textproduct: Burlington

WHAT HAS CHANGED

As of 218 AM EDT Wednesday...

No significant changes to the current forecast.

KEY MESSAGES

As of 218 AM EDT Wednesday...

1. Widespread rain is expected to arrive later this morning and spread east through tonight as winds increase from the south and southwest.

2. A drier period is anticipated to end the week as gusty winds persist Thursday, decreasing toward the weekend.

3. High pressure will bring another stretch of dry and pleasant weather to start the weekend.

DISCUSSION

As of 218 AM EDT Wednesday...

KEY MESSAGE 1: Our next weather system arrives from the Great Lakes mid to late morning as a warm front draped across New York pushes east. Isentropic lift along the warm front will lead to widespread light to moderate stratiform rain on the leading edge of the system late this morning through the afternoon, moving from the St. Lawrence Valley eastward into central and northern Vermont. While the system will be fairly progressive, projected precipitable water values in the latest model runs reach as high as 1.75-2.25 inches. As rain turns more showery towards the later afternoon and evening today, heavy downpours will be possible. Much of central and northern Vermont are currently in D0 (abnormally dry) to D1 (moderate drought) levels, so we are not anticipating hydrological issues from this rainfall. Precipitation totals through early Thursday morning will be highest across the on northern and western slopes of the mountains across our forecast area with around 0.50-1.15 inches anticipated. Lower amounts are likely in the Champlain and Connecticut River valleys due to shadowing from the mountains, closer to 0.20-0.60 inches in these areas. High temperatures today will be seasonable in the lower and mid 70s, so elevated instability is favored over surface, and will likely be competing with the preceding stable air. A few rumbles of thunder will be possible with modest overall instability and strong 40-50 knots of shear. No severe or strong storms are expected across northern New York or Vermont through the end of the week. A strong low level jet of 40-50 kts at 850 mb will also build in this evening, resulting in that shear mentioned. While most of these stronger winds aloft will not be realized at the surface due to concurrent precipitation, gusts between 25-35 MPH are likely, especially in the favored south-north channeled valleys. For mariners, a Lake Wind Advisory is in effect for Lake Champlain today and tonight. Temperatures will remain mild overnight tonight in the upper 50s to mid 60s due to the influx of warmer air in the warm sector of the system.

KEY MESSAGE 2: Widespread mild highs in the 70s are expected on Thursday as gusty winds persist in favorable vertical mixing and drying low levels behind the the system. Winds will likely gust between 20-30 MPH out of the west and northwest Thursday, then trend weaker into Friday but continue to be almost brisk in cold air advection. This will result in a cooler day Friday with highs in the mid 60s to lower 70s. Depending on how light winds can become Thursday night and Friday night, with high pressure nosing in from the Great Lakes during this period, we can expect some patchy valley fog in the typical spots. Deep layer ridging will slide over the region on Saturday, supporting a dry and sunny day after fog dissipates, with high temperatures back in the mid and upper 70s.

KEY MESSAGE 3: High pressure will build into the region towards the end of the week into the weekend, bringing a stretch of dry and pleasant weather. Daytime high temperatures on Saturday and Sunday will climb the 70s to near 80 as the ridging shifts eastward leading to warm southerly flow across the region. While dry weather will persist through much of the weekend, precipitation chances will increase through the day on Sunday with a progressive shortwave trough pushing through. There is still plenty of uncertainty regarding this feature, with some uncertainty regarding how much moisture and widespread shower activity will be, but currently it looks like the better chances will be towards the International Border. Another system looks to bring another round of widespread precipitation Tuesday into Wednesday.

AVIATION /12Z WEDNESDAY THROUGH SUNDAY/

Through 12Z Thursday...VFR conditions currently prevail across terminals this morning, with widespread rainfall expected this afternoon into the overnight hours. As rainfall moves into the region, flight conditions are expected to trend towards MVFR for both ceilings and visibility restrictions, generally after 18Z. Heading into the evening and overnight, steady rainfall will continue to lead to low MVFR and even IFR ceilings, although there is still some uncertainty as to low ceilings will become. In addition to precipitation, breezy south winds are expected to develop later this morning into the afternoon, especially in the Champlain Valley where gusts in excess of 25 knots will be possible. Widespread LLWS is expected across the region towards the end of the forecast period as a strong LLJ moves through the region.

Outlook...

Thursday: VFR. NO SIG WX. Thursday Night: VFR. NO SIG WX. Friday: VFR. NO SIG WX. Friday Night: VFR. NO SIG WX. Saturday: VFR. NO SIG WX. Saturday Night: VFR. Slight chance SHRA. Sunday: Mainly VFR, with local MVFR possible. Chance SHRA.

MARINE

Southerly wind gusts 15 to 25 knots are expected on Lake Champlain this morning by 7 AM to 9 AM, highest across the Broad Waters. Sustained winds will reach 15 to 25 knots around 11 AM to 1 PM today, increasing to 30 knots this afternoon and peaking around 2 PM to 4 PM. Waves will be around 1 to 3 feet, building to 2 to 4 feet. Sustained winds diminish below 25 knots by 1 AM to 3 AM early Thursday morning.

BTV WATCHES/WARNINGS/ADVISORIES

VT...None. NY...None.