006 FXUS61 KALY 191134 AFDALY Area Forecast Discussion National Weather Service Albany NY 634 AM EST Fri Dec 19 2025 .WHAT HAS CHANGED... Aside from minor adjustments to reflect latest observations and model trends, no changes were made that would significantly alter the integrity of the previous forecast. Widespread rainfall, becoming moderate to locally heavy at times, and strong wind gusts remain the primary concern over the next twenty-four hours. && .KEY MESSAGES... 1. Widespread rainfall will last through this evening, becoming moderate to locally heavy at times and posing the potential for nuisance urban and poor drainage ponding of water. 2. The potential for isolated rumbles of thunder exists around mid-morning through early afternoon today within a heavy band of rain that will traverse eastern New York and western New England from west to east. 3. Strong south to southeasterly winds through this morning will pose the threat of power outages and potential property damage should trees, tree limbs, and/or wires be downed. Winds will remain strong through late this evening, maintaining this threat, but will instead be blowing out of the west beginning this afternoon. 4. Cold weather swiftly returns tonight, resulting in patchy freezing and subsequent slippery surfaces. 5. The upcoming week features the continuation of an active weather pattern that could impact holiday travel. && .DISCUSSION... KEY MESSAGE 1... A potent surface low pressure system, currently residing in southwest Ontario at a pressure of 982mb, will traverse southeast Canada today beneath a negatively- tilted, upper-level trough. Ahead of the primary, cold frontal boundary associated with the low, a southerly flow regime has inflicted unseasonable and non-diurnal warmth across the region. In fact, high temperatures will occur later this morning ahead of the fropa and could challenge the daily record temperatures at two of our climate sites. See the Climate section below for additional details. An initial surge of warm-advection rain is anticipated to spread into the region from south to north this morning as persistent southerly flow provides an influx of moisture into the divergent, right entrance region of the upper jet. Initially, rainfall rates will be on the lighter side as the strongest forcing remains tightly bound to the cold front. Additionally, this preliminary batch of rain will have to compete with dry air entraining into the leading edge of the upper trough, which can clearly be seen on latest water vapor imagery and within a dry slot on the Northeast Mosaic Radar. By about mid-morning, the aforementioned cold front will be encroaching upon the western boundary of our CWA, bringing with it a rather intense cool-frontal rain band. A very strong axis of frontogenetical forcing, a steep theta-e gradient, omega intersecting a deep moist layer, and LLJ dynamics align with this band, leading latest CAMs to indicate potential rainfall rates of 0.25" to 0.5" per hour. In fact, forecast soundings indicate K indices of around 24-27 which hint at the increased potential for heavy rain. All that said, this will be a very progressive band, as its parent front is also quite progressive. Therefore, it is not expected that heavy rainfall rates will linger over a given area for extended periods of time. Flash flooding is subsequently not anticipated. However, given the moderate to locally heavy rainfall rates at times, especially within the band itself and when the band congeals with the batch of rain ahead of it, there is a potential for localized ponding of water in urban and poor-drainage areas. This ponding will be enhanced by snowmelt from the pre-existing snowpack. Additionally, modest rises, especially small creeks and streams, can also be expected from the same factors. But the progressive nature of the storm will not allow time enough for any main-stem rivers to even flirt with Action Stage. KEY MESSAGE 2... The aforementioned cool-frontal rain band poses a rare, though limited, threat of thunder for late December. Though there is an overall lack of even elevated instability, the potency of the forcing could be sufficient to overcome it. Forecast soundings indicate very strong and deep omega intersecting deep moisture throughout the column. Such rapid vertical motion will lead to rapid cooling. To aid this further, forecast soundings also indicate, for the most part, the strongest omega intersecting the steepest lapse rates within the 850-500mb layer. This will only help to further enhance the rate at which air cools, leading to the expectation that dynamical forcing alone could be the driving factor in some isolated rumbles of thunder within the band. Have therefore included some isolated rumbles along the progression of the band within the forecast. We also mentioned gusty winds as downward momentum transfer from rapid cooling, precipitation loading, and heavy rainfall rates could cause isolated wind gusts whose magnitudes surpass that which is covered by the current wind advisory. KEY MESSAGE 3... South to southeasterly winds will remain in place through this morning before sharply veering to the west in the wake of the cold front this afternoon. According to the latest HiRes