Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 01/10/22


Area Forecast Discussion
National Weather Service Binghamton NY
741 PM EST Sun Jan 9 2022 .SYNOPSIS... A cold front will sweep through the area tonight, with lake effect snow into the New York Thruway tonight lifting north into Monday. The lake effect snow will push southward Monday night, ahead of a cold front which will bring bitter cold to the entire region Monday night through Tuesday. High pressure then builds into the area for the middle of the week. && .NEAR TERM /THROUGH MONDAY NIGHT/... 741 PM update... No major changes made to the forecast this evening. Lingering light rain showers moving out of the area changing to snow into the Catskills. Then, another cold punch of air arrives along a cold front tonight with more lake effect snow showers moving in from the northwest. Lake Effect Warnings and Advisories...and Wind Chill headlines remain unchanged. 430 PM Update... Weak but complex weather system is shifting east of the area this evening. Strong jet streak remains over SW Ontario, leaving most of our area in the right entrance region with a broad area of upper level divergence, while a weak prefrontal vort max is rolling into the area. Both are helping cause a slight uptick in precip coverage again, mainly northwest of the I-88/I-86 corridor in NY State, but some light precip is also noted over the Poconos and Catskills. RAP soundings suggest the latter area is likely drizzle and freezing drizzle, while ice crystals are more likely present farther north and west (the warm nose is pretty much gone at this point). Temperatures are mostly above freezing except in a few pockets across the Susquehanna headwaters and the Cats/Poconos, but ground temperatures likely remain below freezing in a few spots. While any additional ice accumulation is likely to be minimal, some slick spots could persist over the next hour or two. Issued an SPS to cover this as the bulk of the event and impacts are over. The the area NW of I-88/86, soundings are more likely to contain ice crystals, so precip type will be rain or snow. Temperatures will slowly start dropping from west to east over the next couple of hours, then drop quickly behind an approaching cold front which appears to be approaching the north shore of Lake Ontario now. High res models suggest the cold front/wind shift could be accompanied by some squally snow rain/snow showers, followed by a lake effect band setting up along the Thruway this evening (roughly after 8 PM) before drifting north overnight. The band looks to be quite persistent north of the Thruway tonight, focused over Oneida County. Some weak instability may cause the band to become a little less organized during the day Monday, especially further away from the Lake, and the focus of the showers may tend to favor the west slopes of the Tug Hill for a time. The band will become better organized again during the late afternoon and early evening hours, with snowfall rates likely increasing as the DGZ lowers ahead of a stronger shortwave trough and associated secondary cold front. Monday night will be tricky as the shortwave and secondary front will cause winds to shift to the northwest. The lake effect band will likely get pushed south and weaken, but models often handle this transition poorly. Late Monday night, northwesterly bands will likely set up, favoring Onondaga/Cortland and Seneca/Tompkins Counties, though snowfall will likely be much narrower and generally lighter. Again, QPF and snowfall forecasting is difficult with this scenario, and would not be surprised to see isolated advisory-level snowfall amounts Monday night south and west of Syracuse. Storm Total Snowfall eased up a little on amounts in southern and eastern Oneida County with the lull expected during the day tomorrow. Jackpot will likely be in the far northwest corner which clips the west slopes of the Tug Hill, where 15 to 20 inches is expected. Lighter amounts are expected further south and east. Northern Onondaga and northern Madison Counties will see 3 to 6 inches overnight before the band drifts northward, with additional snowfall Monday night, and a significant break in between. Snowfall amounts don`t quite make warning criteria over a 12 hour period, however. Late Monday night may end up seeing advisories spread further south and west into the Finger Lakes, but there is still too much uncertainty for now. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY/... A Wind Chill Advisory and a Wind Chill Warning have been issued for Monday night through early Tuesday morning. With a bitter airmass in place as 850mb temperatures drop to as low as -20 to -25C late Monday night, temperatures will start off in the single digits above and below zero Tuesday morning, with values in the teens below zero in northern Oneida county. Even though winds will gradually be dropping back by the early hours of Tuesday, bitter temperatures will still yield wind chills as low as - 15 to -25F. Temperatures will not improve much during the day, only peaking in the single digits across northern Oneida county and the higher terrain of the Catskills, and in the teens across most of the rest of the area. Otherwise, expect lingering lake effect snow showers mainly across the Finger Lakes, with light accumulations below an inch possible. Snow showers wrap up into the late afternoon and evening as high pressure builds in, soundings dry up, and flow starts to shift more west/southwesterly. Dry weather continues overnight through Wednesday with high pressure in control. A few high clouds may move through central NY as a shortwave tracks into southern Ontario and Quebec, but this will not be enough to keep temperatures from plummeting once again. Expect lows in the single digits once again. Temperatures Wednesday afternoon will climb much higher than on the previous day as warmer air advects in on the backside of the ridge. Expect highs to range in the 30s under partly sunny skies. