Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 11/01/22

Area Forecast Discussion
National Weather Service Charleston SC
1037 PM EDT Mon Oct 31 2022 .SYNOPSIS... A weak disturbance will bring unsettled weather to our area through tonight. High pressure will then prevail across the region the rest of this week. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/... A few showers have finally developed in association with a pre- frontal trough near and west of US-301, while showers offshore have decreased in areal coverage from earlier. With continued poor MLCAPE, lapse rates and instability, we don`t foresee too much potential for anything more than isolated to maybe scattered showers into the overnight period. Guidance continues to indicate the potential for fog, some of which will be dense. the highest probabilities from the NARRE- TL, LAMP, NBM and SREF look to be over our South Carolina counties into the coastal corridor of Georgia late at night. Other guidance such as the RAP, HRRR and NAM also have some potential across interior Georgia. Since there is this discrepancy we hold onto the mention in all counties for the Hazardous Weather Outlook. The overnight forecasters can fine tune this as necessary. It`ll be an exceptionally warm night with elevated dew points and a southwest synoptic flow. Not quite at record levels, but a solid 10-12F above climo, or at min values more typical late September/early October, or mid May. Previous discussion... The main moisture convergence and the higher MLCAPE of around 1500 J/kg will stay offshore and out near the Gulf Stream. This is where the better chances of showers will occur early on. There is less moisture convergence and lower MLCAPE near 1000 J/kg situated near and west of the local counties. Eventually some showers will form in proximity to those conditions, but based on recent temp trends we have decreased PoP early on. While we can`t entirely rule out a clap of thunder, since the HREF 1 hour t-storm probabilities are less than 10% and CINH will continue to increase, we have removed mention of t-storms from the forecast. With drier air aloft and considerable boundary layer moisture, plus winds going light or calm, there is the potentially for fog late tonight into Tuesday morning. Favorable condensation pressure deficits and FSI values, moderate probabilities from the SREF and HREF, and utilizing the LAMP guidance which did outstanding last night with the dense fog, we have added mention of a possible Dense Fog Advisory to the Hazardous Weather Outlook. The main negative factor might be the showers that could prevent it from occurring. We will continue to monitor through the night. && .SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY/... Tuesday: To begin the day, a weak cold front will be situated along the coast. Throughout the morning, high pressure will build into the region and push the cold front offshore and further away. By afternoon, drier air moving in will keep the day rain-free. With rising heights and thicknesses, high temperatures will be warm for this time of year. Highs are forecast in the upper 70s to mid 80s. Overnight, shortwave energy will approach from the west but with subsidence in place, have maintained a dry forecast. Although, there could be a few sprinkles, especially across the waters. Low temperatures will be in the mid 50s to mid 60s. Wednesday: Mid-level low pressure to the north will slowly drift eastward throughout the day. Then overnight, it is expected to shift southward. While the impacts should be limited by this feature, an uptick in moisture is possible. At this time, with high pressure lingering at the surface, any chance of shower development will be quite limited due to extensive dry air. As for cloud cover, the day will start with partly to mostly cloud skies then slowly clear out by the overnight. High temperatures will be a few degrees cooler than previous days. The forecast calls for mid 70s to low 80s. Low temperatures will be in the 50s. Thursday: The aforementioned mid-level low will continue to shift offshore into the Atlantic as a mid-level ridge builds in the Gulf of Mexico. At the surface, high pressure will prevail. Therefore, another rain-free day is expected with limited cloud cover. The only exception will be over the waters where there could be a few sprinkles, especially in the overnight. High temperatures will be in the mid to upper 70s. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... Mid-level ridging will shift into the region on Friday and then drift northeast through the weekend. To the west, a mid-level low will shift east while a cold front races across the U.S. While most of the area is forecast to remain rain-free through the majority of the period, there could be showers across the coastal waters and just along the coast. Although, the forecast could change based on the timing of the cold front. High temperatures will be in the mid 70s to mid 80s with lows in the mid 50s to mid 60s. && .AVIATION /03Z TUESDAY THROUGH SATURDAY/... All of the terminals will stay VFR through late tonight, before stratus and fog develops within a very moist boundary layer featuring a 2 to 3C inversion off the surface. Timing is a bit uncertain since a cold front will be approaching, but leaning toward climatology and the model consensus, we have MVFR conditions developing at 08Z, with a period of IFR or even LIFR to occur from 09-13Z. Our 00Z TAFs have conditions down to 2SM in BR and OVC005, but even lower visibilities and/or ceilings are likely. That potential will be addressed in the next TAF set. The inversion lifts quickly by mid to late morning, allowing for VFR to return. Meanwhile, since the risk for showers in association with a cold front and pre-frontal trough is so low tonight, this does not require a mention with the latest TAF set. Extended Aviation Outlook: Prevailing VFR. && .MARINE... Tonight: Winds are forecast to veer from the SE to S early on to the SW by late tonight as a cold front approaches from the west. Winds speeds are expected to remain around 10 kts or less. Seas are forecast to range from 2 to 4 ft. Areas to patchy fog and low clouds are expected to develop over land late tonight, and if the winds can turn more toward the W close to daybreak or thereafter, the fog would drift over the Charleston Harbor and along the immediate coastal waters of GA and SC late into Tuesday morning. We will closely monitor for a possible marine Dense Fog Advisory Tuesday through Saturday: Overall, high pressure will prevail at the surface while a mid-level low to the northwest shifts east then drops south and offshore by late week. West winds on Tuesday at 5 to 10 knots with seas less than 3 feet are expected. Thereafter, the pressure gradient will tighten and Small Craft Advisories will be possible come Wednesday for winds and seas and persist through at least early weekend. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...None. SC...None. MARINE...None. && $$ NEAR TERM... SHORT TERM...RAD LONG TERM...RAD AVIATION... MARINE...
National Weather Service Eureka CA
251 PM PDT Mon Oct 31 2022 .SYNOPSIS...A potent cold front will approach the North Coast late tonight, and then move across the area Tuesday bringing rain to the valleys, snow to the high mountains and gusty westerly winds. Much colder temperatures, mountain snow showers and valley rain showers are expected in the colder air behind the front Tuesday night through Wednesday. High pressure will start to build Wednesday night through Thursday, bring drier weather to Northwest California. Freezing temperatures and frost in the valleys are probable each morning Wednesday through Friday. A series of fronts will bring more rain and mountain snow this upcoming weekend. && .DISCUSSION...Satellite imagery showed a frontal boundary stretching southwestward from central Oregon to about 40N west of 135W as of 2 PM. A wave has been slowing the eastward progression of the front. The bulk of the rain will most likely not reach land areas til late tonight due to this slower eastward progression. Most of the forecast area will remain dry this evening. There are a couple of caveats. Rain chances will increase above 50% after 8 PM for the Del Norte county coast, though the heavier rain rates will probably hold off til after 11 PM. Also, a few light showers or sprinkles may also occur around the Humboldt Bay after about 8 PM (20% chance). By far, the bulk of the rain will occur after 11 PM or more likely toward early morning Tuesday for much of the North Coast. The front will move south and east across the remainder of the area Tuesday morning, providing much needed rainfall to the entire the forecast area. Rain amounts will probably taper off for the far southern portion of the forecast, through southern Lake county could get 0.25 of an inch of storm total rain. The moisture with this front is not very high, PWATS less than 1 inch. The front has strong dynamics and thermal advection which will aid in the upward vertical motion and higher rain rates intersecting with the coastal terrain early Tuesday. About 1 inch of storm total rainfall will be possible for Del Norte, portions of Humboldt and portions of northwest Mendocino counties by afternoon Tuesday. It will be a quick shot of rain. Models indicate the rain quickly winding down for the