Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 02/19/22


AREA FORECAST DISCUSSION
National Weather Service Albany NY
1034 PM EST Fri Feb 18 2022 .SYNOPSIS... Higher pressure will shift across the region tonight. A fast moving clipper system and cold front will bring snow showers, squalls and gusty winds on Saturday. Drier weather returns on Sunday and Monday before the next system arrives on Tuesday. && .NEAR TERM /UNTIL 6 AM SATURDAY MORNING/... Higher pressure will continue to shift across the area tonight and weakens as it does. Lake effect flurries have ended as a short wave moves off to the east. Winds have diminished and will become southerly overnight as the high shifts off to our east and a clipper system approaches from the Great Lakes Region. Some light snow associated with this clipper will start prior to daybreak for areas north and west of Albany. It will be much colder than last night with lows in the single digits and teens. The lows will occur around midnight or so with temperatures stabilizing then rising overnight in warm air advection. && .SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/... Snow squalls and gusty winds likely on Saturday... Winter Weather Advisory in effect for northern Herkimer and Hamilton counties from 4 am Saturday to 7 pm Saturday... Wind Advisory in effect for the Mohawk and Schoharie valleys, Capital District, eastern Catskills, Taconics and mid-Hudson Valley in New York, western Massachusetts and northwestern Connecticut from 10 am Saturday to 10 pm Saturday... Impressive upper-level vort and surface clipper system will push across the region on Saturday. A warm front will first lift across the region Saturday morning with a period of light snow, especially for areas north of I-90 due to upslope enhancement. Thereafter, a strong cold front will then progress from west to east. Hi-res guidance is favoring an environment with strong low-level lapse rates, convergence along the front, strong pressure rises behind the front as well as the development of weak MUCAPE values up to around 100 J/kg. All of these ingredients favor the organization of a linear line of snow squalls along the front. Due to its linear nature, a quick but rapid deterioration in conditions is expected with a quick coating of snow possible as well as gusty winds between 40 and 50 mph and reduced visibility. These snow squalls shouldn`t last more than 30 minutes in any given location. Timing of these snow squalls slightly varies amongst the hi-res guidance with the HRRR trending faster by a couple of hours from the latest 3km NAM. Therefore, we went with a `middle approach` in terms of pops to highlight when the most likely timing of snow squalls could be. Latest estimated times include the Adirondacks and Mohawk Valley between 10 am and noon, Hudson Valley between noon and 2 pm and western New England between 2-3 pm. These times may need to be adjusted forward or backward in later updates. In the wake of this front, a rapid drop in temperatures and a wind shift to the west is expected for the remainder of the afternoon and into the evening. Wind gusts 40 to 50 mph may persist in some areas. Therefore, a wind advisory has been issued for areas along and south of I-90 with the Mohawk and Schoharie valleys, Capital District and Berkshires likely to have the strongest winds. Temperatures should reach the 20s to 30s ahead of the cold front before dropping to the teens and 20s in the wake of the front during the afternoon. Areas that rise above freezing prior to the passage of the front could deal with flash freeze issues as temperatures quickly fall below freezing and wet roads from the snow squalls turns icy. In the wake of the front, lake-effect snow showers will set up across northern Herkimer and Hamilton counties during the afternoon. A gradual wind shift to the northwest will shift this band southward impacting portions of the Mohawk Valley during the late afternoon and evening hours before drifting south of our area and dissipating. It is possible some broken fragments of this band reach portions of the Capital District and into western New England. With moderate snowfall amounts possible from the light snow ahead of the front, snow squalls with the front and lake-effect snow behind the front, a Winter Weather Advisory has been issued for northern Herkimer and Hamilton counties. Snowfall amounts of 3 to 6 inches is expected with localized amounts up to 8 inches. High pressure returns for Saturday night with the return of drier weather with winds gradually subsiding. It will be quite cold Saturday night with lows below zero across the Adirondacks and southern Greens to the single digits to low teens elsewhere. Dry weather will continue Sunday and Sunday night with high pressure nearby. A southerly wind flow will resume later Sunday into Sunday night. This will result in lows Sunday night not as cold as Saturday night. Highs Sunday in the mid-20s to mid-30s with lows Sunday night mainly in the 20s. && .LONG TERM /MONDAY THROUGH FRIDAY/... Active weather pattern continues through the long term period, along with changeable temperatures. Mild and fairly tranquil conditions should start the long term for Monday-Monday night, although will have to watch for a possible cold front settling southward from eastern Canada. Little in the way of forcing with this boundary, so not expecting much other than some clouds across