Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 11/15/16


Area Forecast Discussion
National Weather Service Albany NY
938 PM EST Mon Nov 14 2016 .SYNOPSIS... Clouds will continue to thicken and lower, as a low pressure system moves northeast from Mid Atlantic Coast towards eastern New York and western New England overnight. This system will bring light rain into the region during the late morning through the afternoon. A weak disturbance will move across the region on Wednesday with isolated showers north and west of the Capital District. By Thursday, high pressure will build into the region bringing seasonable temperatures and dry weather. && .NEAR TERM /THROUGH TUESDAY/... As of 938 PM EST...The latest IR satellite picture with RAP data overlayed shows widespread mid and high clouds streaming north/northeast into eastern NY and western New England ahead of a warm front and low pressure system moving northeast from the near the NC/VA border. The atmosphere is super dry in the low levels which is evident in the 00Z KALY RAOB with saturation near 500 hPa or 20 kft AGL. Clouds will continue to thicken and lower and the large T/TD sfc spreads should keep the pcpn from reaching the ground until towards 5-7 am across the extreme southeast portion of the fcst area /southern Dutchess and southern Litchfield Counties/. This is similar to the latest 18Z and 00Z NAM trends and the HRRR. The trends for the pops/wx were slowed down in the grids. The temps really fell off quickly north and east of the Capital Region with the partly clouds skies and calm winds. However...the rate of fall has lessened with the high clouds. Temps were adjusted down a tad over southern VT and the northern Berkshires where temps fell to 32-35F quickly. Expect temps to steady or slowly rise overnight with lows in the 30s with a few upper 20s over the southern Greens/southern Adirondacks. && .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY NIGHT/... Tonight...Clouds will be on the increase as an area of low pressure starts to track up the coast. Areas to the south may see light rain move into the region overnight. With cloudy skies, Low temps will not be as cold as we saw Monday AM. Tuesday...The area of low pressure will continue to move up the east coast. With the low passing by to our south and east, Tuesday will be a cloudy and rainy day. Best area of heaviest qpf will be areas to the south and areas east of the Hudson Valley. QPF values will generally be a quarter to half an inch, with the higher of the amounts across areas east of the Hudson valley. Areas across Mohawk Vally and the Northwestern Adirondacks, may see around a tenth of an inch or less based on current model trends. With clouds and rain, high temperatures will be in the 40s. By Tuesday night, the low will continue to move up the New England coast. Rain will slowly taper off from southwest to northeast. There will still be some low level moisture/wrap around moisture with the low pressure departing. Depending on how long the system takes to clear out...Temps Tuesday night might not drop too much and stay in the mid to upper 30s. Wednesday...Will be between systems as the low departs and an upper level trough approaches the region. Overall Wednesday should be dry with the exception of a few showers possible across the higher terrain with a weak piece of upper level energy. Highs will be in the upper 40s across the Adirondacks to the lower 50s across the valley locations. Thursday...High pressure will build across the southeastern portion of the US. With a southwesterly flow, temperatures will rise above normal. && .LONG TERM /FRIDAY THROUGH MONDAY/... The long term portion of the forecast will start with ridging across the east and a trough with a massive low pressure system across the central portion of the US. High pressure will continue to build into the east on Friday. This will again allow for above normal temperatures and dry conditions. Saturday...a strong area of low pressure at the surface and 500 will be across the great lakes region and start to approach the Northeast late in the day. Overall Saturday will be dry and mild before the frontal passage. Sunday...Colder air will be in place as the low pressure system tracks eastward and a h500 trough digs into the region. The trough will become negatively tilted with time. Short waves of energy will bring showers into the region on Sunday. Temperatures on Sunday will be at normal or a few degrees below normal. Monday...The trough will continue to be over the region with a upper level low. With upper level waves and energy...will keep a chance of showers and normal to slightly below normal temperatures. Key thing to watch with the system on Sunday and Monday is the location of the low and timing. Being seven days out a lot could change. If the timing does hold areas could see some snow Monday night into Tuesday AM. Overall, will have to watch this with time and as confidence gets more solid. && .AVIATION /03Z TUESDAY THROUGH SATURDAY/... A low pressure system will approach from the Mid Atlantic Coast tonight and bring some rainfall into the TAF sites tomorrow morning into the afternoon. VFR conditions are expected for KGFL/KALB/KPOU/KPSF prior to 10Z with cigs lowering ahead of the low pressure system. Expect the clouds to continue to thicken and lower with the increasing warm advection to heights of 4-6 kft AGL btwn 08Z-12Z. Some light rain will start to move into the KPOU area btwn 12Z-14Z and spreading northward to KALB-KPOU...and then KGFL by the 19Z. CIGS/VSBYS will lower to MVFR levels initially...and then to IFR levels in the rainshield especially for KALB-KPSF south and east btwn 14Z-18Z. KGFL may only have low MVFR flight conditions especially in the early to mid afternoon depending on track of the storm. The winds will be light to calm overnight...and then increase from the north to northeast at 4-7 kts late tomorrow morning into the afternoon. Outlook... Tuesday Night: Moderate Operational Impact. Chance of SHRA. Wednesday to Friday night: No Operational Impact. NO SIG WX. Saturday: Slight Chance of SHRA. && .FIRE WEATHER... RH values will recover tonight with increasing amounts of moisture in the atmosphere. A low pressure system will approach the northeast on Tuesday. This will bring rain showers to the region on Tuesday. Rainfall amounts will generally be a quarter to half an inch...with lesser amounts across areas north and west of the Hudson Valley. && .HYDROLOGY... A low pressure system will move up the Atlantic coast tonight and be just east of the area on Tuesday. This will bring rain to the region on Tuesday. Overall QPF amounts should be light enough to not cause any problems. QPF totals will generally be a quarter to half an inch...with lesser amounts across areas north and west of the Hudson Valley. After that, high pressure will build into the region for the end of the week. Our next chance of QPF would be on Sunday as a strong storm system approaches the region. For details on specific area rivers and lakes, including observed and forecast river stages and lake elevations, please visit the Advanced Hydrologic Prediction Service /AHPS/ graphs on our website. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. MA...None. VT...None. && $$ SYNOPSIS...VTK/Wasula NEAR TERM...Wasula SHORT TERM...VTK LONG TERM...VTK AVIATION...Wasula FIRE WEATHER...VTK HYDROLOGY...VTK
Area Forecast Discussion...UPDATED
National Weather Service Columbia SC
1029 PM EST Mon Nov 14 2016 .SYNOPSIS... Dry high pressure will extend into the area from the west through Friday, with above normal temps. A dry cold front will come through Saturday, reinforcing dry conditions with cooler temps for the weekend. && .NEAR TERM /UNTIL 7 AM TUESDAY MORNING/... Strong radiational cooling combined with enhanced low level moisture and near zero dewpoint depressions beneath dry mid levels has resulted in some patchy dense fog across the Pee Dee and parts of the far eastern Midlands. Smoke particulates from the wild fires that moved over the region also likely a contributing factor to fog development. Issued a special weather statement for patchy dense fog to handle for the time being but it is anticipated that a dense fog advisory may be needed later tonight but confidence is low because stratus clouds are also developing which could prevent the dense fog from maintaining or forming. Elsewhere around the forecast area, high concentrations of smoke from the wildfires in the mountains settled over the Midlands and CSRA this evening with visibilities in the 3-6 mile range. Model forecast soundings show a strong inversion setting up overnight and smoke model forecasts show concentrations of smoke increasing through the predawn hours so will continue the mention of areas of smoke in the weather grids. Temperatures overnight will fall into the upper 30s to lower 40s. && .SHORT TERM /7 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/... Upper level trough over the Mid Atlantic region and Northeast States...resulting northwest flow aloft across the Carolinas. Surface ridge over the lower Mississippi valley and Gulf Coast States will build slowly east. Dry air mass over the area...although shallow low-level moisture remains through early morning leading to some fog. In addition to morning fog...HRRR smoke model indicates smoke from Upstate/NC fires will spread into the Midlands during the day. Downsloping winds should result in mild afternoon temperatures despite thin smoke aloft. Should see temperatures climb into the upper 60s by the afternoon. && .LONG TERM /THURSDAY THROUGH MONDAY/... Upper long wave trough off the coast with upper ridge building over the southeastern States through Friday as deep low moves out of intermountain west into the Northern Plains. Air mass will remain dry through Friday and temperatures will be above normal...highs in the lower 70s...due to ridge aloft. Models suggest a cold front will move through the region Saturday afternoon/evening. The latest guidance continues to point to a dry frontal passage due to limited moisture. Breezy conditions behind the front with moderately strong cold advection/modified Canadian air mass. Maximum temperatures mainly in the 50s Sunday and Monday despite strong isolation. Freezing temperatures possible Monday morning. && .AVIATION /04Z TUESDAY THROUGH SATURDAY/... Flight restrictions are expected at all terminals due to reduced visibilities in smoke and fog tonight. Smoke from wildfires over the southern Appalachians spread into area earlier today and has become trapped beneath the nocturnal inversion. Based on the HRRR smoke forecast and USFS BlueSky modeling, the smoke should persist through the night. In addition, conditions are favorable for fog formation due to elevated dew points, light winds, clear skies and dry air aloft. As a result, the TAFs indicate MVFR or lower visibilities in smoke through 06Z, then IFR or lower visibilities in fog enhanced by smoke from 06-15Z. The expectation is that some diurnal improvement should occur, and this is supported by some of the smoke modeling, so visibilities return to MVFR by 15Z and VFR by 19Z Tuesday. EXTENDED AVIATION OUTLOOK...Reduced visibilities in smoke/fog could continue through Wednesday. Lower VSBYS would be expected late night/morning, with some improvement in the afternoon due to mixing. && .CAE WATCHES/WARNINGS/ADVISORIES... GA...None. SC...None. && $$
Area Forecast Discussion
National Weather Service State College PA
1057 PM EST Mon Nov 14 2016 .SYNOPSIS... A weak storm system will move up along the east coast tonight and Tuesday. This will bring a chance of light showers to southeast Pennsylvania. Another weak disturbance will bring a chance of showers to NW Pennsylvania as well as a brief reinforcing shot of cooler air Wednesday. Temperatures will moderate once again by the end of the week as a ridge of high pressure returns to the eastern US. Temperatures will be well above average by the end of the work week. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/... BKN-OVC skies covering central PA late this evening with very light radar returns representing isolated areas of light rain reaching the ground over parts of the South Central mountains. Pops remain highest south and southeast overnight as slow moving upper trof over the Lower Ohio Valley and its mid Atlantic sfc low reflection move closer. HRRR runs still doing a good job showing precipitation decreasing in coverage and intensity as it moves northward into drier air, but there is enough moisture and lift to bring some light showers to SE zones overnight. QPF will be less than one quarter inch, but is welcome given how dry its been this fall. With milder airmass and more cloud cover overnight temperatures will be a little milder than last few nights. && .SHORT TERM /6 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/... Low pressure system moves into New England with decreasing clouds and pops west to east leading to a pleasant afternoon with temperatures again several degrees over average. A shortwave in westerly flow will approach NW CWA late Tuesday night with cloud cover increasing as well as the chance of light showers towards daybreak Wednesday. && .LONG TERM /WEDNESDAY THROUGH MONDAY/... After the low lifts NE of the region Tue night, the long wave trough will sharpen over the eastern CONUS through midweek with an embedded shortwave bringing a chance of showers Wednesday along with a brief reinforcing shot of cooler air. The progressive pattern will result in a big ridge returning for the end of the week along with moderating temperatures. After a dry Thursday and a very mild Friday (with temperatures climbing into the 60s), a new trough moving through the central US that will push a cold front through the local area this weekend. The models still disagree with the strength and timing of the front and the amount of rain that will occur with it - though timing of precip should be focused from late Sat into Sunday. What seems more certain is that the weekend will end with a shot of colder air (as 850MB temps drop some 15-20C) that will last at least into early next week in brisk NW flow. This will also bring mention of sct rain and snow showers to northern mtns and laurel highlands as high temps fall back into the 30s and 40s. && .AVIATION /04Z TUESDAY THROUGH SATURDAY/... A weak low pressure system near Cape Hatteras will track northward over the next 24 hours, bringing the chance of a few showers across Eastern Pa late tonight and Tuesday. However, dry low level air over the region should ensure a continuation of VFR conditions across all of Central Pa through Tuesday evening. Outlook... Wed...Showers/reduced cigs possible KBFD/KJST. Thu...AM low cigs/fog possible Western Pa. Fri...Patchy AM fog possible. Sat...PM showers/MVFR reductions possible. && .FIRE WEATHER... Dry conditions this afternoon with RH values quite low below 30 percent across the area. However winds are expected to be mainly under 10 mph. && .CTP WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...Ross NEAR TERM...Ross/DeVoir SHORT TERM...Ross LONG TERM...La Corte/RXR AVIATION...Fitzgerald FIRE WEATHER...