North Coast by mid morning Tuesday right behind the front. Gusty westerly and northwesterly winds will probably develop after frontal passage. The strongest gusts to 30 or 40 mph will be confined to higher elevations/ridges and most likely localized. The coldest air so far this fall (-2C at 850mb) will follow in the wake of the front on Tuesday. Most of the precipitation will probably occur in the colder air behind the front Tuesday morning. Snow levels will rapidly fall to 4500-5000 feet Tuesday morning. HRRR and multi-model guidance indicates 12 hour accumulations of 2 to 3 inches for Scott Mountain Pass. Thus, a winter weather advisory has been hoisted for northern Trinity county, particularly for Scott Mountain Pass on highway 3. The ground may still be too warm for the snow to stick on the road. Snow levels will continue to lower Tuesday night through Wednesday, however snow amounts may not be sufficient to warrant additional advisories, generally under an inch. The high mountain peaks in Del Norte and northern Trinity counties above 5000 feet will probably have 6 inches or more through Wednesday afternoon. The potential for thunderstorms will also begin to increase Tuesday afternoon and evening for mostly the northern coastal waters and the North Coast as 500mb temperatures fall to -30c or less and lapse rates steepen. CAPE as usual with these maritime cold air outbreaks from the Gulf of AK will be low, under about 200j/kg. The trough aloft does look to acquire a slight negative tilt which may help to promote upward motion and offset the downward vertical motion associated with deep layer cold air advection. A secondary perturbation in the NW flow aloft will follow early Wednesday and may increase the potential for low top thunderstorms. The potential for small hail is still not looking very great at this point. The depth of the near surface warm layer should decrease Tuesday night and early Wednesday morning which should allow some hail particles to reach the surface before melting. The ground may be still be too warm for any accumulations. High pressure will begin to build into the area Wednesday night into Thursday. Drier weather and much colder temperature are expected. Coastal area may still have some showers, mostly over the waters into Thursday morning. Guidance at the moment indicates easterly winds which will likely keep the shallow convection offshore. We are probably going to have freezing and subfreezing temperatures for many interior valleys Wed-Fri. Coastal areas may also have frost and freezing temperatures, however confidence is not as high with the potential for some cloud cover. Deterministic models and ensemble means indicate another trough sagging from the NW toward the latter portion of the week into early next week. The timing and depth of this trough is uncertain. Deterministic GFS and deterministic ECMWF has the first front moving across the area on Saturday followed by another one Sunday. It does look like we will stay in a cool and wet pattern for the next 7 days, though details are up in the air. && .AVIATION...Coastal TAF sites began reporting MVFR CIGS this morning as a broad area of ST/SC expanded over land from the coast and the coastal plane. Large areas of MVFR/IFR Vis due to haze were also reported into afternoon at ACV, CEC and the Humboldt Bay Area. The main weather feature to expect is an approaching cold front that will pack more energy than recent weather disturbances. This stronger front will bring rain to CEC in the early evening; HREF guidance suggests things starting around 03z or maybe just a little sooner. Models are in agreement that this front will have a significant wind increase and wind shift as the front passes. Above ground "increasing north winds" may briefly introduce the threat of LLWS along the coast by mid-morning. Rain will convert to showers in the latter morning. /TA && .MARINE...A front is expected to pass through the coastal waters late tonight bringing fresh to strong northerly breezes. Otherwise, gentle to moderate northwest breezes should dominate throughout the week. A strong NW swell has peaked, but will continue throughout the coastal waters into late tomorrow night generally staying above 10 feet. Another NW swell will move through midweek, peaking at 11 to 12 feet. And yet another NW swell will move through later in the week, peaking around 8 feet. && .BEACH HAZARDS...A long-period northwest swell will continue to bring the potential for large breaking waves this afternoon and evening. Forecast breakers on area beaches should range from 16 to 21 feet and will result in larger than normal surf and possible beach erosion. A Beach Hazards Statement remains in effect through this evening. Beachgoers and mariners should continue to exercise extreme caution and stay vigilant if venturing near the ocean. && .EKA WATCHES/WARNINGS/ADVISORIES... CA... Beach Hazards Statement until 9 PM PDT this evening for CAZ101-103-104-109. Winter Weather Advisory from 5 AM to 5 PM PDT Tuesday for CAZ107. NORTHWEST CALIFORNIA COASTAL WATERS... Small Craft Advisory until 9 AM PDT Wednesday for PZZ450- 455-470-475. && $$ Visit us at Follow us on Facebook and Twitter at: For forecast zone information see the forecast zone map online:
