY AND THURSDAY NIGHT/... AS OF 250 PM WEDNESDAY... IN THE WAKE OF THE SHORTWAVE TROUGH PASSAGE TONIGHT...ZONAL FLOW ALOFT WILL BECOME ESTABLISHED ON THURSDAY. SHORTWAVE ENERGY EMBEDDED IN THE ZONAL FLOW ALOFT MAY SUPPORT PERIODS OF BROKEN HIGH CLOUDS. OTHERWISE...AFTER MORNING FOG DISPERSES EXPECT PARTLY TO MOSTLY SUNNY SKIES. HIGHS IN THE LOWER TO MID 60S. LOWS THU NIGHT LOWER/MIDDLE 40S. && .LONG TERM /FRIDAY THROUGH TUESDAY/... AS OF 245 AM WEDNESDAY... A WARM DRY PERIOD IS EXPECTED WITH HIGH CONFIDENCE FRIDAY THROUGH THE WEEKEND. LOWS WILL WARM FROM THE 40S FRIDAY INTO THE LOWER TO MID 50S SUNDAY AND MONDAY. HIGHS WILL REACH THE LOW TO MID 70S IN MOST AREAS ESPECIALLY OVER THE WEEKEND. THERE IS ONLY A SLIGHT CHANCE THAT DAILY RECORD HIGHS MAY BE CHALLENGED BOTH DAYS. SEE THE CLIMATE SECTION BELOW. THE NEXT CHANCE OF SHOWERS SHOULD BE SUNDAY NIGHT INTO MONDAY WITH THE APPROACH OF OUR NEXT FRONT. THE MAIN STORM TRACK WILL BE WELL NORTHWEST OF THE REGION... WITH JUST THE TRAILING COLD FRONT CROSSING OUR AREA ON SUNDAY NIGHT/MONDAY (OR MONDAY NIGHT/TUESDAY). BEHIND THE FRONT...COOLER AND DRIER CONDITIONS ARE EXPECTED ON TUESDAY. TEMPS WILL BE TEMPERED SOME (COMPARED TO PREVIOUS DAYS) ON MONDAY GIVEN THE CLOUDS AND RAIN...WITH LOW TO UPPER 60S EXPECTED. THEN UPPER 50S TO LOWER 60S ARE EXPECTED ON TUESDAY BEHIND THE FRONT. OVERNIGHT LOWS WILL RETURN TO THE UPPER 30S AND 40S BY EARLY NEXT WEEK. && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... AS OF 120 PM WEDNESDAY... 24-HR TAF PERIOD: WAA IN ADVANCE OF AN UPPER LEVEL TROUGH THAT WILL MOVE EAST THROUGH THE AREA THIS EVENING WILL SUPPORT SCATTERED LIGHT RAIN SHOWERS ACROSS OVER THE SANDHILLS AND COASTAL PLAIN BETWEEN 21Z TO 06Z. A BRIEF PERIOD OF MVFR CEILINGS IS POSSIBLE AT KFAY AND KRWI AS THE SHOWERS MOVE THROUGH THE AREA. GRADUAL CLEARING FROM WEST-EAST AFTER MIDNIGHT MAY ALLOW DENSE FOG TO DEVELOP ACROSS PORTIONS OF CENTRAL NC ONCE AGAIN BETWEEN 06 TO 14Z THURSDAY. ANY FOG THAT DEVELOPS SHOULD LIFT TO VFR BY 15Z. LOOKING AHEAD: ASIDE FROM A POTENTIAL FOR SEVERAL HOURS OF SUB-VFR FOG AND/OR STRATUS... EXPECT VFR CONDITIONS TO PREVAIL THROUGH THE WEEKEND. A COLD FRONT WILL MOVE THROUGH THE AREA EARLY MONDAY. SHOWERS AND A BRIEF PERIOD PERIOD OF SUB-VFR CONDITIONS MAY ACCOMPANY THE FRONT. && .CLIMATE... RECORD HIGH TEMPERATURES FOR SAT-SUN DECEMBER 12-13: RALEIGH AREA... 12/12... 79 (2007) AND 12/13... 77 (1927). GREENSBORO AREA... 12/12... 77 (2007) AND 12/13... 76 (1927). FAYETTEVILLE AREA... 12/12... 81 (1931) AND 12/13... 81 (1927). && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...VINCENT NEAR TERM...CBL SHORT TERM...CBL LONG TERM...BADGETT AVIATION...CBL CLIMATE...BADGETT
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
