099 FXUS61 KALY 061732 AFDALY AREA FORECAST DISCUSSION National Weather Service Albany NY 132 PM EDT Wed Oct 6 2021 .SYNOPSIS... Partly sunny to mostly cloudy skies today with high pressure building in from the northeast. Clouds and areas of fog may redevelop tonight and linger in some valley areas until midday Thursday, before skies become mostly sunny with milder afternoon temperatures. Generally fair weather is expected Friday through Saturday as high pressure remains in control. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... As of 115 pm...Clouds continue to gradually erode particular to the northwest of the Capital District and in the Connectcut River Vally in VT. The 12Z ALY sounding indicates a strong inversion in place from around 900 to 850 mb with very dry air above that. Winds are light and variable across the area with the surface high in place. Made adjustments on observational data and trends and blended withe latest guidance. Still expecting highs this afternoon in the 60s with any 50s limited to above 2500 feet. && .SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/... Tonight, mixed signals on cloud cover and fog potential, with most guidance suggesting at least some breaks in the clouds this evening, before fog develops in valley areas, while a higher-based stratus cloud deck may reform and/or linger from the daytime hours across the eastern Catskills, mid Hudson Valley and Berkshires. Have generally sided with partly cloudy skies early, then mostly cloudy after midnight, and have included mention of fog in most valley areas. If the higher-based stratus deck remains more limited in areal extent, then the potential for dense fog formation will increase. Low temperatures mainly in the 50s, although some 40s will be possible across portions of the southern Adirondacks, southern VT and Berkshires, especially if the higher-based stratus clouds remain limited. For Thursday, fog/low clouds may linger through the morning in valley areas, and perhaps until noon within portions of the Lake George area. However, low level flow should become west to northwest and slightly stronger compared to today, so better chances for afternoon clearing across the region. Assuming there is more clearing, temps should reach the upper 60s to lower 70s Thursday afternoon. Fog and low clouds may redevelop Thursday night, with lows ranging from the mid/upper 40s across northern areas, to lower/mid 50s elsewhere. Morning fog/low clouds should give way to more afternoon sunshine Friday, with temps warming into the lower/mid 70s in valleys, and 65-70 across higher terrain. Weak backdoor/sidedoor cold front should move west/southwest across the region Friday night. Winds may increase from the northeast to southeast, which may limit fog potential compared to previous nights. However, some low clouds may develop in the wake of the front, and can not rule out a bit of drizzle for some higher elevations. Lows mainly in the upper 40s to lower/mid 50s. && .LONG TERM /SATURDAY THROUGH TUESDAY/... The period starts out on Saturday with an upper level ridge axis positioned over New England, with a surface anticyclone centered over Maine/New Brunswick. Surface ridging extends south/west through New England and into eastern New York. An easterly low level flow will result in cooler temperatures compared to previous days (but still near normal). Mostly cloudy skies anticipated with the moist easterly flow off the Atlantic. Expecting dry conditions through the day, although an upper level short wave will be approaching from the Great Lakes. The short wave trough will move eastward across our region Saturday night through Sunday. Generally weak forcing should only lead to widely scattered showers during this time. This system looks to be fairly progressive, so showers expected to end by Sunday evening. The surface anticyclone is forecast to drift southward to the Gulf of Maine, so low level easterly flow should continue with mostly cloudy skies persisting. A coastal wave near the Mid Atlantic region is expected to track well south/east of our area for any rainfall at this time. Drying conditions with warmer temperatures expected Monday into Tuesday, as anomalous upper level ridging develops again (500 mb heights of +1 to +2 STDEV). Low level winds turn more southerly, which could result in clouds finally scouring out although it may not occur until the afternoon both days with low stratus clouds moving back in during the nighttime hours. Temperatures should be solidly above normal, with 850 mb temp anomalies of +1 to +2 STDEV from the NAEFS. Assuming some sunshine during the afternoons, highs in the lower to mid 70s will be attainable for valley locations. && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... Abundant low-level moisture trapped beneath a strong inversion is still allowing for some MVFR ceilings. Based on satellite trends and model soundings, will expect ceilings to trend towards VFR for the late afternoon and early evening hours, as some drier air works into the area. All sites should be VFR by 22z with just few-sct cumulus. Winds will be very light and variable this afternoon and evening at 5 kts or less. With some clearing having occurred, radiational cooling will allow temps to fall quickly this evening. With dewpoints still elevated, radiational fog will form for all sites overnight. IFR fog may develop as early as 01z-03z for KGFL/KPSF, but will hold off until after 06z for KALB/KPOU. Will need to watch trends closely this evening to see if this speeds up at all. Calm winds are expected overnight for all sites. Fog/mist should dissipate by 13z-14z for all sites, allowing VFR conditions to return. Sct-bkn cigs around 3500 ft are expected for during the day Thursday with continued very light winds. Outlook... Thursday Night: No Operational Impact. Patchy FG. Friday: No Operational Impact. NO SIG WX. Friday Night: No Operational Impact. NO SIG WX. Saturday: Low Operational Impact. NO SIG WX. Saturday Night: Low Operational Impact. Slight Chance of SHRA. Sunday: Moderate Operational Impact. Chance of SHRA. && .FIRE WEATHER... Mainly cloudy skies this morning will give way to some breaks in the clouds by late afternoon, especially across northern areas as high pressure builds in from the northeast. Clouds and areas of fog may redevelop tonight and linger in some valley areas until midday Thursday, before skies become mostly sunny with milder afternoon temperatures. Generally fair weather is expected Friday through Saturday as high pressure remains in control. RH values will fall to 60-80 percent this afternoon, then recover to around 100 percent tonight with fog and dew formation likely. RH should fall to 60-70 percent Thursday afternoon. Light/variable winds will trend into the north to northeast at less than 10 mph this afternoon, then become nearly calm tonight. && .HYDROLOGY... Most rivers are receding after the moderate to heavy rainfall over the past few days. However, the lower Housatonic may continue to slowly rise through today. No additional flooding is forecast. Generally dry weather is expected from today through at least Saturday, which will allow river levels to fall. 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...IAA/SND/KL NEAR TERM...IAA SHORT TERM...KL LONG TERM...JPV AVIATION...Frugis FIRE WEATHER...SND/KL HYDROLOGY...SND/KL