textproduct: Binghamton

WHAT HAS CHANGED

A Flood Watch has been issued for Oneida County for Tuesday morning into Wednesday evening. Otherwise, no significant changes were made to the forecast.

KEY MESSAGES

1) Unsettled weather returns tonight and persists through much of the week and possibly into this weekend. Thunderstorms and locally heavy rain will need to be monitored through the week, as this will bring the potential for flash flooding and possibly some minor river flooding.

2) Above normal temperatures are expected through the entire week.

DISCUSSION

KEY MESSAGE 1...

An active weather pattern is expected over the next week. Deep southwesterly flow will bring moisture from the Gulf northward into the Northeast. A nearly stationary front will start to sag southward out of Canada overnight tonight and on Tuesday. This will bring the first period of light to moderate rain showers tonight.

For Tuesday, PWATs will continue to increase to 2+ standard deviations above normal for this time of year. Most of our area will be well into the warm sector south of the front on Tuesday. Model soundings show abundant moisture (PWATs in the 1.0-1.3 inch range). Mid level lapse rates are expected to increase over 7C/km by Tuesday afternoon and evening, however the lower levels will likely remain stable, so MUCAPE values only get to about 500 J/kg due to the stable low levels. While parts of the area are in a Marginal Risk in SPC's Day 2 Convective Outlook, this will be highly dependent on seeing any clearing and daytime heating, because otherwise there will not be enough instability. Right now, the expectation is that morning rain showers and clouds should keep the environment stable. That being said, a convective line of showers and some thunderstorms could still bring some gusty winds to the area late Tuesday afternoon into Tuesday evening. An isolated tornado cannot be ruled out due to the strong winds aloft.

The main concern will be long duration moderate to heavy rainfall rates as the stationary front slowly moves through the area Tuesday through Wednesday. This, combined with the high PWATs for this time of the year, will bring a potential for localized flash flooding. The highest confidence in seeing flooding issues is currently in Oneida County since the rainfall will combine with snowmelt. As a result, a Flood Watch has been issued there and it will be in effect from 8AM Tuesday morning to 8PM Wednesday evening.

Models show the front barely making it into southern PA or the northern Mid- Atlantic by Wednesday evening before it lifts back north a warm front on Thursday. This will bring another round of rain and showers to the area through Thursday night...with yet more rain potential on Friday as the center of the low and eventual cold front press through the area. The latest guidance continues to show the cold front stalling out as it approaches the Mid- Atlantic states due to a strong Bermuda High off the coast. This will open the door for a third system to bring more rain over the coming weekend. Behind this weekend system, a stronger front will should clear out the moisture for a while by the end of the weekend.

There are a lot of variables associated with each of these systems, however the simple fact that each system may stack more and more water across our increasingly sensitive watersheds lends careful watching.

KEY MESSAGE 2...

A nearly continuous warm, moist southerly flow will result in above normal temperatures for the entire week. Highs on Tuesday and Wednesday will likely be in the 60s to lower 70s. Somewhat "cooler" temperatures are expected on Wednesday and Thursday behind a shallow cold front, but temperatures will still be above normal (highs in the lower 50s to to upper 60s). A return to a warm, moist southerly flow will result in temperatures rising once again to the 60s and 70s for Friday and right through the weekend.

AVIATION /00Z TUESDAY THROUGH SATURDAY/

Rain showers have developed across the Southern Tier this evening and will continue to spread to the rest of the terminals by around 6Z. Initially it will take some time for the cigs to drop to MVFR but vis will falter between VFR and MVFR for the first few hours of rain.

After 8Z, there is a chance that thunderstorms develop, mainly in the Southern Tier mainly affecting BGM. ITH, and ELM. SYR and RME have a chance as well but confidence was too low to include with this set of TAFs.

Rain showers persist through much of tomorrow as well, though coverage will be sparser with MVFR cigs but decided to keep showers in the weather group.

Thunderstorms could move in tomorrow late as a cold front moves in, though timing of the cold front is not till after 0Z but if it speeds up, SYR, ITH, and RME may see a wind shift as well as thunder just before 0Z.

Outlook:

Tuesday night through Thursday...a chance of rain showers and associated occasional restrictions possible. Thunder possible each afternoon starting Tuesday afternoon.

Friday through Saturday...Scattered rain showers and low chance for afternoon thunderstorms; associated occasional restrictions possible.

BGM WATCHES/WARNINGS/ADVISORIES

PA...None. NY...Flood Watch from Tuesday morning through Wednesday evening for NYZ009-037.