Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 09/10/20

National Weather Service Albany NY
1044 PM EDT Wed Sep 9 2020 .SYNOPSIS... A warm and humid air mass will be over the region tonight with some showers moving into locations south of the Interstate 90 corridor after midnight. A disturbance moving along a front south of the region will bring showers and a chance of thunderstorms in the late morning into the afternoon from the Capital Region south and east. A cold front will bring additional isolated to scattered showers and thunderstorms in the afternoon into the evening, as it sweeps across the region. A much cooler and drier air mass will settle into the region Friday into Saturday. && .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/... As of 1030 PM EDT...Forecast remains on track with only some minor adjustments needed based on observational data and trends. Fair through this evening with chances for showers moving into the southern reaches of the forecast area overnight. Milder and muggier than last night. A strong mid and upper level ridge over the western Atlantic will continue along the East Coast tonight into tomorrow with above normal heights. A pair of frontal boundaries will impact the forecast area tonight through tomorrow. The cold front with cooler and drier air will remain north of the St Lawrence Valley tonight associated with a strong northern stream mid and upper level trough. Another frontal boundary along the periphery of the 597 decameter closed anticyclone near the East Coast will drift northward from the Mid Atlantic States and coastal New England tonight. Some over running light rain or rain showers will move towards locations south and east of the I-90 corridor and closer to the I-84 corridor after midnight. An inverted sfc trough and weak mid-level shortwave will enhance the lift and moisture advection with this feature. Some weak elevated instability is indicated by the latest NAM over the southern most zones, so a rumble or two of thunder may possible. Some patchy fog may form north of the area of showers, as their likely will be a sharp cut-off in the cloud shield. A weak sfc high will be over upstate NY and New England early in the period. We placed some patchy fog in the forecast, and it will be a muggy night with sfc dewpts in the upper 50s to mid 60s. Low temps will be in the upper 50s to lower 60s over the higher terrain and north and west of the Capital Region and mid and upper 60s from the Capital Region south and east. && .SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/... Tomorrow...Complicated forecast with the two fronts impacting the forecast area coupled with the weakening ridge. An influx of deeper moisture and tropical like air mass will occur over the southern half of the forecast area with PWATs rising to around 2.0". Further north and west of the Capital Region PWATS will be in the 1.5-2.0" range. The higher PWATs are +2 to +3 STD DEVs above normal based on the 12Z GEFS. Weak impulses moving along the front south of the region could bring isolated to scattered thunderstorms with locally heavy downpours. There are some timing differences in the CAMs, especially with the 3-km NAMnest and the 3-km HRRR. The 3-km NAMnest has some convection and heavier rain showers impacting the area in the late morning into the early afternoon especially south and east of the I-90 corridor. The 3-km HRRR is slower and more in the afternoon period. The model soundings look tall and skinny south of Albany. All this said, increased lift and low-level convergence with the boundary to the south could yield periods of heavy rain with locally heavy downpours. WPC is placing locations south of the Capital Region /southeast Catskills, mid Hudson Valley, southern Berkshires and NW CT/ in the Day 2 Excessive Rainfall graphic with Marginal Risk of exceeding the FFG. The good news is the 1-,3-hr and 6-hr FFG values are high, but intense rainfall rates will be possible. Ponding of water on roadways and poor drainage flooding of low-lying/urban areas will be possible. We will also have monitor for any training. The latest 12Z HREFS does lean to towards an increase of mean SBCAPE values of 1000+ J/kg in the afternoon for locations south and east of the Capital Region and the 0-6 km bulk shear increase to 25-30 kt. Further north, the 0-6 km shear increases to 30-40 kts with the cold front pushing southward in the afternoon for locations north of the Capital Region, but the instability is generally lower in the 250-750 J/kg range. The lower instability will limit updrafts from being tall enough for a robust severe threat. Some gusty winds may be possible from pcpn loading. The mid level lapse rates look weak and overall, convection from the cold front dipping southward looks isolated to