Area Forecast Discussion
National Weather Service Grand Rapids MI
1056 PM EDT Mon Oct 31 2022 LATEST UPDATE... Update .UPDATE... Issued at 1056 PM EDT Mon Oct 31 2022 Main concern for the overnight is fog and specifically the potential for dense fog. At this point opting to hold off on a Dense Fog Advisory given the lack of 1/4 mile visibilities at the present time. Also, and maybe more importantly holding off due to the wind increase noted in the 18z models below 1,000 feet between 06z and 12z. Our thinking is the 10-20 knot winds developing in that shallow layer may be enough mixing to keep dense fog from forming and promote more of a stratus deck. Bottom line, not enough confidence at this point to issue an Advisory. && .DISCUSSION...(This evening through next Monday) Issued at 227 PM EDT Mon Oct 31 2022 - Risk for locally heavy showers this afternoon into early evening PWAT values are up around 200 percent of normal with a surface wave moving in from the southwest this evening. Forecast soundings are shown to be saturated through the mid levels...especially near and southeast of Grand Rapids. Radar trends show that where the showers are....they are not moving very quickly. Surface convergence is maximized where the showers are developing. Some instability has developed closer to the MI/IN border...which may try to pivot slightly north as the surface wave moves in. High res models have been showing showers increasing over the next couple of hours. They are also generating small areas of over a half inch of rain...which seems reasonable. A small risk for an isolated thunderstorm exists as well. It does look like the showers will persist into the early evening hours...especially southeast of Grand Rapids. During the evening the moisture depth does drop off steadily so that should eventually support a diminishing trend to the shower activity. - Dense fog risks into Wednesday morning Given the recent rain and potential for at least partially clearing will not take much cooling to generate more fog tonight. The HRRR has been showing this trend and it seems reasonable. Thus we included fog in the forecast for tonight...mentioned the hazard in the HWO and on social media. For Tuesday night...a better chance for clearing exists. The winds will still be light and low levels relatively moist. This may result in another period of fog that may impact the Wednesday morning commute. - Unseasonably warm weather for mid to the start of the weekend Deep southwest flow sets up for Wednesday into Friday. Even into Saturday...the surface cold frontal passage looking less likely for Friday. The temperature at 925 mb rises from around 13 deg C Wednesday to 14 deg C Thursday and 15 deg C Friday. Some near 70 degree max temperatures are looking possible. As a result we will be warming up the temperatures...especially Saturday due to the diminished chance for the frontal passage. With the wind expected to persist Thursday night we may not fall below the record high min temperatures for Friday. - Strong fall frontal passage over the weekend Several of the deterministic models(GFS and High Res Euro) are showing a stronger mid to upper level wave tracking in from the southwest later Saturday night with some indications of a possible fold in the Trop. The winds at 500 mb make a run at 115 to 120 knots based on the latest runs. Strong surface winds are starting to show up in the models with an increased risk for values topping 40 mph around the passage of this wave...later Saturday night into early Sunday morning. The ensemble wind gust forecasts from these models are also showing an increasing number of members with stronger wind gusts...especially the Jackson area. Much can change between now and when this potential system arrives...but we will need to monitor the trends closely in the coming days. && .AVIATION...