Area Forecast Discussion
National Weather Service Grand Rapids MI
649 PM EST Mon Nov 14 2016 LATEST UPDATE... Update/Aviation .SYNOPSIS... Issued at 318 PM EST Mon Nov 14 2016 Quiet weather and mild temperatures will continue through the rest of this week. Highs in the 50s Tuesday and Wednesday will warm into the low to mid 60s on Thursday and Friday. A strong cold front will move through this weekend, resulting in rain changing over to snow Saturday night. Lake-effect snow will be possible Saturday night into Sunday. Highs in the low 40s are expected Sunday and Monday, with lows near or below freezing. && .UPDATE... Issued at 649 PM EST Mon Nov 14 2016 I increased the fog to dense between US-131 and US-31 from Holland north late tonight into midday Tuesday. I did this based on the HRRR and RAP model both showing this and the models showing an area of higher dew points developing over the southern 1/3 of Lake Michigan that moves into the cooler air over the land as the front moves through. Winds will be light so this will not allow for much mixing initially. The fog should mix out by midday Tuesday. && .SHORT TERM...(This evening through Wednesday night) Issued at 318 PM EST Mon Nov 14 2016 A weak surface front will slowly slide into the area from the northwest tonight, but no precipitation is expected. Weak forcing and mid-level dry air will keep Central and West Michigan dry tonight. Winds will go light and variable late tonight with the surface trough over the area. An increase in low level moisture could result in more clouds, but the expansive area of low clouds evident on visible satellite across Wisconsin and Minnesota is not expected to sock in West Michigan overnight. With partly cloudy skies a large portion of the night, areas of fog could develop after midnight. A second cold front will push through Lower Michigan Tuesday evening and night. A more potent shortwave does dive southeast from northern Minnesota, but the deeper moisture and large-scale forcing will remain well north of the area. There is just a low chance for light rain across the northern forecast area Tuesday evening. With no significant push of cold air, temperatures will remain fairly steady through Wednesday. Highs generally in the mid 50s with lows in the upper 30s to low 40s. Upper ridging and surface high pressure build back in on Wednesday, resulting in more quiet weather and decreasing clouds. .LONG TERM...(Thursday through Monday) Issued at 318 PM EST Mon Nov 14 2016 Main forecast concern is the transition to colder temperatures and prospects for snow this weekend. Models are in good agreement showing a transition from rain to snow Saturday night. Prospects for snow accumulations look limited at this time and would have the best chance of occurring over higher elevations of Northern and Central Lower Michigan. Southwest Lower Michigan could see a dominant lake effect precipitation band extending onshore with the northwest winds. However, water temperatures are still very warm and and the plume of lake modified air spreading inland will feature wet bulb temperatures near or above freezing which should curtail snow accumulation near the lakeshore. There will be a pronounced cool down. Thursday and Friday feature highs in the lower to mid 60s which is about 20 degrees above normal. After the mix of precipitation ends early Sunday, highs Sunday and Monday should be around 40 which is slightly below normal. && .AVIATION...(For the 00Z TAFS through 00Z Tuesday evening) Issued at 649 PM EST Mon Nov 14 2016 Currently VFR with cirrus clouds and light south southwest winds. This will continue until the surface cold front comes through the area early to mid morning Tuesday. Since the front will be slow to move through and winds will be light and given the lake water temperature is in the mid 50s yet, I expect dense fog along the lake shore inland to US-131 from after 06z till around 15z. This means MKG will go LIFR late tonight into midday Tuesday. GRR may also see this a few hours later. With AZO, BTL, LAN and JXN not having as much lake air, they should only see MVFR fog Tuesday morning. All areas should be VFR by late afternoon. && .MARINE... Issued at 318 PM EST Mon Nov 14 2016 Waves will continue to subside with diminishing winds this evening and overnight. Winds from the southwest of 10-15 knots this afternoon will diminish to light and variable overnight. Conditions will become hazardous on Lake Michigan for small craft Tuesday night and continue Wednesday. Southwest winds of 15 to 20 knots will veer northwest after midnight Tuesday night as a cold front moves through. Waves are expected to build to 3-5 feet after midnight. && .HYDROLOGY... Issued at 318 PM EST Mon Nov 14 2016 Area rivers are below bankfull and levels are steady or slowly falling. A few gages in the Grand River and Kalamazoo River basins indicate slightly above normal base flow for this time of year. However, there is high confidence for dry conditions through Friday, which should allow area river levels and base flows to continue trending towards normal. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...None. LM...None. && $$ UPDATE...WDM SYNOPSIS...EBW SHORT TERM...EBW LONG TERM...TJT AVIATION...WDM HYDROLOGY...TJT MARINE...EBW
Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
956 PM EST Mon Nov 14 2016 .SYNOPSIS... High pressure will linger across the region until a dry cold front crosses from the west by the middle of the week. Deep layered and warm high pressure quickly returns Thursday with a vigorous cold front approaching the region late Saturday. && .NEAR TERM /THROUGH TUESDAY/... As of 1000 pm EST Monday: Smoke remains an issue overnight but also some pesky low clouds across central NC that may work their way westward into our eastern zones that will have to be watched. Overall made very few changes with the late evening update and most of this was to adjust hourly trends. Lowered overnight lows just a tad for the higher elevations and some areas in Henderson County (which still has an active Frost/Freeze program) may flirt with some frost, but right now think dewpoints are a little too dry. Otherwise, forecast soundings indicate that a strong inversion will develop this evening and overnight. Sfc smoke guidance indicates that some areas could see smoke concentration three times higher than this morning across the upstate. I will indicate vis decreasing overnight, falling into the 1-2 mile range late this evening and overnight east of I-77. Low temperatures are forecast to range from the mid to upper 30s across the NC mtn valleys and across the I-40 corridor, low 40s across the upper Savannah River valley. Tuesday, daytime mixing should yield improving vis by mid day, western Carolina sites may continue to see light restrictions in vis headed into the early afternoon. In fact, high temperatures are forecast to range generally 2-4 degrees warmer across the upstate and NE GA from values observed today. The peak mixing height may range around 5 kft, resulting in better ventilation tomorrow afternoon. I will indicate a transition from areas of smoke to patchy smoke during the afternoon. Mid afternoon RH values are forecast to fall into the low 30s east of the mtns. && .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/... As of 210 PM Monday: The upper trough will progress away from the Appalachians early in the period, giving way to a building ridge downstream of a major southwest Conus cyclone by the end of the period. Otherwise, dry surface high pressure and low level W/NW flow will continue to dominate through the period. No substantive improvement is expected in the ongoing wildfire situation during the short term, so smoke will continue to cause visby and air quality issues across at least the western half of the forecast area through the period, esp during the overnight and morning hours. Under the influence of rising upper heights, temps will warm to about 5 degrees above climo by Wed afternoon, and remain there through the period. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... As of 215 pm EST Monday, an amplified pattern will start off the medium range period Thursday night into Friday with a prominent trough translating across the plains states while a dominant ridge persists over the east. Heights will fall rapidly from the west Friday night, the surface cold front will cross the area on Saturday, and the primary upper trough will cross the region through Saturday night. Upper jet right entrance region divergence will arrive in the forecast area on Saturday to enhance forcing, but frontal zone moisture looks increasingly narrow. In addition, low level flow should veer quickly ahead of the front, and instability looks quite limited for any thunderstorm potential. Stronger northwest flow moisture will set up across the mountains Saturday night and linger through Sunday. 850 mb temps may bottom out at minus 6 to minus 8 C by 12Z Sunday, so there will be a chance of upslope snow showers in the northwest flow early Sunday. Deep layer northwest flow will persist behind the trough through Sunday night with the pattern flattening out through Monday. Expect above climo temps on Friday, falling to below climo temps Sunday into Monday. && .AVIATION /03Z TUESDAY THROUGH SATURDAY/... At KCLT and elsewhere: Update for KCLT has been to add MVFR vsby for FU, and also to add TEMPO for low clouds to the east that may make their way into the KCLT airspace (HRRR and RAP both indicating a few hours of IFR cigs). Otherwise no changes. Main issue through the TAF period will be vsby restrictions overnight due to smoke. Expect widespread MVFR and areas of IFR vsby, and especially right before sunrise cannot rule out patchy LIFR or VLIFR vsby with nearly calm winds in place and smoke settling across the region (especially for the Upstate TAFs). Expect slow clearing on Tuesday. Winds will swing around NW and W as high pressure shifts over the area. Outlook: A weak cold front will cross the region from the west by mid week, but with limited moisture. Smoke could persist at times in and near the mountain valleys given continuation of wildfires in the vicinity. Confidence Table... 03-09Z 09-15Z 15-21Z 21-00Z KCLT High 100% High 98% High 98% High 100% KGSP High 88% High 100% High 88% High 100% KAVL High 89% High 100% High 88% High 100% KHKY High 100% High 100% High 100% High 100% KGMU High 88% High 100% High 88% High 100% KAND High 100% High 89% High 88% High 100% The percentage reflects the number of guidance members agreeing with the scheduled TAF issuance flight rule category. Complete hourly experimental aviation forecast consistency tables and ensemble forecasts are available at the following link: www.weather.gov/gsp/aviation && .FIRE WEATHER... ight, forecast soundings indicate that a strong inversion will develop this evening and overnight. Sfc smoke guidance indicates that some areas could see smoke concentration three times higher than this morning across the upstate. On Tuesday, daytime mixing should yield improving vis by mid day, western Carolina sites may continue to see light restrictions in vis headed into the early afternoon. In fact, high temperatures are forecast to range generally 2-4 degrees warmer across the upstate and NE GA from values observed today. The peak mixing height may range around 5 kft, resulting in better ventilation tomorrow afternoon. Mid afternoon RH values are forecast to fall into the low 30s east of the mtns and mid to upper 30s across the mtns. Winds may increase from the NW between 5 to 10 kts across the ridges during the afternoon. A weak sfc lee trough should support a light WSW wind east of the mtns. Tue night-Wed, Slightly warmer and drier conditions are expected over the active fire areas during mid-week, with no chance of rain, max Ts in the mid/upper 60s expected Wed Thu afternoons, along with minimum RH generally in the 30 to 40 percent range expected. It should be stressed that relative humidity forecasts in the Planning Forecast (FWF) are averaged over a large area. Local effects, as well as fire activity itself can result in observed RH values much different than what is forecast. Please request spot forecasts for more precise forecast information. Poor dispersion conditions/reduced visibility in smoke are also expected to persist, esp during the overnight and morning hours. A mostly dry, sharp cold front will cross the region from west on Saturday. Winds will come up sharply from the northwest Saturday night and remain gusty through Sunday. This is further enhance fire danger this weekend. && .GSP WATCHES/WARNINGS/ADVISORIES... GA...None. NC...None. SC...None. && $$ SYNOPSIS...NED/SBK NEAR TERM...NED/TDP SHORT TERM...JDL LONG TERM...HG AVIATION...TDP FIRE WEATHER...
Area Forecast Discussion
National Weather Service Lincoln IL
900 PM CST Mon Nov 14 2016 .UPDATE... Issued at 857 PM CST Mon Nov 14 2016 A weak cold front is currently crossing the forecast area, with little fanfare as was anticipated. The associated cloud cover is minimal, and the most notable impact is a wind shift from southwest to northwest. Main concern overnight is if any fog will develop as the temperature/dew point spread decreases. Not much has happened thus far, and short-range guidance is suggesting a lower risk than it did earlier today. Still, given the good radiational cooling conditions and small T/Td spreads, will maintain current patchy fog in the forecast. Only minor hourly forecast tweaks are necessary at this time. && .SHORT TERM...(This evening through Tuesday) ISSUED AT 245 PM CST Mon Nov 14 2016 20z/2pm surface analysis shows a weak cold front extending from near Madison, Wisconsin to just east of Kansas City, Missouri. The airmass ahead of the boundary remains quite dry, although surface dewpoints have risen slightly into the lower to middle 40s across central Illinois this afternoon. As the front slowly edges eastward, mid/high clouds will be on the increase late this afternoon into the evening: however, a lack of deep-layer moisture will prevent any precip development. The front will gradually make its way to the Indiana border by 12z Tue. With dewpoints pooling in the 40s along the boundary and mid/high clouds expected to dissipate, patchy fog will likely develop overnight. HRRR has been consistently showing fog developing across the eastern two-thirds of the KILX CWA after 08z. Have therefore added patchy fog to the forecast everywhere along/east of the Illinois River. This will not be a good set-up for widespread or dense fog, so am only anticipating minor visby reductions. Once any early morning fog burns off, mostly sunny skies will prevail on Tuesday with afternoon highs topping out in the upper 50s and lower 60s. .LONG TERM...(Tuesday night through Monday) ISSUED AT 245 PM CST Mon Nov 14 2016 Unseasonably warm weather to be the main story through Friday as a strong storm system tracks across the upper Midwest, with much colder weather to follow for the rest of the forecast period. Upper level ridging forecast to amplify over the central U.S. in response to a powerful trof forecast to dig into the southern Rockies on Thursday. This should result in an increasing southerly flow over the Midwest late Wednesday and especially on Thursday helping to pump afternoon temperatures well into the 70s. 12z models very similar to the 00z solutions with the GFS the slowest to push the cold front through our area Friday evening, while the ECMWF had the boundary through southeast Illinois by mid-afternoon. Amplified pattern over the lower 48 lends credence to the slower GFS solution over the past few days so will continue to lean towards its forecast, which will result in slower cold frontal passage late Friday. As a result, it looks like a classic cool season severe weather threat for parts of the Midwest Friday afternoon into the evening hours. The shear profiles have never been an issue with this system, with 50-60 kts 0-6km bulk shear seen on just about any model you looked at over the past 3-4 day , but due to the meager moisture profiles depicted on the ECMWF, cape values have been low to non-existant. May see some showers and storms enter our far western counties Friday morning, but the main event, if there is going to be one, will be in the afternoon and early evening hours as the front sweeps across the area. The shower threat will begin to shift off to our east late Friday night as the mid level dry slot tracks across the forecast area. Wrap around moisture and strong cold advection will be the main weather story on Saturday with the more robust GFS suggesting some showers affecting our northern counties, while the ECMWF shifts the moisture further northeast away from our area on Saturday. Model consensus suggests the better threat for the light showers will be to our north and east on Saturday, so for now, will keep the area dry. However, gusty northwest winds and low level cold advection should keep afternoon temperatures in the 40s on Saturday with night-time lows dropping into the middle 20s. A chilly weather pattern looks to hold through the remainder of this forecast period before we see a warming trend set up for the Midwest a couple of days before Thanksgiving. && .AVIATION...(For the 00Z TAFS through 00Z Tuesday evening) Issued at 555 PM CST Mon Nov 14 2016 A weak cold front will push across central Illinois tonight. A dry frontal passage is anticipated, but a period of MVFR fog is expected later tonight until drier air filters in behind the boundary. Winds should average below 10 kts through the period shifting between southwest and northwest with frontal passage. Winds will start trending back westerly with time Tuesday. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...Bak SHORT TERM...Barnes LONG TERM...Smith AVIATION...Bak
Area Forecast Discussion
National Weather Service Nashville TN
1004 PM CST Mon Nov 14 2016 .UPDATE... FOR EVENING DISCUSSION. && .DISCUSSION... Approaching shortwave trough and cold front are looking a bit more potent than previously suggested by models, and have developed some showers this evening across the MS River Valley. Short term models like the HRRR have some developing precip along the upper vort max and cold front crossing the TN river around 09Z-12Z this morning, but have kept things dry for now as current shower activity is more isolated than models currently show. Adjusted temperatures slightly to better match cloud cover this evening, with colder temps over the Plateau and slightly warmer as you move westward. Other than that, no major changes, and will keep an eye on developing precip upstream for possible showers in western zones in the early morning. && .AVIATION... 00Z TAF DISCUSSION. Upper trough swinging across the area with frontal system in Missouri and Arkansas heading this way. System is moisture starved so not expecting to get any rain from it but do expect clouds to move in after midnight but should remain vfr through 18z Tuesday. Could still see some smoke along the plateau later tonight but much improved elsewhere over last 24 hours. boyd && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ DISCUSSION......Barnwell AVIATION........01/Boyd
Area Forecast Discussion
National Weather Service Raleigh NC
