Area Forecast Discussion
Issued by NWS Albany, NY
Issued by NWS Albany, NY
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089 FXUS61 KALY 081748 AFDALY AREA FORECAST DISCUSSION National Weather Service Albany NY 148 PM EDT Wed May 8 2024 .SYNOPSIS... A warm front will bring some showers and isolated to scattered thunderstorms this morning. A prefrontal disturbance and a cold front will bring additional showers and thunderstorms in the afternoon and early evening with a few on the stronger side. Seasonable temperatures return on Thursday, as clouds increase and rain moves back in from the south in the afternoon ahead of a warm front and a low pressure system in the Ohio Valley with unsettled weather and cooler temps continuing into Friday. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... .Update...As of 1:00 PM EDT...Warm front continues to slowly lift north across our region. Portions of southern VT remain in the 50s, although temperatures across the rest of the region have reached at least the 60s to 70s, with some near-80 degree readings in the Mid Hudson Valley. Clouds lingered a little longer than expected this morning, but now starting to see more breaks of sun across the region, and this has resulted in a couple of thunderstorms developing across Herkimer County. Pre-frontal trough and associated dew point boundary are currently approaching our western CWA border, and may help to ignite a couple of showers/thunderstorms over the next few hours. SPC mesoanalysis shows up to around 1000 J/kg of SBCAPE south and west of Albany, with 50-60 kt of deep-layer shear. Convection has struggled to initiate so far this morning, but if any storms do develop over the next few hours then they could be on the stronger side with some gusty winds and or small hail. Best chance remains for areas south of I-90 in NY and western CT and MA. The thunderstorms across Herkimer County may briefly have some small hail, but should weaken as they tracks eastwards into a more stable airmass. Will also mention that winds could become gusty this afternoon behind the pre-frontal trough, with some gusts of 30-40 mph already seen across central and western NY. Highs today will be mainly in the 60s to 70s, with some 80s in the Mid Hudson Valley. Please see previous discussion below for more details... .Previous...As the pre-frontal trough tracks through, low-level convergence along the wind shift boundary will provide enough forcing for ascent to spark a few showers and thunderstorms. With the best forcing to our north with an approaching shortwave, showers and thunderstorms will be isolated to scattered in nature. However, SPC mesoanalysis and CAMs suggest that there will be an overlap of SBCAPE of over 1000 J/kg as mid-level lapse rates steepen to over 7C/km and deep-layer shear of 50-60 kt. This will allow for a couple storms to be strong to severe, with the greatest threats being damaging wind gusts and hail. Greatest threat area will be for areas along and south of the warm front, which includes the eastern Catskills, Mid Hudson Valley, and western CT and MA. Timing of any strong to severe storms looks to be from around noon through 4 pm. Behind the pre-frontal trough, drier air is advected into the region, which when combined with the loss of daytime heating should allow for instability to decrease and limit the overall severe threat. Another round of showers and a few thunderstorms is expected late this afternoon and evening across the Adirondacks and Mohawk Valley, but waning instability here should limit the severe threat. Temps should rise above normal in the warm sector and due to some downsloping off the Helderbergs/southern Dacks/eastern Catskills we could see max temps spike with the southwest/west flow with the prefrontal trough. Max temps were raised in the the mid 70s to around 80F in the valleys with 60s to lower 70s over the higher terrain. The lower 80s will be near KPOU. && .SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/... Tonight...The main cold front approaches from the west late in the afternoon into the early evening. Additional scattered showers or isolated to scattered thunderstorms will form with less instability. These storms are not expected to be severe. The best chance of showers activity will be from the Capital Region north and west. Cold advection will occur in the wake of the front with lows in the 40s, except lower 50s from the Capital District south and east. We did not add any patchy fog yet due to partly to mostly cloudy conditions and a west to northwest breeze overnight. Thursday...the mid level flow becomes zonal over the Northeast in the wake of the first system. A brief break in the pcpn action is possible in the morning, but then the