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... On and off chances for snow showers will return for the rest of the work week and into the weekend. First, another trough and weak cold front moves through late Wednesday night to early Thursday. Model soundings are still quite dry with this, so we may struggle to see a great deal of snow accumulations and most of the area may be able to stay dry. Some lake effect snow showers persist through the rest of Thursday and Thursday night southeast of Lake Ontario. Ridging into Friday will bring about another dry day with more sunshine, followed up by additional chances for snow into Saturday. While the exact location is uncertain, models are generally agreeing on a trough digging into the central US, and a surface low closing off over either the Great Lakes (as in the GFS) or the lower Midwest (Euro). Given that these discrepancies exist, PoP has been limited to just a chance. Otherwise, temperatures will be more seasonal for the remainder of the forecast period. Thursday will be the warmest with highs in the 30s and overnight lows in the 20s, followed up by cooler air behind the cold front Friday into the weekend. && .AVIATION /01Z MONDAY THROUGH FRIDAY/... A batch of rain showers is currently moving across the area as surface temperatures are above freezing across all terminals. Temps will fall through the evening and rain showers will change to snow. MVFR and IFR ceilings are expected to hold for the into the early overnight hours evening, lifting to low-end VFR at most terminals between 04-06z. The exceptions will be at KRME and KSYR. Heavy lake effect snow develops late this evening, causing visibility to LIFR at SYR and IFR at RME for much of the night. Snow becomes less intense at KSYR after 06Z as the begins to lift northward. A slow return to VFR will take place, with a chance for a stray snow shower to drop conditions to MVFR for a brief period until 10Z. KRME, however, will remain under IFR restrictions until the band continues to move northward out of the area towards the early morning. Winds turning to the west/northwest into the evening remain strong through the night, gusting up to 25-30kts. Winds slowly weaken through Monday morning, but gusts 18-24kts can be expected across the area. and afternoon. Outlook... Monday night through Tuesday morning...Occasional restrictions at NY terminals due to lake effect snow showers, especially KSYR-KITH-KBGM. Gusty NW winds and bitter cold Tuesday morning may impact ground operations as temperatures dip into the single digits, with lows well below zero at KRME. Tuesday afternoon through Tuesday night...Mainly VFR with chance for linger lake effect snow at SYR. Otherwise bitter cold temperatures once again with most terminals in single digits Tuesday night. Wednesday...Mainly VFR. Wednesday night through Thursday...Disturbance with chance of snow showers and associated restrictions. Friday...Mainly VFR. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...Wind Chill Advisory from 1 AM to 10 AM EST Tuesday for PAZ039- 040. NY...Wind Chill Advisory from 1 AM to 10 AM EST Tuesday for NYZ017- 018-025-036-044>046-055>057-062. Wind Chill Warning from 1 AM to 10 AM EST Tuesday for NYZ009- 037. Lake Effect Snow Warning until 1 AM EST Tuesday for NYZ009-037. Winter Weather Advisory until 1 AM EST Tuesday for NYZ018-036. && $$ SYNOPSIS...MPH NEAR TERM...BJT/MPH SHORT TERM...HLC LONG TERM...HLC AVIATION...HLC/JTC
Area Forecast Discussion...UPDATED
National Weather Service Brownsville TX
600 PM CST Sun Jan 9 2022 .DISCUSSION...Updated for latest aviation discussion below. && .AVIATION...A cold front, currently extending south of BKS to east of APY, will continue to push through Deep South Texas this evening. Brownsville radar indicates some convection developing ahead and along of this boundary. Will continue to mention VCTS/TSRA at all Rio Grande Valley aerodromes through late this evening. A mix of VFR/MVFR/IFR conditions can be expected through late this evening with convection. Low- level, MVFR, stratus clouds will develop behind the front and persist through the night and into Monday. Northerly winds will become gusty, with gusts between 20-25 knots tonight and into Monday morning. MVFR/IFR ceilings will prevail through the rest of the period. && .PREV DISCUSSION... /issued 223 PM CST Sun Jan 9 2022/ SHORT TERM (Now through Monday Night): The overall short-term forecast remains on track, with a moderate-strong cold front anticipated to push north-to-south through the CWA beginning late this afternoon. KBRO doppler radar currently shows isolated light to moderate, popcorn-type, showers starting to develop offshore and along the coast, with isolated thunderstorms developing up the coast near Corpus Christi. Isolated/spotty showers will continue