935 PM EST Mon Nov 14 2016 .SYNOPSIS... An upper level low and an associated area of low pressure will lift northeast away from the area tonight, followed by another upper level trough on Tuesday. An upper level ridge then will build east over the region. && .NEAR TERM /THROUGH TONIGHT/... As of 935 PM Monday... It appears the back edge of the low stratus has nearly stalled in the past few hours over the eastern Piedmont. The low level flow continued to be light NNE (cyclonic) over areas along and east of the Sandhills and eastern Piedmont. Even in the areas of the SW Piedmont around Wadesboro and Rockingham that were clearing, fog has rapidly developed. The latest HRRR and NAM near term forecasts support the current data in delaying clearing for much of the central and eastern part of our region until near or after sunrise Tuesday. This will keep temperatures up in the east (40s). A dense fog advisory may be needed as well over the areas of the SW into the central Piedmont (Anson and Richmond to Randolph/Chatham) if the current trends continue. We will indicate cloudy skies in the east, partly cloudy NW, and areas of dense fog SW into the central Piedmont. Previous discussion at 635 PM... The rain over the north-central Piedmont into VA has been decreasing in coverage to the point that there was only a few light showers left over near Roxboro at 650 PM. We will continue to eliminate the chance of any additional rainfall in the few counties across the north in the next few hours (should be all done by 900 PM). The back edge of the low stratus extended from near Southern Pines north to RDU and Henderson. The back edge of this low cloud deck was moving ENE, but slowly. Back to the west, very dry air was located just east of the Appalachians and Blue Ridge. However, with light winds it will take until late evening and overnight for the stratus to scour out. The center of the cool/stable pool left over from the rain today (from Orange and Vance counties NE into VA) should be the last to scour out. Otherwise, patchy fog can be expected in all but the western Piedmont where the current dry air resides, and where no rain fell today. && .SHORT TERM /TUESDAY THROUGH TUESDAY NIGHT/... As of 300 PM Monday... Cyclonic flow will continue aloft as yet another shortwave dives out of the upper Midwest and across the area, carving out a deeper longwave trough axis that will push east of central NC by Wednesday. Forecast soundings look too dry to wring out any precip some previous GFS/ECMWF runs showing such. Have used low level thicknesses to get forecast highs given little thermal advection, which are on the warmer side of statistical guidance, 64-67. Weak winds and mostly clear skies will allow for strong radiational for at least the first half of the night, with a light wind after midnight as the the upper trough moves overhead and the MSLP gradient tightens a little. Lows should reach the upper 30s to lower 40s. && .LONG TERM /WEDNESDAY THROUGH MONDAY/... As of 325 PM Monday... Fairly tranquil weather pattern expected to persist across central NC through the extended period. Temperatures initially will average close to normal then climb to above normal levels Friday and possibly Saturday before a much colder air mass overspreads the region by Sunday. An upper level trough along the eastern seaboard Wednesday will gradually lift/move east, allowing an upper level ridge anchored over the Gulf of Mexico to extend nwd into the Carolinas Thursday and Friday. This weather system will usher in a warmer air mass, leading to afternoon temperatures well into the 60s to around 70 on Friday. Forecast becomes more uncertain during the weekend as model timing differences very apparent with the ECMWF as much as 12-18 hours faster compared to the GFS. Both models depict a strong/deep upper level low over the western Great Lakes early Saturday. This system will likely grab the weather headlines the later half of the week as it has the potential to cause the first winter storm of the season over much of the northern Plains and upper Midwest. If ECMWF verifies, expect frontal passage early in the day Saturday. If GFS is more correct, frontal passage will not occur until late Saturday or Saturday night. Even if the ECMWF is more correct, cold air advection will likely be offset by downslope component of low level wind. For now will favor the slower timing, and project afternoon temps near 70-lower 70s over the se half of the forecast area. Colder air should overspread the region by Sunday, leading to afternoon high temps as much as 15-18 degrees cooler compared to Saturday afternoon. The cool air will linger into Monday. Atmosphere projected to remain quite dry for this time of year. In spite of the strong front, moisture very limited so expecting nothing more than a band of cloudiness with the front. If the dynamics aloft swing far enough south on Sunday, potential for an isolated shower or two to occur during the afternoon-early evening hours. Also, potential for windy conditions behind the front Sunday. If this materializes and the air mass dries out even further, yielding minimum RH values in the 20s, could see an increased fire danger threat across central NC. && .AVIATION /00Z TUESDAY THROUGH SATURDAY/... As of 658 PM Monday... VFR conditions at KINT/KGSO are expected to continue through the period. Low clouds remaining across the eastern half of the state should slowly begin to erode overnight as drier air enters the region in westerly flow. A period of clear skies would create conditions that would support the formation of sub-VFR visbys, though, as low dewpoint depressions will remain across this region overnight. VFR conditions should prevail across the entire area by late morning Tuesday. Outlook: Dry VFR conditions should through the remainder of the work week. && .RAH WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...SMITH NEAR TERM...Badgett SHORT TERM...SMITH LONG TERM...WSS AVIATION...30/SMITH
Area Forecast Discussion
National Weather Service Tulsa OK
917 PM CST Mon Nov 14 2016 ...UPDATE... .DISCUSSION... Have added a mention of fog across parts of northeast OK and northwest AR per recent HRRR output and where current dewpoint depressions are non-existant. Overnigh shift will need to continue to monitor for possibility of more widespread fog. && .PRELIMINARY POINT TEMPS/POPS... TUL 45 77 48 81 / 0 0 0 0 FSM 46 78 48 82 / 0 0 0 0 MLC 44 78 49 81 / 0 0 0 0 BVO 39 77 40 80 / 0 0 0 0 FYV 40 73 41 77 / 0 0 0 0 BYV 44 73 47 78 / 0 0 0 0 MKO 45 77 47 81 / 0 0 0 0 MIO 42 73 46 79 / 0 0 0 0 F10 46 78 50 81 / 0 0 0 0 HHW 48 79 50 82 / 0 0 0 0 && .TSA WATCHES/WARNINGS/ADVISORIES... OK...None. AR...None. && $$ SHORT TERM...18
Area Forecast Discussion
National Weather Service Albany NY
413 AM EST Tue Nov 15 2016 .SYNOPSIS... As a weak storm moves up the coast into New England, periods of light rain are expected during the day on today, especially for areas east of the Hudson Valley. With the clouds and expected rainfall, temperatures will be cooler than recent days. Behind this storm, temperatures will return to being above normal for the remainder of the week, with mainly dry weather. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... As of 413 AM EST...At 500 hpa, a broad upper level trough is located over the Ohio Valley into Pennsylvania. Meanwhile, a weak area of low pressure is located at the surface off the coast of Virginia. Although the atmosphere is currently rather dry over our area (PWAT values only 0.14 inches at Albany based on the 00z KALY sounding), there is plenty of moisture streaming northward off the eastern seaboard. The latest IR satellite imagery shows a band of deep moisture and even some convection with this band of clouds moving northward across the Gulf Stream and headed towards southern New England. Meanwhile, plenty of mid/high level clouds are in place over all of upstate New York and western New England as the upper trough continues to slowly move towards the area. KENX radar imagery shows some rainfall is just starting to get close to our far southern zones. It may take a little while to moisten up the lowest portion of the atmosphere, but some rainfall looks to begin across Dutchess/Litchfield Counties over the next few hours. The 07z 3km HRRR shows steady light rain will gradually overspread the region from southeast to northwest during the day today. It may take until the late morning or around noon to reach the Capital Region and areas north/west. The steadiest rainfall looks to occur during the afternoon hours, as the storm system moves across central/eastern New England. Although the bulk of the rainfall will be light, the HRRR suggests there could be some locally heavier downpours (mainly across western New England) as a 40 kt low-level jet (850 hpa u wind 2 to 3 STD below normal) combines with PWATs rising to around 1.00 inches (about 1 to 2 STD above normal). This rainfall is much needed, although cannot rule out some large puddles on area roadways and on streets in the urbanized areas of western New England where fallen leaves may clog drainage for this afternoon into the evening commute. With our area on the western fringe of the storm, the rainfall may be somewhat more spotty and lighter further west, such as across the western Mohawk Valley and Adirondacks. These areas may only see under a tenth of an inch of rainfall and much of the day may just wind up being cloudy and cool with a few periods of light rain. Temperatures today will be cooler than recent days with highs generally in the 40s. A few spots (such as in northwestern parts of the area) may see highs around 50. && .SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/... Steady rainfall in the evening will taper off to showers by late this evening into tonight as the low pressure area continues to lifts towards northern New England. Still, the upper level trough overhead and cyclonic flow in place could allow for a few additional rain showers, especially for northern and eastern parts of the area. It will remain cloudy overnight, as low-level moisture will be trapped beneath an inversion. Lows will only be in the mid to upper 30s. With the upper trough still overhead, there will be more clouds than sun for Wednesday, although some breaks will occur from time to time for valley areas. There could be a few additional light rain showers or sprinkles across western areas thanks to the passing upper level trough, but it should be dry for most of the day. Highs will be milder once again, with temperatures reaching into the 50s for valley areas. As the upper level through starts to slide eastward, strong upper level ridging will build into the area for the remainder of the work week, as a large area of surface high pressure dominates much of the eastern US. This will allow for dry weather with clearing skies for Wed night through Thursday Night. Temps aloft will be warming, allowing for above-normal daytime highs. Overnight lows on Wed/Thurs nights will generally be in the 30s and highs on Thursday look to reach the upper 40s to upper 50s across the area. Most spots will see highs of 5 to 10 degrees above normal. && .LONG TERM /FRIDAY THROUGH MONDAY/... Guidance is in agreement that the longwave pattern will be amplified across the CONUS through the period. A strong low pressure system is expected to have formed over the Plains and is forecast to be moving into the Great Lakes region as we close out the week and head into the weekend. It`s expected that high pressure across our region will be weakening as we are squeezed between the system moving across the Great Lakes and a storm located around 500 miles east of Montauk Point resulting in fair and mild weather; highs in the 50s and lows in 30s. It appears the Great Lakes system should occluded as its cold front moves eastward across the Northeast Saturday night into Sunday with showers, mainly rain, expected across the area. The uncertainty in the forecast grows as the upper trough is expected to become negatively tilted with an low developing over the region by late in the weekend and how it interacts with the offshore storm. The indications are the coastal storm will be drawn westward and will consolidated into a low over New England which should lift northward through early in the week. This set up will have cyclonic flow across the region drawing colder air across the relatively warm water of the Great Lakes resulting in lake enhanced rain/snow showers. Temperatures are anticipated to run below normal as we head into Thanksgiving weekend with highs only in upper 20s to lower 40s Monday along with brisk and gusty winds. && .AVIATION /09Z TUESDAY THROUGH SATURDAY/... An area of low pressure along the mid-Atlantic coast will move gradually northward and into New England this evening. Clouds will be on the increase thickening and lowering overnight into Tuesday morning. Rainfall associated with the low will overspread the TAF sites during the day with conditions lower to MVFR in the morning at KPOU, by afternoon at KPSF, in the early afternoon at KALB and by mid/late afternoon at KGFL. A period of IFR conditions are expected at KPOU and KPSF. The rain is expected to end from southwest to northeast during the evening hours with MVFR conditions lingering. Winds will be light/variable to calm overnight with a light north to northeast flow developing in the morning and continuing through much of the day with the winds diminishing in the evening. Outlook... Wednesday to Saturday: No Operational Impact. NO SIG WX. && .FIRE WEATHER... As a weak storm moves up the coast and into New England, a wetting rainfall is expected for many areas, especially east of the Hudson Valley. With clouds and rain today, RH values will only be as low as 55 to 75 percent, mainly for this morning before rain picks up in coverage/intensity. North to northeast winds will be 5 to 10 MPH. RH values will stay elevated tonight with light winds. On Wednesday, clouds will break for some sunshine, mainly for valley areas. RH values will fall to 50 to 65 percent in the afternoon with west winds of 5 to 10 MPH. && .HYDROLOGY... A storm system moving up the coast to the east of the region will bring some rain today into this evening, especially between the late morning and afternoon hours. Most areas will see between a quarter to half inch of rain, although the western Adirondacks may see slightly lower amounts. A few spots in western New England may see up to an inch of rain thanks to some locally heavier downpours. This rainfall is much needed due to the recent very dry conditions. Some smaller rivers/streams may have very minor rises, but for the most part, flows will hold steady following this much needed rainfall. Although a stray lingering shower can`t be ruled out for western areas on Wednesday, dry weather will return for Wednesday night through Saturday. Another chance of rain will arrive with another frontal boundary for Saturday night into Sunday. The US Drought Monitor continues to have much of the area in the D1 (Moderate Drought) to D2 (Severe Drought) categories. This rainfall is helpful, but probably not enough to significantly change these classifications this week. For details on specific area rivers and lakes, including observed and forecast river stages and lake elevations, please visit the Advanced Hydrologic Prediction Service /AHPS/ graphs on our website. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. MA...None. VT...None. && $$ SYNOPSIS...Frugis NEAR TERM...Frugis SHORT TERM...Frugis LONG TERM...IAA AVIATION...IAA FIRE WEATHER...Frugis HYDROLOGY...Frugis
Area Forecast Discussion
National Weather Service Bismarck ND
334 AM CST Tue Nov 15 2016 .SHORT TERM...(Today and tonight) Issued at 334 AM CST Tue Nov 15 2016 Quiet and mild weather continues today and tonight under the influence of broad 500-mb ridging across the northern Plains. Early day moisture channel (water vapor) imagery shows a short wave trough moving through central Manitoba, and 00 UTC upper- air analyses revealed an intense 150 kt 300 mb jet core on the equatorward side of that wave from Seattle, WA to Glasgow, MT. Forcing in the left-exit region of that jet streak drove high- based shower activity in our area overnight, but that maximum in high-level winds is forecast to weaken by daybreak. Radar trends and HRRR simulations concurrently suggest the lingering shower activity in east central ND will exit the area before 12 UTC as a weak cold front also completes its passage through the area. For today, we expect clearing skies thanks to subsidence tied to weak height rises aloft and surface high pressure, which will be in firm control today as it slowly crosses the area. Mixing may be somewhat limited under the surface high, so temperatures are more apt to fall in line with the 00 UTC multi-model consensus than on previous days. We nonetheless tipped our hats slightly in favor of warmer MOS guidance in respect to the sunshine, snow- free ground and drying soils, and recent model biases related to the latter conditions. Forecast highs thus range from the upper 40s F along the Canadian border to the upper 50s along the ND-SD state line. Tonight, a relatively rapid temperature fall is likely to occur this evening even though the 00 UTC model consensus places the surface high over the eastern Dakotas by that time. Low-level drying today beneath the high and dry soils will likely favor a temperature fall that`s greater than the model consensus, which we have experienced several times in the last week. We therefore relied on the cooler edge of the 00 UTC model guidance set to build tonight`s temperature forecast, which calls for lows from the upper 20s to lower 30s F. That being said, cloud cover will likely increase through the night and combined with a ramp-up in warm air advection, there is some uncertainty in our move to use some of the colder guidance for the forecast. Finally, low PoPs are being carried in the north tonight where the mid-level warm air advection will be focused. .LONG TERM...(Wednesday through Monday) Issued at 334 AM CST Tue Nov 15 2016 All eyes remain on the possible late-week storm system which we have been advertising with a cautious tone the last several days due to the large degree of uncertainty in the details associated with its evolution. However, our confidence is slowly growing as the late week period moves inside the initial-condition-dominated predictability horizon of model guidance. More to the point, our confidence is slowly increasing that the heaviest snowfall and strongest winds with the late-week system may end up south and east of most of western and central ND. Looking back at the last 24 hours of global model guidance, it appears there`s a convergence toward a more common solution with regard to the timing and path of the 700 to 500 mb lows that have been forecast to develop on the High Plains Thursday night and then eject northeast to the western Great Lakes by Friday night. The 00 UTC GFS made a significant shift south and eastward with those lows, taking the 500 mb circulation from Norfolk, Neb at 12 UTC Friday to Eau Claire, WI by Friday evening. The 00 UTC ECMWF remained the fastest model simulation (and indeed is a fast out- lier compared to the 12 UTC ECMWF ensemble members), but its mid- and upper-level low tracks were relatively similar to the GFS, if only a touch further southeast. There was also a significant shift in the 00 UTC GFS ensemble members at points over western and most of central ND toward a drier scenario, also suggesting that model guidance is beginning to "lock in" to a common idea that may well be an accurate one. As an example of that shift, at Bismarck, the 12 UTC GFS ensemble mean event-total QPF was around 0.60 inches, but only one member of the 00 UTC GFS ensemble pack produced that much QPF. The GFS ensemble mean at Bismarck is now only near 0.15 inches. Assuming an average 13 to 1 snow-to-liquid ratio, which is reasonable since forecast thermal profiles with this system have never been simulated to be cold enough for more than a small layer in the favored dendritic growth zone, that means the GFS ensemble mean has shifted from a potential 8 inch snowfall to a potential 2 inch snowfall at Bismarck as that particular ensemble system`s most probable scenario. Our official forecast followed the global model trends, and in fact since the simulations are also trending faster with the wave passage, we actually have a dry forecast in place during the day Friday over western and parts of central ND. The highest chance of snow will be Thursday night over most of the area per the 00 UTC multi-model consensus, It appears that the shift and convergence in model simulations is due to increasing sampling of the upper wave that was off of the Alaskan Peninsula at 00 UTC. Moreover, from the standpoint of teleconnections, recent in-house research has suggested an area of positive 500 mb height anomalies should be observed north of Alaska, but on this side of the globe, and downstream off of the coast of Newfoundland, about 5 days before a western or central ND blizzard. Currently-observed anomalies are a close, but not exact fit to those teleconnections, which also may favor a close call, but not a direct impact to the local area. Of course, we`re not ready to make a final call on this situation yet, and even the 00 UTC multi-model consensus suggests headline-worthy snowfall may impact the James River valley and perhaps south central ND, so we are still urging everyone to check back with later forecasts. Otherwise, the weather will quickly quiet down again this weekend and into early next week, though it will be much colder with lows in the teens very probable this weekend. A warming trend is then forecast to resume by early next week. && .AVIATION...(For the 06Z TAFS through 06Z Tuesday night) Issued at 334 AM CST Mon Nov 14 2016 VFR conditions are forecast for the 06 UTC TAF cycle. Scattered light rain showers will exit east central ND by 11 UTC as a weak cold frontal passage occurs. Expect clearing of current mid- and high-level ceilings this morning, leading to a mostly sunny day. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...CJS LONG TERM...CJS AVIATION...CJS
Area Forecast Discussion
National Weather Service Columbia SC
318 AM EST Tue Nov 15 2016 .SYNOPSIS... Dry high pressure will extend into the area from the west through Friday with above normal temps. A dry cold front will come through Saturday, reinforcing dry conditions with cooler temps for the weekend and into next week. && .NEAR TERM /THROUGH TODAY/... Early this morning...Strong radiational cooling combined with enhanced low level moisture beneath dry mid levels has resulted in some fog across the region. Visibilities have also been reduced by smoke from the wild fires over the southern Appalachians. A dense fog advisory may be needed for the eastern portion of the area later but confidence is low because stratus clouds are also developing which could prevent the dense fog from maintaining or forming. Smoke model forecasts show concentrations of smoke increasing through the predawn hours so will continue the mention of areas of smoke in the weather grids. Temperatures early this morning are on track to with lows in the upper 30s to lower 40s. Today...An upper trough will remain over the eastern part of the country today while high pressure ridges into the area at the surface. A relatively dry airmass will be over the area with precipitable water values near half an inch. Skies will be mostly sunny this afternoon. Smoke from the fires over the southern Appalachians will spread into the area during the day, but should see some diurnal improvement based on the HRRR. Downsloping winds should result in mild afternoon temperatures despite thin smoke aloft. High temperatures are forecast in the upper 60s to lower 70s. && .SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/... Overnight, the axis of the upper trough will push east of the area and off the coast by morning. At the surface, high pressure will continue to be centered west of the area. Winds through the lower layers of the atmosphere will be light, but generally out of the west through the period. Because of this windflow pattern, the region will be experiencing some lingering smoke from the southern Appalachian fires. This will lead to smoky and hazy conditions. Airmass will be dry tonight, and do not expect any widespread fog formation with the smoke. Should see temperatures tonight and Wednesday night in the lower 40s. Downsloping winds during the day on Wednesday, along with plenty of sunshine, will help to bring temperatures during the afternoon back up into the lower 70s. && .LONG TERM /THURSDAY THROUGH MONDAY/... Models in good agreement through Friday with building an upper level ridge into the southeastern United States. At the surface, the center of high pressure will be across the forecast area by Friday. Airmass will continue to be dry through Friday night. Temperatures will be above normal, with highs in the lower 70s. Models suggest a cold front will move through the region Saturday afternoon/evening. It still appears as if moisture will be limited with the frontal passage. Slight chance pops across the north at best, with most areas remaining dry with this front. Breezy conditions behind the front with moderately strong cold advection pattern. Maximum temperatures mainly in the 50s Sunday and Monday despite strong isolation. Freezing temperatures possible Monday and Tuesday Mornings. && .AVIATION /08Z TUESDAY THROUGH SATURDAY/... Flight restrictions are expected at all terminals due to reduced visibilities in smoke and fog. Smoke from wildfires over the southern Appalachians spread into area on Monday and has become trapped beneath the nocturnal inversion. Based on the HRRR smoke forecast and USFS BlueSky modeling, the smoke should persist through the early morning hours. Fog has also developed due to elevated dew points, light winds, clear skies and dry air aloft. As a result, the TAFs indicate MVFR or lower visibilities in smoke through 06Z, then IFR or lower visibilities in fog enhanced by smoke from 06-15Z. The expectation is that some diurnal improvement should occur, and this is supported by some of the smoke modeling, so visibilities return to MVFR by 15Z and VFR by 19Z. Restrictions may return to the terminals in smoke tonight although confidence is low at this time. EXTENDED AVIATION OUTLOOK...Reduced visibilities in smoke/fog could continue through Wednesday. Lower VSBYS would be expected late night/morning, with some improvement in the afternoon due to mixing. && .CAE WATCHES/WARNINGS/ADVISORIES... GA...None. SC...None. && $$