550 PM EST WED DEC 9 2015 .SYNOPSIS... A WEAKENING COLD FRONT WILL TRACK THROUGH THE REGION LATER TONIGHT AND EARLY THURSDAY...FOLLOWED AN ANOMALOUSLY STRONG UPPER RIDGE THAT WILL BRING WARMER THAN NORMAL CONDITIONS FROM THE END OF THE WEEK INTO NEXT WEEK. && .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/... NE WIND HAS RESULTED IN MORE DENSE FOG AT AOO. MOST AREAS SE TO NW WINDS NOW. OTHER SITES NOT BAD...WILL CONTINUE TO MONITOR THE NEED FOR A DENSE FOG OR FREEZING FOG ADVISORY. STILL A STRONG INVERSION IN PLACE...BUT BINOVC ALLOWED TEMPERATURES TO CLIMB ABOVE HIGHS YESTERDAY BY ABOUT 5 TO 10 DEGREES. ALSO WINDS PICKING UP FROM THE SOUTH...VAD WINDS ABOUT 20 KNOTS AT 3000 FEET. LINE OF VERY LIGHT SHOWERS TO THE WEST. WILL HAVE TO MONITOR THE TEMPERATURES. STILL 32 DEGREES AT THE RDA. EARLIER DISCUSSION BELOW. SATELLITE SHOWS THE LOW CLOUDS MELTING AWAY VERY...VERY SLOWLY AT THE EDGES. OTHERWISE BANDS OF FRONTAL CLOUDS ASSOCIATED WITH A WEAKENING COLD FRONT ARE ENTERING EASTERN OHIO AND WILL OVERSPREAD THE REGION TONIGHT. HAVE BEEN USING THE HRRR TRYING TO GET A HANDLE ON THE VERY NEAR TERM CLOUDS AND TEMPERATURE TRENDS. IT HAS BEEN TOO FAST ERODING THE LOW CLOUDS BUT 2M TEMPS AND PBL PROGS SUGGEST KEEPING THE IMPROVEMENT SLOW FOR CENTRAL AREAS. NEAR TERM MODELS ARE IN GOOD AGREEMENT IN SHEARING THE PARENT UPPER TROUGH OUT AND TRACKING IT NORTH OF THE REGION. RAIN SHOWERS WILL APPROACH MY FAR NWRN ZONES BY NIGHTFALL BEFORE TRACKING ACROSS THE FCST AREA OVERNIGHT AND WEAKENING. THE BEST CHANCE FOR RAIN WILL BE OVER THE NORTHWEST AND DURING THE HOURS BEFORE MIDNIGHT...WITH POPS DWINDLING OVER CENTRAL AND EASTERN AREAS FOR THE SECOND HALF OF THE OVERNIGHT. OVERNIGHT LOWS IN THE MID TO UPPER 30S WILL ACTUALLY AVERAGE SOME 10-15 DEG WARMER THAN NORMAL IN MOST SPOTS. && .SHORT TERM /6 AM THURSDAY MORNING THROUGH 6 PM THURSDAY/... ANOTHER WEAKENING FRONT IS EXPECTED TO SHEAR OUT TO OUR NW...WITH HIGH PRESSURE ESTABLISHING ITSELF OFF TO OUR SOUTHWEST. THE NET EFFECT WILL BE FOR A SOUTHWEST FLOW TO SET UP WHICH SHOULD HELP SCOUR OUT THE PERSISTENT LOW CLOUDS AND FOG THAT HAVE PLAGUED THE REGION FOR THE LAST SEVERAL DAYS. WITH AN INCREASE IN SUNSHINE AND A MILDER SOUTHWEST FLOW EXPECTED TO DEVELOP...HIGHS TUESDAY WILL AVERAGE IN THE LOW TO MID 50S...STILL SOME 10-15 DEG WARMER THAN NORMAL. && .LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/... ABOVE NORMAL TO NEAR-RECORD WARMTH WILL BE THE MAIN STORY THIS PERIOD...WITH DAYTIME HIGHS FCST +20 TO +30 DEGREES ABOVE CLIMO BY LATE IN THE WEEKEND. POSSIBLE LOW CLOUDS AND FOG MAY COMPLICATE THINGS AT FIRST AND WILL ASSESS THIS RISK IN THE SHORT RANGE. THE GREATEST RISK FOR RAIN WILL LIKELY BE ON MONDAY WITH ABOVE AVERAGE CONFIDENCE IN THE PCPN PATTERN THIS FAR OUT GIVEN VERY GOOD MODEL AND ENSEMBLE AGREEMENT. TEMPERATURES ARE FCST TO STAY RELATIVELY MILD FOR DECEMBER THROUGH MUCH OF NEXT WEEK WITH A COOL DOWN TO "NEAR NORMAL" POSSIBLE AROUND THE 18-19TH. && .AVIATION /00Z THURSDAY THROUGH MONDAY/... WITH THE EXCEPTION OF BFD/JST...LOW CLOUDS CONTINUE TO PLAGUE CENTRAL AND EASTERN PA TERMINALS. THERE ARE SIGNS