before the better chances of precip. unfolds with the front this evening. Latest forecast models and mesoanalysis continues to indicate an unstable atmosphere ahead of the approaching front. MLCAPE values between 1500-2500 J/kg will be more than enough energy to see scattered to numerous showers and thunderstorms just ahead of and along the frontal boundary. Latest run of the HRRR model keeps the bulk of the heaviest rainfall east of US-281/I-69C beginning late this afternoon. The front will exit the area by or even before midnight tonight, but shower activity may linger through the morning on Monday, especially across the lower RGV and immediate coastline as a weak coastal trough forms. As far as rainfall amounts, general values between 0.25-0.50" can be expected (maybe less across western counties). However, values over an inch are not out of question, especially where the heavier showers/storms occur. Widespread flooding is not anticipated at this time, but localized ponding of water and minor flooding in low-lying areas are possible in spots. Temperatures behind the front will drop into the mid-upper 40s and lower 50s overnight tonight under cloudy skies. An abundance of overrunning will cause cloud cover to stick around during the day on Monday, which will keep daytime temperature on the cool side; temps will likely struggle to get out of the 50s. Also, northerly winds are expected to stay fairly breezy behind the front on Monday, which may make temperatures feel a few degrees cooler. Skies will remain mostly cloudy on Monday night, which should keep temperatures contained in the 40s (lower 40s north, upper 40s south). LONG TERM (Tuesday through Sunday): High pressure over East Texas will continue to shift east but the southward extension will remain over the CWA. A weak surface coastal trough may still be evident to the east over the Gulf. A mid-level shortwave trough will swing west to east across North Texas on Tuesday and will then track over the north Gulf on Wednesday. We may see enhanced shower activity over the adjacent Gulf on Wednesday as the base of the trough extends out over the Northwest Gulf. With high pressure still to the north, winds will retain a north to northeast fetch out into the mid-week. From mid to late week mid-level ridging will build just upstream over the High Plains, shifting slowly east. High pressure will unlock from the Great Basin and the Northwest on Friday as a vigorous short wave dives south from Central Canada. A short wave kicking out from a Baja low will synch up behind the surface front to push it through late Saturday. This scenario is in line with the inherited forecast reasoning. The front will be knocking at the door Saturday afternoon, and there will be some capping of high temps out west, based on guidance numbers coming in from Laredo. Overrunning and rainy gray, cooler weather will take over Saturday night across the CWA and into Sunday. While temps will warm several degrees above average mid to late week, the Saturday front will cool things to below average next Sunday. A follow-on weak shortwave trough, and this is handled slightly differently by the GFS and ECMWF, moving overhead Monday will keep rain chances going, but surface high pressure will shift rapidly east as well, with a residual coastal trough offshore to keep marine and coastal rain chances alive early the following week. MARINE: Now through Monday Night...Small craft will need to continue to exercise caution on the offshore Gulf waters through the afternoon as wave heights continue to remain agitated around 6 feet. Marine conditions will then quickly deteriorate beginning early this evening as a moderate-strong cold front pushes over the coastal waters. A Small Craft Advisory goes into effect for all of the coastal waters beginning at 6 PM this evening through at least 6 PM Monday evening, with the possibility of an extension into Monday night/Tuesday morning. Northerly winds will drastically increase and become gusty behind the front, with a few gusts up to gale force tonight and through Monday morning. In response to the winds, seas on the Gulf will increase between 6 and 9 feet, occasionally higher on the offshore waters. A gradual improvement of winds and seas will begin Monday afternoon, but conditions will likely remain hazardous through Monday night. Tuesday through Friday Night...North to northeast winds will start out moderate to fresh on Tuesday with elevated seas and possible small craft advisory conditions on the Gulf. After Tuesday, light to moderate north to northeast winds and moderate seas will persist through about Thursday. Winds will turn to southeast and south late in the week. Seas will also diminish to low or moderate. && .PRELIMINARY POINT TEMPS/POPS... BAYVIEW/PORT ISABEL 50 60 51 68 / 80 40 10 0 BROWNSVILLE 51 58 49 68 / 80 30 20 10 HARLINGEN 48 57 47 66 / 80 30 10 0 MCALLEN 50 57 47 65 / 80 20 0 0 RIO GRANDE CITY 49 59 46 65 / 50 10 0 0 SOUTH PADRE ISLAND 57 61 57 66 / 80 40 20 10 && .BRO WATCHES/WARNINGS/ADVISORIES... TX...None. GM...Small Craft Advisory until 6 PM CST Monday for GMZ130-132-135- 150-155-170-175. && $$ This product is also available on the web at: https://weather.gov/rgv 63-KC/AVIATION
Area Forecast Discussion
National Weather Service Grand Rapids MI