Area Forecast Discussion
National Weather Service Quad Cities IA IL
357 AM CST Tue Nov 15 2016 .SYNOPSIS... Issued at 330 AM CST Tue Nov 15 2016 At 2 am, the weak cold front that pushed through the local area Monday extended from southern Lake Michigan south across eastern IL. In its wake, there was a light NW flow and weak cold air advection pulling in a slightly cooler airmass. Satellite imagery showed a trailing axis of low clouds over WI into east central IA, while upstream, clear skies under a weak surface ridge axis over central IA into southern WI, has lead to widespread fog. This fog was beginning to develop over eastern IA, but so far the combination of the passing stratus deck and NW winds around 6 to 8 kts has kept visibilities mainly in a 3 to 5 mile range outside the quarter mile reported just north of our forecast area in Olwein. && .SHORT TERM...(Today and Tonight) ISSUED AT 330 AM CST Tue Nov 15 2016 Initial focus is on the potential for dense fog early this morning, then attention turns to temperatures. The HRRR surface visibility fields and SREF visibility probs suggest the greatest potential for dense fog this morning will be over east central IA, mainly northwest of a line from roughly Sigourney to Monticello around 4 am to 9 am. Conceptually, this makes sense as this area will be closest to the approaching ridge and associated weakening wind fields and radiational cooling under the pocket of clear skies. Have added patchy fog for now and issued a special weather statement patchy dense fog through the morning commute. Will continue to monitor for the need for an advisory early this morning. Satellite imagery shows an area of dissipating high clouds topping the upper ridge axis from the northern plains into NW IA rapidly spreading E-SE. This may hamper the on-going radiational cooling and makes the fog forecast more challenging. Later today, the ridge axis slides overhead, providing light winds and mostly sunny skies. Highs will be only slightly lower than Monday as the initially cooler airmass will be offset by a light southerly return flow by afternoon. Tonight, another weak, dry front pushes through in the evening with the ridge axis building back overhead by morning. Fog is again suggested by the SREF under the eastern side of the ridge axis over NW IL and have added patchy fog wording toward sunrise. Much like tonight, will see mins from the mid 30s to lower 40s under the mostly clear skies. .LONG TERM...(Wednesday through Monday) ISSUED AT 330 AM CST Tue Nov 15 2016 Overview: After near record highs on Thursday, a pattern change to cooler weather is likely by this weekend continuing into next week. Wednesday and Thursday: Very warm for the middle of November in the 60s on Wednesday, then upper 60s to mid 70s on Thursday (see Climate Section for the daily records). Suite of models have a 995-1000mb sfc low tracking through western or central Iowa on Thursday. Regardless of the exact strength and track, E Iowa/NW Illinois will be in the warm sector of this system with 850mb temps surging into the 14-18 C range or 2 standard deviations above the mean. Consequently, it`s going to be breezy - southerly winds sustained 20-25 mph with gusts of 30-35 mph. The highest winds are forecast along and south of I-80. Friday and Saturday: Most significant weather impacts will be the strong winds, and the much cooler temps by Friday night/Saturday. Forecast highs on Saturday are in the lower 40s south to upper 30s north. Precipitation: The sfc low is forecast to move into NW Wisconsin on Friday bringing heavy precip to parts of Minnesota and Wisconsin; however, significant precipitation is not expected for E Iowa/NW Illinois because the low- level jet is veered to the WSW causing less than optimal WV transport along the cold front. The eastern CWA stands the best chance for showers and isolated storms Friday morning into the early afternoon before a mature dry-slot punches into the region from the SW as it wraps into the center of the low. On the backside of the low, wrap around snow showers or flurries are likely, especially across the NE half of the area with the Quad Cities on the edge. No accumulation is expected at this time. Winds: WSW winds during the day Friday will veer to westerly overnight. For now, trended SuperBlend toward raw model consensus which yields 20-25 mph sustained winds and gusts of 30-35 mph with potential for occasionally gusts near 40 mph. On Saturday, as the sfc low reaches the Northern Great lakes, a strong pressure gradient will reside to the W/SW. Cold air advection/isentropic downglide should foster deep dry adiabatic profiles extending from the sfc to above 850mb. There is some model uncertainty at this lead time, but based on a conceptual model appropriate to this synoptic setup, potential is there for gusts over 40 mph, especially late Friday night into Saturday afternoon. GFS forecast soundings mix up into 50 kt winds, something to monitor through this week. Sunday through Tuesday: Below average temps in the 30s and 40s Sunday and Monday with lows in the 20s and upper teens most areas. ECMWF/GFS differ with respect to timing and track of the next area of low pressure Tuesday of next week. ECMWF is faster and further north. Too early to say much else, except that there may be another trough in the Midwest. Uttech && .AVIATION...(For the 06Z TAFS through 06Z Tuesday Night) ISSUED AT 1139 PM CST Mon Nov 14 2016 Generally VFR conditions expected through the TAF cycle. Some patchy fog with will be possible toward daybreak, for mainly portions of east central and northeast Iowa especially in low lying areas where winds will diminish ahead of a high pressure ridge building in. Have mentioned light fog at CID being closest to the ridge axis and lower temp/dewpt spreads... and have left out mention elsewhere for now where confidence is low being further east from the ridge within light northwest flow. Some low clouds will be found overnight into Tuesday morning, but any cigs look to remain VFR and should be confined mostly n/ne of CID-MLI. Otherwise, just some mid and high level cloudiness at times throughout the TAF period. Winds will turn from the southwest by Tuesday afternoon at 5-15 kts then shift to northwest Tuesday night with passage of a surface trough. && .CLIMATE... ISSUED AT 243 AM CST Tue Nov 15 2016 Record Highs for November 17... Moline.........74 in 1941 Cedar Rapids...73 in 1941 Dubuque........71 in 1941 Burlington.....75 in 1952 && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ SYNOPSIS...Sheets SHORT TERM...Sheets LONG TERM...Uttech AVIATION...McClure CLIMATE...Uttech
Area Forecast Discussion
National Weather Service Grand Forks ND
359 AM CST Tue Nov 15 2016 .SHORT TERM...(Today and tonight) Issued at 359 AM CST Tue Nov 15 2016 Shower chances this morning and then temperatures will be the main challenges for the period. A fairly vigorous shortwave currently moving through the Red River Valley has helped produce rain showers. The showers have been quite a bit further south than originally expected, with most of the activity spreading from the central and southern Red River Valley into west central MN. The HRRR seems to have a decent handle on current radar trends so followed it fairly closely for the early morning hours. Think that our showers should exit off to the east by 15Z or so this morning. After the shortwave moves off to the east, we should have some clearing skies later today, along with northwesterly winds picking up on the backside of the surface trough. Some cold air advection, but it is pretty weak and will be offset by sunshine. Will continue to keep highs in the upper 40s to 50s across the CWA. After some brief surface ridging this evening, winds will shift back to the south tonight ahead of the next shortwave. The winds along with increasing cloud cover will help keep temps in the 30s although the eastern tier could see a few spots in the upper 20s with lighter winds and clear skies a bit longer. .LONG TERM...(Wednesday through Monday) Issued at 359 AM CST Tue Nov 15 2016 Wednesday through Thursday...Flow will start to become more southwesterly on Wednesday as an upper ridge moves east. Weak shortwave over the top of the ridge could bring some light rain near the international border, but think that most of the precip will be in Canada. By Thursday, the large upper trough will be moving into the southern Rockies, then lifting into the central Plains Thursday night. While trends have been further south and east with the system, there is still considerable variation in how the models handle the track of the surface low. Will continue to keep high POPs and QPF over our southern counties, and with cold temperatures coming along the backside of the low on Thursday night, a changeover to snow will be likely. It will just be a question of where the heaviest band falls. Friday...Model spread still showing a wide range of possible precipitation totals across the area. The trend in the solns has shifted to the south and east as the more progressive ECMWF suite continues to lead with the Canadian and even the 06Z NAM catching on to this idea. During the day on Friday the 00z GFS operational run indicates a stronger period of snowfall with q-vector divergence lining up with frontogenetical forcing to create a stronger band of snow on the back side of the system impacting west central MN and the far eastern zones of the FA. As a result the spread of solns across the east remains very large, leading to low confidence in totals. Wheres the spread in the northern valley and DVL basin has reduced, increasing confidence for less impactful event. Saturday to Monday will see an overall dry period as 500mb flow transitions from the aforementioned storm system/trough to ridging by Sunday. Another short wave will bring weak PoPs to the area Monday with highs generally in the 30s and lows in the teens and 20s, which is quite normal for the third weekend of November. && .AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon) Issued at 1229 PM CST Mon Nov 14 2016 VSBY improving however ifr/lifr CIGS continue from valley east. With winds becoming more sw expect improving conditions through the afternoon to VFR by mid afternoon. Once clouds lift expect vfr conditions through the remainder of the period. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...None. MN...None. && $$ SHORT TERM...JR LONG TERM...JR/JK AVIATION...Speicher
Area Forecast Discussion
National Weather Service Wilmington NC
448 AM EST Tue Nov 15 2016 .SYNOPSIS... A weak low pressure near the North Carolina coast will move away from the area tonight. High pressure will build in from the west Tuesday through Thursday, moving overhead Friday with mild temperatures. A dry cold front will move through the area Saturday, followed by much cooler weather for early next week. && .NEAR TERM /THROUGH TONIGHT/... As of 330 AM Tuesday...Dense fog advisory in effect for all areas thru 9 am this morning. This morning will start out with mainly foggy conditions across the entire ILM CWA. The fog will likely be densest across the ILM SC CWA this morning. This a result of the low stratus deck from earlier having scoured and/or moved out of this area. Across the ILM NC CWA, the low stratus cloud deck continues and is slower to erode and has kept the fog from becoming dense. However, latest IR 11-3.9 micron channel indicates the stratus deck is thinning and also moving off the coast. As a result and for the remainder of this morning, have indicated areas of fog, with patches of dense, across the ILM NC CWA. Using the hourly NAMBUFR soundings, the low level inversion should break during the mid to late morning hours. Once it does, the fog and low clouds will scour out and dissipate leaving a mostly sunny sky by midday. The FA remains under troffiness aloft with the upper trof axis progressing overhead by daybreak Wednesday. At the sfc, weak high pressure will extend across the area. Lack of any sfc pg, will keep winds 5 to 9 kt during the day and nearly calm for tonight. Some drying will occur this aftn but will not be enough to prevent fog development tonight. Model soundings for tonight indicate a sfc based inversion to develop after sunset. Winds will decouple and skies to remain mostly clear, giving rise to decent rad cooling conditions. Progged soundings indicate fog, and not low stratus, will become the nights nemesis to motorists and aviators. Various model mos guidance indicates max/min temps this period will be near normal. An Air Quality Alert message has been issued and involves 5 of the ILM SC counties. This is at the request of the SOUTH CAROLINA DEPARTMENT OF HEALTH AND ENVIRONMENTAL CONTROL and is valid thru midnight tonight. The reason for this message is due to smoke emitted by the Appalachian Mountain wildfires being picked up and transported to the east. There will be some mixing and dilution occurring prior to this air reaching the 5 ILM SC counties. However, the fine particulate concentration level as it crosses these 5 counties still may approach or exceed unhealthy standards. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... As of 400 AM Tuesday...The upper trof line will push off the Carolina Coasts during Wednesday. Amplified upper ridging will follow and affect the FA thru Friday Night. The south to north upper ridge axis will reach the western Carolinas by late this period. Any further progression eastward will depend on the movement of the expansive cutoff low that develops over the adjacent offshore Atlantic waters. At the sfc, a 1025+ mb high pressure system will affect the area thruout this time period. The high`s broad center will nearly be overhead by late Thu thru Friday. Skies will be clear or mostly clear thruout this period with possible high level moisture moving overhead by late Fri due to the upper ridge axis nearly overhead. Max temperatures this period will run near 70 at the beaches, and in the 70s inland. Overnight lows mainly in the 40s with a few 50s at the beaches. Only wx feature to watch out for will be the possibility of fog, possibly dense, occurring each morning. This a result of excellent rad cooling conditions and enough low level moisture avbl. && .LONG TERM /FRIDAY THROUGH MONDAY/... As of 300 AM Tuesday...Amplified ridge but with short wavelength will be sandwiched across the East Coast Friday into Saturday before being displaced by a deep upper low the latter half of the extended. Friday and Saturday will feature above normal temperatures in the 70s with abundant sunshine. However, a significant cold front approaching from the NW will being to spread cloudiness overhead during Saturday. This front will dive across the Carolinas Saturday night beneath the aforementioned upper low moving across the Mid- Atlantic states. Strong cold advection will accompany this front, but rainfall will be tough to achieve due to weak pre-frontal moist advection. The stronger ECM does paint a few showers, especially northern zones, Saturday night, so will continue with a SCHC for POP, although this will remain sub-mentionable for D5/D6. Thereafter, 850mb temps plummet to below zero and surface temps will crash to well below normal Sunday and Monday, and freezing minimum temperatures are possible. && .AVIATION /10Z TUESDAY THROUGH SATURDAY/... As of 06Z...High confidence in IFR/LIFR through the overnight at all terminals. Broad trough of low pressure extending back from a surface low off the VA coast is maintaining weak NE winds at the surface while high pressure builds east from the Gulf Coast. SW flow atop this cool NE flow is creating a very steep inversion, keeping moisture trapped beneath it. Satellite imagery this morning shows widespread stratus and fog expanding across the area, and expect all terminals to drop to IFR or lower overnight. Local UPS fog procedures echo the HRRR visibility forecasts for widespread fog, some of which is likely to become 1/4SM or less. This will occur in conjunction with low stratus at LIFR levels, and landing minimums may be exceeded tonight at some of the local airports, most likely LBT and FLO. This fog/stratus will be very slow to burn off Tuesday morning, and IFR may persist well after daybreak before slowly eroding as the drier air within high pressure builds down and breaks the inversion. Winds through the period will be light and variable, although a predominantly W/NW flow will develop late in the valid period. Extended Outlook...VFR. A cold front may bring a few showers Saturday. && .MARINE... NEAR TERM /THROUGH TONIGHT/... As of 330 AM Tuesday...Weak high pressure to prevail across the area waters this period. The progged sfc pressure pattern will yield mainly a W to NW wind direction. The sfc pg will remain loosened and this will yield 10 to 15 kt early this morning across the outer waters, dropping to around 10 kt or less this aftn thru tonight. Significant seas will run 2 to 3 ft today and drop to around 2 ft tonight. The seas will be a combination of a 6 to 7 second period ese pseudo ground swell and a 3 to 4 second period wind waves. SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... As of 400 AM Tuesday...Wednesday will be another benign winds and significant seas day with NW winds 10 kt or less and 2 foot seas. A weak boundary moves across the waters Wednesday night. Much stronger high pressure will follow for Thu thru Thu night with the center of the high remaining west of the area waters. The sfc pressure pattern and semi tightened gradient will yield N to NNE winds around 15 kt initially on Thu then drops back to around 10 kt or 10 to 15 kt Thu night. Significant seas will run 2 to occasionally 3 ft. The ESE 1 to 2 foot ground swell at 8 to 9 second periods will dominate Wednesday, then mix with 3 to 5 second period wind waves on Thu. LONG TERM /FRIDAY THROUGH SATURDAY/... As of 300 AM Tuesday...Broad high pressure along the coast Friday will shift offshore ahead of a cold front which will cross the waters during Saturday. Winds ahead of this front will initially be from the North around 10 kts before briefly turning to the W/SW early Saturday as the high shifts offshore. Gusty NW winds will follow the FROPA beginning late on Saturday, with speeds increasing to 15-25 kts. Seas of 2-3 ft early Friday will fall as the high moves overhead, but then increase quickly with the gusty winds Saturday night up to 3-5 ft. An SCA may be required beginning late Saturday and extending beyond this period. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...Dense Fog Advisory until 9 AM EST this morning for SCZ017-023- 024-032-033-039-053>056. NC...Dense Fog Advisory until 9 AM EST this morning for NCZ087-096- 099-105>110. Coastal Flood Advisory until 9 AM EST this morning for NCZ106- 108-110. Coastal Flood Advisory from 8 AM this morning to noon EST today for NCZ107. MARINE...None. && $$ SYNOPSIS...JDW NEAR TERM...DCH SHORT TERM...DCH LONG TERM...JDW AVIATION...JDW
Area Forecast Discussion
National Weather Service Marquette MI