HOWEVER THAT THE LOW CLOUDS ARE BEGINNING TO ERODE AROUND THE EDGES WITH ALTOONA RECENTLY IMPROVING TO 2 MILES IN FOG AND EVEN A FEW RAYS OF SUN BEING SEEN OUT THE WINDOW HERE AT TIMES. I`M NOT TOO OPTIMISTIC FOR WIDESPREAD IMPROVEMENT HOWEVER AS WE HAVE VERY LOW SUN ANGLES AND STILL VERY LIGHT WINDS. HRRR STILL SHOWS THE LOW CLOUDS OVER CENTRAL PA FINALLY BEGINNING TO BREAK UP DURING THE AFTERNOON...WITH THE LOW CLOUDS HANGING TOUGH OVER THE LOWER SUSQ VALLEY. WINDS WILL GENERALLY BE LIGHT...WITH SPEEDS OVER THE NW MOUNTAINS INCREASING TO AROUND 8-10KT THIS AFTERNOON AHEAD OF AN APPROACHING WEAK TROUGH. THE WEAK TROUGH WILL MOVE INTO THE REGION TONIGHT AND BRING AN INFLUX OF LOW-LEVEL MOISTURE TO WESTERN AND CENTRAL PA. THIS WILL BRING A RETURN OF CIG RESTRICTIONS TO WESTERN AND CENTRAL SECTIONS ALONG WITH SOME LIGHT RAIN SHOWERS. OVER MY SOUTHEASTERN TERMINALS THE LOW CLOUDS FROM TODAY WILL CONTINUE TO HANG TOUGH WITH EVEN THE POTENTIAL FOR THE FOG TO REDEVELOP UNDER THE PERSISTENT LOW LEVEL INVERSION. THE WEAKENING FRONT/TROUGH WILL SWING THROUGH THE AREA LATE TONIGHT OR EARLY THURSDAY AND FINALLY BRING A DRIER WESTERLY FLOW TO THE LOCAL FLYING AREA. WE SHOULD START THE DAY WITH FAIRLY WIDESPREAD IFR/MVFR CEILINGS AND EVEN SOME FOG OVER EASTERN AREAS...BUT CONDITIONS WILL IMPROVE TO VFR BY LATE MORNING OR EARLY AFTERNOON AS THE WEST-SOUTHWEST FLOW FRESHENS. OUTLOOK... FRI...AREAS OF MORNING FOG. THEN MAINLY VFR. SAT...MVFR WITH CHC SHRA NW HALF. MAINLY VFR SE. SUN...MAINLY VFR. MON...FROPA WITH WIDESPREAD SHOWERS AND MVFR/IFR. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...LA CORTE NEAR TERM...LA CORTE/MARTIN SHORT TERM...LA CORTE LONG TERM...STEINBUGL AVIATION...LA CORTE
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
347 PM EST WED DEC 9 2015 .SYNOPSIS... A WEAKENING COLD FRONT WILL TRACK THROUGH THE REGION LATER TONIGHT AND EARLY THURSDAY...FOLLOWED AN ANOMALOUSLY STRONG UPPER RIDGE THAT WILL BRING WARMER THAN NORMAL CONDITIONS FROM THE END OF THE WEEK INTO NEXT WEEK. && .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/... SATELLITE SHOWS THE LOW CLOUDS MELTING AWAY VERY...VERY SLOWLY AT THE EDGES. OTHERWISE BANDS OF FRONTAL CLOUDS ASSOCIATED WITH A WEAKENING COLD FRONT ARE ENTERING EASTERN OHIO AND WILL OVERSPREAD THE REGION TONIGHT. HAVE BEEN USING THE HRRR TRYING TO GET A HANDLE ON THE VERY NEAR TERM CLOUDS AND TEMPERATURE TRENDS. IT HAS BEEN TOO FAST ERODING THE LOW CLOUDS BUT 2M TEMPS AND PBL PROGS SUGGEST KEEPING THE IMPROVEMENT SLOW FOR CENTRAL AREAS. NEAR TERM MODELS ARE IN GOOD AGREEMENT IN SHEARING THE PARENT UPPER TROUGH OUT AND TRACKING IT NORTH OF THE REGION. RAIN SHOWERS WILL APPROACH MY FAR NWRN ZONES BY NIGHTFALL BEFORE TRACKING ACROSS THE FCST AREA OVERNIGHT AND WEAKENING. THE BEST CHANCE FOR RAIN WILL BE OVER THE NORTHWEST AND DURING THE HOURS BEFORE MIDNIGHT...WITH POPS DWINDLING OVER CENTRAL AND EASTERN AREAS FOR THE SECOND HALF