702 PM EST Sun Jan 9 2022 LATEST UPDATE... Aviation .DISCUSSION...(This evening through next Sunday) Issued at 300 PM EST Sun Jan 9 2022 - Cold with lake effect snow showers into Monday night The coldest air of the winter so far is surging into our area this evening. This is be the big story for the next 36 hours, how cold it will be. Wind chills will mostly be in the 0F to -10F range into Tuesday morning. Lows tonight will be between 0F and 10F above and tomorrow we have secondary surge of even colder air coming in during the afternoon. That will limit our high temperature to the mid teens. We can thank a nearly 1040 mb high that has come from Northwest Canada for this cold period. As for snow with this cold outbreak, the moisture is very shallow based on model soundings, mostly under 4000 ft into Monday morning. Even so the DGZ is in or below the clouds so light snow showers are expected (since they are happening now). The passage of that secondary cold front, brings in the -20c 850 temps by midday Monday. Based on the HRRR and NAM 3km, this sets the stage for inversion heights between 5000 ft and 6000 ft. this will be enough to generate stronger snow showers that will likely result in some light accumulations, maybe an inch or two. Being a Northwest flow event the largest snowfall totals will be south and west of Grand Rapids. Since the polar jet core does not get east of us until Tuesday morning the snow showers will continue until then. - Warming some and little precipitation till next weekend The next system from the Pacific wave train to impact our weather is currently near the International Date Line. It builds a ridge out in front of it. That in turn pushes the upper trough over us to our east by Wednesday. The next shortwave crosses the Canadian Rockies late Tuesday into Wednesday and pulls down more Canadian Polar air into the northern Plains. However that system from the Dateline has to short of a wavelength to allow that next push of cold air to really get here. We have to wait till next weekend for that system to get far enough east to allow a larger trough over the eastern CONUS, which brings the cold air back. This next system coming across the CONUS has the potential to bring us a significant snow event toward next weekend. About 20 of the 80 ensemble members of the GFS and ECMWF do just that. Of course that means 60 of the 80 do not. On the other hand only 30 of the 80 have no snow for us next weekend. The bottom line is snow event toward next weekend is possible. - Cold comes back third week of January The models suggest (CPC 8 to 14 day forecast says this too) that next week will be more persistently cold than this week. Most of the ensembles of the GFS, ECMWF and Canadian support this idea. The ensemble mean daily highs are below 26 degrees from Friday through Sunday the 23rd. Curiously the last 5 days of that period is the coldest with highs mostly near 20. && .AVIATION...(For the 00Z TAFS through 00Z Monday evening) Issued at 702 PM EST Sun Jan 9 2022 MVFR cigs - impacting mainly just MKG/AZO/BTL this evening - are expected to become more numerous overnight into Monday. Generally just flurries occurring from these clouds at times with little or no restriction to vsbys, however 3-5 mile vsbys probably becoming more common Monday as snow shower intensity/coverage increases somewhat. Brisk west-northwest winds of 10 to 20 kts with gusts around 25 kts continuing tonight and Monday. && .MARINE... Issued at 300 PM EST Sun Jan 9 2022 We are still getting gales at our near shore weather stations so we will keep our gale warning until 4 pm, then let is expire in favor of a small craft advisory that will continue into Monday evening. As we have been seeing the winds let up for about 12 hours then near gales come back by late Tuesday afternoon with the next surge of warm air. && .HYDROLOGY... Issued at 1100 AM EST Sun Jan 9 2022 While we are starting to see ice build up ice on area rivers, streams, lakes and ponds, it does not appear likely we will see any significantly impactful ice jam flooding this week. That is not to say some of the low areas on our rivers or places were there is a sharp bend in the river, we will not get a little flooding, that is very typical when our rivers start to freeze. Ice formation on area rivers really increases on days with highs near or below 20 degrees. We will see that tomorrow but it will only last one day as Tuesday will be warmer. However a significant pattern change seems likely by early next week (20th). We could have days in a row with highs below 20. That would really increase the ice on our rivers. We will have to monitor this closely. the rivers. At this point river levels are on the low side so any ice buildup will likely not result in && .GRR WATCHES/WARNINGS/ADVISORIES... MI...None. LM...Small Craft Advisory until 7 PM EST Monday for LMZ844>849. && $$ DISCUSSION...WDM AVIATION...Meade HYDROLOGY...WDM MARINE...WDM
Area Forecast Discussion
National Weather Service Wilmington NC