504 AM EST Tue Nov 15 2016 .SHORT TERM...(Today and tonight) Issued at 503 AM EST TUE NOV 15 2016 WV imagery and RAP analysis indicated a mid/upper level ridge from the sw CONUS into the wrn plains resulting in wnw flo from srn Canada to the nrn Great Lakes. An upstream shortwave trough extending from srn Manitoba into ern North Dakota supported areas of light rain from nw Ontario into nw MN. At the surface, a trough extended into the ern Dakotas from low pres over over nrn Manitoba. IR loop and sfc obs showed extensive low clouds over Upper Michigan as abundant low level moisture persists over the region as a weak ridge with mid level drying moves over the area. Today, although the strongest 700-300mb qvector conv with the shortwave moving into the region will remain to the north of the cwa, expect that it will be strong enough to support sct showers into the west by late morning and through cntrl Upper Michigan during the afternoon. However, rainfall amounts will be light, generally less than a tenth of an inch. With weak WAA into the afternoon, max temps will remain above normal with highs around 50. Tonight, expect the showers over the east half of the cwa in the evening to move out between 03z-06z. With partial clearing late over the west, temps could drop to near 30. Otherwise, the clouds will keep min readings generally in the mid 30s to around 40. .LONG TERM...(Wednesday through Monday) Issued at 346 AM EST TUE NOV 15 2016 A zonal Pacific airflow wl continue the relatively warm and mainly dry wx for Wed into Thu. But later in the week the pattern is expected to amplify, as a stronger disturbance/low pres system lifts ne from the Four Corners region and brings in some pcpn on Fri and likely some accumulating lake effect snow in its wake next weekend. Wed/Thu...Large scale ridging/subsidence in the wake of Tuesday`s departing shortwave wl bring a drying trend by Wed. As the sfc ridge axis shifts to the e on Wed and the wind shifts to the sw, increasing waa clouds are expected later Wed into Thu but dry conditions will persist. Unseasonably warm Pacific air wl continue to dominate during this time with h85 temps rising as high as 6-8C Wed night into Thu. Fri into Sun...Longer range models continue to display some variability on the track...timing and intensity of the shortwave/sfc low pres emerging from the Four Corners region of the CONUS and tracking ne thru the Plains and toward the western Great Lakes. The GFS model after showing good run-to-run continuity on a slower solution the past several days has now trended 6-12 hours quicker on its 00z run taking the sfc low through western Upper Mi Fri evening/early overnight and then into central Upper Mi by 12z Sat. The 00z GFS still remains about 12 hours slower than the 12z ECMWF run, but both indicate a similar storm track. The Canadian model run has also trended farther west on its 00z run and shows a similar track/timing than the 00z GFS although it is slightly farther east. Given that the models appear to be converging on a similar track, forecast confidence increases although timing of system remains in question, and will affect timing changeover from rain to snow. Given quicker timing trend of the 00z GFS would expect the bulk of synoptic pcpn to be mostly in form of rain for our area late Thu night into Fri evening, but then expect a quicker transition to lake enhanced/lake effect snow for late Fri night in the far west and across the rest of the cwa Sat morning into early afternoon as instability increases dramatically with h85 temps dropping as cold as -15c by late Sat night into Sunday. Several inches of lake effect snow accumulation in the northwest wind snow belts of Lake Superior certainly looks possible from late Fri night into Sunday morning before the snow tapers off from west to east on Sun with weakening cyclonic northerly flow and increasing ridging/subsidence from the north and west. Would not be surprised if some counties in nw snowbelts push advisory criteria snowfall of 4 or more inches in a 12 hour period. Heaviest snow looks like it would occur from late Fri night into Sat for the western counties and Sat into early Sunday for the rest of the cwa. Along with the potential for the first widespread accumulating snow of the season, the other big part of the story with this storm system will be the wind and cold. With the influx of cold air beginning in the far west late Fri night and spreading east on Sat, the corresponding increase in instability will also increase mixing to allow for strong and gusty nw winds to develop. GFS soundings indicate the potential for a period of storm force winds over the east half and north central portions of Lake Superior from mainly Sat afternoon through Sat evening. High wind warning criteria gusts to near 60 mph would also be possible from over the tip of the Keweenaw Peninsula to Lake Superior shoreline areas east of Marquette over roughly the same time period. A period of wind advisory gusts of 45 to 50 mph seem a good bet across much of the rest of the cwa from Sat into Sat evening. The combination of the snow, falling temps and strong winds will be a rude awakening after the above normal fall temps experienced thus far, and headlines will likely be needed across much of the region. Also expect wind chills to plummet through the teens over the west half Sat afternoon and across the entire U.P. on Sat night. Sun night into Mon...Lake effect snow and nw winds will continue to slowly diminish through this period as gradient slackens on backside of departed storm system and sfc ridge axis continues to move in from the west. Lake effect snow will hang on longer over the east half of the cwa due to slower diminishment of nw winds and longer fetch across the eastern half of Lake Superior, so as a result there could be some additional minor snow accumulations. && .AVIATION...(For the 06Z TAFS through 06Z Tuesday night) Issued at 1255 AM EST TUE NOV 15 2016 A shallow moist lyr/weak llvl ne slowly veering toward the s flow wl result in plenty of lo clds early this mrng. The best chc for the more persistent lower IFR cigs wl be at SAW, where the llvl flow direction wl present a greater upslope component. As the flow veers further toward the ssw on Tue mrng ahead of an aprchg lo pres trof, expect improving conditions to VFR at SAW and IWD, where this flow wl downslope. Best chc for the more persistent MVFR conditions wl be at CMX, the location farthest to the n where the longer upglide/waa wl improve the chances for deeper saturation. A wshft to the w behind a passing lo pres trof and upslope wind component wl maintain the MVFR cigs at CMX while SAW and IWD remain VFR. && .MARINE...(For the 4 PM Lake Superior forecast issuance) Issued at 253 PM EST MON NOV 14 2016 Northeast winds to around 20 knots will diminish tonight to less than 10 knots as a ridge builds into the area. Northwest winds may increase to 30 knots by Tuesday night behind a trough moving through the region. The next chance for gales, especially over the wrn lake, is expected by late Thursday night into Friday as northeast winds increase in response to a deep low pressure system approaching from the plains. While uncertainty remains with the track of that low...there could be some high end north to northwesterly gales or even storm force winds Saturday into Sunday as the low exits the Upper Great Lakes. && .MQT WATCHES/WARNINGS/ADVISORIES... Upper Michigan... None. Lake Superior... None. Lake Michigan... None. && $$ SHORT TERM...JLB LONG TERM...Voss AVIATION...KC MARINE...MZ
Area Forecast Discussion
National Weather Service San Francisco Bay Area
1012 PM PST Mon Nov 14 2016 .SYNOPSIS...Low clouds and patchy dense fog along the coast and near the Bays will move back into the valleys during the evening and overnight hours. The tail end of a weakening cold front moving into northern California overnight will likely bring some light rain to portions of the North Bay Tuesday morning, and rain chances elsewhere through the day. Unsettled weather with continuing shower chances will persist through Wednesday. Dry and seasonable weather returns Thursday and Friday, but with cooler overnight lows. More significant and widespread rainfall appears on tap for the weekend. && .DISCUSSION...As of 8:55 PM PST Monday...Fog and low clouds were slow to clear from around San Francisco Bay today. As a result, high temperatures near the Bay were as much as 9 degrees cooler than temps over the weekend. Cooling also occurred near the ocean. Inland areas remained relatively warm. Evening satellite and surface observations shows that areas of low clouds and fog continue, mainly across coastal areas south of San Francisco and into the Salinas Valley. Surface dewpoints this evening are similar to last evening, so it`s likely that fog will become more widespread overnight, with patchy dense fog once again possible from late tonight into Tuesday morning. An upper trough currently located off the coast of the Pacific Northwest is moving slowly to the east-southeast this evening. An associated cold front will move into northwest California overnight and will likely spread light rain into the northern portion of our forecast area late tonight and Tuesday morning. The frontal boundary is forecast to rapidly weaken as it pushes into our region on Tuesday morning. In fact, the latest HRRR model shows rain developing only across coastal section of Sonoma and Marin Counties through late Tuesday morning. The 00Z WRF is similar, although earlier runs of the WRF showed light rain reaching as far south as northwest Monterey County by early Tuesday afternoon. In any case, the general idea here is that rainfall amounts on Tuesday are expected to be very light (generally less than a tenth of an inch) and mostly confined to coastal areas. The cool upper trough following the dissipating cold front is set to track across northern California late Tuesday Night and Wednesday. The model consensus now is for very little precipitation with the upper trough, perhaps just a few isolated showers. The trough will spread a much cooler airmass across our region by midweek. Some of the wind protected inland valleys may see patchy frost by Thursday morning and again on Friday morning. From previous discussion...Rain chances return for the weekend with longer range models in good agreement in renewed, and stronger, upper level trough development along the West Coast. Details vary significantly between solutions however, with the 18Z GFS showing rainfall totals of 1.5 to 4.25 inches by Monday morning (which would locally mean quite a bit more given the limited topographic resolution of the available model output) -- but in contrast the latest run of the Canadian model less than an inch across most of our area, with the ECMWF solution intermediate between the two. Similar variations exist in the timing. && .AVIATION...As of 9:50 PM PST Monday...For the 06Z TAFS...Low clouds filling in quickly around the southern half of the San Francisco Bay and down the Santa Clara Valley which will soon affect area terminals. Low clouds and fog also prevail around the Monterey Bay Area and down the Salinas valley. Confidence remains low as to how widespread the fog will be but the boundary layer remains very moist and shallow dense fog is likely over Bay Area valleys. Low confidence. Vicinity of KSFO...Low clouds are expected to fill in overnight with localized dense fog possible due to the abundance of low level moisture. Confidence is low as to how long lived or widespread the fog will be. Cigs anticipated to lift between 18z- 21z Tuesday morning. SFO Bridge Approach...Similar to KSFO. Monterey Bay Terminals...LIFR cigs prevail across Monterey Bay area terminals with a gradual decline in vsbys expected through tonight. Ceiling anticipated to lift between 17z-20z Tuesday morning. Low confidence. && .MARINE...as of 9:00 PM PST Monday...Areas of fog expected along the coast tonight mainly south of the golden gate. A cold front will move through the waters Tuesday with increasing NW winds by the afternoon and evening. Behind the front a large NW swell will impact the area through midweek. && .MTR WATCHES/WARNINGS/ADVISORIES... .Tngt...SCA...Pt Pinos to Pt Piedras Blancas 0-10 nm && $$ PUBLIC FORECAST: Dykema/Blier AVIATION/MARINE: CW 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
National Weather Service Albany NY
919 AM EST Tue Nov 15 2016 .SYNOPSIS... As a weak storm moves up the coast into New England, periods of light rain are expected during the day on today, especially for areas east of the Hudson Valley. With the clouds and expected rainfall, temperatures will be cooler than recent days. Behind this storm, temperatures will return to being above normal for the remainder of the week, with mainly dry weather. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... As of 900 AM EST...Leading edge of the rain was advancing northwestward through the Mid Hudson Valley, Catskills, Northwest Connecticut and quickly approaching I90 corridor. Surface low was just south of Long Island as latest IR Satellite imagery reveals quickly cooling cloud tops in the vicinity of NYC. Several lightning strikes are also noted as the rain shield is expanding. Per the latest RAP13/HRRR, seems some adjustments to the PoP/Wx grids are in order as we will increase both in time and coverage the rainfall through most of eastern NY into western New England. Seems the TROWAL and Deformation zone will line up over most of eastern NY as we will need to watch for convective trends into western New England where recent hourly RAP updates continue to drop the Showalter Index values below zero. If these trends become more apparent, we will introduce thunder to the grids with the next update. As for rainfall amounts, also increased those values further westward. Temperatures today will be cooler than recent days with highs generally in the 40s. A few spots (such as in northwestern parts of the area) may see highs around 50. && .SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/... Steady rainfall in the evening will taper off to showers by late this evening into tonight as the low pressure area continues to lifts towards northern New England. Still, the upper level trough overhead and cyclonic flow in place could allow for a few additional rain showers, especially for northern and eastern parts of the area. It will remain cloudy overnight, as low-level moisture will be trapped beneath an inversion. Lows will only be in the mid to upper 30s. With the upper trough still overhead, there will be more clouds than sun for Wednesday, although some breaks will occur from time to time for valley areas. There could be a few additional light rain showers or sprinkles across western areas thanks to the passing upper level trough, but it should be dry for most of the day. Highs will be milder once again, with temperatures reaching into the 50s for valley areas. As the upper level through starts to slide eastward, strong upper level ridging will build into the area for the remainder of the work week, as a large area of surface high pressure dominates much of the eastern US. This will allow for dry weather with clearing skies for Wed night through Thursday Night. Temps aloft will be warming, allowing for above-normal daytime highs. Overnight lows on Wed/Thurs nights will generally be in the 30s and highs on Thursday look to reach the upper 40s to upper 50s across the area. Most spots will see highs of 5 to 10 degrees above normal. && .LONG TERM /FRIDAY THROUGH MONDAY/... Guidance is in agreement that the longwave pattern will be amplified across the CONUS through the period. A strong low pressure system is expected to have formed over the Plains and is forecast to be moving into the Great Lakes region as we close out the week and head into the weekend. It`s expected that high pressure across our region will be weakening as we are squeezed between the system moving across the Great Lakes and a storm located around 500 miles east of Montauk Point resulting in fair and mild weather; highs in the 50s and lows in 30s. It appears the Great Lakes system should occluded as its cold front moves eastward across the Northeast Saturday night into Sunday with showers, mainly rain, expected across the area. The uncertainty in the forecast grows as the upper trough is expected to become negatively tilted with an low developing over the region by late in the weekend and how it interacts with the offshore storm. The indications are the coastal storm will be drawn westward and will consolidated into a low over New England which should lift northward through early in the week. This set up will have cyclonic flow across the region drawing colder air across the relatively warm water of the Great Lakes resulting in lake enhanced rain/snow showers. Temperatures are anticipated to run below normal as we head into Thanksgiving weekend with highs only in upper 20s to lower 40s Monday along with brisk and gusty winds. && .AVIATION /14Z TUESDAY THROUGH SATURDAY/... An area of low pressure located off the Delmarva continues to head northward. Pressure falls are occurring just to its north south of Long Island. Clouds will continue to thickening and lowering this morning as rain overspreads TAF sites during the day with conditions lower to MVFR during the morning at KPOU, by afternoon at KPSF, in the early afternoon at KALB and by late afternoon at KGFL. The steadiest rainfall is expected this afternoon into the evening as the low moves into New England. A period of IFR conditions are expected at KPOU and KPSF. The rain is expected to end from southwest to northeast during the evening hours into the overnight with MVFR conditions lingering with IFR at KPSF. A light north to northeast flow will develop this morning and continuing through much of the day with the winds diminishing in the evening. Outlook... Wednesday Night: No Operational Impact. NO SIG WX. Thursday: No Operational Impact. NO SIG WX. Thursday Night: No Operational Impact. NO SIG WX. Friday: No Operational Impact. NO SIG WX. Friday Night: No Operational Impact. NO SIG WX. Saturday: No Operational Impact. NO SIG WX. Saturday Night: Moderate Operational Impact. Chance of SHRA. Sunday: Moderate Operational Impact. Chance of SHRA. && .FIRE WEATHER... As a weak storm moves up the coast and into New England, a wetting rainfall is expected for many areas, especially east of the Hudson Valley. With clouds and rain today, RH values will only be as low as 55 to 75 percent, mainly for this morning before rain picks up in coverage/intensity. North to northeast winds will be 5 to 10 MPH. RH values will stay elevated tonight with light winds. On Wednesday, clouds will break for some sunshine, mainly for valley areas. RH values will fall to 50 to 65 percent in the afternoon with west winds of 5 to 10 MPH. && .HYDROLOGY... A storm system moving up the coast to the east of the region will bring some rain today into this evening, especially between the late morning and afternoon hours. Most areas will see between a quarter to half inch of rain, although the western Adirondacks may see slightly lower amounts. A few spots in western New England may see up to an inch of rain thanks to some locally heavier downpours. This rainfall is much needed due to the recent very dry conditions. Some smaller rivers/streams may have very minor rises, but for the most part, flows will hold steady following this much needed rainfall. Although a stray lingering shower can`t be ruled out for western areas on Wednesday, dry weather will return for Wednesday night through Saturday. Another chance of rain will arrive with another frontal boundary for Saturday night into Sunday. The US Drought Monitor continues to have much of the area in the D1 (Moderate Drought) to D2 (Severe Drought) categories. This rainfall is helpful, but probably not enough to significantly change these classifications this week. For details on specific area rivers and lakes, including observed and forecast river stages and lake elevations, please visit the Advanced Hydrologic Prediction Service /AHPS/ graphs on our website. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. MA...None. VT...None. && $$ SYNOPSIS...Frugis NEAR TERM...Frugis/BGM SHORT TERM...Frugis LONG TERM...IAA AVIATION...IAA FIRE WEATHER...Frugis HYDROLOGY...Frugis
Area Forecast Discussion
National Weather Service Bismarck ND