OF THE OVERNIGHT. OVERNIGHT LOWS IN THE MID TO UPPER 30S WILL ACTUALLY AVERAGE SOME 10-15 DEG WARMER THAN NORMAL IN MOST SPOTS. && .SHORT TERM /6 AM THURSDAY MORNING THROUGH 6 PM THURSDAY/... ANOTHER WEAKENING FRONT IS EXPECTED TO SHEAR OUT TO OUR NW...WITH HIGH PRESSURE ESTABLISHING ITSELF OFF TO OUR SOUTHWEST. THE NET EFFECT WILL BE FOR A SOUTHWEST FLOW TO SET UP WHICH SHOULD HELP SCOUR OUT THE PERSISTENT LOW CLOUDS AND FOG THAT HAVE PLAGUED THE REGION FOR THE LAST SEVERAL DAYS. WITH AN INCREASE IN SUNSHINE AND A MILDER SOUTHWEST FLOW EXPECTED TO DEVELOP...HIGHS TUESDAY WILL AVERAGE IN THE LOW TO MID 50S...STILL SOME 10-15 DEG WARMER THAN NORMAL. && .LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/... ABOVE NORMAL TO NEAR-RECORD WARMTH WILL BE THE MAIN STORY THIS PERIOD...WITH DAYTIME HIGHS FCST +20 TO +30 DEGREES ABOVE CLIMO BY LATE IN THE WEEKEND. POSSIBLE LOW CLOUDS AND FOG MAY COMPLICATE THINGS AT FIRST AND WILL ASSESS THIS RISK IN THE SHORT RANGE. THE GREATEST RISK FOR RAIN WILL LIKELY BE ON MONDAY WITH ABOVE AVERAGE CONFIDENCE IN THE PCPN PATTERN THIS FAR OUT GIVEN VERY GOOD MODEL AND ENSEMBLE AGREEMENT. TEMPERATURES ARE FCST TO STAY RELATIVELY MILD FOR DECEMBER THROUGH MUCH OF NEXT WEEK WITH A COOL DOWN TO "NEAR NORMAL" POSSIBLE AROUND THE 18-19TH. && .AVIATION /20Z WEDNESDAY THROUGH MONDAY/... WITH THE EXCEPTION OF BFD/JST...LOW CLOUDS CONTINUE TO PLAGUE CENTRAL AND EASTERN PA TERMINALS. THERE ARE SIGNS HOWEVER THAT THE LOW CLOUDS ARE BEGINNING TO ERODE AROUND THE EDGES WITH ALTOONA RECENTLY IMPROVING TO 2 MILES IN FOG AND EVEN A FEW RAYS OF SUN BEING SEEN OUT THE WINDOW HERE AT TIMES. I`M NOT TOO OPTIMISTIC FOR WIDESPREAD IMPROVEMENT HOWEVER AS WE HAVE VERY LOW SUN ANGLES AND STILL VERY LIGHT WINDS. HRRR STILL SHOWS THE LOW CLOUDS OVER CENTRAL PA FINALLY BEGINNING TO BREAK UP DURING THE AFTERNOON...WITH THE LOW CLOUDS HANGING TOUGH OVER THE LOWER SUSQ VALLEY. WINDS WILL GENERALLY BE LIGHT...WITH SPEEDS OVER THE NW MOUNTAINS INCREASING TO AROUND 8-10KT THIS AFTERNOON AHEAD OF AN APPROACHING WEAK TROUGH. THE WEAK TROUGH WILL MOVE INTO THE REGION TONIGHT AND BRING AN INFLUX OF LOW-LEVEL MOISTURE TO WESTERN AND CENTRAL PA. THIS WILL BRING A RETURN OF CIG RESTRICTIONS TO WESTERN AND CENTRAL SECTIONS ALONG WITH SOME LIGHT RAIN SHOWERS. OVER MY SOUTHEASTERN TERMINALS THE LOW CLOUDS FROM TODAY WILL CONTINUE TO HANG TOUGH WITH EVEN THE POTENTIAL FOR THE FOG TO REDEVELOP UNDER THE PERSISTENT LOW LEVEL INVERSION. THE WEAKENING FRONT/TROUGH WILL SWING THROUGH THE AREA LATE TONIGHT OR EARLY THURSDAY AND FINALLY BRING A DRIER WESTERLY FLOW TO THE LOCAL FLYING AREA. WE SHOULD START THE DAY WITH FAIRLY WIDESPREAD IFR/MVFR CEILINGS AND EVEN SOME FOG OVER EASTERN AREAS...BUT CONDITIONS WILL IMPROVE TO VFR BY LATE MORNING OR EARLY AFTERNOON AS THE WEST-SOUTHWEST FLOW FRESHENS. OUTLOOK... FRI...AREAS OF MORNING FOG. THEN MAINLY VFR. SAT...MVFR WITH CHC SHRA NW HALF. MAINLY VFR SE. SUN...MAINLY VFR. MON...FROPA WITH WIDESPREAD SHOWERS AND MVFR/IFR. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...LA CORTE NEAR TERM...LA CORTE SHORT TERM...LA CORTE LONG TERM...STEINBUGL AVIATION...LA CORTE
