textproduct: Burlington

WHAT HAS CHANGED

As of 341 AM EDT Tuesday...

Have removed Grand Isle county from the winter weather advisory and lowered ice accretion totals in the advisory area as well. Temperatures are still in the 40s across the region, therefore not expecting as much freezing rain.

KEY MESSAGES

As of 413 AM EDT Tuesday...

1. Round 1 of rain with wintry mix near the international border Tuesday into Wednesday.

2. Round 2 of Rain with wintry mix near the international border Thursday into Friday.

3. River rises expected with local lowland field flooding possible Tuesday into Wednesday.

4. Warm conditions likely Friday through Sunday with periods of gusty winds possible.

DISCUSSION

As of 413 AM EDT Tuesday...

KEY MESSAGE 1: A low pressure system tracks west to east across our area today somewhere in the vicinity of the international border. We are mainly expecting light rain as this low moves across the area along a stalled out front which is bisecting the region. Overnight minimum temperatures have not dropped lower than the 40s, therefore not expecting freezing rain this morning. As temperatures cool this evening there will be a chance for some light freezing rain, generally up to a couple hundredths of an inch. Rainfall totals will range from around six tenths of an inch up to an inch and a quarter through Wednesday afternoon when the precipitation will wind down. There is some elevated instability in place, therefore can't rule out a few rumbles of thunder, and also some rain being heavy at times. Best chances for thunder will be across our southern zones.

KEY MESSAGE 2: Another storm system tracks across the region for late Thursday into Friday. Canadian high pressure will be established on Thursday and it will provide a cold antecedent airmass for this low pressure to run into. With the current expected storm track, the precipitation looks to start as a wintry mix and transition to all rain. Areas east of the Greens will have the best chance of seeing some ice accretion where there will be some cold air damming on the east side of the mountains. This system will also only have small ice accretions, up to two hundredths of an inch. Winds will be gusty behind this system as it pulls away to the east, southerly gusts around 30 kts are possible.

KEY MESSAGE 3: Combination of the two rain systems this week will provide us with one to two inches of QPF. There will also be some snow melt as temperatures remain mild through the period. Combination of these factors will mean we could see some sharp rises on area rivers and streams. At this time think that we will mainly see within bank rises, but some gages could reach action stage mid week.

KEY MESSAGE 4: A higher amplitude upper level pattern becomes probable over the weekend as a trough digs over the northern Plains states. This pattern should keep the storm track to our west with lower chances for precipitation than earlier in the week. The flow pattern will also maintain the persistent ridge over the western Atlantic and the associated warm air over much of the eastern US. As such, unseasonable warmth, which has occasionally surged northward, should become more sustained in our area. High temperatures could be well into the 60s to low 70s Friday through Sunday.

As of now, both Friday and Sunday look fairly similar with regards to gusty south winds. The ECMWF Extreme Forecast Index is also fairly bullish on high temperatures being quite warm on Sunday ahead of the system's cold front, particularly in the Champlain Valley and southern portions of our New York forecast area. However, an earlier timing of the front will support Friday and Saturday being more likely warmer days despite this potential warmth. Based on the 00Z ensemble data, the slower frontal timing seems to be dominated by the ENS over the GEFS/GEPS, so think things may trend towards a faster frontal passage and a less warm scenario for Sunday, although morning temperatures would be unusually mild. Gusty post frontal, westerly winds will be possible regardless sometime in the later Sunday-Monday period as temperatures fall back towards normal early April values.

AVIATION /12Z TUESDAY THROUGH SATURDAY/

Through 12Z Wednesday...Rain showers have become more widespread, resulting in a trend towards mainly MVFR conditions with very brief IFR visibilities in any heavier showers. A lull in rain is expected at all terminals later this morning before rounds of widespread showers arrive this evening and overnight. Moist conditions combined with convergent flow patterns will lead to increasing chances for low ceilings and IFR conditions even as steady rain ends, especially in northern terminals. Rain may also have embedded thunderstorms this evening, although probabilities are too low to mention in TAFs. Greatest risk of thunder would be in southern terminals including SLK, RUT, and MPV.

Winds will be somewhat changeable based on the wavering position of a front bisecting the airspace. At northernmost terminals, expect mainly light northerly flow, although MSS continues to have gustier northeast winds than other sites as typical in these patterns. Winds will tend southerly at MPV and RUT, but also light. These surface winds will be accompanied by bursts of stronger southwesterly winds aloft as clusters of showers move through the area, especially after 22Z, resulting in areas of low level wind shear at BTV, SLK, and RUT primarily.

Outlook...

Wednesday: Mainly VFR, with local IFR possible. Slight chance RA, Slight chance FZRA. Wednesday Night: VFR. Chance FZRA, Chance PL, Slight chance SN. Thursday: Mainly MVFR, with areas VFR possible. Likely RA, Chance FZRA, Chance SN, Chance PL. Thursday Night: Mainly MVFR, with local VFR possible. Definite RA, Chance TSRA, Likely FZRA. Friday: Mainly MVFR, with local IFR possible. Chance RA. Friday Night: Mainly MVFR, with local IFR possible. Chance RA. Saturday: Mainly VFR, with areas MVFR possible. Chance RA.

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...Winter Weather Advisory from 8 PM this evening to 9 AM EDT Wednesday for NYZ026>028-030-031.