(For the 00Z TAFS through 00Z Tuesday evening) Issued at 800 PM EDT Mon Oct 31 2022 Difficult aviation forecast tonight with wildly variable conditions at the onset. At 00z, conditions range from VFR at GRR and JXN but we also have below 2 mile visibility at LAN and ceilings as low as 100 feet at LWA. The trend tonight should be a deterioration of conditions with widespread LIFR ceilings once again at most TAF sites by 07z. A threat of widespread below 1 mile visibilities also exists. A slight increase in wind between 250 feet and 1,000 feet off the deck tonight may push conditions more towards a stratus deck vs widespread 1/4 mile fog. Both are possible though and we will be monitoring TAFs closely tonight. A rapid improvement in conditions should occur on Tuesday between 14z and 17z. VFR conditions are expected for Tuesday afternoon. Light and variable winds tonight will be southwest to west at 5-10 knots Tuesday afternoon. && .MARINE... Issued at 611 PM EDT Mon Oct 31 2022 We have issued a Marine Dense Fog Advisory for areas south of Grand Haven through the night. The advisory is valid until 10am on Tuesday morning. Dew points in the low to mid 50s combined with water temperatures around the same temperatures has resulted in dense fog. St. Joseph and South Haven webcams are currently showing fog and we expect a northward expansion this evening. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...None. LM...Dense Fog Advisory until 10 AM EDT Tuesday for LMZ844>846. && $$ UPDATE...Duke DISCUSSION...MJS AVIATION...Duke MARINE...Duke
Area Forecast Discussion
National Weather Service Lincoln IL
823 PM CDT Mon Oct 31 2022 .SYNOPSIS... Issued at 222 PM CDT Mon Oct 31 2022 Clearing skies and light winds will lead to fog development for parts of central and eastern Illinois tonight and Tuesday morning. Some of the fog could be dense. After the fog burns off Tuesday morning, mild and dry weather will dominate the region through midweek. && .UPDATE... Issued at 823 PM CDT Mon Oct 31 2022 Main challenge overnight will be with the fog concerns. Low cloud deck is roughly east of a Danville to Effingham line right now, and RAP low level RH plots would suggest it would be out of the area by midnight. 11-3.9 GOES fog satellite data is showing some rapid fog development this evening in areas from Bloomington to Shelbyville, where the clearing took place late and there wasn`t much time to dry out before sunset. This is not being handled well by the high-res guidance. Such guidance was focused more on the period after about 2-3 am with dense fog potential south of a Danville to Taylorville line. After coordinating with neighboring offices, a Dense Fog Advisory has been issued from about I-55 southeast through 10 am Tuesday. To the west of there, a drier atmosphere is noted (dew points low-mid 40s) and think there shouldn`t be as much of a fog issue outside of some of the river valleys. && .SHORT TERM...(This evening through Tuesday) ISSUED AT 222 PM CDT Mon Oct 31 2022 Latest water vapor imagery indicated the mid level shortwave was lifting northeast of the area into western Indiana. Trailing deformation zone rains have shown a marked decrease in coverage and intensity between the I-55 and I-72 corridors over the past couple hours. This trend will continue as the upper support departs, leaving just a few showers over the eastern half of the CWA into late afternoon. This will set the stage for decent Halloween evening conditions with clearing skies, light to calm wind and temperatures falling through the 50s (about 10 degrees warmer than last year). Overnight, winds remain calm and with mainly clear skies and damp ground from rain the past couple days, conditions will be favorable for fog development. High resolution guidance points to areas east of I-55 for more widespread coverage. Will add fog mention to grids but hold off on an advisory as confidence in dense fog is not high enough, but this may be added with later forecast updates. After morning fog dissipates, skies turn mostly sunny as upper level ridging quickly builds into the Midwest. By afternoon, 900 mb temps rise to the mid teens C, and will result in highs in the upper 60s to around 70 degrees. && .LONG TERM...(Wednesday through Monday) ISSUED AT 222 PM CDT Mon Oct 31 2022 A stretch of nice early November weather looks to dominate the area Wednesday into Friday as an upper level trough deepens over the western U.S., allowing downstream ridging to amplify over the Midwest. Little spread noted on temperatures from ensemble guidance, leading to high confidence of temperatures running 10-15 degrees above normal through the period. Southwest gradient flow increases Thursday and Friday, so light winds Wednesday will turn breezy for the end of the week. The main weather maker for the extended forecast is a deep cutoff low centered near the four corners early Friday, which opens and lifts northeast to the northern