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
211 PM EST WED DEC 9 2015 .SYNOPSIS... A WEAKENING COLD FRONT WILL TRACK THROUGH THE REGION LATER TONIGHT AND EARLY THURSDAY...FOLLOWED AN ANOMALOUSLY STRONG UPPER RIDGE THAT WILL BRING WARMER THAN NORMAL CONDITIONS FROM THE END OF THE WEEK INTO NEXT WEEK. && .NEAR TERM /THROUGH TONIGHT/... SATELLITE SHOWS THE LOW CLOUDS MELTING AWAY VERY...VERY SLOWLY AT THE EDGES. OTHERWISE BANDS OF FRONTAL CLOUDS ASSOCIATED WITH A WEAKENING COLD FRONT ARE ENTERING EASTERN OHIO AND WILL OVERSPREAD THE REGION TONIGHT. HAVE BEEN USING THE HRRR TRYING TO GET A HANDLE ON THE VERY NEAR TERM CLOUDS AND TEMPERATURE TRENDS. IT HAS BEEN TOO FAST ERODING THE LOW CLOUDS BUT 2M TEMPS AND PBL PROGS SUGGEST KEEPING THE IMPROVEMENT SLOW FOR CENTRAL AREAS. NEAR TERM MODELS ARE IN GOOD AGREEMENT IN SHEARING THE PARENT UPPER TROUGH OUT AND TRACKING IT NORTH OF THE REGION. RAIN SHOWERS WILL APPROACH MY FAR NWRN ZONES BY NIGHTFALL BEFORE TRACKING ACROSS THE FCST AREA OVERNIGHT AND WEAKENING. THE BEST CHANCE FOR RAIN WILL BE OVER THE NORTHWEST AND DURING THE HOURS BEFORE MIDNIGHT...WITH POPS DWINDLING OVER CENTRAL AND EASTERN AREAS FOR THE SECOND HALF OF THE OVERNIGHT. OVERNIGHT LOWS IN THE MID TO UPPER 30S WILL ACTUALLY AVERAGE SOME 10-15 DEG WARMER THAN NORMAL IN MOST SPOTS. && .SHORT TERM /THURSDAY/... ANOTHER WEAKENING FRONT IS EXPECTED TO SHEAR OUT TO OUR NW...WITH HIGH PRESSURE ESTABLISHING ITSELF OFF TO OUR SOUTHWEST. THE NET EFFECT WILL BE FOR A SOUTHWEST FLOW TO SET UP WHICH SHOULD HELP SCOUR OUT THE PERSISTENT LOW CLOUDS AND FOG THAT HAVE PLAGUED THE REGION FOR THE LAST SEVERAL DAYS. WITH AN INCREASE IN SUNSHINE AND A MILDER SOUTHWEST FLOW EXPECTED TO DEVELOP...HIGHS TUESDAY WILL AVERAGE IN THE LOW TO MID 50S...STILL SOME 10-15 DEG WARMER THAN NORMAL. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... THE MAIN STORY FOR THE LONG TERM CONTINUES TO BE UNSEASONABLY MILD WEATHER...AS WE EXPECT TEMPERATURES ARE EXPECTED TO REMAIN ABOVE- NORMAL RIGHT INTO EARLY NEXT WEEK. AS FOR PRECIPITATION...A WEAKENING TROUGH OF LOW PRESSURE COULD BRING A FEW SHOWERS MAINLY ACROSS THE NORTH AND WEST THU NITE INTO FRI. SATURDAY INTO SUNDAY WILL SEE A SIGNIFICANT UPPER-LEVEL RIDGE BUILD OVER THE EAST COAST. INCREASINGLY SOUTHERLY FLOW SHOULD BRING IN EVEN MILDER TEMPERATURES THIS WEEKEND...WITH SOME LOCATIONS SEEING AFTERNOON HIGHS APPROACHING 20 DEGREES ABOVE- NORMAL. A MORE SIGNIFICANT STORM SYSTEM WILL TRACK ACROSS THE GREAT LAKES AND INTO NEW ENGLAND MONDAY INTO TUESDAY...DRAGGING A COLD FRONT ACROSS CENTRAL PA. THIS SYSTEM WILL BE ACCOMPANIED BY A PERIOD OF SHOWERY WEATHER...AND FOLLOWED BY A COOL-DOWN BY THE MIDDLE OF NEXT