widely scattered. Sfc dewpts will be in the 60s to lower 70s. SPC has placed the entire forecast in General Thunder at this time. We likely will have to monitor for a marginal/isolated severe or two. The front makes steady progress in the afternoon and a 2nd round of showers and thunderstorms will be possible in the late afternoon into the early evening over the southern most zones. High temps will likely be held down due to clouds and a moist air mass with highs in the upper 70s to lower 80s in the valley areas, and upper 60s to upper 70s over the higher terrain Thu night...Isolated to scattered showers will decrease especially before midnight over most of the forecast area. A few could linger a little thereafter closer to the I-84 corridor if a weak wave forms and moves along the boundary. Strong cold advection will occur in the wake of the front with H850 temps falling to +6C to +10C from the Capital District north and west, and +10C to +14C south and east. It will becoming breezy from the west to northwest at 5 to 15 mph. Humidity levels will lower and lows will fall into the 50s with some mid and upper 40s over the southern Adirondacks and southern Greens. Friday-Friday night... Cold advection continues in the morning. A broad Canadian anticyclone builds in from the Great Lakes Region. It will be a much cooler and drier air mass. The winds will be northwest to north at 10 to 20 mph. Sfc dewpts will fall into the 40s to lower 50s with even some upper 30s over the southern Adirondacks. High temps will generally be in the upper 60s to lower 70s across the lower elevations, and upper 50s to mid 60s over the mtns. The strong subsidence from the sfc high will yield lots of sunshine. Fri night...the winds should go light to calm, with clear skies, as the sfc anticyclone will be building in over the region for ideal radiational cooling conditons. Lows will be chilly in the 40s to lower 50s with some upper 30s possible in the southern Greens and over the southern Dacks. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... High pressure will slowly push to our east on Saturday but will still bring another dry and partly to mostly sunny day with highs ranging from the 60s in the higher terrain to the low to mid-70s in the valleys. Unsettled weather returns late Saturday night and continues through Sunday night as an upper-level trough (the one responsible for the cold and snow across the Rockies earlier this week) sweeps across the region. At the surface, low pressure over the Upper Midwest will track northeastward with a warm front lifting northward through the region late Saturday night through Sunday morning and a cold front passing through Sunday night into early Monday morning. Strong lift along the warm front should lead to some rainfall as early as Sunday morning (though models differ on start time). As the afternoon progresses, an increase in dew points and precipitable water values (1.50 to 2.00 inch range) along with being in the warm sector of this system will likely lead to additional showers and perhaps a few thunderstorms. The rather cloudy conditions should prevent thunderstorm activity from being too strong, but this will continue to be monitored over the coming days. Some locally heavy rainfall will be possible, though with the rather dry conditions across the region, any rainfall should be beneficial. Otherwise, it will be a breezy day with highs ranging from the mid-60s to the mid-70s. As the cold front pushes through Monday morning, showers will come to an end and clouds will decrease and give way to mostly clear and dry weather for the remainder of the long term period as high pressure returns. There could be a northwesterly breeze on Monday behind the front. Highs Monday through Wednesday will be in the 60s and 70s (with Tuesday likely the coolest day) with lows mainly in the 40s (with a few 30s possible across the higher elevations). && .AVIATION /03Z THURSDAY THROUGH MONDAY/... Conditions will be variable across the region. Lower level clouds will move in from the south overnight into early Thursday morning as a trough of low pressure approaches from the south with MVFR ceilings developing. While at KGFL, MVFR conditions are expected to develop overnight with IFR possible due to radiation fog. Scattered showers are expected to develop/move in from the south early Thursday morning with MVFR conditions and IFR possible at KPOU/KPSF. Chances for showers will spread northward but with lesser coverage as you head northward, so have addressed threat with VCSH in KALB and KGFL TAFs. A period of MVFR ceilings are expected at KALB and possible at KGFL. Light and variable to calm winds through the night with a southerly flow developing Thursday at 6 knots or less. Outlook... Thursday Night: Moderate Operational Impact. Chance of SHRA...TSRA. 