textproduct: Binghamton

WHAT HAS CHANGED

No major changes to the forecast. Adjusted precipitation and thunder changes for tomorrow, as guidance continues to show a later onset time of strong to severe storms.

KEY MESSAGES

1) Strong to severe storms are expected tomorrow, starting in the late afternoon to evening. The main threat will be strong to damaging winds.

2) The warm pattern through the week will break down late in the weekend, with much colder air arriving in the late weekend, and extending into early next week.

DISCUSSION

KEY MESSAGE 1...

Today will be similar to yesterday, as the area maintains under the ridge flow pattern with shortwaves and MCS' continuing to ride along the ridge. We're currently monitoring the MCS in Michigan, which will be the driver of some early morning convection around sunrise. Ahead of the approaching system, there's a small pocket of CAPE in Western NY that bleeds a little into our western counties for this forecast area. This will likely lead to a line of storms approaching and pushing into the area from the west, but will likely fizzle slowly out as it moves across mainly Central NY and the Twin Tiers.

Going into the afternoon, models continue to show that there will be more CAPE than yesterday (>1000J/kg of surface CAPE) and better shear (>40 knots of 0-6 km shear). If the timing of the mid level wave that triggers the storms is like the current model guidance is showing (in the late afternoon to evening), strong to severe storms are likely, and isolated supercells are possible. SPC maintains a Marginal risk across most of Central NY and NE PA for this potential, with a Slight Risk nearby in Central PA. The main potential threats with Wednesday's storms will be strong to isolated damaging winds, some hail, and training storms bringing heavy downpours that could cause isolated flooding. WPC continues a Marginal Risk for excessive rain, and isolated flash flooding across most of the forecast area for the late afternoon through the overnight hours.

We will still be in this warm SW flow pattern going into Thursday, with frequent shortwaves bringing rainfall and afternoon storms. Better forcing arrives late in the day along an incoming cold front. There is uncertainty in the amount of CAPE that ultimately materializes, but with temperatures back in the mid-70s to low 80s, and dew points in the low 60s, instability could again reach moderate levels (1000 J/kg +). This time period will need to be watched closely as 0-6km shear remains elevated between 40-50 kts once again over the region.

After the cold front pushes through Thursday night into Friday morning, there will be some lingering showers and a chance for a few storms through the day on Friday. However, overall instability and shear are forecast to be much lower on Friday. Temperatures will also come down some, with highs in the mid-60s to mid-70s expected.

KEY MESSAGE 2...

While this warm, early summer-like pattern persist through the first half of the weekend, the late weekend into early next week has continued to trend cooler, thanks to a trough digging into our area. With the Great Lakes likely warming up some over the rest of this week, it is possible they would be warm enough to generate lake effect snow shower activity with this pattern, as temperature differentials exceed 15C from the lake surface up to the 850mb level.

With the anomalously cold air mass in place it appears daytime highs may stay in the 30s to low 40s on Monday. Very cold overnight lows in the 20s are then expected Monday night into Tuesday morning. It then appears a gradual moderating trend will take hold Tuesday into the middle of next week.

As of now, the pattern with the cold is looking dry (outside of lake effect).

AVIATION /06Z WEDNESDAY THROUGH SUNDAY/

Another night with calm winds after some rainfall has led to fog in the area. Most of the Central NY terminals will have off- and-on periods of fog early this morning with Fuel Alt to IFR restrictions. A line of showers and possibly some thunderstorms then moves in from the west around 10z and quickly passes through the region. There is uncertainty if showers will reach AVP with this initial round. There will be a lull in shower activity until late this afternoon. Another round of showers and thunderstorms are expected to move in late in the day and continue well into the evening hours. Isolated storms could become strong to severe with gusty winds and hail. After sunset, thunderstorms should lose their energy but there will be showers lingering around until near the end of the TAF period. With these showers, MVFR to Fuel Alt restrictions are expected. Guidance is hinting at IFR ceilings after 00z at SYR and RME but this forecast caps restrictions at Fuel Alt for now.

Winds have now become calmer. Winds will become gusty after the morning line of showers move through with peak gusts around 20 kts. This update kept higher winds in the forecast as observations in recent days have been higher than forecasted and with an active pattern, there is potential for stronger winds. Then winds calm back down late in the TAF period. Wind direction will vary throughout the day, starting out southerly and becoming more westerly as the afternoon showers move in.

Outlook:

Wednesday Night through Friday...Restrictions possible from showers and isolated to scattered thunderstorms. Early morning fog also possible.

Saturday...Additional restrictions look to arrive along with showers and storms late in the day Saturday.

Sunday...Restrictions possible from showers.

BGM WATCHES/WARNINGS/ADVISORIES

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