Great Lakes on Sunday. Ensemble guidance offers up timing differences which are typical with a closed low, which results in an extended period of PoPs from Friday into Sunday. However a majority of operational and ensemble runs sans the fastest Canadian/GEM, point to a wave of warm advection rains ahead of the cold front crossing the region late Saturday into early Sunday morning. The system appears fairly dynamic with the upper wave opening and taking on a negative tilt, along with strong wind fields aloft and a good surge of low level moisture. Current blended guidance shows no thunder probabilities but these may be added with later forecasts. Locally heavy rain also possible with some solutions showing over 1" QPF. Dry weather and seasonable temps look to move in behind this system for late Sunday into early next week. && .AVIATION...(For the 00Z TAFS through 00Z Tuesday evening) Issued at 626 PM CDT Mon Oct 31 2022 A bit of a challenging TAF forecast for this set. Last of the current IFR/LIFR conditions will be moving out of KDEC/KCMI over the next hour or two. However, conditions appear favorable for more fog to form later tonight, as skies clear and winds remain light. Latest HREF guidance from 18Z shows probability of LIFR conditions at KCMI around 50-70% by 12Z. However, more recent deterministic models favor areas a bit further south. Have included KDEC/KCMI with a period of 1/2SM visibility toward 12Z with a few hours of MVFR visibilities at the other sites. Once the fog lifts around mid morning, skies should be mostly clear the remainder of the forecast period. && .ILX WATCHES/WARNINGS/ADVISORIES... Dense Fog Advisory until 10 AM CDT Tuesday for ILZ038-042>046- 051>057-061>063-066>068-071>073. && $$ UPDATE...Geelhart SYNOPSIS...25 SHORT TERM...25 LONG TERM...25 AVIATION...Geelhart
Area Forecast Discussion
National Weather Service Memphis TN
929 PM CDT Mon Oct 31 2022 ...New UPDATE... .UPDATE... Issued at 922 PM CDT Mon Oct 31 2022 Short term guidance has been hinting at less areal coverage and intensity of fog overnight. This may be caused in part by dewpoints underperforming across the area. Dewpoint depressions around the TN Valley and north MS were forecast to be between 0 and 1 degree overnight, but latest obs and trends suggest DPDs closer to 3 or 4 degrees, which would hinder fog potential. Patchy dense fog could still certainly develop around 11 or 12Z, but it`s looking to be a little less widespread now. The HWO covers this well. && .DISCUSSION... (This evening through next Sunday) Issued at 242 PM CDT Mon Oct 31 2022 A split flow pattern will persist across much of the CONUS through midweek with the polar westerlies generally confined to the US-Canada border. One shortwave trough is lifting northeast across IL/IN while a second is moving through the Southern Plains. Strong southwesterly flow aloft will continue downstream of the positively-tilted trough axis with the Southern Plains trough eventually moving across the Mid-South late Tuesday into Wednesday. A few light showers (or sprinkles) continue this afternoon, mainly over West TN. Any lingering precipitation will end quickly by 00z and cloud cover will scatter out. Moist soil conditions, light winds, and clearing skies suggest the potential for fog tonight. Fog may be dense in some areas and may eventually require a Dense Fog Advisory. Otherwise, expect dry/warmer conditions the next few days with highs in the 70s and lows mainly in the 50s. Shortwave ridging will settle over the Lower MS Valley late Wednesday and Thursday, continuing the dry weather pattern. This ridge will attempt to build poleward through the Southeast into the Delmarva area late in the week. Meanwhile, a strong trough will dig over the western CONUS. This trough looks to bring inclement weather to the Mid-South over the weekend, but the aforementioned ridge over the east is expected to slow its eastward progress. Ensemble clusters indicate that the GEPS strongly favors a more progressive trough and weaker ridge, bringing precipitation into the CWA late Friday while the GEFS and, to a stronger degree, the EPS indicate stronger ridging over the southeast and a later arrival. Experience is leaning toward the latter (slower) solution. This system will lift northeast as it moves out of the Southern Plains and, like the past few systems, will quickly occlude as it crosses the Ozarks. Strong kinematics will accompany this cyclone with 40-50 kts of southerly flow at 850 mb and a meridional 125+ kt jet on its eastern flank. This will result in an uptick in wind speeds Saturday and Saturday night with breezy conditions anticipated over most of the area. This system will be