1000 AM CST Tue Nov 15 2016 .UPDATE... Issued at 958 AM CST Tue Nov 15 2016 The forecast was updated with the latest observations. No major changes were made. UPDATE Issued at 555 AM CST Tue Nov 15 2016 Quick update to increase cloud cover this morning per IR satellite trends through 11 UTC. && .SHORT TERM...(Today and tonight) Issued at 334 AM CST Tue Nov 15 2016 Quiet and mild weather continues today and tonight under the influence of broad 500-mb ridging across the northern Plains. Early day moisture channel (water vapor) imagery shows a short wave trough moving through central Manitoba, and 00 UTC upper- air analyses revealed an intense 150 kt 300 mb jet core on the equatorward side of that wave from Seattle, WA to Glasgow, MT. Forcing in the left-exit region of that jet streak drove high- based shower activity in our area overnight, but that maximum in high-level winds is forecast to weaken by daybreak. Radar trends and HRRR simulations concurrently suggest the lingering shower activity in east central ND will exit the area before 12 UTC as a weak cold front also completes its passage through the area. For today, we expect clearing skies thanks to subsidence tied to weak height rises aloft and surface high pressure, which will be in firm control today as it slowly crosses the area. Mixing may be somewhat limited under the surface high, so temperatures are more apt to fall in line with the 00 UTC multi-model consensus than on previous days. We nonetheless tipped our hats slightly in favor of warmer MOS guidance in respect to the sunshine, snow- free ground and drying soils, and recent model biases related to the latter conditions. Forecast highs thus range from the upper 40s F along the Canadian border to the upper 50s along the ND-SD state line. Tonight, a relatively rapid temperature fall is likely to occur this evening even though the 00 UTC model consensus places the surface high over the eastern Dakotas by that time. Low-level drying today beneath the high and dry soils will likely favor a temperature fall that`s greater than the model consensus, which we have experienced several times in the last week. We therefore relied on the cooler edge of the 00 UTC model guidance set to build tonight`s temperature forecast, which calls for lows from the upper 20s to lower 30s F. That being said, cloud cover will likely increase through the night and combined with a ramp-up in warm air advection, there is some uncertainty in our move to use some of the colder guidance for the forecast. Finally, low PoPs are being carried in the north tonight where the mid-level warm air advection will be focused. .LONG TERM...(Wednesday through Monday) Issued at 334 AM CST Tue Nov 15 2016 All eyes remain on the possible late-week storm system which we have been advertising with a cautious tone the last several days due to the large degree of uncertainty in the details associated with its evolution. However, our confidence is slowly growing as the late week period moves inside the initial-condition-dominated predictability horizon of model guidance. More to the point, our confidence is slowly increasing that the heaviest snowfall and strongest winds with the late-week system may end up south and east of most of western and central ND. Looking back at the last 24 hours of global model guidance, it appears there`s a convergence toward a more common solution with regard to the timing and path of the 700 to 500 mb lows that have been forecast to develop on the High Plains Thursday night and then eject northeast to the western Great Lakes by Friday night. The 00 UTC GFS made a significant shift south and eastward with those lows, taking the 500 mb circulation from Norfolk, Neb at 12 UTC Friday to Eau Claire, WI by Friday evening. The 00 UTC ECMWF remained the fastest model simulation (and indeed is a fast out- lier compared to the 12 UTC ECMWF ensemble members), but its mid- and upper-level low tracks were relatively similar to the GFS, if only a touch further southeast. There was also a significant shift in the 00 UTC GFS ensemble members at points over western and most of central ND toward a drier scenario, also suggesting that model guidance is beginning to "lock in" to a common idea that may well be an accurate one. As an example of that shift, at Bismarck, the 12 UTC GFS ensemble mean event-total QPF was around 0.60 inches, but only one member of the 00 UTC GFS ensemble pack produced that much QPF. The GFS ensemble mean at Bismarck is now only near 0.15 inches. Assuming an average 13 to 1 snow-to-liquid ratio, which is reasonable since forecast thermal profiles with this system have never been simulated to be cold enough for more than a small layer in the favored dendritic growth zone, that means the GFS ensemble mean has shifted from a potential 8 inch snowfall to a potential 2 inch snowfall at Bismarck as that particular ensemble system`s most probable scenario. Our official forecast followed the global model trends, and in fact since the simulations are also trending faster with the wave passage, we actually have a dry forecast in place during the day Friday over western and parts of central ND. The highest chance of snow will be Thursday night over most of the area per the 00 UTC multi-model consensus, It appears that the shift and convergence in model simulations is due to increasing sampling of the upper wave that was off of the Alaskan Peninsula at 00 UTC. Moreover, from the standpoint of teleconnections, recent in-house research has suggested an area of positive 500 mb height anomalies should be observed north of Alaska, but on this side of the globe, and downstream off of the coast of Newfoundland, about 5 days before a western or central ND blizzard. Currently-observed anomalies are a close, but not exact fit to those teleconnections, which also may favor a close call, but not a direct impact to the local area. Of course, we`re not ready to make a final call on this situation yet, and even the 00 UTC multi-model consensus suggests headline-worthy snowfall may impact the James River valley and perhaps south central ND, so we are still urging everyone to check back with later forecasts. Otherwise, the weather will quickly quiet down again this weekend and into early next week, though it will be much colder with lows in the teens very probable this weekend. A warming trend is then forecast to resume by early next week. && .AVIATION...(For the 12Z TAFS through 12Z Wednesday morning) Issued at 555 AM CST Tue Nov 15 2016 Isolated pockets of MVFR stratus are possible across western and central North Dakota this morning. Otherwise VFR conditions are forecast for the 12 UTC TAF cycle. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...AC SHORT TERM...CJS LONG TERM...CJS AVIATION...AYD
Area Forecast Discussion
National Weather Service Quad Cities IA IL
820 AM CST Tue Nov 15 2016 .UPDATE... Issued at 819 AM CST Tue Nov 15 2016 The dense fog appears to have reached its overnight extent. High clouds moving in overhead will delay the burn off. As a result, the dense fog advisory has been extended in time and space. An updated forecast will be available shortly. UPDATE Issued at 528 AM CST Tue Nov 15 2016 Fog has become dense across buchanan county over the past couple hours and widespread dense fog was just west of the forecast area border from Marshalltown to Ottumwa. This should expand eastward over the next couple hours under the clear skies and have thus issued a dense fog advisory until 9 am, which is matched by advisories in place over central IA and northeast IA. The thinning Ci seen on IR imagery advancing into the forecast area should allow enough sunshine to lead to at least gradual improvement by mid morning. && .SYNOPSIS... Issued at 357 AM CST Tue Nov 15 2016 At 2 am, the weak cold front that pushed through the local area Monday extended from southern Lake Michigan south across eastern IL. In its wake, there was a light NW flow and weak cold air advection pulling in a slightly cooler airmass. Satellite imagery showed a trailing axis of low clouds over WI into east central IA, while upstream, clear skies under a weak surface ridge axis over central IA into southern WI, has lead to widespread fog. This fog was beginning to develop over eastern IA, but so far the combination of the passing stratus deck and NW winds around 6 to 8 kts has kept visibilities mainly in a 3 to 5 mile range outside the quarter mile reported just north of our forecast area in Olwein. && .SHORT TERM...(Today and Tonight) ISSUED AT 357 AM CST Tue Nov 15 2016 Initial focus is on the potential for dense fog early this morning, then attention turns to temperatures. The HRRR surface visibility fields and SREF visibility probs suggest the greatest potential for dense fog this morning will be over east central IA, mainly northwest of a line from roughly Sigourney to Monticello around 4 am to 9 am. Conceptually, this makes sense as this area will be closest to the approaching ridge and associated weakening wind fields and radiational cooling under the pocket of clear skies. Have added patchy fog for now and issued a special weather statement patchy dense fog through the morning commute. Will continue to monitor for the need for an advisory early this morning. Satellite imagery shows an area of dissipating high clouds topping the upper ridge axis from the northern plains into NW IA rapidly spreading E-SE. This may hamper the on-going radiational cooling and makes the fog forecast more challenging. Later today, the ridge axis slides overhead, providing light winds and mostly sunny skies. Highs will be only slightly lower than Monday as the initially cooler airmass will be offset by a light southerly return flow by afternoon. Tonight, another weak, dry front pushes through in the evening with the ridge axis building back overhead by morning. Fog is again suggested by the SREF under the eastern side of the ridge axis over NW IL and have added patchy fog wording toward sunrise. Much like tonight, will see mins from the mid 30s to lower 40s under the mostly clear skies. .LONG TERM...(Wednesday through Monday) ISSUED AT 357 AM CST Tue Nov 15 2016 Overview: After near record highs on Thursday, a pattern change to cooler weather is likely by this weekend continuing into next week. Wednesday and Thursday: Very warm for the middle of November in the 60s on Wednesday, then upper 60s to mid 70s on Thursday (see Climate Section for the daily records). Suite of models have a 995-1000mb sfc low tracking through western or central Iowa on Thursday. Regardless of the exact strength and track, E Iowa/NW Illinois will be in the warm sector of this system with 850mb temps surging into the 14-18 C range or 2 standard deviations above the mean. Consequently, it`s going to be breezy - southerly winds sustained 20-25 mph with gusts of 30-35 mph. The highest winds are forecast along and south of I-80. Friday and Saturday: Most significant weather impacts will be the strong winds, and the much cooler temps by Friday night/Saturday. Forecast highs on Saturday are in the lower 40s south to upper 30s north. Precipitation: The sfc low is forecast to move into NW Wisconsin on Friday bringing heavy precip to parts of Minnesota and Wisconsin; however, significant precipitation is not expected for E Iowa/NW Illinois because the low- level jet is veered to the WSW causing less than optimal WV transport along the cold front. The eastern CWA stands the best chance for showers and isolated storms Friday morning into the early afternoon before a mature dry-slot punches into the region from the SW as it wraps into the center of the low. On the backside of the low, wrap around snow showers or flurries are likely, especially across the NE half of the area with the Quad Cities on the edge. No accumulation is expected at this time. Winds: WSW winds during the day Friday will veer to westerly overnight. For now, trended SuperBlend toward raw model consensus which yields 20-25 mph sustained winds and gusts of 30-35 mph with potential for occasionally gusts near 40 mph. On Saturday, as the sfc low reaches the Northern Great lakes, a strong pressure gradient will reside to the W/SW. Cold air advection/isentropic downglide should foster deep dry adiabatic profiles extending from the sfc to above 850mb. There is some model uncertainty at this lead time, but based on a conceptual model appropriate to this synoptic setup, potential is there for gusts over 40 mph, especially late Friday night into Saturday afternoon. GFS forecast soundings mix up into 50 kt winds, something to monitor through this week. Sunday through Tuesday: Below average temps in the 30s and 40s Sunday and Monday with lows in the 20s and upper teens most areas. ECMWF/GFS differ with respect to timing and track of the next area of low pressure Tuesday of next week. ECMWF is faster and further north. Too early to say much else, except that there may be another trough in the Midwest. Uttech && .AVIATION...(For the 12Z TAFS through 12Z Wednesday Morning) ISSUED AT 530 AM CST Tue Nov 15 2016 Fog developing under a surface ridge axis in place over central IA and northeast IA continues to gradually expand east and southeast, and appears likely to impact the CID terminal with VLIFR conditions early in the forecast period. An area of IFR clouds is likely to overspread DBQ early this morning, keeping visibilities from dropping as low. MLI and BRL will have lower confidence trends, but for now appear on track to see at least a several hour period of MVFR and possible IFR conditions due to fog early this morning. By 16z, all sites should see an improvement to VFR conditions, which should prevail through the rest of the forecast period along with light surface winds. && .CLIMATE... ISSUED AT 357 AM CST Tue Nov 15 2016 Record Highs for November 17... Moline.........74 in 1941 Cedar Rapids...73 in 1941 Dubuque........71 in 1941 Burlington.....75 in 1952 && .DVN WATCHES/WARNINGS/ADVISORIES... IA...Dense Fog Advisory until 11 AM CST this morning for Benton- Buchanan-Delaware-Dubuque-Iowa-Jefferson-Johnson-Jones- Keokuk-Linn-Washington. IL...NONE. MO...NONE. && $$ UPDATE...08 SYNOPSIS...Sheets SHORT TERM...Sheets LONG TERM...Uttech AVIATION...Sheets CLIMATE...Uttech
Area Forecast Discussion
National Weather Service Grand Forks ND
946 AM CST Tue Nov 15 2016 .UPDATE... Issued at 943 AM CST Tue Nov 15 2016 Showers have exited the area so removed pops rest of the morning. Made some minor cloud trend adjustments with remainder of the forecast ok. UPDATE Issued at 630 AM CST Tue Nov 15 2016 Adjusted POPs for current radar trends. Showers in the central and southern valley continue to push eastward as a shortwave moves through. Think a few showers will hang around in our southeastern counties until mid morning before everything pushes off to the east. && .SHORT TERM...(Today and tonight) Issued at 359 AM CST Tue Nov 15 2016 Shower chances this morning and then temperatures will be the main challenges for the period. A fairly vigorous shortwave currently moving through the Red River Valley has helped produce rain showers. The showers have been quite a bit further south than originally expected, with most of the activity spreading from the central and southern Red River Valley into west central MN. The HRRR seems to have a decent handle on current radar trends so followed it fairly closely for the early morning hours. Think that our showers should exit off to the east by 15Z or so this morning. After the shortwave moves off to the east, we should have some clearing skies later today, along with northwesterly winds picking up on the backside of the surface trough. Some cold air advection, but it is pretty weak and will be offset by sunshine. Will continue to keep highs in the upper 40s to 50s across the CWA. After some brief surface ridging this evening, winds will shift back to the south tonight ahead of the next shortwave. The winds along with increasing cloud cover will help keep temps in the 30s although the eastern tier could see a few spots in the upper 20s with lighter winds and clear skies a bit longer. .LONG TERM...(Wednesday through Monday) Issued at 359 AM CST Tue Nov 15 2016 Wednesday through Thursday...Flow will start to become more southwesterly on Wednesday as an upper ridge moves east. Weak shortwave over the top of the ridge could bring some light rain near the international border, but think that most of the precip will be in Canada. By Thursday, the large upper trough will be moving into the southern Rockies, then lifting into the central Plains Thursday night. While trends have been further south and east with the system, there is still considerable variation in how the models handle the track of the surface low. Will continue to keep high POPs and QPF over our southern counties, and with cold temperatures coming along the backside of the low on Thursday night, a changeover to snow will be likely. It will just be a question of where the heaviest band falls. Friday...Model spread still showing a wide range of possible precipitation totals across the area. The trend in the solns has shifted to the south and east as the more progressive ECMWF suite continues to lead with the Canadian and even the 06Z NAM catching on to this idea. During the day on Friday the 00z GFS operational run indicates a stronger period of snowfall with q-vector divergence lining up with frontogenetical forcing to create a stronger band of snow on the back side of the system impacting west central MN and the far eastern zones of the FA. As a result the spread of solns across the east remains very large, leading to low confidence in totals. Wheres the spread in the northern valley and DVL basin has reduced, increasing confidence for less impactful event. Saturday to Monday will see an overall dry period as 500mb flow transitions from the aforementioned storm system/trough to ridging by Sunday. Another short wave will bring weak PoPs to the area Monday with highs generally in the 30s and lows in the teens and 20s, which is quite normal for the third weekend of November. && .AVIATION...(For the 12Z TAFS through 12Z Wednesday morning) Issued at 630 AM CST Tue Nov 15 2016 Have -RA mention at KFAR and VCSH at KBJI for scattered showers moving through. Rain should be done by 15Z. All TAF sites are VFR and will remain so throughout the period. The 6000-9000 ft ceilings over most of the forecast area will push eastward later this morning, leaving clear skies to a bit of cirrus. More mid level clouds will move into the northern TAF sites late in the period but ceilings will be fairly high. Winds will shift to the northwest and have some gusts above 20 kts this afternoon, but then become light and variable by the end of the period. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...None. MN...None. && $$ UPDATE...Voelker SHORT TERM...JR LONG TERM...JR/JK AVIATION...JR
Area Forecast Discussion
National Weather Service Marquette MI
645 AM EST Tue Nov 15 2016 .SHORT TERM...(Today and tonight) Issued at 503 AM EST TUE NOV 15 2016 WV imagery and RAP analysis indicated a mid/upper level ridge from the sw CONUS into the wrn plains resulting in wnw flo from srn Canada to the nrn Great Lakes. An upstream shortwave trough extending from srn Manitoba into ern North Dakota supported areas of light rain from nw Ontario into nw MN. At the surface, a trough extended into the ern Dakotas from low pres over over nrn Manitoba. IR loop and sfc obs showed extensive low clouds over Upper Michigan as abundant low level moisture persists over the region as a weak ridge with mid level drying moves over the area. Today, although the strongest 700-300mb qvector conv with the shortwave moving into the region will remain to the north of the cwa, expect that it will be strong enough to support sct showers into the west by late morning and through cntrl Upper Michigan during the afternoon. However, rainfall amounts will be light, generally less than a tenth of an inch. With weak WAA into the afternoon, max temps will remain above normal with highs around 50. Tonight, expect the showers over the east half of the cwa in the evening to move out between 03z-06z. With partial clearing late over the west, temps could drop to near 30. Otherwise, the clouds will keep min readings generally in the mid 30s to around 40. .LONG TERM...(Wednesday through Monday) Issued at 346 AM EST TUE NOV 15 2016 A zonal Pacific airflow wl continue the relatively warm and mainly dry wx for Wed into Thu. But later in the week the pattern is expected to amplify, as a stronger disturbance/low pres system lifts ne from the Four Corners region and brings in some pcpn on Fri and likely some accumulating lake effect snow in its wake next weekend. Wed/Thu...Large scale ridging/subsidence in the wake of Tuesday`s departing shortwave wl bring a drying trend by Wed. As the sfc ridge axis shifts to the e on Wed and the wind shifts to the sw, increasing waa clouds are expected later Wed into Thu but dry conditions will persist. Unseasonably warm Pacific air wl continue to dominate during this time with h85 temps rising as high as 6-8C Wed night into Thu. Fri into Sun...Longer range models continue to display some variability on the track...timing and intensity of the shortwave/sfc low pres emerging from the Four Corners region of the CONUS and tracking ne thru the Plains and toward the western Great Lakes. The GFS model after showing good run-to-run continuity on a slower solution the past several days has now trended 6-12 hours quicker on its 00z run taking the sfc low through western Upper Mi Fri evening/early overnight and then into central Upper Mi by 12z Sat. The 00z GFS still remains about 12 hours slower than the 12z ECMWF run, but both indicate a similar storm track. The Canadian model run has also trended farther west on its 00z run and shows a similar track/timing than the 00z GFS although it is slightly farther east. Given that the models appear to be converging on a similar track, forecast confidence increases although timing of system remains in question, and will affect timing changeover from rain to snow. Given quicker timing trend of the 00z GFS would expect the bulk of synoptic pcpn to be mostly in form of rain for our area late Thu night into Fri evening, but then expect a quicker transition to lake enhanced/lake effect snow for late Fri night in the far west and across the rest of the cwa Sat morning into early afternoon as instability increases dramatically with h85 temps dropping as cold as -15c by late Sat night into Sunday. Several inches of lake effect snow accumulation in the northwest wind snow belts of Lake Superior certainly looks possible from late Fri night into Sunday morning before the snow tapers off from west to east on Sun with weakening cyclonic northerly flow and increasing ridging/subsidence from the north and west. Would not be surprised if some counties in nw snowbelts push advisory criteria snowfall of 4 or more inches in a 12 hour period. Heaviest snow looks like it would occur from late Fri night into Sat for the western counties and Sat into early Sunday for the rest of the cwa. Along with the potential for the first widespread accumulating snow of the season, the other big part of the story with this storm system will be the wind and cold. With the influx of cold air beginning in the far west late Fri night and spreading east on Sat, the corresponding increase in instability will also increase mixing to allow for strong and gusty nw winds to develop. GFS soundings indicate the potential for a period of storm force winds over the east half and north central portions of Lake Superior from mainly Sat afternoon through Sat evening. High wind warning criteria gusts to near 60 mph would also be possible from over the tip of the Keweenaw Peninsula to Lake Superior shoreline areas east of Marquette over roughly the same time period. A period of wind advisory gusts of 45 to 50 mph seem a good bet across much of the rest of the cwa from Sat into Sat evening. The combination of the snow, falling temps and strong winds will be a rude awakening after the above normal fall temps experienced thus far, and headlines will likely be needed across much of the region. Also expect wind chills to plummet through the teens over the west half Sat afternoon and across the entire U.P. on Sat night. Sun night into Mon...Lake effect snow and nw winds will continue to slowly diminish through this period as gradient slackens on backside of departed storm system and sfc ridge axis continues to move in from the west. Lake effect snow will hang on longer over the east half of the cwa due to slower diminishment of nw winds and longer fetch across the eastern half of Lake Superior, so as a result there could be some additional minor snow accumulations. && .AVIATION...(For the 12Z TAFS through 12Z Wednesday morning) Issued at 645 AM EST TUE NOV 15 2016 Expect mainly MVFR conditions through today as low level moisture persists over the area. A wshft to the w behind a passing lo will bring drier air into the region with conditions lifting to VFR late today at IWD and tonight at CMX and SAW. && .MARINE...(For the 4 AM Lake Superior forecast issuance) Issued at 510 AM EST TUE NOV 15 2016 Southwest winds to 25 knots today will veer to nw tonight behind a trough moving through the region. The next chance for gales, especially over the wrn lake, is expected by late Thursday night into Friday as northeast winds increase in response to a deep low pressure system approaching from the plains. While uncertainty remains with the track of that low...there could be some high end north to northwesterly gales or even storm force winds Saturday into Sunday as the low exits the Upper Great Lakes. && .MQT WATCHES/WARNINGS/ADVISORIES... Upper Michigan... None. Lake Superior... None. Lake Michigan... None. && $$ SHORT TERM...JLB LONG TERM...Voss AVIATION...JLB MARINE...JLB
