textproduct: Binghamton

WHAT HAS CHANGED

PoPs were increased today and tomorrow, mainly for northeast PA. Higher end PoPs were capped at 70% with scattered coverage expected with the multiple rounds of showers and storms today.

KEY MESSAGES

1) Showers and thunderstorms return today with potential for isolated strong storms and heavy rainfall.

2) The pattern will remain relatively active this week with brief periods of dry conditions in between passing systems.

DISCUSSION

KEY MESSAGE 1...

A weak wave will move into western NY and PA early this morning and eventually into central NY and northeast PA by day break. Sky cover will begin to increase just ahead of this system with isolated showers expected during the morning hours. All of this should limit any instability, so while thunderstorms cannot be ruled out, they should remain sub-severe. After this moves through, there will be some breaks in cloud cover and conditions will become warm and humid by the afternoon. Instability will climb to 1000 to 2000 J/kg of MLCAPE and 0-6 km shear will be 30 to 40 kts, though some model solutions are showing lower shear values. This will occur ahead of remnants of a MCS that moves into the region this afternoon with isolated to scattered thunderstorms. Given the enhanced instability and shear values, there will be potential for strong to severe thunderstorms later today and into the evening hours. The main hazard would be gusty winds. Some model soundings show CAPE through the hail growth zone and while lapse rates are not particularly steep, hail will also be possible. Low-level shear looks to be too weak for any spin ups. PWATs will be around 1.75 inches though storms should move along today. Still, one dry day likely has not been enough to dry out the ground, so localized flash flooding cannot be ruled out.

For this system, PoPs were capped at 70% as there is uncertainty if the line will hold together as it moves through or be more broken. The CAMs are split on this as coverage looks to be more scattered. There is the chance that some areas do not see a drop of rain today. PoPs were also increased across northeast PA as guidance kept this region dry this morning, though if the line currently in western PA holds, rain is to be expected here.

Prior to the showers and storms moving through, temperatures will rise into the upper 70s to mid 80s. It will be humid though as dew points will be in the upper 60s to low 70s. Overnight, temperatures will be fairly mild, only falling into the 60s. With calming winds, breaks in cloud cover, and added moisture from today's showers, patchy fog will be possible in the valleys.

KEY MESSAGE 2...

A ridge out west and broad troughing in the east will favor a fairly active pattern this week. Ridge riders will pass over the Great Lakes Region and pass near or over our region. Weak high pressure and drier air will build into the region the night prior though a weak system will likely clip the Southern Tier and northeast PA on Tuesday with passing showers and thunderstorms. NBM guidance was not picking up on this, possibly lagging behind newer guidance, so Consall was blended in to bump up PoPs. Wednesday is expected to be mostly dry as well

Late in the week, the upper level trough begins to dig slightly and leads to the next system moving in Wednesday night into Thursday. High pressure then follows to bring another dry period late in the week and to start the weekend. A weak low pressure then moves through Sunday with another batch of showers that may linger into the start of next week.

There is quite bit of uncertainty with each system mentioned above, especially late in the week and over the weekend. Models continue to differ on exact tracks and timing, which impacts the coverage. There is confidence that there will be dry periods and not any particular day is expected to be a wash out.

Temperatures will trend cooler during the later half of the week. Highs will be in the 70s to low 80s. Temperatures overnight will fall into the 50s.

AVIATION /12Z MONDAY THROUGH FRIDAY/

Mainly VFR conditions are expected across the region today, before showers and thunderstorms arrive this afternoon and evening.

It seems the first round of showers and TSRA arrives around 18/19z in the west and spreads east by 20/21z. Continued with PROB30 groups, time adjusted, for showers at RME and SYR. further south included PROB30 groups for thunderstorm potential (MVFR) at ELM, BGM, ITH and AVP.

After 00z there may be some scattered showers around still in the vicinity of most taf sites. Otherwise, after a brief VFR period, widespread MVFR/IFR stratus clouds are forecast to develop over the area for early Tuesday morning, with patchy fog also possible.

Light southeast to east winds early this morning turn southwest and increase by late morning and afternoon. Winds will be between 6-12 kts with a few higher gusts possible. The west-southwest winds diminish after sunset, back down to around 5 kts.

Outlook:

Tuesday through Thursday...Unsettled pattern with periods of showers and scattered thunderstorms with associated restrictions. Restrictions with overnight fog/low clouds are also possible.

Friday...Returning to VFR.

BGM WATCHES/WARNINGS/ADVISORIES

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