old cold front begins to lift northward again ahead of the next wave ejecting from the Midwest into the Ohio Valley. The isentropic lift increases again for a period of showers/rain initially south of I-90 in the late morning/early pm but then expanding northward. This is all occurring ahead of a positively tilted mid and upper level trough over southeast Canada, the Great Lakes Region and Midwest. Temps will not be able to recover from normal seasonal readings due to thickening and lowering clouds. Highs will be in the mid and upper 60s in the lower elevations with 50s to lower 60s over the hills and mtns. Thursday Night through Friday night...A sfc cyclone slides east from the Mid Atlantic Region/NJ Coast Thu night with scattered showers persisting due to the upper level low nearby. In the dank air mass lows will be in the 40s with some upper 30s over the southern Greens/southern Dacks. Yet another short-wave impulse rotating around the broader mid and upper level trough is expected to bring another period of rainfall on Friday. The differential cyclonic vorticity advection will help focus the rain during the day and it will taper in the evening. The coolest day of the week is expected with cloudy skies and a stratiform cooled atmosphere with highs a good 10 degrees below normal with mid 40s and mid/upper 50s over eastern NY and western New England. The rainfall may cause some ponding of water in a few spots. As the column cools overnight a chilly rain will taper. A few wet snow flakes may occur over the southern Greens. Lows will be in the mid 30s to mid 40s. && .LONG TERM /SATURDAY THROUGH TUESDAY/... Unsettled conditions with below normal temperatures looks to dominate much of the long term period, as upper level troughing persists across the Great Lakes/northeast region. Upper level disturbances passing through this trough will bring enhanced chances for showers, which currently looks best on Sunday, however isolated/scattered showers will be possible Saturday as well. The upper level trough will gradually shift east of the region early next week, however an upper level disturbance and associated frontal system looks to track across the region late Monday or early Tuesday with additional rain showers possible. High temperatures will only reach the mid 50s to lower 60s Saturday- Sunday, although could be even cooler if widespread showers occur. Overnight lows mainly in the 40s, with some 30s possible across higher elevations. Gradual warming Monday-Tuesday, with highs reaching the 60s for many areas Monday, and mid 60s to lower 70s Tuesday. Overnight lows in the 40s for Monday and Tuesday morning, although some 30s will be possible across the southern Adirondacks. && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... Through 18z Thursday...Low level stratus clouds have been stubborn to scour out today, with BKN-OVC cigs finally becoming SCT in the past hour at KALB/KGFL/KPSF. So VFR conditions should generally prevail for the rest of the afternoon. A cold front will move across the region later this afternoon. Widely scattered SHRA/TSRA will continue to develop ahead of the front this afternoon. At this time, radar indicating main area for development has been just north/west of KGFL, so will mention a TEMPO for MVFR conditions there. Activity looks to be more sparse at KALB/KPSF, so will mention VCSH for now and monitor trends for possible additional convection. Any SHRA/TSRA should remain north of KPOU. The threat for any SHRA/TSRA should end by early this evening, with dry conditions then expected. Within the developing cold advection regime overnight, an increase in low level stratus clouds may occur. Confidence in coverage/heights is low at this time, with mainly MVFR cigs anticipated. Cig heights should increase to VFR levels Thursday morning, but with BKN-OVC cigs still expected. Winds will become westerly between 18z-19z and increase to around 10-15 kt with gusts around 20-25 kt developing. Winds could also be stronger associated with any TSRA. Winds will become northwest this evening around 6-12 kt, then northerly by early Thursday morning. Outlook... Thursday Night: High Operational Impact. Likely SHRA. Friday: High Operational Impact. Likely SHRA...RA. Friday Night: Moderate Operational Impact. Chance of SHRA. Saturday: Moderate Operational Impact. Chance of SHRA. Saturday Night: Moderate Operational Impact. Chance of SHRA. Sunday: High Operational Impact. Likely SHRA. Sunday Night: Low Operational Impact. Slight Chance of SHRA. Monday: Moderate Operational Impact. Chance of SHRA. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. MA...None. VT...None. && $$ SYNOPSIS...Wasula NEAR TERM...Main/Wasula SHORT TERM...Wasula LONG TERM...KL AVIATION...JPV