textproduct: Binghamton

WHAT HAS CHANGED

Upgraded the extreme heat watch to a warning for Wednesday through Friday.

KEY MESSAGES

1) Heat and humidity becomes unhealthy and dangerous in some areas for the rest of this week.

2) Several rounds of scattered thunderstorms could occur through the week and into the weekend. Severe weather and locally heavy rainfall and flooding will be possible within the favorable warm and humid conditions.

DISCUSSION

KEY MESSAGE 1...

A extreme heat warning has been issued for the entire region with significant changes to the model guidance and forecast temperatures. Temperatures in the upper 90s and even a few 100 degree reading will be possible in the urban valleys across the region. The only caveat will be the potential for convection over the coming days that could ease the heat. Today, we are seeing this happen with remnants of an MCS this morning providing clouds over central NY and limiting heating, and another complex dropping out of southern Ontario this afternoon that will further limit heating.

Weds- Thurs are looking like the hottest days of the week, with enough of the sensitive demographic areas (cities and deep valleys) still within the crosshairs of extreme heat criteria in the 105 to 110 degree range. Friday will be a little cooler, but likely the urban area could still see 105 degree heat indices.

KEY MESSAGE 2...

Ring of fire weather pattern over the coming days as we will be close to the periphery of the upper ridge. Several embedded perturbations associated with prior upstream convection will be the kickers as they round the upper ridge. Our fate on thunderstorms will depending on how strong and amplified the ridge becomes this week.

For today, a severe thunderstorm watch is looking likely across portions of central NY as a strong MCS is dropping out of Ontario, Canada early this afternoon. Strong damaging winds will be the main threat with this MCS, but can't rule out an isolated tornado and hail as well. Also, although portions of the region are in a Marginal risk for severe thunderstorms on Wednesday, it is possible that this area gets expanded upon and could turn into a slight risk, as the upper ridge may level out some tomorrow. Surface based CAPE values are well outside the norm for the Northeast over the next couple days and shear is sufficient to develop and maintain severe weather. Excessive rainfall is also possible with diffluent thickness fields over our area angling back toward the moisture axis surging in from the Ohio Valley. Upstream MCS turning through the Great Lakes over the ridge like we are seeing this afternoon could be the story over the coming days, so multiple rounds of thunderstorms will be possible. Due to the extreme instability for this region, even lasting into the nighttime hours, the potential for a long lasting MCS or Derecho exists for somewhere in the Northeast U.S. in the coming days, but at this time, it is not possible to pin down timing or location, but this will be something to monitor.

Forecasters will be monitoring upstream thunderstorm complexes over the coming days and confidence will increase for severe weather when we see a long lived MCS pushing across southern Ontario, Canada, such as the case today.

Some relief appears on the horizon after Thursday as the flow aloft turns more westerly and then pivots into more of a flat trough for the weekend which should bring increased cloud cover, some cooling and more unsettled showery conditions.

AVIATION /18Z TUESDAY THROUGH SUNDAY/

A cluster of thunderstorms moving through northern NY is expected to reach RME and skirt SYR for about 30 minutes or so at each terminal. It is expected to bring a heavy, but brief, bout of rain and strong gusty winds. Winds upstream at KART have gusted 45 to nearly 50 mph and the strongest part of the storm looks to pass over northern Oneida County and very close to RME.

Once this cluster goes through, there can be additional showers or thunderstorms that pop up into this evening, especially along any outflow boundary and TEMPO groups for thunderstorms have been added to ITH and BGM to go along with the severe thunderstorm watch.

Later tonight is expected to be mainly VFR although ceilings do lower. MVFR or lower restrictions can't be ruled out for a time prior to daybreak, especially around RME, ITH and ELM. Winds become westerly toward the end of the TAF period tomorrow with the chance of seeing additional scattered showers and thunderstorms developing.

Outlook:

Wednesday afternoon through Sunday...Mostly VFR, but intermittent restrictions will be possible with isolated to scattered showers and thunderstorms each afternoon.

CLIMATE

Current High Temperature Records:

6/30: BGM - 92 (1964), SYR - 94 (1971), AVP - 97 (1964) 7/1: BGM - 90 (2018), SYR - 94 (2018), AVP - 95 (2018) 7/2: BGM - 92 (1966), SYR - 96 (1963), AVP - 98 (1966)

Forecasts for 7/1 and 7/2 are at or near the daily records.

BGM WATCHES/WARNINGS/ADVISORIES

PA...Extreme Heat Warning from 11 AM Wednesday to 8 PM EDT Friday for PAZ038>040-043-044-047-048-072. NY...Extreme Heat Warning from 11 AM Wednesday to 8 PM EDT Friday for NYZ009-015>018-022>025-036-037-044>046-055>057-062. Heat Advisory until 8 PM EDT this evening for NYZ015>018- 022>025-036-037-044-045-055-056.