706 PM EST Sun Jan 9 2022 .SYNOPSIS... A strong cold front will bring rain late tonight, tapering off before sunrise Monday morning. From there, some of the coldest air that we have seen so far this season will start to settle in, with dry high pressure ruling the forecast through at least the middle of the work-week. Temperatures bottom out Tue into Wed, with some recovery likely as the latter part of the work-week progresses. && .UPDATE... Some tweaking to evening cloud cover and hrly temps/dewpoints based on latest Sat imagery, sfc obs and HRRR model trends. Current POP trend associated with the CFP tonight looking aok. Will take another look at thunder possibility at next update but instability in question especially with marine layer under 180-190 degree sfc winds ahead of the front pushing or having pushed inland. Sfc Dewpoint recovery to and/or above 60 looking quite limited which may hamper sea fog development given SSTS in the 50s to around 60. Current SCA time-line looking aok with main SCA coming from the post frontal Northerly winds due to a tightened sfc pg combined with excellent CAA. && .NEAR TERM /THROUGH MONDAY/... Latest surface analysis shows strong high pressure well offshore, which has provided plenty of return flow to set up across the area, allowing some areas closer to the coast to reach the lower 70s this afternoon. Meanwhile, a cold front currently near Appalachia will race towards the coast, emerging offshore by Monday morning. Showers currently over parts of the Deep South will continue to move in a west to east fashion. The western portions of our area should start to see rain around 02-03Z this evening, while the coast could see it around 05-06Z late tonight. Very little instability here, with the main dynamics of this system well to the north. However, there might be just enough unstable air to allow a rumble of thunder or two as the rain moves through tonight. Showers push offshore before sunrise Monday morning, with clouds starting to clear out later in the AM hours. Rainfall amounts generally linger between half an inch to three-quarters of an inch. This front brings some of the coldest air we`ve seen so far this season. Expecting non-diurnal trends with this system, meaning Monday`s high temperatures will likely be recorded not long after the calendar shifts from Sunday to Monday. From there, temperatures start to dip, as very cold high pressure starts to creep in from the upper Midwest. Expect breezy northerly winds by Monday afternoon, with temperatures in the mid-to-upper 40s. && .SHORT TERM /MONDAY NIGHT THROUGH TUESDAY NIGHT/... For the first time in a while, it will feel like winter has arrived as a cold front associated with a strong upper-level low over Newfoundland will be offshore. The 850 mb temperature will dip to -4C Monday night and -6C Tuesday night. We will see the coldest temperatures since November and for the winter. Low temperatures Monday are expected to fall to the middle 20s away from the beaches and around 30 at the beach strand. Low`s Tuesday will be from the lower 20s west of I-95 and mid to upper 20s at the coast. Highs on Tuesday will only reach the lower to mid-40s. No precipitation is expected during this time. && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... The large scale pattern shows two disturbances in the upper-level flow One will pass across the region late Wednesday night, and the second one will be approaching the east coast by later Saturday. The first system indicates low confidence as the GFS develops a low pressure center farther south and earlier than the ECMWF. The Ensemble members hint the low formation will be farther east and farther north than the deterministic run of the GFS. The NBM shows low PoP values over the coastal counties and the coastal waters. Temperatures along the coast are expected to be upper 30 to lower than the 40s. So will keep showers in the forecast for now. Again the 2nd system is a low confidence solution and will continue with a 20-30% chance of showers on Saturday. && .AVIATION /00Z MONDAY THROUGH FRIDAY/... VFR to start this period, will quickly be followed with periods of MVFR from ceilings and/or scattered showers ahead of an approaching cold front thru mid-evening. Instability in question for the threat of thunder this evening given latest model soundings. Will just mention it`s possibility here. After the CFP, the threat for widespread MVFR/IFR will occur from mainly ceilings and reduced vsby from light to moderate rain and/or fog. Progressive flow at all levels will push the wx conditions producing the flight restrictions off the Carolina Coasts by sunrise Mon. The upper trof axis will will swing off the Carolina Coasts midday Mon followed by drier air thru the atm column there-after. Any leftover VFR type stratocu will scour out by mid to late Mon aftn leaving SKC. Southerly winds 10g15 kt ahead of the cold front will veer to the W-NW 10g20kt after it`s passage. Winds further veer by Mon daybreak to Northerly at generally 10-15 kt with gusts up to 25 kt at times as a tightened sfc pg and excellent CAA combine. The gustiness in the wind field will diminish by sunset Mon. Extended Outlook...VFR through Wed night with high pressure dominating. Periodic MVFR associated with a CFP Thu thru Thu night. VFR Fri. && .MARINE... Through Monday...Strong cold front is quickly approaching the waters, which will allow for a considerable uptick in winds tonight. This easily gets us into Small Craft Advisory territory, valid from 10 PM Sunday through 5 PM Monday. Winds are currently southwesterly ahead of the front, transitioning to westerly and then north-northwesterly by the time the front pushes offshore by Monday morning. Seas currently 2-3ft across all waters, but will rapidly increase to 2-3ft at the coast and 5-6ft out 20nm from shore by late Monday morning. Monday Night through Friday...The cold front will be well offshore, and the offshore winds will be around 15 knots and will weaken into Tuesday. Seas will range from 2 to4 feet with the offshore flow. The low-pressure area is expected to develop well off the coast, and the winds are expected to be mainly offshore at or below 15 knots. On Friday, the biggest seas are expected with 2 to 5 feet seas. The higher seas are expected 10-20 miles off the coast north of Little River. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...None. NC...None. MARINE...Small Craft Advisory from 10 PM this evening to 5 PM EST Monday for AMZ250-252-254-256. && $$ SYNOPSIS...DCH/IGB UPDATE...DCH NEAR TERM...IGB SHORT TERM...RH LONG TERM...RH AVIATION...DCH MARINE...IGB/RH
