textproduct: Binghamton

WHAT HAS CHANGED

Gusty south winds 25 to 40 mph develop after midnight and into Friday morning, especially across the Finger Lakes and hills south of Syracuse. Temperatures and dew points trending a little cooler on Saturday, reducing rate of snow melt and reducing any flooding potential even more.

KEY MESSAGES

1) Periods of rain in the forecast Friday and Saturday. Expecting a lot of snow melt and any river ice will likely break up. Flooding is not expected.

2) Cool down, back toward seasonable temperatures early next week. Chances for snow showers and minor lake effect return mainly Sunday night.

3) Quiet, seasonably mild and partly sunny weather on tap for early next week. Next clipper and cold front by Wednesday into next Thursday. Colder weather to potentially follow.

DISCUSSION

KEY MESSAGE 1...

Very little change in the forecast for our first system. Low pressure tracks across the central Great Lakes tonight into Friday. The low passing to our west will bring a warm southerly flow to our area. A warm frontal boundary will settle over the area on Friday with periods scattered showers expected. Rainfall amounts will be light, generally less than a tenth of an inch for most locations. High temperatures surge well up into the mid-40s and even some lower 50s. The increase in moisture and temperatures will melt a good deal of the snow pack. This frontal boundary stalls and washes out just east of the area Friday night. Some modestly cooler air may gradually work into the forecast area from NW to SE overnight, with lows in the 30s for Central NY, and mid-30s to lower 40s in NE PA. Little if any rain is expected Friday night as dry slot and subsidence inversion settles overhead by early Saturday morning.

The next low develops over the Tennessee Valley Saturday morning, then tracks toward New York City Saturday night, before dragging a stronger cold front through the area on Sunday. Steady rain is likely to breakout over the area on Saturday and continue into Saturday night; before shifting east late at night. Right now guidance is pointing toward rainfall amounts between about quarter and three-quarters of an inch, with localized amounts around 1 inch in NE PA.

Temperatures and dew points are trending lower on Saturday due to a more southerly low track, with the primary low way back west near Lake Superior and the secondary low (as mentioned above) near NYC Saturday afternoon. This will potentially keep more of an easterly to east-southeast flow of cooler air wedged into the area. Therefore temperatures were lowered, with highs now expected to be in the upper 30s to lower 40s, except mid-40s in the Wyoming Valley. However, temperatures should be above freezing as precipitation moves in Saturday afternoon, so removed any mention of freezing rain due to warm ground surface and delayed onset of rainfall.

It is still likely that nearly all the snow currently on the ground will melt for the lower elevations south of the lake effect areas. Current data shows generally a trace to 1.5 inches of snow water equivalent, with pockets of 2 inches of SWE noted across the Catskills and higher elevations of the far northern Susquehanna Region in Central NY. 1 to 2 inches of SWE exists across Onondaga and Madison counties at this time. Oneida county has more, with widespread 2 to 3 inches of SWE, locally 3-5 inches across the southern Tug Hill region of the county (i.e. Boonville, Woodgate, Point Rock and Florence area).

At this time no major hydro issues are anticipated, but certainly ponding of water in low lying areas and rises on area creeks and rivers are plausible. Forecast ensembles are showing low chances to reach minor flood stage at Conklin, Cortland and Sherburne of around 10 to 15%. However, these are the only sites even showing anything close to minor flood stage at this time and any widespread flooding is unlikely.

KEY MESSAGE 2...

Very little change to the forecast this period. A potent cold front swings through the region Sunday morning, with the upper level trough settling overhead Sunday afternoon into Sunday night. Temperatures will turn much cooler, back closer to seasonable levels for this time period. Northwest winds also become breezy and gusty, likely 10 to 20 mph, with gusts of 25 to 35 mph expected. Official forecast went well above the latest NBM guidance and was based more off the deterministic guidance, along with forecast collaboration with neighboring Weather Service Offices. Some scattered snow showers and lake effect snow showers are expected to develop later on Sunday and into Sunday night, before quickly diminishing Monday morning.

Increased PoPs this timeframe across the I-90 corridor, as NBM was not picking up the lake effect snow very well. At this time, any accumulations are forecast to be light.

KEY MESSAGE 3...

The cool down will also be short-lived, as the trough flattens into a zonal flow pattern with temperatures returning back to being several degrees above normal Tuesday and Wednesday next week. The next clipper system looks to bring a cold front through the area sometime Wednesday or early next Thursday, perhaps bringing a return to more normal mid winter temperatures by the end of next week.

AVIATION /00Z FRIDAY THROUGH TUESDAY/

VFR conditions are expected to continue through Friday morning before ceilings begin to lower to MVFR to Fuel Alternate Friday afternoon as scattered rain showers move in. There will likely be window for IFR ceilings at KBGM late Friday afternoon into the early evening. While guidance is hinting at IFR ceiling restrictions during the same timeframe at KAVP, this is unlikely with a south-southeast downsloping flow.

LLWS is expected to develop at all terminals beginning early Friday morning and likely lasting through most of the day. LLWS will initially be 35-45kts, but will increase to 45-55kts by the mid-morning.

Outlook...

Friday night...Any remaining rain showers ending early, but lingering MVFR to Fuel Alternate restrictions likely at the Central NY terminals.

Saturday through Saturday night...Restrictions likely with rain showers, mixing with snow showers late Saturday night.

Sunday...Possible restrictions with scattered rain and snow showers, especially at the Central NY terminals.

Monday through Tuesday...Mainly VFR.

BGM WATCHES/WARNINGS/ADVISORIES

PA...None. NY...None.