northern areas. Highs Monday ranging from 35-40 across higher terrain northern areas, to 45-50 in valley areas south and east. Lows Monday night ranging from the mid 20s to lower 30s. Southern stream system then tracks toward the Great Lakes region for Tuesday-Tuesday night. Surge of mid level warm advection should allow precipitation to develop during Tuesday, and continue through Tuesday night, before becoming more showery Wednesday as a cold/occluded front tracks across the region. We will have to watch a cold air mass lingering just north of the region with strong high pressure slowly departing southeast Canada, as there is some potential that shallow, low level cold air may drain south into at least portions of the southern Adirondacks/upper Hudson Valley and southern VT, leading to mixed precipitation, especially during Tuesday. For now, have indicated mainly rain/snow mix, but sleet/freezing rain is certainty possible as well in some of these areas. Have trended cooler than NBM max temps for Tuesday for northern areas to account for the possibility of colder air lingering farther south than current models suggest, with highs in the mid/upper 30s for northern areas, and mid 40s to lower 50s elsewhere. Lows Tuesday night mainly in the 30s and 40s, although may be colder across the SW Adirondacks. Highs Wednesday could be quite mild for areas south and east of Albany, depending on timing of cold front from the west, and also extent of lingering cold air to the north, with 50s or higher possible, and mainly 40s to the north and west. A possible break in the active weather may occur for Thursday, although can not rule out some spotty light precipitation for southern areas, depending on some additional southern stream energy tracks eastward. Temps should be colder, with highs Thursday mainly in the 20s and 30s. There is some consistency in long term guidance for another southern stream system to approach the region for late Thursday night into Friday. There are also some signals in this guidance of a warm nose aloft, with cold air beneath, potentially anchored by a strong mid/upper level confluent flow over southeast Canada. This could bring a wintry mix to the region after some initial snow, perhaps eventually changing to rain for some southern areas. Trends will need to be watched, as the southern stream origins of this system may allow for considerable moisture transport into the region. Highs Friday mainly in the 20s and 30s, after early morning lows in the teens and 20s. && .AVIATION /04Z SATURDAY THROUGH WEDNESDAY/... A ridge of high pressure will drift across the TAF sites overnight. A clipper type storm system will track north of the TAF sites during Saturday, with a strong cold front crossing the TAF sites during the early afternoon hours. Mainly VFR conditions expected through daybreak, although there is a slight chance for some lake effect clouds producing a brief period of MVFR/VFR Cigs at KALB, KGFL and KPSF through around 06Z/Sat. An area/band of light snow associated with the clipper should move across the TAF sites between roughly 13Z-16Z/Sat, producing a period of IFR Vsbys and MVFR/IFR Cigs. The best chance for this occurring will be at KGFL, KALB and KPSF. Then, a line of snow squalls will be possible along the cold front between roughly 16Z-20Z/Sat. As this passes across, a very brief period (perhaps only 15 minutes or less in duration) of LIFR/VLIFR conditions and strong wind gusts of 40+ KT will be possible at all the TAF sites. In the wake of the cold frontal passage and snow squalls, some lingering snow showers or flurries may occur at KALB and KPSF, with scattered brief periods of MVFR/IFR Vsbys possible. Otherwise, mainly VFR conditions should develop, with Cigs generally 3500-5000 FT AGL. West/northwest winds 8-12 KT this evening, with a few lingering gusts up to 20 KT possible, then quickly decreasing to less than 5 KT after midnight through around daybreak. Then, winds will become south to southwest and increase to 8-15 KT, with gusts of 20-25 KT developing by mid morning Saturday through mid afternoon. Winds will then shift into the west to northwest, and increase to 10-20 KT, with gusts of 30-40 KT possible in the wake of the front. There could be a brief period of low level wind shear between 09Z-13Z/Sat at any TAF site with surface winds remaining below 8 KT, as winds around 2000 FT AGL increase from the south to southwest to 30-40 KT. This potential looks greatest at KGFL at this time, and thus has been included in current (00Z/Sat) TAF issuance. Outlook... Saturday Night: Moderate Operational Impact. Windy With Gusts To 33 kts. NO SIG WX. Sunday: No Operational Impact. NO SIG WX. Sunday Night: No Operational Impact. NO SIG WX. Washingtons Birthday: No Operational Impact. NO SIG WX. Monday Night: No Operational Impact. NO SIG WX. Tuesday: High Operational Impact. Definite RA. Tuesday Night: High Operational Impact. Definite RA. Wednesday:Low Operational Impact. Breezy. Slight Chance of RA. && .HYDROLOGY... Flooding is not expected to pose a threat, however localized ice jams can`t be rule out. Generally light precipitation amounts are expected on Saturday with any precipitation in the form of snow. Dry weather is expected on Sunday and Monday before the next system arrives on Tuesday with mostly rainfall. 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...Wind Advisory from 10 AM to 10 PM EST Saturday for CTZ001-013. NY...Wind Advisory from 10 AM to 10 PM EST Saturday for NYZ038>040- 047>054-058>061-063>066. Winter Weather Advisory from 4 AM to 7 PM EST Saturday for NYZ032-033. MA...Wind Advisory from 10 AM to 10 PM EST Saturday for MAZ001-025. VT...None. && $$ SYNOPSIS...IAA/Rathbun NEAR TERM...IAA/Rathbun SHORT TERM...Rathbun LONG TERM...KL AVIATION...KL HYDROLOGY...Rathbun