filling as it pulls away from the area, but the main question will be the quality of the instability in the warm sector. The 12z ensemble data maintains only very low probability for CAPE greater 500 J/kg. This system bears watching, but the signal for any significant weather appears muted at this time. MJ && .AVIATION... (00Z TAFS) Issued at 630 PM CDT Mon Oct 31 2022 Main concern is fog formation overnight. Surface dewpoints were running around 7 degrees F higher over middle TN where a solid FL060 deck prevailed. This deck should clear near the TN RIver later this evening, with fog likely likely developing along the TN River and adjacent river valleys to the west. HREF, NBM shortblend and HRRR depict greatest potential for LIFR at TUP, but the MKL TAF is carrying an earlier onset hedge against guidance, due to proxmity to the TN River and overall climatology. Given the calm surface winds and weakening westerly flow off the deck, urban heat island will likely delay and partially alleviate IFR fog potential after 10Z. PWB && .MEG WATCHES/WARNINGS/ADVISORIES... AR...None. MO...None. MS...None. TN...None. && $$ PUBLIC FORECAST...MJ AVIATION...PWB
Area Forecast Discussion
National Weather Service Melbourne FL
906 PM EDT Mon Oct 31 2022 ...New UPDATE, MARINE, AVIATION, HYDROLOGY... .UPDATE... Issued at 843 PM EDT Mon Oct 31 2022 Earlier shower and storm activity has diminished over land areas by 9pm. However, a few showers continue to linger over the Atlantic waters. Shower chances will persist here overnight and an isolated storm cannot be ruled out well offshore. With clearing skies, the main story tonight will be the potential for patchy fog. The HRRR has taken the idea and ran with it, blanketing a majority of the area by daybreak. Other mesoscale models and LAV guidance are a bit more spatially conservative, so have hedged closer to their solutions. Nonetheless, patchy fog is expected from around southern Brevard and Osceola Counties northward, especially along and north of the I-4 corridor. Fog may become dense at times, with visibilities falling below 1 mile and even to around 1/4 mile in some locations. Motorists should be prepared for the potential for rapidly changing visibilities. If encountering dense fog, reduce your speed, use only your low beam headlights, and leave extra distance between your vehicle and the one in front of you. Any fog that forms will begin to diminish around sunrise, clearing through the morning hours. Overnight lows in the upper 60s to low 70s, with light winds. && .MARINE... Issued at 843 PM EDT Mon Oct 31 2022 Generally favorable boating conditions persisting, although showers will remain possible across the Atlantic waters overnight. SE winds becoming S towards daybreak, then N/NE into Tuesday afternoon. Wind speeds remaining around 10-12kts or less. Seas 3-5ft. && .AVIATION... (00Z TAFS) Issued at 843 PM EDT Mon Oct 31 2022 Patchy fog is expected overnight tonight across much of the area from around southern Brevard and Osceola Counties northward. Fog may become dense at times, with TEMPOs included for IFR/LIFR VIS from KISM/KMCO/KTIX northward, beginning by around 8Z at KDAB and KSFB. More minor VIS reductions may be possible for the more southern coastal terminals. However, VIS should remain VFR/high end MVFR at these locations. Otherwise, VFR conditions prevailing, with light winds becoming E/NE at less than 10kts Tuesday afternoon. A few showers will be possible during the daytime hours, but coverage is expected to remain low enough to negate a VCSH mention at this time. && .HYDROLOGY... Issued at 843 PM EDT Mon Oct 31 2022 The St. Johns river at Astor will remain in Moderate Flood Stage for the foreseeable future. The river is currently around 3.7 feet and is expected to slowly decline through this week. Near Deland, the river will remain in Moderate Flood Stage as it continues a very slow decline this week. Near Sanford, the river will remain in Moderate Flood Stage through mid week then is forecast to fall into minor flood stage late this week. The river is currently at 7.1 feet and will continue a slow decline. At Geneva above Lake Harney, the river will remain in Moderate Flood Stage for the foreseeable future. The river is currently at 9.7 feet and will continue a very slow decline. && .PRELIMINARY POINT TEMPS/POPS... DAB 69 85 69 83 / 10 10 10 30 MCO 71 88 71 87 / 10 20 10 30 MLB 71 85 71 84 / 20 20 10 30 VRB 70 87 71 85 / 20 20 10 40 LEE 69 87 70 85 / 10 10 10 30 SFB 71 87 70 84 / 10 10 10 30 ORL 72 88 72 87 / 10 20 10 30 FPR 70 86 70 84 / 20 20 10 40 && .MLB WATCHES/WARNINGS/ADVISORIES... FL...None. AM...None. && $$ Leahy/Sedlock
Previous forecast discussion...