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. Likely SHRA...TSRA. Sunday Night: Moderate Operational Impact. Chance of SHRA. Monday: No Operational Impact. NO SIG WX. && .FIRE WEATHER... A warm and humid air mass will be over the region tonight with some showers moving into locations south of the Interstate 90 corridor after midnight. A disturbance moving along a front south of the region will bring showers and a chance of thunderstorms in the late morning into the afternoon from the Capital Region south and east. A cold front will bring additional isolated to scattered showers into the evening periods. A much cooler and drier air mass will settle into the region Friday into Saturday. The RH values will increase to close to 100 percent tonight with some patchy fog, dew formation and scattered showers. The RH values will lower to 40 to 55 percent tomorrow afternoon with showers and thunderstorms moving in. The RH values will increase to 80 to 95 percent Friday morning. The winds will light south to southwest at less than 10 mph tonight, and shift to the west to northwest in the wake of the cold front tomorrow afternoon into the early evening at 5 to 15 mph and will persist through Friday morning. && .HYDROLOGY... Widespread problems are not expected on the main stem rivers the next several days. Isolated to scattered showers and isolated thunderstorms will be possible late tonight for locations south of the Capital Region. Isolated to scattered showers and a few thunderstorms will be possible Thursday as a front moves southward north of the Capital Region. Locations south and east of the Capital Region with have scattered to numerous showers with a chance of thunderstorms with locally heavy rainfall. High PWAT values will allow for intense rainfall rates potentially exceeding an inch or more in an hour. Ponding of water on roadways and urban and poor drainage flooding of low-lying areas will be possible south and east of the I-90 corridor. 1-,3-,and 6-hr FFG values remain high due to the recent dry spell. Total rainfall may range from a a half an inch to an inch and half south and east of the Capital District into Thursday night for some locations. Rainfall amounts should generally be a tenth to a quarter inch north and west of the Capital Region. A cooler and drier air mass builds in for Friday and Saturday which will allow for flows to decrease. A more widespread and soaking rainfall is possible for Sunday- Sunday night as low pressure tracks across 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...Wasula NEAR TERM...IAA/Wasula SHORT TERM...Wasula LONG TERM...Rathbun AVIATION...IAA FIRE WEATHER...Wasula HYDROLOGY...JLV/Wasula
Area Forecast Discussion
National Weather Service Buffalo NY
1031 PM EDT Wed Sep 9 2020 .SYNOPSIS... Temperatures will settle back towards normal values during the next couple the stalled frontal boundary over our region will be pushed to the south by an approaching area of high pressure. The period will be characterized by generally fair...dry weather that will persist through at least the start of the upcoming weekend. && .NEAR TERM /THROUGH THURSDAY NIGHT/... Stratus will spread south of Lake Ontario and across the North Country in the northeasterly flow on the cool side of a frontal boundary which is located just south of Buffalo and Rochester. The front will lift slightly north overnight, which will cause the stratus to move north also, but any clearing combined with increasing moisture from the south is likely to result in fog. HRRR guidance shows the greatest risk for dense fog across the Niagara Frontier, but there`s also a risk for dense fog in the Southern Tier valleys and the North County. Otherwise, fair dry weather will be found across the majority of the region through the period...courtesy of a ridging off the east coast. The only blemish could be a shower or two over the Finger Lakes Thursday afternoon and early evening. Temps will cool through the period. Hemispheric GEM preferred through Thursday...GFS Thursday night. && .SHORT TERM /FRIDAY THROUGH SUNDAY NIGHT/... High pressure centered over the Great Lakes Friday morning will spread eastward into the weekend. Dry weather expected Friday into Saturday. A northeast flow will lead to cooler than normal temperatures Friday with highs in the upper 60s to low 70s. Winds veer to the south-southeast Saturday and warm air advection will move into the region from south to north. Temperatures will climb into the mid to upper 70s Saturday. An upper level trough will move into the western Great Lakes Saturday night and a southerly flow will increase transporting Atlantic moisture into the region. Models are depicting a 100+ kt upper level jet across southern Ontario and Quebec ahead of the trough. The