weatherwiz

Should see a FROPA sometime end of the week but that may mean storm chances on the 4th or Friday depending on timing.

I do think clouds/morning precip are going to prevent us from achieving the higher end of the instability potential. I would wager we only get up to around 1500 J of MLCAPE (As opposed to 2000-2500). Localized severe still likely but not getting 2000-2500 will prevent severe from being more widespread.

Indeed, sometimes how the morning performs with the warm front can be a solid precursor to how the afternoon will perform, especially when you're talking about instability being on the greater end of the spectrum.

Currently, a northwest to southeast oriented warm front resides from the northern Great Lakes region into Canada southeast across Pennsylvania and into portions of the mid-Atlantic. This warm front accelerates northeast through the remainder of Saturday, advecting in a moisture rich, high theta-e airmass into New England with dewpoints likely into the lower 70's by early Sunday morning. Through the day today, a shortwave trough dives into the upper-Midwest and amplifies as it progresses across the northern Great Lakes region towards the northeast. The result will be unseasonably strong wind shear overspreading the region characterized by 40-45 knots of bulk shear. In addition, winds in the lowest levels of the atmosphere in the wake of the warm front may remain more southerly with winds more west-southerly aloft. Where llvl winds remain more backed, large helicity values in the 0-1km and 0-3km are likely with as much as 150 m2s2 in the 0-1km layer and 150-200 m2s2 in the 0-3km layer. At the surface, temperatures are expected to climb into the upper 70's to lower 80's with dewpoints into the lower 70's (even as high as 73-75°F should dewpoint pooling result). Depending on the extent of morning cloud cover and degree of heating, temperatures, especially in the valley, could soar as high as 83-85. Despite marginal mlvl lapse rates (~6 C/KM), the combination of surface temperatures into the lower 80's and dewpoints into the lower 70's may yield moderate instability characterized by MLCAPE values in the 1500-2000 J/KG range and SBCAPE values around 2000-2500 J/KG. It should be interesting to note some forecast model guidance is suggesting MLCAPE values could approach 2500+ J/KG with SBCAPE values exceeding 3000 J/KG. These values are difficult to obtain without mlvl lapse rates ~7 C/KM and greater, however, if surface temperatures can near 85 and dewpoints climb into the 74-75°F range, these values could become obtained. The combination of moderate instability and strong wind shear ahead of an approaching cold front and likely pre-frontal trough development will be more than favorable for scattered-to-numerous thunderstorms developing by early afternoon and organizing into one or multiple convective lines. This combination of ingredients is also supportive for the strongest thunderstorms to produce locally damaging wind gusts and perhaps even a tornado. There are some caveats, however, which may reduce a more organized severe weather episode from occurring. In addition to the marginal mlvl lapse rates, the strongest shortwave forcing remains displaced well to the west of the best overlap of shear/instability with forecast model guidance showing the best shortwave forcing still in southeast Canada between the mid-to-late afternoon. All in all, the expectation is scattered-to-numerous thunderstorms develop across interior southeast New York by early afternoon with activity quickly organizing into one or more convective lines. Should the more extreme instability scenarios verify (MLCAPE > 2000-2500 J/KG) potential for a more widespread damaging wind producing event will increase. Given the larger helicity values, there would even be potential for an embedded tornado or two. Any tornado potential would be highest with any discrete cells which form initially or out ahead of the line. Localized flash flooding will be a concern as well given PWAT values approaching and exceeding 2''.

Thread for Sunday coming soon

I always love when I see the 3km being aggressive with convection.

Alot of the soundings though show some subtle little warm layers up around 700 and just below 500. But this could be minute if we actually see these CAPE numbers verify with 40-50 knots of bulk shear in place and ~150 m2s2 of 0-1km helicity.

Lapse rates are not great tomorrow but seeing models developing ~2500 J of MLCAPE and ~3000 J of SBCAPE. That is significant stuff, especially given the dynamics. If we realize those numbers severe could certainly be a bit more on the widespread side.

Certainly plausible depending on the timing. But the way the setup looks, I think updrafts will really struggle to become mature. I was looking at a few soundings and the thermal profile is rather wonky. We'll see a line of heavy rain with thunder but cells within the line will be of the pulse variety. Certainly enough shear though, both speed and directionally, that any cell that is able to become mature enough could rotate and produce a tornado. In terms of timing though, I think we end up seeing this slow down a bit (which would increase potential). Front looks to become nearly parallel to the upper flow, an indicator it will slow. Meanwhile, this will increase the potential for flash flooding. This should be the #1 concern.

Awful lapse rates for Sunday but if we can recover after morning stuff there could be a few nasty storms. Dynamics are very strong and the instability would be there should we recover given dews into the 70's. Best forcing is displaced too. Would be looking at some very localized severe potential with potential for a tornado

Working outside and have to move into the Sun. Was too chilly sitting under the overhang with the breeze, especially wearing shorts.

Wish the lapse rates were steeper but the timing has become a bit more favorable in recent runs. Someone going to get porked with rain though given flow alignment.

eh keep these airmasses around and handy. Can't hurt severe weather chances

confirmed TOR yesterday RI intoMA

Saturday should be mainly dry south of the Pike there will be showers/thunder north of the Pike along the edge of the warm front/higher theta-e air. Whenever the timing for the cold front is though, whether it be Saturday night or Sunday, is going to be a deluge out in front of it with PWATS surging > 2''. If bulk of the rain/thunder move through Saturday night, there may be an additional risk for showers/thunder Sunday afternoon with the secondary cold front.

Agreed. At least with timing though there is still some room to improve upon but it at least seems to me a bit of a disconnect between best forcing and instability. Regardless, lapse rate look pretty bad so anything would probably be isolated and pretty localized. I am a bit more worried for FF potential.

Back to shitty lapse rates for Sunday. Lots of questions with that right now, particularly with the timing. Also, looks like the best forcing will be lagging the front a bit and there will be a bit of a disconnect between the greatest shear/forcing and highest instability. Highest instability = south, greatest shear/forcing = north. Anyways, looks like we could remain convectively active moving through the first at least week of July. You just hope we can sneak in a few EMLs in here. It's not a terrible look for EML advection, but one thing I think we're missing is more of a trough at H7 digging into the west.

Within this looks like there was a decently long-tracked supercell across western PA

Also, that has to be the strongest wind gust at BDL since 5/31/98 I would think?

I am still kind of in awe about the BDL wind gust but also very curious. I wonder if that strongest core just happened to go over the station. I didn't do much driving along 75 just because it was super dark and its not well lit. But when I was heading to the highway and went down some roads, I didn't notice any big damage or come across power outages. Might have been a super small, concentrated core. I still can't get over last night though...just the amount of lightning and power flashes.

Snip it of video with the two power flashes just before the winds came. I had to have seen a dozen power flashes tonight

Making the trip back to Springfield. That was epic. Got some video with the power flashes. Will upload to YouTube when I get home. Happy damage all

NE CT has to be getting crushed. Those velocities from BOX seem legit

Insane…the winds were super strong but I would not have guessed that haha. I said to my friend, “I can’t wait to see what BDL got…at least 40 mph”. Thought higher but didn’t want to sound like a weenie. it was crazy…the whole sky in front of us lit up green and then a wall of wind and rain came

67 knots??? WOAHHHHHHHHH LETS FOOKING GO!!! Yesssssss