textproduct: Binghamton

WHAT HAS CHANGED

No major changes from the previous forecast were made at this time.

KEY MESSAGES

1) A cool and wet pattern will continue through much of the weekend. Cold temperatures and light winds will lead to widespread frost later tonight into Sunday morning.

2) Temperatures will trend warmer early next week though frontal systems will bring chances for more widespread rain, especially later Tuesday into Wednesday.

3) Temperatures then fall back below normal for the second half of the work week, and the pattern will remain unsettled.

DISCUSSION

KEY MESSAGE 1...

Scattered showers will be tapering off from west to east across the area early this morning, with most, if not all, the shower activity ending close to daybreak. A few places in the higher terrain of CNY may see some wet snowflakes mix in prior to the rain coming to an end. There is plenty of low-level moisture lingering through the early morning hours with the mid-levels drying out shortly before daybreak. This suggests that clouds may be slower to clear and there may be just a small window with enough breaks around the Finger Lakes for some patchy frost to form prior to daybreak as winds will be light during this time. Temperatures will be in the 30s across much of the area early this morning with the Wyoming and Delaware River Valleys a little warmer in the lower 40s.

An upper level low remains southeast of Hudson Bay later today with a deepening trough over the Mississippi River Valley pushing east. This along with persistent west to northwest flow will keep cool, Canadian air streaming over the region into Sunday.

With cold air aloft, additional instability showers are expected to pop up this afternoon and evening. However, with drier air in place at the surface on model soundings, any showers are expected to be isolated in nature. In fact, the NBM keeps conditions dry through the afternoon and evening, but the CAMs and some of the global models have been consistent in showing some isolated activity, especially around the Finger Lakes and NE PA. Highs will range from the upper 40s to the mid 50s.

The deep upper trough will continue toward the eastern seaboard tonight while surface high pressure begins to build in from the west. With the northwest flow around the high, clearing skies and that cold air still being able to push south with the upper trough, the ingredients are all there for effective radiational cooling. Overnight lows drop into the upper 20s and low 30s, with some mid 30s around some of the immediate Finger Lakes and in the Wyoming Valley. A Freeze Watch is in effect for Luzerne and Lackawanna Counties, and headlines are likely around the Finger Lakes after the current Frost Advisory tonight expires.

KEY MESSAGE 2...

Temperatures trend closer to average on Monday with the return of southwesterly flow and a more zonal pattern aloft. Highs Monday will climb into the 60s with just a slight chance of a shower as some ripples of energy embedded in the flow aloft move through. A deepening upper trough over the Upper Midwest Tuesday will lead to stronger warm air advection ahead of the associated cold front, sending high temperatures into the upper 60s to mid 70s. Overnight lows Monday and Tuesday nights return to the 40s and 50s.

Showers and embedded thunderstorms along and ahead of the cold front are expected starting Tuesday, especially later in the day and continue into Wednesday as the front slowly pushes east and eventually stalls. There remains some uncertainty though with regards to the arrival time of precipitation and where exactly the front stalls out and for how long Wednesday and possibly into Thursday. If rain can make it into the area Tuesday afternoon, that looks to be the best chance for any thunder with the GFS and Euro showing 500-1000 J/kg of MUCAPE this far out with 30 to 40 knots of shear. The GFS shows decent low-level lapse rates and mid-level lapse rates of 6 to 7 C/km, so it's something to keep an eye on.

KEY MESSAGE 3...

The aforementioned cold front slowly inches eastward Thursday. A low pressure system eventually develops along this front and finally pulls the front out of the region as the low curves back over northern New England. Wrap around moisture will keep chances for precipitation around through Friday. To add to the unsettled pattern, temperatures will fall back below normal with highs mainly in the 50s Thursday and Friday and with overnight lows in the 30s and 40s.

AVIATION /06Z SATURDAY THROUGH WEDNESDAY/

Restrictions with low stratus ceilings and patchy fog early this morning, however, drier air starts to move in around sunrise and ceilings are expected to be mainly VFR from mid morning onwards.

Outlook:

Sunday through Monday... Mainly VFR, but restrictions will be possible at times in isolated to scattered showers.

Tuesday...Scattered showers and associated restrictions possible.

Wednesday...Restrictions possible from rain showers and thunderstorms.

BGM WATCHES/WARNINGS/ADVISORIES

PA...Freeze Watch from this evening through Sunday morning for PAZ044-047. NY...Frost Advisory until 9 AM EDT this morning for NYZ015>018.