National Weather Service Buffalo NY
441am EDT Sat August 10 2024
Synopsis
In the wake of Debby's remnants it will be cooler and drier today. An upper level trough will bring unsettled weather tonight through Monday with lake effect rain showers downwind of the lakes, and general scattered showers and isolated thunderstorms during Sunday. After this high pressure will build in, bringing a return to fair and seasonably warm weather for Tuesday and Wednesday.
Near Term - Through Tonight
A closed upper level low will spin just northeast of Lake Superior, which will continue to usher in a cooler air mass. Weak surface high pressure will offset this with dry air in the boundary layer keeping today mostly rain free. There could be some lake effect and diurnal cumulus, but it will otherwise be dry outside of perhaps an isolated shower. It will be breezy with gusts 30 to 35 mph across the Niagara Frontier. Highs will range from the upper 60s to mid 70s.
The upper level low will move closer tonight with the axis of its trough moving into the Central Great Lakes. 850mb temperatures around +8C will be cool enough to support lake effect rain showers when combined with synoptic moisture associated with this trough. Some uncertainty when these will get going, but the most likely time is during this evening. SSW flow will direct these east/northeast of the lakes, with a bit more activity expected off Lake Ontario due to the greater moisture available. Otherwise, fair weather outside of lake effect rain showers. A light breeze will limit radiational cooling, but lows will still drop into the 50s due to the cooler air mass.
.SHORT TERM /SUNDAY THROUGH TUESDAY NIGHT/... A mid-level closed low gyrating north of the Great Lakes will slowly meander east over the rest of the weekend. With H850 temps in the single digits (+8C/+9C) and some level of synoptic moisture wrapping back into the region lake effect showers will 'likely' be found northeast of both lakes Sunday morning. As we transition into the afternoon the incoming trough axis combined with diurnal effects will lead to scattered to numerous showers developing inland from the lakes. Showers will then transition back to mainly lake effect rain showers off the lakes Sunday night. With enough lake induced instability in place...a few embedded thunderstorms could develop within the lake effect rain showers.
Overall...Sunday looks like it will be the coolest day of this period. Highs will range from the 60s to the low 70s. Lows Sunday night will generally be found in the 50s by daybreak Monday.
The mid-level low will continue to ever so slowly pass by to our north Monday as it tracks towards New England. Again...lake effect showers in the morning east and southeast of the lakes will transition to some diurnally-driven showers or even a thunderstorm inland from the lakes in the afternoon. As we progress into the evening we should see convection begin to diminish as drier air works into the eastern Great Lakes.
Highs on Monday will be found in the 60s to low 70s again.
Monday night...high pressure building into the region will bring about a quiet and dry weather for most locales. Lows will generally be found in the 50s.
.LONG TERM /WEDNESDAY THROUGH FRIDAY/... Surface based ridging will generally bring quiet and dry conditions for most locales during this period. That said...with the trough lingering overhead and subtle features moving through, a few isolated showers or storms may Probability of Precipitation up during peak heating each day. Given the difficulty in timing and placing these features this far out...have held Probability of Precipitation in the slight-chance range for now.
Otherwise temperatures will recover back to around normal...with daily highs climbing back to the mid 70s to lower 80s for Wednesday through Friday...and nightly lows warming to the mid 50s to lower 60s.
Marine
Moderately brisk westerlies will more or less continue across the Lower Great Lakes through the weekend. This will promote SCA (Small Craft Advisory) conditions into Sunday night. With a favorably cool environment in place aloft, any lake effect rain showers will have the potential to produce waterspouts on the lakes. Waterspouts tend to form on boundaries.
NOAA Buffalo NY Office: Watches - Warnings - Advisories
NY...Beach Hazards Statement through this afternoon for NYZ001- 005>007-010-019-085.
Marine
Small Craft Advisory from 11am this morning to 8pm EDT this evening for LEZ020. Small Craft Advisory until 11pm EDT Sunday for LEZ040-041. Small Craft Advisory until 2am EDT Monday for LOZ042- 043. Small Craft Advisory until 5am EDT Monday for LOZ044-045.
