Area Forecast Discussion
Issued by NWS Albany, NY

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
-- Highlight Changed Discussion --
-- Discussion containing changed information from previous version are highlighted. --
000 FXUS61 KALY 170530 AFDALY Area Forecast Discussion National Weather Service Albany NY 1230 AM EST Fri Nov 17 2017 .SYNOPSIS... Rain showers will transition to snow showers tonight, with some accumulating snowfall over the higher terrain mainly north of the Capital District. Cold and brisk conditions in store for Friday, as high pressure builds eastward from the Great Lakes. A stronger storm system will approach on Saturday, bringing the next chance for widespread precipitation. && .NEAR TERM /UNTIL 6 AM THIS MORNING/...
-- Changed Discussion --
As of 1230 AM EST...Made some minor adjustments to the rest of the overnight, mainly to increase cloud cover and increase pops across northern Herkimer/Hamilton counties where NY mesonet obs indicate numerous snow showers falling. Upslope snow noted on radar along and just west of the spine of the southern Green Mountains, although activity does look to be light. Will maintain likely pops there for a few more hours. Gusty winds will persist across the area overnight. 00Z ALY sounding showed steep low level lapse rates - sfc to 850mb of 8C/km. VAD wind profile depicting winds to 45 knots up to about 850mb. RAP soundings show good mixing to continue through the night. Highest wind gusts down the Mohawk Valley into the Capital District and Berkshires. Rain showers have transitioned to snow showers across the higher terrain as colder air filters in. Hi-res guidance continues to show a decided diminishing trend in precipitation through the night. This is accounted for in current forecast. The winds and mostly cloudy conditions should prevent temperatures from falling as much as they could but the deepening cold advection will help temperatures fall to around 30 to the mid 30s but mid to upper 20s in the southern Adirondacks.
-- End Changed Discussion --
&& .SHORT TERM /6 AM THIS MORNING THROUGH SUNDAY/... Upper energy exits and the cold advection continues with breezy west to northwest winds. Sources of guidance suggest quite a bit of sunshine Friday but with wind off the warm lakes, there may be intervals of clouds and sun until afternoon when the winds diminish more rapidly. Still some sun and wind should help temperatures reach solidly in the 40s but 30s in the southern Adirondacks. The next system approaches through Friday night with warm advection rapidly increasing. Some question as to the timing of the onset of thicker cloud cover and increasing low level winds. Current sources of guidance suggest a period of clear and calm conditions Friday evening, allowing temperatures to fall to the upper teens and lower 20s before thicker clouds and increasing south winds help temperatures to rise into the upper 20s by daybreak Saturday. The timing of the onset of precipitation looks to be after daybreak to mid morning Saturday in western areas, when temperatures rise above freezing. Boundary layer temperatures are expected to be above freezing at that time, so other than a possible brief light mix of rain, snow and/or sleet for an hour or two, precipitation over our region Saturday and Saturday night should be rain. No accumulation is expected. Southwest boundary layer flow becomes quite strong Saturday along with strengthening isentropic lift and upper dynamics, supporting a widespread rain through Saturday night. Highs Saturday in the mid 40s to around 50. Temperatures will fall with the frontal passage mainly just after daybreak Sunday into the mid 30s to lower 40s. Deep cold advection spread across the region Sunday with very strong west to northwest boundary layer flow, much of which is likely to mix to the surface. The cold air over the Great Lakes should aid in the development of some lake effect snow shower activity that should extend east into our region, with the best coverage in the southern Adirondacks but scattered activity that could extend through the region into western New England. Highs Sunday in the 40s to near 50 but 30s in the southern Adirondacks and temperatures falling in the afternoon. && .LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... Sunday night-Monday looks to remain active in the wake of the strong weekend storm system. Lingering Lake Effect/Enhanced snow bands look to potentially impact portions of the western Mohawk Valley and western Adirondacks through Monday, with additional enhancement possible across west facing higher terrain of the southern Greens and northern Berkshires. Some filaments of snowbands could occasionally extend into valley areas. It should remain windy, with some gusts possibly approaching or exceeding 40 mph within portions of the Mohawk Valley/Capital Region and Berkshires. It should remain cold, with Sunday night lows ranging from the teens across the Adirondacks, to the 20s elsewhere. Highs Monday ranging from the upper 20s across the Adirondacks, to the mid 30s/lower 40s in valley areas. For Tuesday-Wednesday, most 12Z/16 global deterministic models and ensembles suggest a fast moving northern stream system passes north of the Great Lakes and across SE Canada. A brief surge of milder air should allow temps to reach into the 40s/lower 50s for much of the region Tuesday afternoon, except cooler across the Adirondacks. Some rain/snow showers will be possible within the warm advective regime, possibly combining with some Lake Enhanced moisture, across the western Adirondacks Tuesday afternoon. Then, slightly greater coverage of rain/snow showers for Tuesday night into Wednesday morning, as a cold front associated with the system moves through. Temps should fall into the 20s and 30s by daybreak Wed, with highs Wed mainly in the 30s to lower 40s. High pressure looks to build into the region Wednesday night and Thursday, assuming southern stream moisture/energy does not track farther north. It should be rather chilly, with lows Wed night in the teens and 20s, with Thursday highs mainly in the 20s and 30s. && .AVIATION /06Z FRIDAY THROUGH TUESDAY/... Expect VFR conditions at most terminals through the period. Exception will be KPSF where westerly upslope flow will induce some MVFR clouds tonight. Expect gusty winds to persist through the period at all terminals. Winds should be stronger at KALB and KPSF. Outlook... Friday Night: No Operational Impact. NO SIG WX. Saturday: High Operational Impact. Likely RA. Saturday Night: High Operational Impact. Breezy Definite RA. Sunday: Moderate Operational Impact. Windy With Gusts To 39.0 Chance of SHRA. Sunday Night: Low Operational Impact. Breezy Isolated SHSN. Monday: Low Operational Impact. Breezy Isolated SHSN. Monday Night: No Operational Impact. NO SIG WX. Tuesday: Low Operational Impact. Breezy NO SIG WX. && .FIRE WEATHER... Rain showers will transition to snow showers tonight, with some accumulating snowfall over the higher terrain mainly north of the Capital District. Cold and brisk conditions in store for Friday, as high pressure builds eastward from the Great Lakes. A stronger storm system will approach on Saturday, bringing the next chance for widespread precipitation. Gusty west to west winds expected tonight and Friday, up to 35 mph in some spots. Winds diminish to light and shift to south Friday night, increasing to around 15 mph Saturday. RH values remaining above 35 percent through Saturday with widespread rain expected Saturday. && .HYDROLOGY... No hydrologic problems are expected on the main stem rivers through the next week. High pressure will briefly build in on Friday before a strong low pressure system approaches from the Great Lakes Region on Saturday. Widespread rain may begin as a mix with snow in the western Mohawk Valley and southern Adirondacks but then change to to all rain that will continue through Saturday night. A cold front will sweep through Sunday morning with additional precipitation. At this time, total QPF from this system looks to range from a half inch to near an inch. For details on specific area rivers and lakes, including observed and forecast river stages and lake elevations, please visit the Advanced Hydrologic Prediction Service /AHPS/ graphs on our website. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. MA...None. VT...None. && $$ SYNOPSIS...NAS NEAR TERM...OKeefe/NAS/JPV SHORT TERM...NAS LONG TERM...KL AVIATION...KL/OKeefe FIRE WEATHER...NAS HYDROLOGY...NAS is the U.S. government's official web portal to all federal, state and local government web resources and services.