542 FXUS61 KALY 041505 AFDALY AREA FORECAST DISCUSSION National Weather Service Albany NY 1105 AM EDT Thu Jun 4 2020 .SYNOPSIS... High pressure will briefly build in today with fair weather, as a frontal boundary remains south of the region. A warm front will lift north of the region tonight with some showers and isolated thunderstorms mainly south and east of the Capital Region. A warm and humid air mass will be over the region on Friday with isolated to scattered afternoon showers and thunderstorms possible. A cold front will bring more chances of showers and thunderstorms Friday night into Saturday. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... As of 1045 AM EDT...Forecast is on track and in good shape so only some minor adjustments were needed. The mid and upper level flow will continue to be zonal across the northern CONUS into the Northeast. The weakening boundary across the region will gradually settle southward today as weak high pressure at the surface builds in from the Great Lakes Region and is expected to become stationary in the vicinity of I-80. Fair, dry and warmer today. H850 temps will be above normal in the mid to late pm in the +12C to +16C range with boundary layer west to southwest winds. Max temps will be above normal by close to 10 degrees. Highs will range from the lower to mid 80s in the valley areas, and across the hills. Expect upper 60s to upper 70s over the mtns. Some mid and high clouds will increase from the south and west late in the afternoon, and a few showers may reach the southeast Catskills. && .SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/... Tonight...The old cold front begins to lift northward as a warm front. The winds back to south, and this boundary with weak warm advection will focus some showers and isolated thunderstorms mainly south of the I-90 corridor. The latest 00Z HREFS have mean MUCAPE values generally 500 J/kg or less across the eastern Catskills, mid Hudson Valley, southern Taconics, Berkshires, and NW CT. We did place some isolated thunderstorms in the forecast in the southeast zones. Showalter stability indices lower to 0C to -2C on the 00Z NAM with the elevated instability present. Lows will be on the mild side with increasing humidity levels. Expect lows in the lower to mid 60s from the Capital District south and east, and mid 50s to around 60F north and west. Friday...Eastern NY and western NY gets into a warm sector. The air mass becomes warm and humid with sfc dewpts rising into the lower to mid 60s in the lower elevations, and mid 50s to around 60F over the higher terrain. Some low stratus is possible in the morning from the Capital Region south and east, as well as some isolated to scattered showers from Albany south and east with the warm front moving through. The mid and upper level flow becomes southwesterly. H850 temps rise to +1 to +2 STDEVs above normal. PWATs also increase to +1 to +2 STDEVs above normal in the humid air mass based on the 00Z GEFS. The actual PWATS will be about 1-1.75". A clear lifting mechanism is not present in the afternoon with the cold front well upstream over the eastern Great Lakes Region and southeast Canada. 0-6 km bulk shear values are in the 20-30 kt range on the GFS/NAM. SBCAPES are in the 500-1500 J/kg range. Loosely organized thunderstorms may pop-up due to differential heating. The mid level lapse rates look weak at 6C/km or less. Currently, we are not outlooked for any severe thunderstorms, but we can not rule out an isolated strong one or two. We have a chance of showers or thunderstorms over the forecast area by the mid to late pm. Some locally heavy rainfall may be possible too. Max temps rise into the mid and upper 80s over the valley locations and 70s to lower 80s over the higher terrain. Friday night...The latest NAM/GFS/ECMWF/CMC has the cold front moving towards and across portions of the region during this time frame. The mid and upper level trough over southeast Canada amplifies with the best height falls over the eastern Great Lakes Region, and upstate NY overnight. Scattered showers and thunderstorms are possible. The instability does diminish after midnight. Expect a muggy night with lows in the upper 50s to lower 60s west of the Hudson River Valley, and mainly lower to upper 60s from the Hudson River Valley eastward. Sat-Sat night....The cold front should clear the region in the late morning into the early afternoon. Scattered showers and isolated thunderstorms are possible especially from the Capital Region south and east. The placement of front and any sfc heating will be critical for any strong thunderstorms that may develop. Cold advection will occur in the wake of the front. Max temps may only be in the mid 60s to lower 70s over the southern Dacks. Mid 70s to lower 80s will be common in most other locations, with some upper 60s over the eastern Catskills and southern Greens. We tried to trend to drier conditions for the afternoon period with and earlier frontal passage. The upper level trough may focus some scattered showers north and west of Albany during the pm. Clearing skies and comfortable humidity levels are expected Sat night with lows in the mid 40s to mid 50s. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... The long term portion of the forecast begins with a large surface high pressure building in from Canada. This looks to bring us mostly sunny skies during the day and clear at night for Sunday-Tuesday. Temperatures will initially be closer to seasonal level Sunday- Monday, then warm above normal by Wednesday, as a pocket of low/mid level warming bubbles northward, well to the east of Christobal. Daytime highs mid 60s to lower 70s Sunday, warming to the mid/70s to lower/mid 80s by Tuesday. Overnight lows may be a bit below normal Mon/Tue mornings, with mainly 40s, and some possibility of mid/upper 30s across portions of the southwest Adirondacks. Temps may reach well into 80s in valley areas by Wednesday, with higher terrain areas generally 75-80. Overnight lows will be warmer, mainly in the 50s to lower 60s by Wed morning. The remnants of Christobal should remain to our west, at least through Wednesday. However, moisture from this system could bring some showers to the region by late Wednesday, although there remains uncertainty as to how much moisture ultimately reaches our area, as strong mid/upper level ridging potentially remains nearby. && .AVIATION /15Z THURSDAY THROUGH MONDAY/... A weak cold front will settle south of the region this morning, before drifting back north as a warm front tonight. Any patchy fog/low clouds (mainly at KGFL and KPOU) should lift by 13Z/Thu. Once it lifts, expect VFR conditions at all TAF sites through this afternoon, with occasional passing mid/high level clouds. Mid level clouds should increase after 00Z/Fri, and will have to watch for the possibility of showers approaching from the southwest. For now, have indicated PROB30 groups between roughly 02Z and 06Z/Thu at KPOU, KPSF and KALB, when periods of MVFR Vsbys/Cigs could occur. After the shower threat tapers off, MVFR stratus clouds may develop. Light/variable winds should become west to southwest at 5-10 KT by late morning through this afternoon. There could be a few gusts up to 15-20 KT this afternoon. Winds should become light/variable once again around or shortly after sunset. Outlook... Friday Night: Moderate Operational Impact. Chance of SHRA...TSRA. Saturday: Moderate Operational Impact. Chance of SHRA...TSRA. Saturday Night to Monday: No Operational Impact. NO SIG WX. && .FIRE WEATHER... High pressure will briefly build in today with fair weather, as a frontal boundary remains south of the region. A warm front will lift north of the region tonight with some showers and isolated thunderstorms mainly south and east of the Capital Region. A warm and humid air mass with be over the region on Friday with isolated to scattered afternoon showers and thunderstorms possible. The RH values will lower to 35 to 45 percent this afternoon, and then have an excellent recovery to 85 to 100 percent Friday morning. The RH values will lower to 40 to 55 percent Friday afternoon with the threat of scattered showers and thunderstorms. The winds will be west to southwest at 10 to 15 mph with a few a few gusts of 20 to 25 mph this afternoon. The winds will be south to southeast at 5 to 10 mph tonight, and veer south to southwest at 10 to 15 mph on Friday. && .HYDROLOGY... Widespread hydrologic issues are not expected on the main stem rivers the next several days. Weak high pressure will bring a dry day to the region. The high will shift across the region rather quickly tonight with widespread chances for showers and thunderstorms expected Friday afternoon into Saturday before drier weather returns for the 2nd half of the weekend into early next week. Some locally heavy downpours may occur with any thunderstorms Friday afternoon into Saturday morning in the more humid air mass, which may produce some ponding of water on roadways and low lying areas. 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...Wasula NEAR TERM...IAA/Wasula SHORT TERM...Wasula LONG TERM...KL AVIATION...KL FIRE WEATHER...Wasula HYDROLOGY...IAA/Wasula