Area Forecast Discussion
National Weather Service Binghamton NY
1051 PM EST Fri Feb 18 2022 .SYNOPSIS... A strong cold front will move sweep through the area Saturday morning. A narrow snow squall is expected to sweep across the area, bringing a brief burst of heavy snow, strong winds, and near zero visibility. Additional snow showers and squalls will continue through the afternoon over parts of Central New York, with gusty winds across a wider area. Lake effect snow bands will also develop and persist into the evening. && .NEAR TERM /THROUGH SATURDAY NIGHT/... 1045 PM Update... Temperatures have dropped into the 10s and single digits over the area as clouds diminish, and winds slacken under a ridge of high pressure. Weak warm advection may take the edge off the cold temperatures across the Finger Lakes in the pre-dawn hours, as southerly flow develops ahead of an approaching Arctic cold front. That front is currently slicing through Lake Michigan and into northern Illinois, with an intense snow squall extending from southern Wisconsin into eastern Iowa. Visibilities have dropped to near zero in places with wind gusts in excess of 50 mph. Higher-res model guidance (CAMs) are in very good agreement on the timing of the snow squall, which looks to maintain itself through the night as it plows through the Midwest U.S. and southern Ontario, reaching western New York around dawn. For us, the mass fields are still favorable for snow squalls, with a strong vort max moving through the area and keeping pace with the cold front. Although it`s quite cold outside now, the airmass behind the front is much deeper, and will continue to provide strong low level convergence as it moves through NY/PA tomorrow. Snow squall parameter is well above 1 ahead of the front, aided by strong low level convergence, steep low level lapse rates, and strong instability (for winter) of 100-150 J/Kg per the NAM12. With the very good agreement in timing on the CAMs (with the NAM and NAMnest slightly slower), went ahead and timed a narrow band of categorical PoPs across the area, with "Brief Heavy Snow" and blowing snow attributes. Best timing brings the squall into the far western CWA around 13Z (8 AM), SYR/ITH/ELM around 14Z (9 AM), Bing/Norwich/Utica around 15 or 16 (10-11 AM), Oneonta down through Scranton/W-B around 16-17Z (11 AM-Noon), and east of Monticello between 18-19Z (1-2 PM). The main squall itself may only last a half hour, which will limit accumulations, but the main impact will be for anyone stuck on the roads at the wrong time. Cyclonic flow and strong CAA will keep the risk of additional snow showers and perhaps the odd smaller squall around Central NY through the afternoon. Confidence in how the afternoon snow showers and lake effect bands evolve is much lower, and will be influenced by a secondary shortwave trough and reinforcing cold front dropping across Lake Ontario late in the afternoon, shifting winds from mostly westerly to NW. The best chance for persistent lake effect will be up across the Thruway corridor, with accumulations of 1 to 2 inches possible. Additional lake bands, mainly influenced from Lake Huron, may develop as far south as the Southern Tier, with NE PA staying dry through most of the afternoon. A few HRRR runs suggest the main E-W oriented Lake Ontario band may breakaway as a squall as the secondary front moves through late in the afternoon or early evening (plausible, but not guarantied). Either way, NW-SE oriented multi-bands will set up as the wind shifts, and persist into the evening, mainly focused on parts of Onondaga, Cortland, and southern Seneca Counties. Additional light accumulations will be possible. 335 PM Update... A ridge of high pressure building in this afternoon is slowly drying out the lower atmosphere with the lake effect snow showers coming to an end late this afternoon. With the high pressure in place and winds calming down, and mostly clear skies, low temperatures fall into the low teens and single digits. Tomorrow once again is active with a strong shortwave moving through with an associated arctic front moving through. Low level lapse rates are near dry adiabatic to 700 mb with the frontal passage with some weak CAPE and good lift through the DGZ. The boundary layer mean winds are 40-50 knots with the passage of the front so there will likely be some strong snow squalls tomorrow morning into the early afternoon across CNY into NEPA. Behind the front, cold air advection and a tight pressure gradient will make for some strong synoptic winds tomorrow afternoon into the evening hours. Downward momentum transfers in bufkit is showing wind gusts up over 45 mph at times, especially across higher terrain. Lake effect snow downwind of Ontario looks to graze Northern Oneida Co with 4-6 inches of snow so a winter weather advisory was posted. Further South and west across the eastern Finger Lakes, lake effect snow will also move through late tomorrow afternoon through the first half of the night with 1-3 inches of snow possible. Ridging builds in through the overnight hours Saturday with snow and winds lessening and once again another cold night. && .SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/... 