As of 230 PM EDT Monday...
Showers ending from west to east this evening. Broad area of lift associated with occluded front emanating from a decaying cutoff low over the Ohio Valley will gradually move north and east of the area this evening. This will allow ongoing shower activity to come to an end. Elevated CAPE, on the order of 200-600 J/KG has been supporting some of the embedded heavier downpours, but I have yet to see any in-cloud lightning. As such, have refrained from adding any thunder to the gridded forecast...and will leave it out unless trends suggest otherwise. In spite of the rain coming to an end this evening, clouds and areas of fog will likely persist overnight. It may take until after daybreak Tuesday to get bonafide clearing associated with deeper mixing in the wake of the current disturbance. Aside from the airmass being rain cooled, temperatures are expected to be above normal normal with respect overnight lows tonight...lows between about 48-55 degrees...a full 10 degrees above normal. This will set the stage for a warm day Tuesday once the sun comes out with highs in the 60s/70s...or 5 to 10 degrees above normal. && .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY NIGHT/... As of 120 PM EDT Monday... Surface high pressure builds in Tuesday night, but will quickly be covered by a closed upper level low by Wednesday. With no return flow from the Gulf, this low may only cover the area with mid and high clouds while keeping temperatures close to normal. But still, with some heating under the cold pool, a stray light mountain shower or sprinkle is possible Wednesday afternoon. This low will slide off the Carolina coast Wednesday night. Cool high pressure will then wedge south into the region on Thursday. More sun is expected Thursday but northeasterly flow should keep temperatures near normal for another day. && .LONG TERM /FRIDAY THROUGH MONDAY/... As of 135 PM EDT Monday... Surface high pressure will remain wedged over the area into next weekend. Meanwhile, heights will increase aloft with an upper level ridge becoming centered over the region over the weekend. With abundant dry air and sunshine, afternoon temperatures will warm to around 10F warmer than normal despite there being a wedge in place. Rain chances begin to increase early next week as a cold front approaches the region from the west. && .AVIATION /02Z TUESDAY THROUGH SATURDAY/... As of 220 PM EDT Monday... Poor flight conditions tonight... Low ceilings and fog have arrived behind the rain this evening. This will continue to be an issue overnight. Likely ceilings and visibilities will flip flop overnight, with low ceilings being the dominating impact on flight conditions, but brief windows of low visibilities also occuring. Conditions are expected to quickly improve in the morning for most sites. However, weak upslope flow will keep low clouds in the west for a good portion of the day Tuesday. Forecast confidence is average. Extended Aviation Discussion... A weak disturbance may bring some mid/upper level clouds for Wednesday...producing virga, but little or no surface precip expected. Aside for this disturbance, expect VFR conditions Wednesday through Saturday with above normal temperatures. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...None. NC...None. WV...None. && $$ SYNOPSIS...PM NEAR TERM...DS/PM/RR SHORT TERM...RCS LONG TERM...RCS AVIATION...PM/RR