textproduct: Burlington

WHAT HAS CHANGED

As of 551 AM EDT Sunday...Updated forecast to increase areal coverage of snow shower activity with mention of likely pops acrs the SLV and western Dacks. Crnt radar and sfc obs indicate light snow is falling with vis btwn 1-4SM in many locations acrs northern NY. This should lift out of the area by 14z with just a dusting to 1 inch of snow accumulation expected.

Confidence has increased slightly in some isolated to scattered light rain showers Monday afternoon and evening. Tuesday's high temperatures are trending downwards due to moisture, rain potential, and cloud cover. Temperatures are now projected to be in the 40s to mid 50s except a few spots in the Connecticut River Valley potentially reaching near 60 Tuesday afternoon. Confidence increases for the mid week system to have mainly rain as its precipitation type.

KEY MESSAGES

As of 239 AM EDT Sunday...

1. Temperatures warm above seasonal averages through midweek.

2. The next storm system will move through the region Tuesday into Wednesday, bringing widespread rain and strong southerly breezes.

3. Active pattern prevails late week with a wintry mix of precipitation possible.

DISCUSSION

As of 245 AM EDT Sunday...

KEY MESSAGE 1: Temperatures will be gradually increasing through the midweek. Southerly flow develops today, kicking off warm air advection and bringing surface temperatures back to around seasonal averages, generally in the 40s this afternoon with quiet weather today and perhaps a couple light rain showers Monday. High temperatures continue increasing into the upper 40s to mid 60s through Wednesday for most locations, though guidance has come in a touch cooler than previous forecasts for Tuesday's highs. Overnight lows will also see a gradual warming over the next few nights with temperatures Sunday night as low as the upper 20s and 30s, likely becoming upper 30s to lower 50s by Tuesday night. Tuesday night and Wednesday temperatures will largely depend on the timing of a cold frontal passage, so stay tuned for future temperature forecasts.

KEY MESSAGE 2: Our next chance for appreciable precipitation this week will be Tuesday into Wednesday as a frontal system tracks into the region. Most models continue to indicate a frontal boundary setting up across the Canadian border on Tuesday. Confidence has increased for precipitation type to be in the form of mainly rain as temperatures climb into the 40s and 50s in the warm sector of the storm, and there could even be some rumbles of thunder across northern New York Tuesday afternoon/evening. However, some higher elevation and northern spots could have some quick snow at the onset of precipitation Tuesday morning. Temperatures should fall Tuesday night, but not below freezing, so rain remains the main precip type. However, uncertainty remains on the timing of a cold frontal boundary crossing the area, so the potential for precip to change briefly to snow is not out of the question. Tuesday night also features the modeled peak in precipitable water values at around 1.10-1.40 inches, and guidance continues to suggest slow/training motion vectors likely. This coincides with the timing of both the surface low pressure tracking along/just north of the Canadian border and a strong low level jet up to 55-65 knots at 850mb passing over northern New York and Vermont early Wednesday morning. Model blends are indicating about 10-40% chances of an inch of precip occurring in 24 hours Tuesday and Tuesday night. Forecast precipitation totals Monday night through Tuesday night are around 1.00-2.00 across northern New York, northern Vermont, and the spine of the central/northern Green Mountains. In parts of central and southern Vermont, between 0.40-1.00 is anticipated. Winds will be gusty Tuesday night into Wednesday morning, shifting from south- southwesterly to northwesterly by the end of the day Wednesday. While the rain will likely stabilize the atmosphere for much of the time the jet is screaming overhead, there could be lulls and dry slots during this period (particularly Tuesday night and Wednesday morning), potentially resulting in very gusty surface conditions. Precipitation should come to a brief pause Wednesday night before the next system returns steady precip to the area late week.

KEY MESSAGE 3: Still a large spread in latest guidance with regards to late week system and potential impacts acrs our fa. Latest WPC forecast indicates cooler temps for Thurs/Fri with highest probability of precip during this time frame. The current WPC forecast shows pops in the 60 to 70% range, but prob of measurable precip in a 24 hour period is near 100%, which indicates high chance precip wl occur and relatively good agreement in guidance. The primary issue is the placement of boundary separating very warm air to the south and much cooler air to the north, supplied by retreating arctic high pres. Latest 00z GFS has trended cooler with a slight southward shift in high pres, resulting in cooler sfc to 925mb temps acrs our central/northern cwa. This solution would suggest a greater probability of mixed precip, with some ice accumulation possible over the northern SLV/CPV and parts of the NEK. Given the very sharp thermal boundary progged to be somewhere acrs the mid Atlantic/NE CONUS on Thurs into Friday, have adjusted the ptype grids to mention just rain or snow at this time. This wl need to be fine tuned when higher res data is available. Also, have left WPC temps for now, but they are likely to change as event becomes closer. Highs generally in the mid 30s to mid 40s with lows upper 20s to mid 30s for late week, before a warming trend develops by next weekend.

AVIATION /12Z SUNDAY THROUGH THURSDAY/

Through 12Z Monday...A warm front is lifting across northern NY into central/northern VT this morning with scattered snow showers. A few heavier returns have produced localized IFR VIS at SLK/MSS. This will move northeast of MSS/SLK by 14z this morning with VFR conditions prevailing at all sites. Gusty southwest winds develop behind this boundary with localized gusts up to 25 knots expected between 15z and 22z today. Winds weaken around sunset with areas of low level wind shear likely at MSS/SLK and RUT this evening.

Outlook...

Monday: VFR. Slight chance SHRA. Monday Night: Mainly VFR, with areas MVFR possible. Chance RA, Slight chance SHRA. Tuesday: Mainly MVFR, with local IFR possible. Definite RA. Tuesday Night: Mainly MVFR, with local IFR possible. Definite RA. Wednesday: Mainly MVFR, with local IFR possible. Chance RA. Wednesday Night: Mainly VFR, with areas MVFR possible. Chance RA, Slight chance SN. Thursday: Mainly VFR, with local MVFR possible. Chance RA, Slight chance SN.

EQUIPMENT

The Colchester Reef meteorological station is out of service. This site is not serviced by the NWS. An estimated return to service is May 1st. Please contact us if you observe winds significantly deviating from the recreational forecast.

BTV WATCHES/WARNINGS/ADVISORIES

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