Area Forecast Discussion
National Weather Service Miami FL
810 PM EST Sun Jan 9 2022 .UPDATE... Latest analysis this evening shows little evidence of the remnant frontal boundary over South Florida except for a diffuse band of clouds extending W from the Bahamas across the area. The 00z soundings from Miami and Key West show some slight low level drying compared to 12 hours ago, and a result shower activity has diminished over the area this evening. The factors above would suggest a rather quiet night upcoming...however there are a couple of signs indicating that precip may increase in coverage and intensity tonight. One of these is a mid/upper level shortwave trough near the Yucatan Channel and far SE Gulf of Mexico moving NE. Another is the presence of warm air advection, slight moisture convergence, and leftover frontogenesis over SE Florida according to SPC mesoscale analysis charts. Model guidance isn`t too consistent in depicting increasing rain tonight, with the HRRR the most aggressive with convection across SE Florida. Given the adequate forcing from the approaching mid/upper shortwave and modest low level forcing, global models such as the GFS and ECMWF and their respective MOS guidance seem to support the idea of rain coverage increasing. As a result, the higher PoPs tonight in the 50% range from Miami to the Palm Beaches look good, along with the possibility of a couple of thunderstorms. Locally heavy rain is a possibility, although the threat is highly conditional at this time. Rest of the forecast also looks on track. && .PREV DISCUSSION... (Issued 633 PM EST Sun Jan 9 2022) AVIATION(00Z TAFS)... Prevailing ceilings around 035-050 throughout most of the period, with perhaps a lifting of ceilings above 120 after 14z. Although not mentioned in the TAFs, there will probably be brief MVFR conditions in SHRA, especially east coast terminals, although not numerous enough to put in forecast and will let updates handle any short term changes. VCTS at KPBI after 13z, and elsewhere east coast after 18z. Mainly dry at KAPF. Wind decreasing E-SE to less than 10 knots. PREV DISCUSSION... (Issued 258 PM EST Sun Jan 9 2022) SHORT TERM (Now through Monday)... Building high pressure has kept the flow over South Florida easterly today bringing breezy conditions and abundant low-level moisture across the region. As this high propagates eastward, the pressure gradient over South Florida will weaken resulting in weaker winds for this afternoon and evening. The story with precipitation this afternoon is not too dissimilar than Saturday. PWAT values are still within the 90th percentile for this time of year across southern portions of mainland South Florida. The high building aloft is helping to limit instability some so overall the threat for thunder is a bit lower this afternoon, but still not completely zero, especially over south Miami-Dade. CAMs are showing some activity this evening along a developing Gulf Breeze (with a gradually weakening easterly flow) along Coastal Collier County. A few showers and perhaps a rumble of thunder or two will be possible in the strongest activity. Meanwhile, along the Atlantic, weak showers will likely continue into the evening hours. Tonight, CAMs are signaling some nocturnal convective activity to develop along the Atlantic coast with the localized baroclinic zone between land and Gulf stream. However, guidance differ a bit in terms of strength and overall coverage. As we move into Monday a cold front will be moving down the Florida peninsula. Another day of unsettled weather with showers and a few embedded thunderstorms possible. Storms will be possible particularly in the afternoon hours as the front gets a little closer in the vicinity of South Florida combined with diurnal heating. Temperatures will remain above average with the warmest conditions along the southwest coast and interior. LONG TERM (Monday Night through Sunday)... The cold front will be slow to move through the region on Monday night into Tuesday morning. This front will pretty much stall out just to the south of the region, which will help to keep the chances of showers in place throughout most of the day on Tuesday especially across the eastern half of South Florida. There will still be just enough instability in place to support a slight chance of thunderstorms through Monday night right out ahead of the front. Behind the front, the pressure gradient will once again tighten between the front to the south and an area of high pressure centered off to the north. This will allow for a breezy northeasterly flow to set up for the rest of the day on Tuesday and into Wednesday as well. Cooler temperatures will move