eastern Great Lakes and areas to the southeast will be located in the right entrance region. While it looks like the better mid-level convergence will be south and east of western and north central NY we may have a period of moderate showers with a slight chance of thunderstorms late Saturday night across Western NY. Low pressure will quickly move from the Mid-West to the eastern Great Lakes/southern Ontario region Sunday morning and drag a cold front across the region Sunday. Moderate showers will move into the North Country into Sunday. Showers and thunderstorms will continue through Sunday. Drier air will filter into the region Sunday night and showers will end from west to east. Temperatures will climb into the mid to upper 70s Sunday and into the mid to upper 50s Saturday night and Sunday night. && .LONG TERM /MONDAY THROUGH WEDNESDAY/... Prolonged period of quiet and dry weather appears on tap during this period. High pressure over the Great Lakes will track southeast and provide tranquil weather through at least midweek. Look for highs near to a bit above normal for this period with upper 60s to low 70s. && .AVIATION /03Z THURSDAY THROUGH MONDAY/... Satellite imagery (Nighttime Microphysics) shows stratus and IFR or lower conditions north of a BUF-ROC-ART line late this evening. The front will move slightly north overnight, which may allow a brief improvement in flight conditions after 04Z. However, any clearing also brings the risk of fog to develop, with locally dense fog possible. Greatest concern is across the Niagara Frontier where moisture just to the south will mix with cooler air late tonight. Also expect fog to develop across the Southern Tier valleys again tonight. Conditions will gradually improve Thursday morning, giving way to mainly VFR conditions by Thursday afternoon. Outlook... Thursday night...Mainly VFR. Friday and Saturday...VFR. Saturday night and Sunday...VFR to MVFR with the likelihood of showers and thunderstorms. Monday...VFR. && .MARINE... A stalled frontal boundary will remain south of the lakes overnight. A cold front will move across the waters late tonight into Thursday. A northerly wind will become northeast by Thursday night. This will persist through Friday until winds become west- southwest Friday night. Waves will increase during this time and small craft conditions will be possible. A southerly wind will increase Saturday and Saturday night as a cold front approaches from the west. Showers and thunderstorms are possible Saturday night through Sunday night. Small Craft Advisories will be possible during this time. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...None. MARINE...None. && $$ SYNOPSIS...RSH NEAR TERM...Apffel/RSH SHORT TERM...HSK LONG TERM...AR/HSK AVIATION...Apffel MARINE...Apffel/Hitchcock/TMA
Area Forecast Discussion...UPDATED
National Weather Service Gray ME
1046 PM EDT Wed Sep 9 2020 .SYNOPSIS... A cold front will approach the region from Canada tonight, before slowly crossing the region Thursday through Thursday evening. Drier air follows for Friday and Saturday as high pressure enters the region. Low pressure will pass north of New England Sunday into early morning. && .NEAR TERM /UNTIL 8 AM THURSDAY MORNING/... 1045 PM Update... Temperatures were adjusted slightly overnight based on latest forecast trends. These bring overnight lows down just into the upper 50s across the north, and keeps southern and central sections in the 60s. Most of the coast is reporting dense fog, and this will gradually work its way north by morning. 745 PM Update... Have extended the dense fog advisory a tier northward based on latest HRRR and other guidance. The advisory was also extended until 10 am for the Mid Coast based on this morning`s timing of fog dissipation. The offshore waters may see dense fog through almost noon tomorrow. Otherwise showers continue along a front across southern Quebec and northern ME, and this may bring a few sprinkles to the northern mountains overnight. It is interesting to note that Mount Washington was 61 degrees at 7 pm, almost as warm as our sea level observation sites. Previous discussion... Plenty of low level moisture will advect inland from the Gulf of Maine on relatively light south to southwesterly winds. This will allow for areas of dense fog to develop once again over southern locations. Have issued a dense fog advisory for the coast and one row of zones inland due to visibilities dropping to a quarter mile or less. The dense fog will be more patchy well inland. Latest mesoscale models suggest tropical moisture off the Mid Atlantic region may attempt to advect into far southern portions of our region embedded within the low level south to southwesterly flow. Latest radar imagery continues to show some of this moisture advecting poleward