textproduct: Binghamton

WHAT HAS CHANGED

Lowered temperatures slightly on Thursday and Friday given expected rain and cloud cover. Lowered precipitation chances for Thursday afternoon and evening as model guidance is too varied at this time.

KEY MESSAGES

1) Temperatures are expected to uptick as the week progresses, with well above normal highs and lows expected through the end of the work week.

2) Multiple systems are expected to move across the region this afternoon through Friday, bringing rain and thunderstorm chances. Some of the thunderstorms could be severe Wednesday through Friday.

DISCUSSION

KEY MESSAGE 1...

The axis of the ridge that has brought nice weather to the area the past few days has slid east of the area. This has allowed SW flow to return that will pump warm, moist gulf air into the region. Temperatures will top out in the mid to upper 80s across the Finger Lakes into the Mohawk Valley as the first signs of the southern airmass make their way into the region. The rest of the area will remain in the low 80s.

We will start to feel the effect to of the more moist airmass on Wednesday as dewpoints climb into the mid 60s by late morning. Morning showers and cloud cover should keep temperatures in the mid to upper 80s across most of the region. Higher terrain east of I-81 will remain in the low 80s.

Temperatures Thursday and Friday will climb into the mid 80s to low 90s, increasing to the upper 80s to mid 90s on Friday. The warmest temps are expected to be in the valleys of the Twin Tiers, but with dewpoints expected to be in the mid to upper 60s, heat indices will rise into the low to mid 90s on Thursday and mid to upper 90s on Friday. Some uncertainty remains with temps on Friday as a cold front is expected to move into the area and its timing will have a large impact on temperatures. It currently looks like it will pass through during the afternoon hours, but it will depend on how the incoming trough interacts with the ridge to the east. Heat advisories may be needed.

Temperatures will fall back to near normal to slightly above normal for the weekend and into next week.

KEY MESSAGE 2...

With the ridge axis moving east of the area and flattening out, CNY and NEPA will return to an active weather pattern through the rest of the work week.

A amplified shortwave trough is moving across OH into WNY this afternoon, pushing a warm front into the area and developing some rain showers and thunderstorms along the periphery of the high that is sliding eastward. Scattered showers and storms are expected to move across the northern Finger Lakes and into Oneida county starting late this afternoon and into the overnight hours. Storms are not expected to be severe as instability and shear are lacking, but heavy downpours will be possible as PWATs will be around 1.5in.

Wednesday will see increased CAPE as the warm front will have fully pushed through the area. A low pressure system moving out of the Great Lakes to the NE will be the main weather driver for the day. The associated trough axis will slide through the area during the afternoon hours. The lift provided by the trough will combine with afternoon CAPE values between 1500-2000 j/kg and low level lapse rates of 7-8C to kick off scattered thunderstorms in the afternoon, with some having the potential to be severe. Currently, a lack of shear is holding back the potential for more widespread severe storms, but with PWATs in the 1.75-2in range, rain driven downdrafts could cause damaging winds. Hail will also be possible, although the lack of updraft organization should keep hail sizes on the low end. Areas hit by slow moving storms or hit by multiple storms could see isolated flash flooding.

Wednesday night, our attention turns to the potential for a MCS moving into the region from the Great Lakes. Models have been showing varied paths of the MCS, with some even having it dissipate before it moves into the area as it hits high pressure. This variance is pretty normal for this set up as the positioning and strength of the ridge will guide the path of the system. We are tracking the possibility of an elevated mixed layer (EML) moving overhead during overnight hours, keeping CAPE high and shear modest. If the ELM can be realized, an MCS should develop and ride the edge of the ridge over our area. Timing and location still is uncertain.

With the possible rain from the MCS moving through the area either Wed night or Thurs morning, the atmosphere is modeled to become capped in the low levels during the day on Thursday. Elevated convection will still be possible during the afternoon, and if an area is not impacted by morning rain and can see some clearing, an isolated severe storm cannot be ruled out.

A cold front is expected to push through the area Friday afternoon. Lift from the front combined with CAPE values approaching 2000 j/kg and modest 0-6km should kick off thunderstorms, some severe, along the front as it pushes through. Timing of the front will be the main severe weather driver for Friday. Many models are starting to show an afternoon passage, but given there is a sharp, narrow ridge propagating across the area ahead of the front, the timing could change based on interaction with the ridge. PWATs will also be high so heavy downpours and isolated flash flooding could be an issue.

The weekend should be mostly dry and seasonable as we will sit between a ridge to the south and a trough to the north. Active weather returns Sunday afternoon thru most of next week as we will be under a large upper level trough that will throw multiple shortwaves through the area next week.

AVIATION /00Z WEDNESDAY THROUGH SUNDAY/

Mostly VFR expected through at least 10Z early Wednesday morning at all terminals. A few showers and thunderstorms have developed this evening across western NY and the Finger Lakes region of Central NY. These storms are moving slowly off to the north and east. Included a tempo group at SYR and RME for some MVFR showers as they gradually weaken and move through or near these terminals between 00-05z. Right now the t'storm activity is forecast to remain just north of ELM and ITH; but will be monitoring this closely and make amendments if storms do deviate toward these two terminals prior to 03z.

After 10Z, a warm front lifts in with cigs falling to MVFR or MVFR Fuel Alt areawide. MVFR CIGs may eventually scatter some heading into the afternoon hours, with breaks of sun, but for now confidence was not high enough in any scattering or breaks to include in the tafs.

Rain showers and potential thunderstorms start to form close to 19z, potentially lasting until 23z or so. Highest chance seems to be across the SYR and RME corridor, so included PROB30 groups for TSRA here.

Outlook:

Wednesday night through Friday Night...Scattered showers and thunderstorms may bring occasional restrictions, especially each afternoon.

Saturday into Sunday...Cold front moves through with VFR conditions likely, potential fog at ELM overnight.

BGM WATCHES/WARNINGS/ADVISORIES

PA...None. NY...None.