WEEK. && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... WITH THE EXCEPTION OF BFD/JST...LOW CLOUDS CONTINUE TO PLAGUE CENTRAL AND EASTERN PA TERMINALS. THERE ARE SIGNS HOWEVER THAT THE LOW CLOUDS ARE BEGINNING TO ERODE AROUND THE EDGES WITH ALTOONA RECENTLY IMPROVING TO 2 MILES IN FOG AND EVEN A FEW RAYS OF SUN BEING SEEN OUT THE WINDOW HERE AT TIMES. I`M NOT TOO OPTIMISTIC FOR WIDESPREAD IMPROVEMENT HOWEVER AS WE HAVE VERY LOW SUN ANGLES AND STILL VERY LIGHT WINDS. HRRR STILL SHOWS THE LOW CLOUDS OVER CENTRAL PA FINALLY BEGINNING TO BREAK UP DURING THE AFTERNOON...WITH THE LOW CLOUDS HANGING TOUGH OVER THE LOWER SUSQ VALLEY. WINDS WILL GENERALLY BE LIGHT...WITH SPEEDS OVER THE NW MOUNTAINS INCREASING TO AROUND 8-10KT THIS AFTERNOON AHEAD OF AN APPROACHING WEAK TROUGH. THE WEAK TROUGH WILL MOVE INTO THE REGION TONIGHT AND BRING AN INFLUX OF LOW-LEVEL MOISTURE TO WESTERN AND CENTRAL PA. THIS WILL BRING A RETURN OF CIG RESTRICTIONS TO WESTERN AND CENTRAL SECTIONS ALONG WITH SOME LIGHT RAIN SHOWERS. OVER MY SOUTHEASTERN TERMINALS THE LOW CLOUDS FROM TODAY WILL CONTINUE TO HANG TOUGH WITH EVEN THE POTENTIAL FOR THE FOG TO REDEVELOP UNDER THE PERSISTENT LOW LEVEL INVERSION. THE WEAKENING FRONT/TROUGH WILL SWING THROUGH THE AREA LATE TONIGHT OR EARLY THURSDAY AND FINALLY BRING A DRIER WESTERLY FLOW TO THE LOCAL FLYING AREA. WE SHOULD START THE DAY WITH FAIRLY WIDESPREAD IFR/MVFR CEILINGS AND EVEN SOME FOG OVER EASTERN AREAS...BUT CONDITIONS WILL IMPROVE TO VFR BY LATE MORNING OR EARLY AFTERNOON AS THE WEST-SOUTHWEST FLOW FRESHENS. OUTLOOK... FRI...AREAS OF MORNING FOG. THEN MAINLY VFR. SAT...MVFR WITH CHC SHRA NW HALF. MAINLY VFR SE. SUN...MAINLY VFR. MON...FROPA WITH WIDESPREAD SHOWERS AND MVFR/IFR. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...LA CORTE NEAR TERM...LA CORTE SHORT TERM...LA CORTE LONG TERM...EVANEGO AVIATION...LA CORTE
AREA FORECAST DISCUSSION
NWS ABERDEEN SD
304 PM CST WED DEC 9 2015 .SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT) ISSUED AT 243 PM CST WED DEC 9 2015 A FAIRLY ACTIVE PATTERN WITH 2 WEAK SYSTEMS DURING THE SHORT TERM. HRRR AND RUC BOTH BRING LIGHT PRECIPITATION INTO THE WESTERN CWA THIS EVENING...WITH PROFILES SUPPORTING A BRIEF PERIOD OF LIGHT RAIN AHEAD OF THIS WAVE ONCE SATURATION IS ACHIEVED...THUS NOT EXPECTING MUCH MORE THAN A HUNDREDTH OR TWO. SURFACE TEMPERATURES WILL LIKELY REMAIN ABOVE FREEZING WITH 925MB TEMPERATURES AROUND +6C AND A PREDOMINANT WEST WIND. THIS WIND WILL ALSO INCREASE TOWARDS MORNING WITH 1/2KM WINDS UPWARDS OF 50KTS...HOWEVER BECAUSE OF THE DEGREE OF COLD ADVECTION...LOW VALUES FOR PRESSURE RISES...AND A 10 TO 12MB PRESSURE GRADIENT ACROSS THE STATE...ANTICIPATE IT WILL BE DIFFICULT TO FULLY REALIZE THESE STRONGER WINDS. WILL LEAVE CURRENT HEADLINE IN PLACE WITH THE REST OF THE CWA POSSIBLY SEEING A FEW GUSTS NEAR ADVISORY CRITERIA DURING PEAK HEATING. THE SECOND WEAK WAVE MOVES IN FOR EARLY FRIDAY. WARM ADVECTION WILL GENERATE ENOUGH LIFT FOR LIGHT PRECIPITATION ALONG AND JUST NORTH OF THE NORTH DAKOTA/SOUTH DAKOTA STATE LINE DURING THE MORNING HOURS...BUT AS THE WAVE CONTINUES TO SHEAR APART...PRECIPITATION INTENSITY WILL LIKELY DROP THROUGH THE MID DAY HOURS. PROFILES ARE MAINLY SUPPORTIVE OF SNOW...WITH GUIDANCE ESTIMATING AROUND AN INCH OR TWO JUST NORTH OF THE CWA. .LONG TERM...