textproduct: Buffalo

SYNOPSIS

High pressure will build across the Ohio Valley and provide dry weather today. A weak cold front will then bring a chance of a few spotty showers tonight and Thursday. A better chance of rain will arrive later Friday as a warm front approaches the area. The front will then stall across the southern Great Lakes Friday night through the weekend, bringing another stretch of unsettled weather with occasional showers and possibly a few thunderstorms.

NEAR TERM /THROUGH TONIGHT/

High pressure centered over the Ohio Valley will maintain dry weather today, although a weak warm front may produce an isolated shower east of Lake Ontario through midday before exiting to our east this afternoon. Gusty southwesterly winds will develop again this afternoon and persist into the evening hours as a tightening pressure gradient along with a strengthening low level jet moving over the area ahead of an approaching cold front will support 30-40 mph gusts across the Niagara Frontier, with 20-30 mph gusts elsewhere.

Aforementioned cold front sags through the area tonight, with the chance for a few light showers/isolated rumble of thunder east of Lake Ontario this evening, with just a very small chance for a light shower elsewhere through the second half of tonight. Gusty southwest winds will continue into this evening just ahead of the cold front, then veer west and lessen in the wake of the frontal passage.

SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/

A west to east oriented cold front will stall across the area for the entire period, generally remaining between northern PA and Lake Ontario. The front will oscillate north/south, generally between the NY/PA line and Lake Ontario as weak disturbances track along it. The front is sandwiched between an area of high pressure to the north and an area of high pressure off the southeast coast.

Precipitation for the period will remain mostly scattered into Friday afternoon as the forcing along the front isn't overly impressive. Moisture does increase some, helping with the potential for afternoon showers and a few thunderstorms for both Thursday and Friday.

The potential for showers will start to increase on Friday afternoon and into Friday night. This will occur as both moisture and forcing along the front increases as two shortwave troughs approach the region, one from a larger trough over the mid-Mississippi Valley and the other from the Upper Great Lakes. The greatest potential for showers and a few thunderstorms will remain dependent on the location of the stalled front and the track of the shortwave troughs.

Temperatures for the period are very much likely to change as guidance comes into better agreement for the placement of the stalled cold front. Daytime highs though, will generally range from the upper 60s to near 80 from north to south.

LONG TERM /SATURDAY THROUGH TUESDAY/

Unfortunately, unsettled weather will again be the theme next weekend as a frontal zone remains stalled from the southern Great Lakes to southern New England. A slow moving southern stream trough crossing the Mississippi Valley will maintain a persistent southerly feed of moisture into and across the frontal zone. A number of low amplitude mid level shortwaves will move through the mean WNW Flow across the Great Lakes, while the low level frontal zone will provide persistent low level forcing. These features will maintain a good chance of showers and possibly a few thunderstorms Saturday through at least Sunday. Some guidance tracks a sfc high through the region fairly quickly on Monday, providing a break in the showers. This is then followed by another cold front that will track across the region Tuesday/Wednesday, increasing the potential for showers and thunderstorms once again. Plenty of uncertainty in the long range among guidance from Monday morning on.

Temperatures will remain relatively cool through the weekend as the eastern Great Lakes likely stays on the cool side of the stalled frontal zone. A warming trend will begin to develop early next week, especially as a sfc high moves through the region.

AVIATION /08Z WEDNESDAY THROUGH SUNDAY/

High pressure ridged north across the area will maintain widespread VFR conditions today, with areas of mainly mid level decks found over the area this morning, although a brief period of low VFR CIGS (~040 kft @ KART) will be possible east of Lake Ontario before a weak warm front presses east of the area this afternoon. More notable will be the gusty southwesterly winds that will develop this afternoon and persist into the evening hours. A tightening pressure gradient along with a strengthening low level jet moving over the area ahead of an approaching cold front will support 30-35 knot wind gusts across the Niagara Frontier (KBUF/KIAG) over to KROC, with 20- 25 gusts elsewhere.

As mentioned above, gusty winds will continue into this evening before the aforementioned cold front sags through the area tonight with winds veering west and lessening in its wake. The front will bring the chance for a few light showers/isolated rumble of thunder east of Lake Ontario this evening, with just a very small chance for a light shower elsewhere through the second half of tonight. Otherwise, VFR conditions will persist, with just a period of low/mid cloud as the cold front sags south through the region.

Outlook...

Thursday...Mainly VFR with a small chance of a few showers and an isolated thunderstorm.

Friday...Mainly VFR with a chance of showers and isolated thunderstorms, mainly later in the afternoon.

Saturday through Sunday...Areas of MVFR with showers likely and a slight chance of thunderstorms.

MARINE

Light southwest winds will continue to produce a light chop on Lake Erie and Lake Ontario through mid morning. Southwest winds will become stronger today as the pressure gradient tightens in advance of an approaching cold front, with near Small Craft Advisory conditions developing on Lake Erie and Lake Ontario during the afternoon and evening.

Choppy conditions will persist on Lake Ontario through Thursday as west winds remain elevated in the wake of the cold frontal passage, before a weak cold front moves south across the lakes Thursday night. Light to moderate northeast winds will develop in the wake of this cold front later Thursday night and Friday, with these northeast winds continuing through this weekend producing choppy conditions much of the time.

BUF WATCHES/WARNINGS/ADVISORIES

NY...None. MARINE...None.