Area Forecast Discussion
National Weather Service Raleigh NC
1032 AM EST Tue Nov 15 2016 .SYNOPSIS... Cyclonic flow aloft will prevail over the Carolinas today, in association with a broad upper level trough over the eastern United States. Northwest flow aloft will develop late tonight and Wednesday as an amplified upper level ridge over the Rockies expands east across the Central Plains toward the Mississippi river valley. && .NEAR TERM /THROUGH TONIGHT/... As of 1030 AM Tuesday... Morning update... Fog and stratus over the coastal plain and southern Piedmont areas are slowly eroding (more aggressively in the coastal plain), though RAP soundings suggest a period of low strato cu may develop as heating increases this morning. The overall atmosphere is very dry and RH fields show all areas being cloud free this afternoon, though some cirrus is possible given several small amplitude shortwave rotating through the larger scale trough aloft. The 1342m low-level thickness at GSO this morning supports the mid 60s high temp forecast, so changes to highs will be minor. Otherwise, no further changes are needed. -BS Previous discussion A broad upper level trough centered invof the southern Appalachians this morning will amplify as it shifts toward the Southeast coast today/tonight, in response to potent shortwave energy (as evidenced by the presence of nocturnal convection in MS/TN at 08Z) digging SE from the central MS river valley into the Deep South and NE GOMEX. On the eastern periphery of the aforementioned trough, potent shortwave energy lifting slowly N/NE toward the DELMARVA this morning (same energy that tracked through central NC yesterday) will continue to make slow progress along the Mid-Atlantic coast this afternoon into tonight. Subsidence in the wake of the aforementioned wave, along with the advection of a drier low-level airmass into central NC via relatively weak (10-15 kt) SFC-925 mb flow is expected to result in clearing skies today, with highs in the 60s. Expect clear skies with lows in the mid/upper 30s to lower 40s tonight, warmest in the SE Coastal Plain. -Vincent && .SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/... As of 315 AM Tuesday... Shortwave trough digging into the Western US will result in downstream amplification of the Central US ridge as it builds east into the region. At the surface, high pressure centered over the Lower Ms Valley/Northern Gulf Coast States will shift east over the area. This will spell mild and dry weather conditions for the state. Highs in the mid 60s north to around 70 south. Overnight lows in the upper 30s to lower 40s. && .LONG TERM /THURSDAY THROUGH MONDAY/... As of 315 AM Tuesday... The high-amplitude shortwave ridge over the East Coast will shift offshore early Saturday in advance of a deepening shortwave trough and attendant strong cold front emerging out of the nation mid- section. Expect very warm temperatures ahead of this formidable system, with highs Friday in the lower to mid 70s, and possibly again on Saturday if the slower timing of the GFS verifies. Despite the magnitude of this system, the late departure of the ridge axis over the area will limit appreciable moisture recovery and thus limit precip chances with only a narrow band of showers expected to accompany the cold frontal passage during the day on Saturday. The coldest air of the season is forecast to spill south into the area on Sunday and lingering into early next week, underneath an anomalously deep vortex over the Mid-Atlantic States/Northeast. Highs Sunday and Monday could struggle to reach into the 50s across northern portions of the piedmont and coastal plain. Highs 50 to 55. Lows in the mid 20s to lower 30s. && .AVIATION /15Z TUESDAY THROUGH SATURDAY/... As of 715 AM Tuesday... 24-hr TAF Period: Low stratus/fog affecting portions of central NC early this morning are expected to dissipate between 13-15Z in assoc/w the advection of a drier airmass into central NC from the W/NW. After ~15Z, VFR conditions will prevail at all terminals through the remainder of the TAF period, with a NW breeze at 7-12 kt this afternoon becoming calm or light/variable tonight. Looking Ahead: VFR conditions will rule tonight through the remainder of the week in assoc/w an upper level ridge building over the region from the west. -Vincent && .RAH WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...VINCENT NEAR TERM...SMITH SHORT TERM...VINCENT LONG TERM...CBL AVIATION...VINCENT
Area Forecast Discussion
National Weather Service Wakefield VA
357 PM EST Tue Nov 15 2016 .SYNOPSIS... High pressure builds over the Southeast states tonight. A weak trough of low pressure pushes through the Mid Atlantic and Northeast states on Wednesday...with high pressure then building over the local area Thursday and Friday. A strong cold front pushes across the region Saturday. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... Latest GOES water vapor imagery depicts a broad upper level trough over the Mid-Atlantic region. The upper level energy that brought rain to the region yesterday is slowly lifting along the Northeast coast. The associated surface low is centered just offshore of New Jersey. A couple of vorticity maxima over the region indicated in the RAP is resulting in some stubborn mid level clouds over the region. The added cloud cover and northwest winds have kept temperatures in check. Expect cloud cover to erode/dissipate late today as a slightly drier air mass advects from the northwest and the low level lapse rates decrease. Northwest winds decouple tonight, allowing for great radiational cooling. Expect some patchy fog to develop across south central Virginia into central Virginia to the Piedmont late tonight. Lows drop into the mid to upper 30`s inland to low to mid 40`s near the coast. Some patchy frost is possible inland, where temperatures will drop into the mid 30`s. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY/... Northern stream disturbance digs into the Mid-Atlantic region Wednesday morning, with an associated weak cold front/wind shift pushing through the local area Wednesday afternoon/evening. Height falls are minimal ahead of the sheared vorticity lobe Wednesday. Omega fields also indicate limited forcing for ascent. Moisture will also be a limiting factor with precipitable waters progged around one half to three quarters of an inch. Dynamics will likely not be sufficient to overcome the limited moisture and dry sub- cloud layer. Have retained silent POPs. Expect an increase in mid level clouds across the northeast, with the sky averaging mostly sunny southwest to partly cloudy/mostly cloudy northeast. Highs generally in the low to mid 60`s. Shortwave pushes offshore late Wednesday night as the front weakens/dissipates. A clearing sky is expected, with lows generally in the upper 30`s to low 40`s inland to mid to upper 40`s near the coast. Heights build Thursday as an anomalous upper ridge builds over the eastern US. Large scale confluence behind the departing trough pulls surface high pressure into the region. 850Mb temperatures warm to +10 to +12C (approaching +1 standard deviation) late Thursday, but a subsidence inversion around 900-875mb Thursday afternoon and northwest winds will help keep temperatures in check. Highs forecast in the low to mid 60`s east to mid to upper 60`s west under a sunny sky. Clear Thursday night with lows in the upper 30`s to low 40`s. The ridge axis locates over the Mid- Atlantic region Friday as high pressure centers along the Southeast coast. Return flow late Friday and 850mb temps warming to +12 C per latest GEFS will push daytime temperatures into the low 70`s inland (+1 standard deviation) and mid to upper 60`s neat the coast. Dry conditions prevail under a sunny sky. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... High pressure ridge Friday evening will shift to the east of the area by Saturday morning. A digging upper level trough will sweep onto the Eastern Seaboard Saturday afternoon bringing a strong cold front from across the area. Scattered showers are possible beginning in the northwest Saturday afternoon and moving to the east Saturday night and Sunday. Highest POPs are northern portions with 30 percent POPS except up to 40 percent in the northeast Saturday night into Sunday morning...diminishing Sunday afternoon. Dry weather returns Sunday night through Tuesday as strong high pressure builds in from the west. Mild Saturday with highs 65 to 70 except low 60s on the Lower Eastern Shore. Much cooler Sunday and Monday with highs within a few degrees of 50 degrees. Slightly warmer Tuesday with maximums of 50 to 55. Lows 40 to 45 Saturday morning 35 to 40 Sunday morning and upper 20s to mid 30s Monday and Tuesday mornings. && .AVIATION /21Z TUESDAY THROUGH SUNDAY/... Low pressure south of Long Island will move northeast into New England tonight and Wednesday. A weak cold front will cross the region Wednesday night. High pressure builds into the area Thursday and Friday. A strong cold front moves through the Mid Atlantic States Saturday. Patches of stratus were over much of eastern Virginia this morning and were dissipating toward midday. Some scattered 25 hundred layers may affect some TAF sites into mid afternoon. A clear sky will prevail late this afternoon and tonight. Some hires models indicate fog development across south central Virginia Wednesday morning. This is reasonable given the recent rainfall and expected near calm winds. Included MVFR at RIC around sunrise. Widespread IFR is not indicated at this time. Any fog burns off quickly Wednesday morning with a mainly clear sky and light winds expected. OUTLOOK...A weak cold front or surface boundary Wednesday night will be dry. VFR and dry conditions continue through Friday. There will be a chance for showers late Saturday or Saturday night. More dry weather returns Sunday but with MVFR ceilings possible. && .MARINE... Winds/waves continue to diminish as the low pressure off the New Jersey coast moves NE and away from the area. A weak ridge of high pressure builds across the area on Wednesday ahead of a weakening cold front/trough moving through the area Wed evening. No weather will be associated with this front. However, northwest winds behind it will increase as a stronger ridge of high pressure builds in for Thursday. The high centers itself over the middle Atlantic for Fri into Saturday Morning before a strong cold front moves through Saturday afternoon and night. Will need to watch for NW gale force gusts possibly Saturday night into Sunday behind this front. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...None. NC...None. VA...None. MARINE...None. && $$ SYNOPSIS...LKB NEAR TERM...LKB/SAM SHORT TERM...LKB/SAM LONG TERM...LSA AVIATION...LSA MARINE...MRD
Area Forecast Discussion
National Weather Service Albany NY
436 PM EST Tue Nov 15 2016 .SYNOPSIS... Low pressure will move from south of Long Island this evening to north of Boston, Massachusetts tonight, bringing periods of rain to the area. Skies should gradually clear on Wednesday. Fair and mild conditions are forecast Thursday into Saturday. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... As of 435 PM EST...areas of rainfall continue across all of the forecast area except far northern Herkimer and Hamilton Counties. Radar shows the precipitation moving towards the north or northwest. Temperatures are generally in the 40s except lower 50s in the southern Adirondacks where there was some sunshine earlier today. Latest RAP analysis shows low pressure responsible for the rain near the southern shore of Long Island. && .SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/... Steady rainfall in the evening will taper off to showers by late this evening into tonight as the low pressure area continues to lifts towards eastern New England. Still, the upper level trough overhead and cyclonic flow in place could allow for a few additional rain showers, especially for northern and eastern parts of the area. It will remain cloudy overnight, as low-level moisture will be trapped beneath an inversion. Lows will only be in the mid to upper 30s. With the upper trough still overhead, there will be more clouds than sun for Wednesday, although some breaks will occur from time to time for valley areas. There could be a few additional light rain showers or sprinkles across western areas thanks to the passing upper level trough, but it should be dry for most of the day. Highs will be milder once again, with temperatures reaching into the 50s for valley areas. As the upper level through starts to slide eastward, strong upper level ridging will build into the area for the remainder of the work week, as a large area of surface high pressure dominates much of the eastern US. This will allow for dry weather with clearing skies for Wed night through Thursday Night. Temps aloft will be warming, allowing for above-normal daytime highs. Overnight lows on Wed/Thurs nights will generally be in the 30s and highs on Thursday look to reach the upper 40s to upper 50s across the area. Most spots will see highs of 5 to 10 degrees above normal. && .LONG TERM /FRIDAY THROUGH TUESDAY/... A strong ridge of high pressure at both the surface and aloft will bring fair and mild weather to the area Friday into Saturday. Lows generally in the 30s with highs mainly in the 50s. With a very dry atmospheric column, the lows both mornings could be 5-7 degrees colder than forecast with light winds and clear skies. Uncertainty in the forecast grows as an upper trough is expected to approach and become negatively tilted (12Z GFS) or cut off south of the area (12Z Euro). GFS solution would bring a period of rain followed by colder air and lake effect snows as colder air get pulled in from Canada. Euro solution would imply a significant snow storm for at least the northwest part of our forecast area. GFS solution is also faster and would have some precipitation reaching our area by later Saturday. WPC probabilistic guidance has a 30-50 percent chance of accumulating snow Sunday into Monday across the western part of the forecast area. For now, just put a statement in our HWO for entire area mentioning the possibility of accumulating snow Sunday into Monday. Lows on sunday in the 30s with highs in the 30s and 40s. Lows on Monday from the Mid 20s to low 30s and highs from the upper 20s to around 40. By Tuesday, weather looks cold and brisk with northwest flow with lake effect snows in the favored areas and snow flurries possible across the rest of the area. Lows in the teens and 20s with highs in the upper 20s to around 40. && .AVIATION /21Z TUESDAY THROUGH SUNDAY/... Deepening low approaching Long Island with an expanding area of rain further west and north. This has resulted in IFR conditions impacting KPOU which should spread northward through the afternoon hours into KPSF-KALB. Late this afternoon into tonight, IFR conditions should spread into KGFL. These flight restrictions should remain in place tonight with slow improvements expected during the daylight hours Wednesday. Winds will generally be from the north at 10kts or less this afternoon into this evening. Winds should become more northwesterly tonight then westerly Wednesday morning. Outlook... Wednesday Night through Saturday: No Operational Impact. NO SIG WX. Saturday Night: Moderate Operational Impact. Chance of SHRA. Sunday: Moderate Operational Impact. Likely SHRA. && .FIRE WEATHER... Low pressure will move from south of Long Island this evening to north of Boston, Massachusetts tonight, bringing periods of rain to the area. Skies should gradually clear on Wednesday. Fair and mild conditions are forecast Thursday into Saturday. RH values will stay elevated tonight with light northerly winds. On Wednesday, clouds will break for some sunshine, mainly for valley areas. RH values will fall to 50 to 70 percent in the afternoon with west winds of 5 to 15 MPH. Winds become northwesterly and will diminish to 5 MPH or less Wednesday night as RH values recover to near 100 percent. && .HYDROLOGY... Rainfall today has ranged from zero across far northern Herkimer and Hamilton Counties to 1 to 2 inches across the eastern Catskills and Mid Hudson valley. Further north the Albany Airport has reported 0.66 inches as of 21Z. Although a stray lingering shower can`t be ruled out for western areas on Wednesday, dry weather will return for Wednesday night through Saturday. Another chance of rain will arrive with another frontal boundary for Saturday night into Sunday. The US Drought Monitor continues to have much of the area in the D1 (Moderate Drought) to D2 (Severe Drought) categories. This rainfall is helpful, but probably not enough to significantly change these classifications this week. For details on specific area rivers and lakes, including observed and forecast river stages and lake elevations, please visit the Advanced Hydrologic Prediction Service /AHPS/ graphs on our website. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. MA...None. VT...None. && $$ SYNOPSIS...SND NEAR TERM...SND SHORT TERM...Frugis LONG TERM...SND AVIATION...IAA/BGM FIRE WEATHER...SND HYDROLOGY...SND
Area Forecast Discussion
National Weather Service Peachtree City GA
311 PM EST Tue Nov 15 2016 .SHORT TERM /Tonight through Thursday/... As mentioned in previous update discussion, main concerns are fire weather forecast conditions and smoke trajectory/ concentration forecasts. Latest model guidance confirming observed trends showing mid level clouds and what little precip that is occurring dissipating quickly. Expect clear skies by late evening. Surface winds will weaken but continue from the NW and is expected to shift to more NW or NNW overnight. Flow in lowest few thousand feet overnight will be strong enough to bring smoke particulates back into Atlanta metro area and continue through much of Wednesday. Does not appear from USFS and HRRR smoke model guidance that concentrations will be as high as they were Monday but too much uncertainty to rule that out, especially if fires expand or intensify. Georgia DNR EPD has issued Code Red for tomorrow for Atlanta Metro areas, which is the only area that can have such alerts issued. Outside of these areas, our special weather statement also highlights the risk from smoke. As the surface high pushes east, surface winds will become SE Thursday. So should see a couple day break from the smoke until flow becomes NW again. Thursday will also see very warm temps with highs in the upper 70s to around 80. Does not appear daily records will be broken however. See climate section below. No significant precip expected through early next week. SNELSON .LONG TERM /Thursday Night through Tuesday/... A few tweaks were made to the long term. Winds have been increased a bit for Saturday into Sunday. New guidance showing winds stronger during that time period. Have also reduced the slight chance area for Saturday. Models continue to show a drying trend as the front moves to the south. Otherwise the forecast looks on track. 41 && .FIRE WEATHER... && .CLIMATE... Records for 11-17 Max Temperature Min Temperature Station High Low High Low ------- ---------- ---------- ---------- ---------- KAHN 84 1958 44 1951 63 1930 25 1997 1984 1943 KATL 81 1985 42 1951 63 1930 22 1997 1958 1914 1890 KCSG 84 1958 47 1951 65 1986 22 1901 1921 1916 1929 KMCN 85 1964 48 1951 65 1986 22 1901 1958 1920 1957 1914 Records for 11-18 Max Temperature Min Temperature Station High Low High Low ------- ---------- ---------- ---------- ---------- KAHN 80 1994 39 2014 63 1930 22 2014 1942 1938 KATL 80 1985 37 2014 63 1930 18 1891 2000 1928 KCSG 84 1985 42 2014 66 1986 26 2014 1951 KMCN 85 2013 42 2014 66 1986 23 2014 1957 1997 && .FIRE WEATHER... RH values got close to critical thresholds this afternoon across middle georgia. These will recover quickly. With abundant sunshine, dry conditions and light NW winds. Conditions may approach criteria Wednesday and will likely be met on Thursday when daytime humidity drops to 20 to 30 percent across much of the area. Will need to monitor this. Fortunately, winds will remain light on Thursday. && .AVIATION... 18Z Update... Primary concern is any chance for smoke or radiational cooling fog reducing visibility. Do not expect IFR vsbys at ATL but other airports could get close. Mid level clouds will clear after 06Z tonight with SKC expected after. //ATL Confidence...18Z Update... Medium confidence in smoke trajectory and concentration/ visibility forecast. High confidence for all other elements. SNELSON && .PRELIMINARY POINT TEMPS/POPS... Athens 46 70 44 74 / 0 0 0 0 Atlanta 49 70 48 75 / 0 0 0 0 Blairsville 41 64 38 74 / 0 0 0 0 Cartersville 43 69 42 76 / 0 0 0 0 Columbus 50 73 47 78 / 5 0 0 0 Gainesville 48 68 46 73 / 0 0 0 0 Macon 45 73 42 78 / 0 0 0 0 Rome 43 71 41 77 / 0 0 0 0 Peachtree City 45 71 41 76 / 0 0 0 0 Vidalia 46 72 46 77 / 0 0 0 0 && .FFC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...SNELSON LONG TERM....41 AVIATION...SNELSON
