purduewx80

A little surprised the Gulf disturbance doesn't have higher probs. At the least this is going to be a flooding concern in the Houston area as the developing low gets trapped under the ridge for 2-3 days.

it escapes, moot at this point though.

seeing a quick increase in low-level winds on the local dopplers, too. TJFK showing ~45MPH at 1500-2000'.

been a few storms just S of LI all morning, wouldn't be surprised to see a rogue lightning strike or two around this afternoon as the upper jet amplifies in the perfect spot for lift

I think that's more of a downburst over the harbor. TJFK is on the lower right portion of the image, so it doesn't really indicate rotational shear.

add another to JFK's 75+. currently 81/75.

slower dorian + deeper lakes s/w. definitely worth watching next few runs.

there've been a few out there today.

Noticing the 12Z ECMWF is starting to hint at that. I think its worth watching trends the next 48-72H for a possible capture. Would be much more concerned if I were on Cape Cod or Nova Scotia.

have to watch winds on the eastern end of the island. vis sat suggests to me the inverted trof will be located somewhere in suffolk later this afternoon into the evening. if winds shift SE then some localized severe is possible, including brief spin-ups. these are legit convective showers moving in. tops estimated 35-38000' on the heaviest cells. inch/hour+ rates seem likely for brief periods across all of LI.

hands down the best storm of the summer here in terms of low vis/wind and rain rate, even if it was 10-15 min.

500/700mb winds increase pretty quickly 21-22Z on the latest RAP. Mid-level lapse rates were excellent on the 12Z IAD sounding but poor around here. That area is forecast to shift this way during the afternoon. Dry air is the main inhibitor to better instability this afternoon. First area to watch will be northeast PA along the front - most guidance kills those off as they move off the mountains to the SE towards us...maybe a slight chance here as early as 5-6PM. Energy back in Ohio now will arrive this evening, so the higher storm chances in the city are probably like 8-11PM.

yeah, i think so. looks like an evening/overnight event for the most part. instability is lower than today but shear is fcst to be considerably stronger.

doesn't take storms hitting the terminals to throw up some major delays. usually the airlines will start considering cancels for thunderstorms when delays are 2+ hours.

A lot of guidance showing the same thing this evening, except dew points may not recover until tomorrow night. Might not see JFK make it to a Td of 75 tomorrow, but it's looking more likely that Thursday stays humid w/ the slower advance of cooler/drier air.

One of the nice things about the SPC soundings is that they show the max mid-level lapse rates, which may not always correspond to the standard 700-500mb levels. Both IAD and OKX sampled lapse rates above 7C/km this morning. In fact, they're steep from ~950 up to ~600mb. The warmer temps at 500mb are what's keeping 700-500 rates much lower. Despite the fcst modest shear, this is a decent signal for some strong winds this afternoon: Convection should pop pretty quickly near and just west of the city by 2-3 this afternoon.

Yeah, that was the 2nd most interesting thing about those storms for me yesterday. Didn't take long to recover overnight, though. There was a lot of cloud-to-air lightning with the cells near the city yesterday afternoon and 1 "bolt from the blue" here in BK. Haven't seen that in awhile.

meanwhile, the south shore beaches are foggy.

Could see a couple storms over central/western LI next 2-3 hours before the seabreeze shifts farther inland. Nice convergence over the middle of the island now.

Can probably add Sun-Wed to that, possibly Thu if the front slows at all.

Mesoscale details are always fickle. I think this was a good lesson for non-mets not to trust a small-scale feature's exact placement more than 12 hours ahead of time. Convective feedback played havoc w/ the MCV/low placement. That and the widespread clouds are what kept things in check around here and I don't think it was totally obvious until early Tuesday AM.

maybe try planting some native grasses so you don't waste so much water.

Exactly, there are a lot of mesoscale details to sort out, including a yet-to-develop vort over Colorado this evening that is forecast to survive into our area Tuesday PM. We were barely able to crack 2" on PWATs last Wednesday and most guidance has them upwards of 2.3-2.5" Tuesday; the low-level jet will be stronger w/ this system as well.

OKX AFD describes Tuesday's potential nicely: SPC has us in the marginal risk (slight just to the SW) for severe - mentioning a risk for supercells somewhere nearby. The WPC has us in a slight risk for excessive rainfall/flash flooding.

agreed. another surface low taking ~direct aim at us. this one will have much better shear (50KT mid-level jet) and moisture than last week.