300 PM Update... Dry and sunny weather returns Sunday with zonal flow aloft and a surface high centered over the southeastern US. A shortwave moving through southern Ontario will lead to a tightening pressure gradient and increasing southwesterly flow, allowing a warmer airmass to advect in once again. Temperatures start in the single digits, but quickly rise into the 30s, and possibly closer to the 40F mark in the valleys. Expect otherwise breezy conditions. Dry and increasingly warmer weather continues Monday as a trough digs into the western US and heights rise across the east in response. Temperatures start off in the 20s Monday morning and peak in the 40s and 50s during the afternoon. Still thinking that most of the area will stay dry through Monday night, but as the low level jet starts to nose in ahead of the deepening central US trough, this may lend some dynamical support for some light precipitation. What form this takes remains uncertain. There will be a fairly robust warm nose for the lowest several thousand feet, but surface temperatures may still be able to fall to near freezing. So, we should be seeing mainly rain, but some pockets of freezing rain are still possible. Some snow would still not be out of the question if precipitation can develop early in the night, before that warming aloft really takes off. && .LONG TERM /TUESDAY THROUGH FRIDAY/... 300 PM Update... More active weather returns for the remainder of the forecast period with a couple larger systems for Tuesday and for later in the work week. Precipitation changing over to rain will become likely Tuesday as a deepening surface low moves into the Great Lakes and a strong southwesterly flow out ahead of it continues to pump warm, moist air into the Northeast. PWATs increase to up to 1 to 1.5 inches, as much as three standard deviations higher than climatology, with a prolonged period of rain for much of Tuesday and Tuesday evening. It`s early, but ensemble guidance is indicating some higher totals around an inch, especially in the upslope areas of the Catskills, Poconos, and Tug Hill. There are indications for our area to get into the dry slot late Tuesday night into early Wednesday, with precipitation largely wrapping up. Any lingering precipitation Tuesday night into Wednesday should continue to fall as rain, with 850mb temperatures still well above freezing at least for the first half of the day. However, The upper trough finally moves through later in the day Wednesday with cooling temperatures into the evening and overnight hours. This could be enough to touch off some lake effect snow showers Wednesday evening into early Thursday, though most of the area should remain dry with a period of ridging over the region while yet another trough digs into the central US. This will lead to a shift back over to southerly flow and resultant warm air advection with chances for precipitation filling back in from south to north. && .AVIATION /03Z SATURDAY THROUGH WEDNESDAY/... Some lake effect snow showers will impact RME through about 03z this evening, bringing MVFR, and brief IFR VSBYs. Then VFR expected here overnight. Tonight will be mostly VFR across the region. A low pressure system passes by to the north late tonight, bringing a warm front with some light snow breaking out from SYR, RME, ITH and ELM around 12z Saturday morning. Then, a strong arctic front moves through late Saturday morning or early afternoon. With steep low level lapse rates and some instability in the morning, snow squalls are likely. Timing is still a bit uncertain for the actual frontal passage and main snow squall, but a 2-3 hour tempo was added at all terminals during the most probable timing. This squall is expected to move quickly west to east across the area between about 13z and 17z Saturday...perhaps until 18z at AVP. This squall is forecast to be quite intense, with gusty winds (25-35 kts), brief heavy snow and blowing snow. VSBYs could briefly go under 1/4SM or 1/8SM in some locations. Near whiteout conditions cannot be ruled out. Saturday afternoon will feature improving conditions, but still a few snow showers or isolated squalls around. A lake effect snow band moves back into RME and SYR around or just after 20z Saturday and lingering into the evening hours with low end MVFR fuel alternate or even IFR conditions expected. The rest of the terminals will have just some isolated snow showers or flurries around, and be mainly VFR. However, some additional snow showers could move toward ITH and BGM toward the end of the taf period (00z Sunday) perhaps bringing occasional MVFR restrictions here. Outlook... Saturday night...Snow showers continue into the afternoon and overnight with restrictions at times, mainly CNY terminals Sunday into Monday...Mostly VFR. Tuesday into Wednesday...Rain or mixed precipitation with associated restrictions. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...Wind Advisory from 10 AM to 10 PM EST Saturday for PAZ038>040- 043-044-047-048-072. NY...Wind Advisory from 10 AM to 10 PM EST Saturday for NYZ015>018- 022>025-036-037-044>046-055>057-062. Winter Weather Advisory from 4 AM to 7 PM EST Saturday for NYZ009. && $$ SYNOPSIS...MPH NEAR TERM...AJG/MPH SHORT TERM...HLC LONG TERM...HLC AVIATION...AJG/MJM