(SATURDAY THROUGH WEDNESDAY) ISSUED AT 243 PM CST WED DEC 9 2015 PRECIPITATION CHANCES THIS WEEKEND...AND AGAIN TUESDAY THROUGH WEDNESDAY WILL BE THE FORECAST CHALLENGES. THE PERIOD BEGINS WITH AN UPPER LEVEL TROUGH OF LOW PRESSURE CROSSING THE CENTRAL CONUS. WHILE ALL MODELS SHOW THIS TROUGH...THEY DIFFER ON THE PLACEMENT OF THE PCPN. THE MODEL RUNS FROM LAST NIGHT...WHICH SHOWED DRY CONDITIONS PER THE ECMWF/GEM...HAVE FLIPPED WITH THE 12Z RUN. THE GFS NOW KEEPS THE CWA DRY...WHILE THE ECMWF/GEM BRINGS LIGHT SNOW TO THE EASTERN HALF OF THE CWA SATURDAY THROUGH SUNDAY MORNING. PREFERRED A DRY SOLUTION FOR THE WEEKEND BASED ON THE NAEFS...WHICH SHOWS A MORE SOUTHEASTERLY SOLUTION. AFTER A MOSTLY DRY SUNDAY AND MONDAY...MODELS AGREE FAIRLY WELL WITH A STORM SYSTEM IMPACTING THE REGION TUESDAY THROUGH WEDNESDAY. THIS STORM COULD BRING WIDESPREAD ACCUMULATING SNOWFALL TO THE REGION. OF COURSE IT IS FAR TOO SOON TO TALK SNOWFALL AMOUNTS. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 1132 AM CST WED DEC 9 2015 A WARM FRONT CROSSING THE REGION TODAY WILL SHIFT THE WINDS TO A WESTERLY DIRECTION. THE WESTERLY WINDS WILL CONTINUE THROUGH THE VALID TAF PERIOD. EXPECT THE WINDS TO INCREASE FROM WEST TO EAST ACROSS THE REGION WITH SUSTAINED WINDS OF 20 KNOTS POSSIBLE FOR ALL TERMINALS ON THURSDAY. A SYSTEM CROSSING THE REGION TONIGHT COULD BRING VCSH TO MOST TERMINALS. HOWEVER CONDITIONS SHOULD REMAIN VFR THROUGH THE TAF PERIOD. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...WIND ADVISORY FROM 5 AM TO 2 PM MST THURSDAY FOR SDZ003-015. MN...NONE. && $$ SHORT TERM...CONNELLY LONG TERM...SD AVIATION...SD
AREA FORECAST DISCUSSION
NWS MORRISTOWN TN
300 PM EST WED DEC 9 2015 .SHORT TERM (TONIGHT THROUGH TOMORROW)... CURRENT WATER VAPOR IMAGERY AND RAP UPPER AIR ANALYSIS INDICATES A SHORTWAVE TROUGH ACROSS THE OHIO AND TENNESSEE RIVER VALLEYS. AT THE SURFACE...A COLD FRONT/SURFACE TROUGH IS MOVING INTO MIDDLE TENNESSEE. WIDESPREAD CLOUD COVER EXIST AHEAD OF THIS SURFACE BOUNDARY DUE TO LOW LEVEL ISENTROPIC LIFT. VISIBLE SATELLITE IMAGERY INDICATES RATHER WIDESPREAD CLOUD COVER BACK TO THE WEST AHEAD OF THIS BOUNDARY. LOOKING AT THE RADAR...NOT SEEING MUCH IN THE WAY OF PRECIPITATION SHOWING UP AND HAVE ONLY SEEN AN OB OR 2 REPORT LIGHT RAIN. THEREFORE...WENT AHEAD AND REDUCED POPS SOMEWHAT FOR THIS EVENING/OVERNIGHT WITH POPS AROUND 20-30. HI- RES MODELS INDICATE SCATTERED SHOWERS DEVELOPING AHEAD OF THIS BOUNDARY BUT SEEM TO BE A BIT OVERDONE BASED ON THE CURRENT RADAR TRENDS. REGARDLESS...ANY PRECIPITATION WILL BE