models, the 850 mb LLJ will surge to 65-80kt this morning ahead of the cold front, giving surface winds the potential to reach sustained speeds of 15 to 30 mph with gusts up to 50-60 mph. Now, what may hinder this is the low-level inversion that looks fairly prominent on latest forecast soundings compared to previous. However, with precipitation loading, rapid cooling within the column, and steep pressure falls, it is certainly possible for this to be overcome. Once winds veer to the west this afternoon behind the front, rapid cooling and steep pressure rises into late this evening will continue to support strong winds. The new regime will also support downsloping off the higher terrain and channeling down the Mohawk and Hudson Valleys, so confidence is higher in winds reaching the aforementioned magnitudes during this time period. KEY MESSAGE 4... Persistent cold air advection in the wake of the cold front, and eventually the upper-level trough by late tonight, will be supported through the newly-introduced westerly flow regime tonight into Saturday. However, rapidly cooling temperatures will not be met with rapid reductions in wind speeds. With steep pressure rises anticipated through tonight as high pressure slides eastward, winds will remain gusty in most areas. Therefore, despite an overall gradual decline in wind speeds, the probability of a widespread flash freeze is very low as previously wet surfaces could dry out before becoming icy. That said, patches of slippery, icy surfaces will be possible, especially in portions of the Mid-Hudson Valley, Upper-Hudson Valley, and western Adirondacks where the lowest wind speeds are anticipated and where roadways go untreated. KEY MESSAGE 5... Latest medium to long range guidance is hinting at a clipper system that could impact holiday travel later this week. While the system itself appears more robust than in previous runs, there still remains many timing discrepancies between model solutions. That said, the highest probabilities for Advisory- Level (>4") of snowfall are attributed to Tuesday evening, according to the latest NBM, mainly across the higher terrain. However, these probabilities only span 10-25% so confidence remains low in significantly impactful weather at this time. We will continue to keep an eye on it throughout the weekend and provide more details as they become available. && .AVIATION /12Z FRIDAY THROUGH TUESDAY/... Through 12Z Saturday...Widespread MVFR/IFR flight conditions this morning for KALB/KGFL/KPOU/KPSF. There are some LIFR conditions at KGFL where some mist/fog developed. The warm front lifted northward across the region and is near the_I-90 corridor with an area of light to locally moderate rainfall. A lull in the steadiest pcpn may occur between 13Z-15Z/FRI before the cold front approaches from the west with a narrow cold frontal rainband with perhaps a rumble or two of thunder. PROB30 groups were used between 15Z-18Z/FRI for the TAF sites with IFR vsbys and IFR/LIFR cigs with gusty southwest to west winds 25-45 KT. In the wake of the front, lingering MVFR conditions will persist in terms of cigs/vsbys with light rain showers or a mix at KPSF. Expect conditions to rise back to VFR between 21Z/Fri and 00Z/SAT with cigs rising to 3.5-5 kft AGL with the winds increasing in the wake of the cold front and the tightening sfc pressure gradient. KPSF may carry an MVFR cig around 3 kft AGL until midnight. Widespread VFR conditions at all sites after midnight. LLWS will remain a problem until about 18Z/Fri at all the TAF sites. The 2 kft AGL winds associated with the low-level jet will be 50-60 KT with the sfc winds generally less than 5-15 KT at times. The LLWS will decrease in the wake of the cold front with deeper mixing occurring. The winds will be south to southeast at 5-15 KT early this morning, then increase to 10-20 KT towards 14Z/Fri with gusts 25-40 KT. Winds quickly switch to the west in the wake of the front at 12-20 KT with gusts of 25-35 KT with the stronger gusts at KALB and PSF. Towards 00Z/Sat and thereafter the winds will enhance from the west at 15-25 KT with gusts 30-42 KT with the strongest gusts at KALB/KPSF. The winds will gradually subside between 06Z-09Z Sat from the west/northwest 10-15 KT with some gusts still 20-30 KT. Outlook... Saturday Night: No Operational Impact. NO SIG WX. Sunday: Low Operational Impact. Breezy. NO SIG WX. Sunday Night: Low Operational Impact. Breezy. NO SIG WX. Monday: No Operational Impact. NO SIG WX. Monday Night: Moderate Operational Impact. Chance of SHSN. Tuesday: High Operational Impact. Likely SHRA...SHSN. && .CLIMATE... Record High Temperatures for December 19th: Site: Record High (Year): Forecast High Today: KGFL 52 (1895) 49 KALB 54 (1895) 55 KPOU 60 (1931) 54 && .ALY WATCHES/WARNINGS/ADVISORIES... CT...Wind Advisory until 1 AM EST Saturday for CTZ001-013. NY...Wind Advisory until 1 AM EST Saturday for NYZ032-033-038>043- 047>053-058>060-063>066-082>084. High Wind Warning until 1 AM EST Saturday for NYZ054-061. MA...High Wind Warning until 1 AM EST Saturday for MAZ001-025. VT...Wind Advisory until 1 AM EST Saturday for VTZ014-015. High Wind Warning until 1 AM EST Saturday for VTZ013. && $$ DISCUSSION...37 AVIATION...15 CLIMATE...37