Area Forecast Discussion

WHAT HAS CHANGED

No significant changes to the forecast with this update. Added in some PoPs for a few showers tonight into Wednesday morning as a weakening warm front runs into the strong upper level ridge; precipitation amounts will be very light if it does occur.

KEY MESSAGES

1) High pressure remains in place with an upper level ridge building through Wednesday keeping the region mainly dry and gradually warming into mid week.

2) The ridge begins to flatten in the eastern US with a more active pattern on Thursday. Showers and a chance for thunderstorms will be in the forecast.

3) Dry weather looks to return Friday into Saturday as the flow turns northerly and pushes the shower activity further south into the Mid-Atlantic. It then turns more active Sunday into early next week as the next upper level trough and associated frontal system moves in from the west.

DISCUSSION

KEY MESSAGE 1...

It will be clear and cool this morning with areas of fog as the 1028mb surface high sits overhead. Expect plenty of sunshine today, with perhaps just a few high clouds streaming through late morning and early afternoon. Winds turn south and increase through the day, becoming breezy by this evening at 8-15 mph with gusts to 20-25 mph over the Finger Lakes and surrounding locations. After the cool start it should warm up nicely into the upper 60s to mid-70s this afternoon around the region.

A decaying warm front tries to press in from the northwest, but runs into the massive 594dm ridge over the area. Model guidance is hinting at some more cloud cover and perhaps a few light showers or sprinkles overnight into Wednesday morning, especially north of the NY Southern Tier. Most of Wednesday will be dry as well, but can't rule out a stray showers along the weak frontal boundary. There will be more clouds north and more sun south through the day. Winds remain out of the south-southwest and decrease through the day, eventually turning west-northwest late in the day along the I-90 corridor. High temperatures range from the mid-70s to low 80s across the area, and humidity levels increase by afternoon.

KEY MESSAGE 2...

A weak low pressure system then moves through the area on Thursday. It will remain warm and humid with dew points near 70 expected. There will be modest amounts of instability, especially across the Southern Tier and NE PA. PWATs will be anomalously high, between 1.75 to 1.95 inches over the area, this is about 2.5 standard deviations above normal for this time of year. This setup will bring the potential for efficient rain producing showers and a few thunderstorms. There will be the potential for some heavy downpours and a low risk for excessive rainfall amounts. There does remain plenty of uncertainty on just how much instability will be present on Thursday, so this will impact the potential for any organized convection; which if it does materialize could bring gusty winds and even higher rainfall rates. The trends will need to be monitored closely in the coming days. Otherwise, Thursday looks to be mainly cloudy, and very humid with highs in the mid-70s to low 80s again.

KEY MESSAGE 3...

High pressure slides toward the region across southern Canada Thursday night into Friday. Confidence appears to be increasing in the latest model guidance that this will turn winds northerly for our area, and bring in a drier air mass. The NBM ensemble guidance now has Friday completely dry, and mostly sunny with low humidity and seasonable high temperatures in the 70s. Most of Saturday also looks dry in the latest ensemble data, but a late day warm front could bring a low chance for showers over northern portions of Central NY. Temperatures trend down a few degrees compared to Friday.

The latest guidance is also starting to come together on a more consistent solution for the end of the upcoming weekend and early next week. The models are showing a more active weather pattern as a series of lows and waves move along a stalled frontal boundary along the northern periphery of the Southeast ridge. This will keep more clouds and showers in the forecast, especially on Sunday...but could linger into at least Monday. High pressure does try to move back in from the north by next Tuesday, but confidence is low this far out in time in the exact position of this feature. Temperatures look to be seasonably cool in the time period, with low to mid 70s on Sunday fading into the 60s for highs by Monday/Tuesday. Overnight lows are expected to be in the 50s Sunday night, then potentially falling back into the 40s Monday/Tuesday nights.

AVIATION /06Z TUESDAY THROUGH SATURDAY/

Conditions will be mainly VFR this TAF period. The exception will be with the development of valley fog at ELM. IFR to LIFR restrictions are expected. Beginning around the mid morning hours, southerly winds will become stronger and gusty. Peak gusts up to 20 kts will be possible at the central NY terminals.

Outlook...

Tuesday Night through Wednesday...Mainly VFR.

Thursday...Scattered showers and thunderstorms may result in occasional restrictions, especially in the afternoon.

Friday...Mainly VFR.

Saturday...Scattered rain showers and associated occasional restrictions possible.

BGM WATCHES / WARNINGS / ADVISORIES

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