LIGHT WITH ONLY THE LOWEST 100-150 MB SATURATED. WIDESPREAD CLOUD COVER AND SOUTHERLY FLOW WILL KEEP LOW TEMPERATURES TONIGHT UP IN THE 40S. NOT A BIG CHANGE IN OVERALL CONDITIONS AS THE TROUGH PASSES TO THE WEST. LOW LEVEL FLOW BEHIND THE TROUGH REMAINS SOUTHERLY TO SOUTHWESTERLY AND COULD SEE CLOUD COVER HOLD IN ACROSS THE EASTERN AREAS NEAR THE MOUNTAINS THROUGHOUT MUCH OF THE DAY TOMORROW. FURTHER TO THE WEST...EXPECT CLOUDS WILL BEGIN TO DECREASE BY THE AFTERNOON. HIGH TEMPERATURES WILL REMAIN ABOVE NORMAL WITH HIGHS IN THE 50S AND 60S. .LONG TERM (THURSDAY NIGHT THROUGH WEDNESDAY)... QUIET CONDITIONS TO BEGIN THE LONG TERM AS MOSTLY ZONAL FLOW IS IN PLACE THROUGH FRIDAY. OVERNIGHT LOWS THURSDAY WILL BE ABOUT 10 DEGREES ABOVE NORMAL. FRIDAY HIGH TEMPS WILL BE AROUND 10 DEGREES ABOVE NORMAL AND LOWS AROUND 15 ABOVE NORMAL. 500MB HEIGHTS RAPIDLY INCREASE ACROSS THE REGION ON SATURDAY AND SUNDAY IN ADVANCE OF A DEEP TROUGH MOVING OUT OF THE PACIFIC NW AND INTO THE PLAINS. MODELS STILL TRENDING TOWARD A SLOWER SYSTEM SO IT LOOKS LIKE CONFIDENCE ON TIMING IS INCREASING. HIGH TEMPS FOR BOTH SATURDAY AND SUNDAY WILL BE IN THE MID TO UPPER 60S WITH THE EXTREME SOUTHERN VALLEY APPROACHING 70. THESE TEMPERATURES WILL BE AROUND 15 DEGREES ABOVE NORMAL. LOWS ON SATURDAY AND SUNDAY NIGHT WILL BE 15 TO 20 DEGREES WARMER THAN NORMAL. IN FACT...OVERNIGHT LOWS ON FRIDAY...SATURDAY AND SUNDAY WILL BE NEAR WHAT OUR NORMAL HIGHS SHOULD BE FOR THIS TIME OF YEAR. BOTH THE 12Z ECMWF AND GFS SHOW THE DEEP TROUGH MOVING INTO WESTERN TN LATE SUNDAY NIGHT AND EARLY MONDAY MORNING. THIS SYSTEM HAS QUITE A BIT OF ENERGY WITH IT BUT WILL BE A FAST MOVER. AMPLE MOISTURE...LIFT...AND GOOD JET STREAM DYNAMICS WILL GIVE US A CHANCE TO SEE MODERATE TO LOCALLY HEAVY RAINS FOR THE LATE SUNDAY NIGHT THROUGH MONDAY MORNING TIME PERIOD. PREVIOUS FORECAST INCLUDED SLIGHT CHANCE OF THUNDER BUT CURRENT SOUNDINGS SHOW VERY LITTLE TO NO CAPE AS THIS SYSTEM MOVES THROUGH SO OPTED TO REMOVE THUNDER FROM FORECAST. HALF AN INCH TO THREE QUARTERS OF AN INCH OF RAIN LOOKS POSSIBLE WITH THIS SYSTEM. TROUGH AND ASSOCIATED LOW RAPIDLY MOVE OFF TO THE NE ON MONDAY WITH CLEARING SKIES BY MID TO LATE AFTERNOON. RIDGING QUICKLY BUILDS BACK IN ON TUESDAY WITH TEMPERATURES IN THE UPPER 50S TO NEAR 60. TUESDAY NIGHT INTO WEDNESDAY OUR NEXT SYSTEM APPROACHES. THE CENTER OF THE LOW WILL BE WELL TO OUR NORTH UP INTO THE GREAT LAKES...BUT ITS ASSOCIATED TRAILING COLD FRONT WILL BE APPROACHING OUR AREA. TIMING WITH THIS SYSTEM WILL LIKELY CHANGE BUT FOR NOW HAVE SLIGHT CHANCE SHOWERS TUESDAY NIGHT WITH LOW END CHANCE ON WEDNESDAY. && .PRELIMINARY POINT TEMPS/POPS... CHATTANOOGA AIRPORT, TN 45 64 49 66 / 10 0 0 10 KNOXVILLE MCGHEE TYSON AIRPORT, TN 46 60 47 64 / 20 0 0 10 OAK RIDGE, TN 45 61 47 64 / 20 0 10 10 TRI CITIES AIRPORT, TN 43 59 39 63 / 20 10 0 10 && .MRX WATCHES/WARNINGS/ADVISORIES... NC...NONE. TN...NONE. VA...NONE. && $$ MA/SR