in through the middle of the week as high temperatures range from the lower 70s across the Lake Okeechobee region to the upper 70s across Southwestern Florida. The uncertainty in the forecast increases later on Wednesday and into Wednesday night as models show a complex pattern trying to develop. The GFS depicts an incoming mid level trough from the southern Plains and phases it with a northern stream trough digging down into the eastern portion of the country. This solution allows for an area of low pressure to develop over the eastern Gulf of Mexico and moves it across Central Florida on Wednesday night bringing a secondary cold front through South Florida into Thursday morning. This solution would increase chances of showers and thunderstorms on Wednesday night into Thursday morning before bringing drier air in for the end of the week. The GFS is the most bullish out of the rest of the models and the ECMWF does not show this phasing of the northern and southern stream systems. The ECMWF does not develop this area of low pressure over the Gulf, however, it does bring a weaker secondary cold front through on Wednesday night into Thursday. The latest forecast shows a blend of the models, introducing a chance of showers on Wednesday night into Thursday across the region. This will continue to be monitored as the week progresses. In any event, a drier and cooler air mass will move into the region later on Thursday and into Friday as cold air advection takes place with high pressure building in from the north. Low temperatures on Friday and Saturday morning could be on the chilly side as they have the potential to drop into the mid 40s across Glades and Hendry counties and into the lower to mid 50s across the east coast metro areas. High temperatures towards the end of the week will generally remain in the lower 70s across most of South Florida. AVIATION(18Z TAFS)... Primarily VFR conditions prevailing with MVFR conditions possible in passing showers. Easterly winds 10-15kts gusting 20-25kts along the eastern terminals this afternoon. Later this evening weakening easterly winds to 10-15kts with showers still possible. Possible Gulf sea breeze development for APF today and tomorrow but it was left out of the TAF for today due to low confidence. MARINE... As a strong surface high pressure spreads eastward over the western Atlantic, winds and seas will gradually decrease tonight. A strong cold front will then push southward through the local waters late Monday and into early Tuesday. Behind the front, hazardous marine conditions are expected for most local waters as north or northeast winds increase along with an increasing northeasterly swell off the Palm Beach Coast. BEACHES... A high risk of rip currents along the Atlantic beaches through the remainder of today. The rip current threat will remain elevated through the start of the new workweek and into midweek as a strong easterly wind develops and northeasterly swell builds. && .PRELIMINARY POINT TEMPS/POPS... Miami 70 81 66 76 / 50 50 50 40 West Kendall 68 82 65 77 / 40 50 50 40 Opa-Locka 68 81 65 76 / 50 50 50 40 Homestead 69 80 64 76 / 40 50 50 50 Fort Lauderdale 70 80 66 75 / 50 60 60 40 N Ft Lauderdale 70 81 67 75 / 50 60 60 40 Pembroke Pines 68 81 64 75 / 50 50 60 40 West Palm Beach 68 81 64 74 / 50 60 60 40 Boca Raton 69 81 66 75 / 50 60 60 40 Naples 68 81 62 77 / 20 20 10 10 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...High Rip Current Risk until 7 AM EST Monday for FLZ168-172-173. AM...None. GM...None. && $$ Update...Molleda Visit us at weather.gov/miami Follow us on Facebook and Twitter at: www.facebook.com/nwsmiami www.twitter.com/nwsmiami
Area Forecast Discussion
National Weather Service Melbourne FL
942 PM EST Sun Jan 9 2022 .UPDATE... ...Deteriorating Marine Conditions Arrive Along with Cold Front Tomorrow... Current-Tonight...A moderately-complex forecast in store for the overnight hours with the approach of a cold front across the northern half of the peninsula and increasing moisture spreading across the southern tier. Tonight, central FL gets positioned between the two, with effects from both arriving in the next several hours. So far, only minimal rain chances are present across Martin County this evening, prompting the adjustment of the PoP forecast over the next several hours, however rain chances for the Treasure Coast are expected to increase after midnight with HRRR runs in favor of scattered showers accompanied by a few rumbles of thunder ejecting north out of Palm Beach County then spreading along the warm Gulf Stream waters. At the same time, isolated pop-up showers may develop over interior areas along the Kissimmee River and towards Orlando. Highest coverage expected from Lake Okeechobee to the Treasure Coast overnight at 40-50%, with a slight chance of thunderstorms at the immediate coast, then spreading north towards the southern Space Coast by daybreak. Also prior to sunrise, patchy fog will be possible over Lake and portions of western Orange counties due to arriving moisture ahead of the cold front. Warm overnight lows will only fall to the mid 60s with increasing cloud cover. Tomorrow...