Area Forecast Discussion
National Weather Service Wilmington OH
356 PM EST Tue Nov 15 2016 .SYNOPSIS... A weak area of low pressure will move east of the region tonight. High pressure will build into the area on Wednesday, as a large mid-level ridge builds into the eastern half of the country through the end of the week. This will bring warmer conditions through Friday. A cold front will cross the area early Saturday, leading to cooler temperatures over the weekend. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... A weak upper low is currently centered over Pennsylvania, helping to clog up the longwave pattern at the moment -- though this is going to be changing soon. A shortwave trough is moving east across the northern Great Lakes, with a weak area of surface low pressure currently passing through the southern Great Lakes and Ohio Valley. The weak forcing and dry air mass (precipitable water of 0.36 inches on the 12Z KILN sounding) will keep rain from developing, but a slowly-moving broken band of clouds will continue to progress eastward tonight. With these clouds moving out, and winds remaining very light, radiational cooling conditions will be near-ideal overnight. Min temps have been lowered with the latest forecast, and most of the ILN CWA is now expected to fall into the upper 30s. Outlying locations may reach the middle 30s. This is slightly lower than both output guidance and SREF means. Based on this forecast and an analysis of current dewpoints -- in addition to support from HRRR projections -- some fog development appears likely tonight. This will especially be true in river valleys, as well as across most of the northwestern quarter of the forecast area. Patchy fog has been included in the grids, and if current trends continue, there may be some chance of dense fog going into early tomorrow morning. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY NIGHT/... As the shortwave currently moving through the Great Lakes gets east of the area, ridging will quickly begin to build in on its back side, with significant height rises and warm advection aloft on Wednesday. It will take some time for boundary layer temperatures to begin to rise, with max temps on Wednesday appearing similar to (or just higher than) Tuesday. Neutral surface advection will switch to warm advection by Thursday, before really ramping up on Thursday night as the pressure gradient tightens. This will combine with continued warm advection aloft, as 850mb temperatures are forecast to go from about 5-6C (18Z Wednesday) to about 13-14C (00Z Friday) over KILN. This will result in a significant boost in max temperatures from Wednesday to Thursday, and NAM/GFS soundings suggest values in the middle 60s (central Ohio) to around 70 (Cincinnati area). These values are notably higher than any SREF members, which only peak out in the mid 60s, and have a mean that is a solid 8-10 degrees below the current forecast. This warmth is anomalous -- very close to record temperatures at 850mb for mid-November, per SPC sounding climatology. With that said, record highs appear safe for Thursday. Outside of the warming temperatures and the switch to southerly flow, very little else is expected to occur during the short term of the forecast. There are still a few discrepancies in the models with regards to handling some leftover low level moisture from Wednesday morning through Thursday morning, with RHs appearing rather high on the NAM. More than likely, skies will remain mostly clear through this period, with cirrostratus sliding in from the west by Thursday afternoon. && .LONG TERM /FRIDAY THROUGH TUESDAY/... Decent southerly flow on Friday will allow for well above normal temperatures. Current forecast values are below record values. The high temperature forecasts for Friday are CMH 71, CVG 71, and DAY 70. The record values are CMH 73 in 1954, CVG 76 1930, and DAY 75 1930. A strong cold front will move through Friday night into Saturday morning. Precipitation will move through with this feature. Expect mainly rain, however some snowflakes will also be possible. Some lingering precipitation will be possible through the day on Saturday and also on Sunday with the upper trough and also some lake enhancement. As colder air continues to move in later in the day on Saturday expect most of the remaining precipitation to transition over to snow showers. Precipitation will taper off Sunday evening into Sunday night. Winds will pick up with the cold front and remain gusty through the weekend. Model soundings are indicating 30 to 35 knots Saturday into Saturday night and with cold air advection scenarios this is sometimes underdone. Expect the highest wind gusts Saturday into Saturday night when wind gusts of 30 to 40 mph will be possible. A few isolated higher gusts will be possible. Gusty winds of 25 to 35 mph will be possible on Sunday before decreasing. Mentioned wind gusts in the HWO for locations north of Cincinnati. High pressure and dry conditions will be present for Monday into Monday night. Models diverge after this point with the GFS much faster than the ECMWF in bringing precipitation into the area. Trended with the slower ECMWF solution for now and only bring a slight chance of rain showers into the area during the day on Tuesday before increasing precipitation chances to the chance category overnight Tuesday night. && .AVIATION /21Z TUESDAY THROUGH SUNDAY/... A weak trough axis will push east through the region this afternoon into this evening. Some moisture is associated with this feature in the form of SCT-BKN 4000-7000 foot ceilings. For tonight, skies should clear behind the trough axis, with perhaps a few altocumulus and/or cirrus passing by into the early morning hours. The biggest forecast dilemma will be for the late night into Wednesday morning. Some models indicate that perhaps the low levels near the surface may saturate and form either low stratus ceilings and/or fog, while others keep the low levels dry. Confidence is low, and as such, have just placed some MVFR visibilities at the terminals, except KLUK, where river fog will likely form with typical near or below airport minimums. On Thursday, a surface ridge of high pressure will build in from the west. Any fog should burn off between 14Z and 16Z with just a few cirrus clouds expected thereafter. OUTLOOK...MVFR ceilings and visibilities possible Friday night and Saturday. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...None. KY...None. IN...None. && $$ SYNOPSIS...Hatzos NEAR TERM...Hatzos SHORT TERM...Hatzos LONG TERM...Sites AVIATION...Hickman
Area Forecast Discussion
National Weather Service Lincoln IL
243 PM CST Tue Nov 15 2016 .SHORT TERM...(This evening through Wednesday) ISSUED AT 227 PM CST Tue Nov 15 2016 A surface trough axis currently analyzed from Minnesota to eastern Kansas will push slowly eastward into Illinois tonight. With little to no moisture to work with, am expecting no sensible weather with the arrival of the trough. As winds become light/variable and skies remain mostly clear, the potential exists for fog development overnight. Both the 12z NAM and 16z Rapid Refresh soundings suggest at least patchy fog...much like what was observed last night. HRRR continues to favor northern Illinois into northern/central Indiana for possible widespread dense fog, with only minor visby reductions further southwest into the KILX CWA. Since the airmass remains essentially unchanged, will follow a persistence forecast and include patchy fog across much of central Illinois later tonight. Once the fog dissipates, mostly sunny and warmer conditions will be on tap for Wednesday. Surface winds will initially be light and variable...then will become S/SE by late afternoon. Given very weak advection and the continued easterly component to the low-level flow, have remained close to numeric guidance for highs...with readings topping out in the lower to middle 60s. && .LONG TERM...(Wednesday night through Tuesday) ISSUED AT 227 PM CST Tue Nov 15 2016 Main forecast concern continues to revolve around the strong storm system and its affect on our area Friday, followed by much colder weather for the weekend and into early next week. Surface high pressure will drift off to our east Wednesday night as the deep trof and associated surface low pushes into the Plains by Thursday morning. This should allow an increasing southerly flow to develop over our area late Wednesday night and especially during the day on Thursday which should help propel temperatures close to or above record levels in many areas (See Climate section below). Winds are expected to gust between 30 and 35 mph out of the south by afternoon as highs soar into the low to mid 70s with a few upper 70s possible across parts of extreme west central Illinois. Those gusty winds should continue Thursday night as the surface low tracks into northern Iowa by Friday morning. Initially, moisture transport ahead of the front Friday morning is not very impressive, but as the front shifts east during the day the persistent southerly flow will eventually draw moisture north out of the Gulf of Mexico, with the NAM12 indicating mid 50 dew points into parts of southeast and east central Illinois Friday afternoon. Still not seeing much surface based instability with those dew points but it should be interesting to see how models adjust in the next several runs with low level moisture transport immediately ahead of the front. Wind shear is not lacking to say the least with 0-6km bulk shears in the 60-70 kt range, but that in itself may be a detriment to any sustained updrafts ahead of the surging cold front Friday afternoon. Still the threat for some quick moving, low topped storms to develop between I-55 and I-57 early in the afternoon and then push east with the front into Indiana by 00z where it will start to catch up to a more favorable moisture profile. Highest POPs Friday afternoon will be along and east of the Interstate 57 corridor with likely POPs indicated, while decreasing rain chances will be the story to the west behind the cold front. As the cold front continues to race away from the area Friday evening, we should see the rain chances move out of the entire forecast area by late evening before some wrap-around moisture shifts southeast behind the departing storm system early Saturday morning. May see some brief sprinkles or flurries early Saturday morning thanks to the deep cyclonic flow/strong cold advection across the area with models now trending faster with the surface low exiting the region and the resulting wrap-around moisture, so have backed off any mention of the sprinkles or flurries in the forecast for now. Windy and much colder weather will be the story for Saturday with highs mainly in the 40s. The combination of the gusty winds and morning lows around 30 in our northern counties will yield wind chills in the upper teens to lower 20s Saturday morning! Morning lows on Sunday will drop to between 20 and 25 degrees with wind chills of between 10 and 15 degrees. Chilly weather will dominate the weather across the area Sunday through Monday night, although winds will be considerably lighter than what we will have across the area on Saturday. Afternoon temperatures Sunday and Monday should be in the low to mid 40s with temperatures moderating back to around 50 on Tuesday. By Tuesday, another storm system should take shape to our southwest with precip breaking out in the warm advection regime to our west and south Tuesday morning and gradually spreading northeast into our area during the day Tuesday. Models not showing much, if any agreement with the speed of the system and timing of precipitation into our area, with the GFS much quicker in pushing the storm and precip off to our east Wednesday, while the ECMWF is quite a bit slower and keeps precipitation going across our area into Thanksgiving morning. For now, POPs starting to increase from southwest to northeast Tuesday morning, with even the possibility for a brief period of a very light rain/snow mixture for a couple of hours Tuesday morning, with rain chances taking over late morning through the remainder of the day Tuesday. && .AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon) Issued at 1145 AM CST Tue Nov 15 2016 Main aviation forecast concern will be the possible re-development of fog tonight. A weak trough axis currently over Nebraska/Kansas will push into central Illinois...resulting in light/variable winds tonight. Other than a few high clouds, skies will be mostly clear. Since the airmass will essentially be unchanged, it seems a persistence forecast would be most prudent in this case. Patchy fog developed at all terminals last night, with KCMI briefly experiencing visbys of less than 1 mile. Think the same will be true tonight, although it is difficult to pinpoint exactly where thicker fog may develop. Based on latest HRRR forecast, it appears northeast Illinois into northern Indiana will be favored for potential dense fog late tonight into Wednesday morning. At this time, will include 2-4 mile visbys at all TAF sites between 09z and 16z. && .CLIMATE... Issued at 235 PM CST Tue Nov 15 2016 Record high temperatures for Thursday, Nov 17th... Peoria........75 degrees set back in 1941 Springfield...75 degrees set back in 1941, 1952 Lincoln.......75 degrees set back in 1941 Galesburg.....75 degrees set back in 1952 Jacksonville..78 degrees set back in 1952 Bloomington...78 degrees set back in 1986 Decatur.......77 degrees set back in 1952 && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Barnes LONG TERM...Smith AVIATION...Barnes CLIMATE...EJL
Area Forecast Discussion
National Weather Service Sacramento CA
1030 AM PST Tue Nov 15 2016 .SYNOPSIS... A weather system will bring a chance of showers to much of the region today and tonight with lingering showers over the mountains on Wednesday. Dry weather returns Thursday and Friday before another wet weather system approaches for next weekend. && .Discussion... Frontal band across OR and NWrn CA has been enhanced by short wave energy as it approaches the Nrn CA coast and showers have spread across the Nrn zones this morning. Radar shows isolated showers behind the frontal band as the cooler/unstable air nears the coast. With the short-wave energy mainly skirting to the N and across OR later today and tonight...the front will weaken as it heads SEwd across interior Norcal. The latest CNRFC QPF and HRRR high resolution QPFs significantly weaken the QPF as the frontal band shifts SEwd leading to only low PoPs across much of our CWA, except the Nrn and Ern zones. Snow levels will remain above pass levels today, so no travel impacts expected. The main short wave energy is forecast to move across Norcal late tonight and Wed morning but moisture will be lacking. Given the dynamics can`t rule-out isolated to scattered showers across Norcal during this time, mainly for the mountains. Lowering snow levels may lead to some light snowfall accumulations expected across the higher elevations. By Wed afternoon, large scale ascent will have shifted E of the Sierra Crest and subsidence will prevail. Temperatures will lower about 15-20 degrees by Wednesday compared to Monday`s readings. Some moderation of the airmass, and a return of dry weather is expected by Thursday as ridging returns. The strongest warming will be over the foothills and mountains, while strengthening inversions and poor mixing may limit the amount of warming in the Central Valley later this week. /JHM && .EXTENDED DISCUSSION (Saturday THROUGH Tuesday) Widespread precipitation and cooler temperatures are expected over the weekend as a cool trough with a surface cold front moves through Norcal. Models are a little slower bringing this system in, with precipitation not reaching eastern portions of the forecast area until later Saturday evening or possibly until early evening. The best potential for precipitation continues to be over the Coastal Mountains and Shasta County...where over 2 inches of rain could fall. Locations further south and east should see lesser amounts, especially if the GFS is correct in slowing/stalling the frontal boundary on the west side. Early estimates of snowfall suggest a few inches around pass levels in the Sierra, potentially 6-12 inches at Lassen National Park. Anyone traveling over the mountains this weekend should closely monitor forecast updates for more information on potential winter travel impacts. Some showers many linger into early next week as weak ridging returns with moist flow. Most shower activity should be in the mountains and foothills and Valley north of I80. Another shortwave could bring more precipitation on Wednesday. EK && .AVIATION... A frontal band moving inland from the coast is spreading light precipitation into the northern Coastal Range. This should reach RDD around 12z this morning. Light rain with MVFR conditions could reach the Sacramento area by around 20-21Z. Patchy IFR/LIFR fog Tuesday morning has developed this morning in the vicinity of KSCK and should diminish by around 17-18z. EK && .STO WATCHES/WARNINGS/ADVISORIES...None. && $$
Area Forecast Discussion
National Weather Service Tallahassee FL
222 PM EST Tue Nov 15 2016 .NEAR TERM [Through Tonight]... A shortwave will push through the CWA tonight with a weak front moving through overnight as well. There have been some showers and low to mid levels clouds associated with this system over Alabama this afternoon. As the wave moves through the CWA tonight, will see a slight increase in cloud coverage, however based on the latest visible satellite loop there is somewhat of a decreasing trend in the clouds and thus do not expect cloud coverage over the CWA to be quite as extensive as it is now over central AL. With the dry air in place, there is also a dissipating trend with the showers over central AL. HRRR has been trending toward the showers making it further east than initially expected and given latest radar trends, can`t rule out a light shower or sprinkle making it to the northwest part of the CWA. Given this, have added a slight chance of showers to mainly our AL counties before 00z tonight. Rainfall amounts would be minimal. With some clouds persisting into tonight will see low temperatures a few degrees warmer than this morning with lows Wednesday morning in the mid to upper 40s inland and low to mid 50s along the coast. .SHORT TERM [Wednesday Through Thursday Night]... The upper trough that brought a slight increase in clouds today will continue to move off to our east, with light northwesterly flow on Wednesday and an upper level ridge building over our area on Thursday. A large area of high pressure at the surface will also build over our region throughout this period. As a result, dry conditions will prevail under generally clear skies. Highs will range from the mid-upper 70s, with lows dipping to the upper 40s inland under ideal radiational cooling conditions. Lows will be in the 50s along the Gulf Coast. .LONG TERM [Friday Through Tuesday]... Dry weather will likely continue across our area through this period. Deep layer ridging on Friday will be replaced by an upper level trough and fairly strong cold front moving eastward through our CWA on Saturday. Due to a lack of moisture across our area, the front will likely pass through without producing much if any rainfall, and have kept any mention of rain offshore for now. However, it is likely that this front will usher in the coolest temperatures so far this season, with lows forecast to drop into the mid-upper 30s by Monday morning and highs in the 60s Sunday and Monday. Extremely dry air will also push into our area behind the front, ending any chances of rain through early next week as we continue our prolonged period of dry conditions. && .AVIATION [Through 18Z Wednesday]... SKC to begin the TAF period, but clouds will increase this afternoon as an area of mid-level clouds over Alabama moves southeast. There is also an area of showers over the same area, but has been dissipating as it moves southeast. Showers should dissipate before reaching DHN but still a small chance that -RA could make it to DHN. && .MARINE... Northwesterly winds will gradually become easterly later this week, generally remaining around 10 knots. Seas will remain around 2 feet or less until Friday and then increase as a strong cold front moves through our area early in the weekend. Seas could increase to 4 to 6 feet on Saturday night, with locally higher waves possible offshore as northerly winds could increase to 20 to 25 knots. && .FIRE WEATHER... Dry conditions will continue through the rest of the week. Minimum relative humidity values will fall into the mid 20s to mid 30s range away from the coast each afternoon. Winds appear light and below critical thresholds for red flag criteria. && .HYDROLOGY... No significant rainfall is expected for the next several days. && .PRELIMINARY POINT TEMPS/POPS... Tallahassee 48 77 47 79 49 / 0 0 0 0 0 Panama City 55 74 55 75 57 / 0 0 0 0 0 Dothan 48 76 47 79 47 / 0 0 0 0 0 Albany 46 76 46 79 46 / 0 0 0 0 0 Valdosta 46 76 46 78 47 / 0 0 0 0 0 Cross City 47 75 48 77 49 / 0 0 0 0 0 Apalachicola 54 73 55 74 57 / 0 0 0 0 0 && .TAE WATCHES/WARNINGS/ADVISORIES... FL...None. GA...None. AL...None. GM...None. && $$ NEAR TERM...Fieux SHORT TERM...Lahr LONG TERM...Lahr AVIATION...Fieux MARINE...Lahr FIRE WEATHER...Fieux HYDROLOGY...Lahr