towards the southern New England coastline. Have added low chance pops for late tonight with this feature. It will remain muggy tonight with overnight lows mainly in the upper 50s to lower 60s, very close to forecast dew point values. && .SHORT TERM /8 AM THURSDAY MORNING THROUGH THURSDAY NIGHT/... Dense fog lifts Thursday morning. Clouds expected with the southern New England tropical moisture with scattered showers expected south. Highest chance for rainfall will be over southeastern New Hampshire. Over northern sections, scattered showers are expected along and ahead of an approaching cold front. CAPE values increase during the day, sufficiently enough to possibly trigger a thunderstorm or two during the day. After some scattered showers in the south Thursday evening, the precipitation will exit off the coastline as the front shifts offshore. Some fog may develop over and along the coastline, however a drying trend with northwesterly winds can be expected by late at night as high pressure builds into the region. && .LONG TERM /FRIDAY THROUGH WEDNESDAY/... Early in period a frontal boundary will push offshore allowing high pressure over the Great Lakes to push east. This will result in rapidly clearing skies early Friday in a fresh northerly flow. The high will rapidly push east reaching Northern New England Friday Night. The high will move east of the area during the day Saturday. This will result in clear skies giving way to mid and high level clouds later in the afternoon as low pressure moves east from SW Ontario Province. The low will track north of the area keeping the heaviest precipitation to the North and West of the region...however the associated frontal systems with the low will increase the likelihood of showers Sunday and Sunday evening. High pressure will build back in from Southern Canada early next week. After a relatively warm stretch expect temperatures to trend cooler and become more seasonable. Models: Will be initializing with the NBM. Global models are in better than average agreement over this period. There are slight QPF differences for Sunday but nothing significant. The Canadian is the driest and the GFS is the wettest but all amounts are relatively low...under a quarter of an inch south of the mountains. The GFS is about 6 hours faster for the onset of any showers. The NBM POPS are a bit high this far out given that most precip events have under performed in recent weeks. Will therefore reduce pops about 15% across the board Sunday. Otherwise the blend is in good shape. && .AVIATION /03Z THURSDAY THROUGH MONDAY/... Short Term...Areas of IFR and LIFR conditions developing in low clouds and dense fog along and near the coast tonight. Patchy dense fog possible once again over the interior. Long Term... Generally VFR to MVFR conditions through Saturday Night. Areas of IFR developing in showers Sunday into Sunday night as a cold front approaches and then crosses the region. VFR conditions return Monday as high pressure builds in. && .MARINE... Short Term...Areas of dense fog will redevelop over the waters this evening and continuing into early Thursday. Some fog to redevelop over the waters Thursday evening. Long Term... Waves and wind below SCA through Sunday Morning. Waves will build to SCA levels as southerly winds increase ahead of low pressure to our north. A cold front will shift winds to the NW Monday into Tuesday with waves at or above SCA levels at the end of the fetch. && .MARINE... Short Term...Areas of dense fog will redevelop over the waters this evening and continuing into early Thursday. Some fog to redevelop over the waters Thursday evening. Long Term... Waves and wind below SCA through Sunday Morning. Waves will build to SCA levels as southerly winds increase ahead of low pressure to our north. A cold front will shift winds to the NW Monday into Tuesday with waves at or above SCA levels at the end of the fetch. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...Dense Fog Advisory until 9 AM EDT Thursday for MEZ012>014- 018>026-033. Dense Fog Advisory until 10 AM EDT Thursday for MEZ027-028. NH...Dense Fog Advisory until 9 AM EDT Thursday for NHZ010-013-014. MARINE...None. && $$ NEAR TERM...Hanes SHORT TERM...Cannon LONG TERM...Lulofs
Area Forecast Discussion
National Weather Service Blacksburg VA