(modified previous) Latest HRRR runs have backed off with early morning robust weather, keeping most rain chances out of the forecast until the late morning as the cold front reaches south of I- 4. Updated the forecast to slightly reflect this, just eliminating showers north of I-4 prior to 10am with a general increase in rain chcs beginning mid- late morning and into the afternoon ascd with approach of the front. Predominant showers (sct-nmrs) along with a small chc of thunder can be expected with passage of the frontal zone, bringing higher rain chcs from N-S during that time period. The set up for storms is not as ideal as temps near -12C to -14C @ H5 combine with only marginal at best kinematics aloft to produce a small chc of an embedded storm or two across the area. Despite the advertised front, highs will make it to the U70s to L80s. Winds will veer quickly north after psg of the front largely before dusk with post-frontal drying steadily moving swd in the early evening hours effectively ending rain chcs. && .AVIATION... Moisture will increase this evening and through the overnight from the south, bringing isolated showers to Treasure Coast terminals through daybreak, with the potential for embedded thunderstorms through 12Z. An approaching cold front from the north adds the potential for patchy fog development at interior terminals after 09Z this morning, so included cig/vis reductions through daybreak. The cold front will shift north to south today, bringing scattered to numerous showers with isolated storms initially at KLEE/KDAB and shifting south through the afternoon. NW winds veer N behind the frontal passage, with slowly clearing skies. Mainly VFR overnight, with increasing likelihood for prevailing MVFR and brief IFR conditions through the TAF period. && .MARINE... Tonight...Southeast winds 5-10 knots will veer southwest overnight ahead of an approaching cold front. Increasing moisture will allow for the potential for scattered shower and isolated thunderstorms to spread over the Gulf Stream waters through daybreak. Seas remain 3-5 ft. Tomorrow...As the cold front shifts south through the Atlantic waters, west to northwest winds will become northerly, increasing to 20-25 knots by early afternoon. This has prompted the issuance of a Small Craft Advisory for all waters north of Sebastian Inlet, which will be expanded across all marine zones. Seas will be slower to respond to the wind surge, remaining at 3-5 ft tomorrow but increasing later in the night. Scattered to numerous showers with isolated thunderstorms are expected tomorrow across all Atlantic zones. && .PRELIMINARY POINT TEMPS/POPS... DAB 64 76 54 66 / 20 50 10 10 MCO 65 81 56 69 / 20 50 10 10 MLB 64 79 60 70 / 30 60 30 20 VRB 64 82 62 74 / 40 70 50 30 LEE 65 78 50 68 / 20 40 0 0 SFB 64 78 55 68 / 20 40 10 10 ORL 66 80 55 69 / 20 40 10 10 FPR 63 81 61 71 / 40 70 50 30 && .MLB WATCHES/WARNINGS/ADVISORIES... FL...None. AM...Small Craft Advisory from 4 PM Monday to 1 AM EST Tuesday for Flagler Beach to Volusia-Brevard County Line 0-20 nm- Flagler Beach to Volusia-Brevard County Line 20-60 nm- Volusia-Brevard County Line to Sebastian Inlet 0-20 nm- Volusia-Brevard County Line to Sebastian Inlet 20-60 nm. && $$ SHORT TERM...Smith LONG TERM....Combs AVIATION...Smith
AREA FORECAST DISCUSSION...UPDATED
National Weather Service Morristown TN
927 PM EST Sun Jan 9 2022 .UPDATE... EVENING UPDATE. && .DISCUSSION... Precip has rapidly come to an end this evening as the cold front pushed through the TN valley and into the Appalachians. Have updated PoPs accordingly, only holding on to some mentionable rain chances for the next 2-3 hours in the Smokies mainly as some low level moisture remains trapped in upslope flow through that time. Radar shows some light returns in those areas that extend west from the mountains a tad so I suspect there are legitimate showers ongoing at the moment. That said, dewpoints have dropped into the mid 20s across portions of the northern plateau, so these showers will not last long. Regarding dewpoints, model guidance is handling the dewpoint drops rather nicely so did not make any chances to that for the overnight hours. However, temperatures are not falling quite as fast as expected and with the lingering mid/high clouds expected through the night coupled with elevated winds, I think overnight lows may be a touch warmer than previously forecasted. While I think the HRRR is probably bullish in the warmer direction, the trends in that model over the last several runs point to warmer temperatures tonight. Additionally, locations on the SPC SREF plumes page that track hourly vs forecast temps, show a cold bias in the most recent runs, also supporting bumping temperatures up a notch tonight. In the end, did a blend of the previous forecast, the HRRR, and also some CONSShort with effectively bumped lows up 1-3 degrees depending on the location. The biggest changes were in the north. CD && .AVIATION... 00Z TAF DISCUSSION. Rain should clear all terminals by 00z so just have some minor vsby restrictions and MVFR ceilings at TAF sites through 02-03z before drier air and better flight categories make it into the TN valley. Expect only high clouds by 07z. Winds will remain gusty through the overnight hours as surface pressure gradients increase across the region. CD && .PRELIMINARY POINT TEMPS/POPS... Chattanooga Airport, TN 30 47 26 44 27 / 20 0 0 0 0 Knoxville McGhee Tyson Airport, TN 25 42 21 40 25 / 50 0 0 0 0 Oak Ridge, TN 24 43 20 40 24 / 20 0 0 0 0 Tri Cities Airport, TN 22 37 16 36 21 / 80 0 0 0 0 && .MRX WATCHES/WARNINGS/ADVISORIES... NC...NONE. TN...NONE. VA...NONE. && $$