1002 PM EDT Wed Sep 9 2020 .SYNOPSIS... A strong stationary front will extend from New England into the Mid Mississippi Valley through Thursday with another weaker front along the southeast coast of the United States, while high pressure was over the Mid Atlantic region in between the two fronts. This weather pattern will result in a periods of rain across the area through Friday. The northern front may cross through the area at the end of the week. && .NEAR TERM /THROUGH THURSDAY/... As of 1002 PM EDT Wednesday... Intermittent pockets of showers and drizzle continue to rotate through the area this evening. Radar continues to show most of this out over the Piedmont back into the Roanoke and New River Valley. The heaviest rain continues to stay to our east out over Richmond back to the Virginia Tidewater where the front lingers. Hi-res guidance including the HRRR and ARW continue to paint the steadiest rain east of the area overnight as another wave of energy moves overtop of the western Atlantic ridge. Low clouds and areas of fog will continue to remain in place area-wide when showers are not pivoting on through. Dense areas of fog are expected early Thursday morning west of the Blue Ridge thanks to some holes in the clouds allowing for better radiational and the extra moisture overhead. The easterly component remains though so more gray than sun in most locations Thursday at least to start. Some sunshine may break through by mid afternoon especially off to the west of the I-81 stretch since these locations are on the outer periphery of the wedge. Even with that said conditions should look fairly similar to Wednesday with passing showers and a few diurnally driven storms especially where we can maximize daytime heating. Overnight lows look to fall back into the low to mid 60s out west with upper 60s and low 70s out into the Piedmont. Highs Thursday back int0 the mid to upper 70s and low to mid 80s. As of 549 PM EDT Wednesday... A gray and gloomy evening with a few pockets of light shower and drizzle activity moving on through. Most of our shower activity today has been confined to the east out over Appomattox, Buckingham, Halifax, Caswell, Campbell, and Pittsylvania counties. These areas are closest to the stalled frontal boundary off the Virginia Tidewater and a shortwave piece of energy in the upper flow rotating northeast around the upper ridge over the western Atlantic. Downslope can be noted where shower coverage has been minimized throughout the day and a few breaks of sunshine have been allowed to poke through. Off to the east of I-81 and out over the Piedmont southeasterly upslope flow has allowed a rich transport of PWATS around 1.9 to 2.2 inches to work on in. For that reason went ahead to keeping numerous showers and light to moderate pockets of rain in these areas areas tonight with a tapering of precipitation chances to around 20-40 percent west of the I-81 corridor. A few rumbles of thunder cannot be ruled out the rest of this evening but as of now the overall threat looks to be pockets of showers, low clouds, and fog heading into the overnight hours. Adjusted temperatures a bit to reflect where pockets of sunshine have been noted out over the North Carolina mountains and back across portions of southern West Virginia as well as the New River Valley. Overall most locations continue to hang in the mid to upper 70s with upper 60s and low 70s out east over the Piedmont. Temperatures look to fluctuate a degree or two over the next few hours but look to remain relatively steady through the overnight period with the clouds and excess moisture overhead. The only exception to this would be out west over the mountain where some breaks could be noted thanks to downslope pushing lows in to the upper 50s and low 60s overnight. Areas of dense fog to start Thursday morning with pockets of drizzle and mist rolling on through. Low clouds should lift a bit by mid morning with a few leftover showers out east according to the latest hi-res guidance. Another shortwave looks round our ridge out over the western ATlantic with another wave of showers and even a few scattered thunderstorms Thursday afternoon as more tropical moisture pumps in. High temperatures look to be similar to Wednesday with highs in the low to mid 70s out over the mountains and mid to upper 70s to about 80 east of the Blue Ridge. Confidence remains moderate for overall precipitation and temperatures in the near term. Timing remains an issue overall with the modeling on timing the waves and placement of shower and thunderstorm activity as it rounds the ridge. && .SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY NIGHT/... As of 225 PM EDT Wednesday... The short term remains active with the region remaining on the NW cusp of high pressure. Shortwaves within the flow, combined with diurnal heating and ample moisture with PWATs 1.5-2.0 standard deviations above normal will result in ample opportunities for showers and embedded thunderstorms. While areawide totals won`t remain very high, training and terrain influenced convection could result in amounts greater than 1.5 inches in places. This ample rainfall over multiple days, following rain from Thursday, will likely lead to flooding complications. Saturday, a backdoor front enters the region while high PWATs remain, resulting in continued rainfall with ample cloud cover and below average temperatures. It won`t be until Saturday night that we start to look for an actual cold front to bring a change in the overall weather patter. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... As of 225 PM EDT Wednesday... A shortwave trough to our west will get picked up and exit through Canada on Sunday. The cold front associated with this trough will makes it way eastward to the Mid-Atlantic Sunday afternoon, bringing yet another round of rain. After the front fully exits the region after Monday, drier conditions with cooler temperatures returns. That means that the conditions we just let go with highs in the 70s/low 80s will come back, as well as nighttime lows making their way down into the 50s for many. && .AVIATION /02Z THURSDAY THROUGH MONDAY/... As of 752 PM EDT Wednesday... Our wedge continues to hold as we remain sandwiched between a cold front to our west over the Ohio River Valley and a stationary front along the Carolina/Virginia coast. East to southeast flow will continue to pump rich Atlantic moisture into the area tonight and throughout the day Thursday. This will lead to additional pockets of scattered showers and drizzle especially east of the Blue Ridge and foothills through the overnight into early Thursday morning. Overall we will continue to bounce between VFR and MVFR conditions through this evening especially at KDAN and KLYH since they sit closest to the coastal front. Ceilings though look to lower to IFR/LIFR mainly after 02z/10PM tonight. Besides the low ceilings expect areas of fog overnight through early Thursday morning especially in those typical valley west of the Blue Ridge. Widespread low clouds will continue as fog lifts tHursday morning. More low clouds along with additional waves of showers and storms heading into Thursday afternoon. Winds will remain relatively light out of the east to southeast direction through the TAF period. Average confidence on visibility, ceilings, precipitation, and wind. Below average confidence on timing and placement of diurnally driven storms within the period. .Extended Aviation Discussion... Extensive cloud cover and daily chances for showers and thunderstorms are expected through the period as the Atlantic moisture remains in place across the region resulting in a moist, warm, humid, and unsettled weather pattern. Prolonged periods of sub-VFR conditions are likely. Drier air may arrive early next week. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...None. NC...None. WV...None. && $$ SYNOPSIS...AMS NEAR TERM...ET SHORT TERM...RR LONG TERM...RR AVIATION...ET/KK
Area Forecast Discussion
National Weather Service Tampa Bay Ruskin FL
821 PM EDT Wed Sep 9 2020 .UPDATE... Latest RAP model locates an inverted trough from the southeast Gulf of Mexico to northeast FL that eases westward later tonight and Thu. Deep southeasterly flow moves in behind the trough and helps maintain a moisture rich atmosphere. Model PWAT values run 2.2 to 2.5 inches through tonight into Thu. Afternoon showers and storms produced some gusty winds and localized street flooding earlier but have pushed offshore...leaving some light rain behind mainly in the north. The showers and a few storms will continue over night as they drift slowly west...the rain will be ending within the next couple of hours. The rest of the night on land should be dry although there may be some brief low cloudiness toward sunrise. Have adjusted the forecasts for the next few hours to better reflect current and near term conditions. && .AVIATION... 10/00Z TAFs. Afternoon convection has cleared the aerodromes with prevailing VFR with FEW-SCT low clouds under a BKN middeck. However...there could be some OCNL BKN ST late night but will hold at SCT. Southern terminals will see VCSH AFT 15Z then VCTS AFT 18Z for all sites. Brief MVFR TSRA 20-23Z. Light E winds become VRB to calm over night then E or SE AFT 15Z. Winds at TPA/PIE/SRQ shift to onshore in the afternoon. && .MARINE... An inverted trough in the eastern Gulf slowly exits to the west as high pressure...with a relaxed gradient...builds in from the northeast during the rest of this week. This keeps southeast and east winds in place although shifting to onshore near the coast in afternoon sea breezes. Isolated to scattered thunderstorms will result in locally higher winds and seas. && .Preliminary Point Temps/PoPs... TPA 76 90 76 92 / 40 70 50 70 FMY 75 91 75 92 / 20 70 50 70 GIF 74 91 74 92 / 20 70 30 80 SRQ 75 91 75 92 / 30 70 60 60 BKV 73 91 74 92 / 40 70 50 70 SPG 76 90 76 92 / 40 70 60 60 && .TBW WATCHES/WARNINGS/ADVISORIES... FL...None. Gulf waters...None. && $$ UPDATE/AVIATION/MARINE...09/Rude UPPER AIR...42/Norman DECISION SUPPORT...42/Norman