TalcottWx Posted July 17, 2019 Share Posted July 17, 2019 Looks like some sunshine is trying to push in to most of SNE... Link to comment Share on other sites More sharing options...
CoastalWx Posted July 17, 2019 Share Posted July 17, 2019 Feel like this will be one of those nrn RI to SE MA gully washers. Link to comment Share on other sites More sharing options...
TalcottWx Posted July 17, 2019 Author Share Posted July 17, 2019 Just now, CoastalWx said: Feel like this will be one of those nrn RI to SE MA gully washers. Yes, some severe warnings south of pike. I think training right along the pike. Link to comment Share on other sites More sharing options...
TalcottWx Posted July 17, 2019 Author Share Posted July 17, 2019 I'd be surprised if we do not see a severe watch considering the slight designation. As long as the sun breaks out. Looks like it will. Link to comment Share on other sites More sharing options...
TalcottWx Posted July 17, 2019 Author Share Posted July 17, 2019 Mesos have a strong signal for flooding N RI, ORH on East and perhaps into BOS, mostly SW of BOS. Link to comment Share on other sites More sharing options...
weatherwiz Posted July 17, 2019 Share Posted July 17, 2019 10 minutes ago, sbos_wx said: I'd be surprised if we do not see a severe watch considering the slight designation. As long as the sun breaks out. Looks like it will. I don't think we'll see a watch today...or we shouldn't anyways. These are not setups which are prone to producing severe weather...at least on a large enough scale. The degree of sun is also a small factor IMO in these setups...it's more of a factor to enhance likelihood of parcels being able to reach the LFC but it isn't a huge factor in severe weather potential. All instability today is low-level...that's why SBCAPE is quite high. This is due to rich llvl moisture and the warming sfc temperatures...this again will help with getting parcels to LFC. The bigger issue though is what happens above the LFC. Very poor mlvl lapse rates and moist tropospheric profile mean there is very poor instability aloft..."tall skinny CAPE"...this can be seen by meh MLCAPE. As parcels rise above the LFC they will do so but not very rapidly or aggressively...this limits updraft strength. Wind fields are not very strong, but just sufficient enough to yield some updraft organization and the orientation of the flow will organize updrafts into a linear fashion...and as you mentioned a training fashion. Given rather warm temperatures aloft and poor instability not only will lightning production not be prolific but the overall look favors extremely heavy downpours and flash flooding. With warming sfc temperatures you'll develop an inverted-V signature and this would locally promote the potential for a wet microburst. DCAPE values though didn't seem overly impressive on soundings and that is likely a reflection by the saturated look up to the EL. Link to comment Share on other sites More sharing options...
TalcottWx Posted July 17, 2019 Author Share Posted July 17, 2019 3 minutes ago, weatherwiz said: I don't think we'll see a watch today...or we shouldn't anyways. These are not setups which are prone to producing severe weather...at least on a large enough scale. The degree of sun is also a small factor IMO in these setups...it's more of a factor to enhance likelihood of parcels being able to reach the LFC but it isn't a huge factor in severe weather potential. All instability today is low-level...that's why SBCAPE is quite high. This is due to rich llvl moisture and the warming sfc temperatures...this again will help with getting parcels to LFC. The bigger issue though is what happens above the LFC. Very poor mlvl lapse rates and moist tropospheric profile mean there is very poor instability aloft..."tall skinny CAPE"...this can be seen by meh MLCAPE. As parcels rise above the LFC they will do so but not very rapidly or aggressively...this limits updraft strength. Wind fields are not very strong, but just sufficient enough to yield some updraft organization and the orientation of the flow will organize updrafts into a linear fashion...and as you mentioned a training fashion. Given rather warm temperatures aloft and poor instability not only will lightning production not be prolific but the overall look favors extremely heavy downpours and flash flooding. With warming sfc temperatures you'll develop an inverted-V signature and this would locally promote the potential for a wet microburst. DCAPE values though didn't seem overly impressive on soundings and that is likely a reflection by the saturated look up to the EL. Haha, yes- you nail it. I'm with you on every point you typed. I don't have stats to back it up, but just feels like SPC is more prone to throwing out watches when we are in slight area. One thing I will say- there is some solid MLCAPE on some of the mesos. Seems restricted to Eastern areas. Link to comment Share on other sites More sharing options...
Damage In Tolland Posted July 17, 2019 Share Posted July 17, 2019 Noyes thinking rip n destroy Link to comment Share on other sites More sharing options...
Cyclone-68 Posted July 17, 2019 Share Posted July 17, 2019 Feels more like a Florida severe weather day than say a Great Plains severe day assuming anything happens Link to comment Share on other sites More sharing options...
TalcottWx Posted July 17, 2019 Author Share Posted July 17, 2019 3 minutes ago, Cyclone-68 said: Feels more like a Florida severe weather day than say a Great Plains severe day assuming anything happens It's a no doubter. Clouds are breaking. If I fart too loud, CU will form. #downpours Link to comment Share on other sites More sharing options...
weatherwiz Posted July 17, 2019 Share Posted July 17, 2019 15 minutes ago, sbos_wx said: Haha, yes- you nail it. I'm with you on every point you typed. I don't have stats to back it up, but just feels like SPC is more prone to throwing out watches when we are in slight area. One thing I will say- there is some solid MLCAPE on some of the mesos. Seems restricted to Eastern areas. Well it's not just the SPC...they'll collaborate with local offices when it comes to the issuance of watches. There may be a small area where shear/instability are maximized and could have a localized concentration of severe but don't think it will be too widespread. Link to comment Share on other sites More sharing options...
Baroclinic Zone Posted July 17, 2019 Share Posted July 17, 2019 84/73 Link to comment Share on other sites More sharing options...
dryslot Posted July 17, 2019 Share Posted July 17, 2019 Stay safe!! Link to comment Share on other sites More sharing options...
TalcottWx Posted July 17, 2019 Author Share Posted July 17, 2019 A ton of bubbling TCU over NY State heading east. We'll see storms fire ahead of that and then eventually that line over NY (wherever it ends up) will be potential for sig flooding. Link to comment Share on other sites More sharing options...
Torch Tiger Posted July 17, 2019 Share Posted July 17, 2019 ml lapse rates are absolutely awful Link to comment Share on other sites More sharing options...
TalcottWx Posted July 17, 2019 Author Share Posted July 17, 2019 It's like Florida out there Link to comment Share on other sites More sharing options...
Damage In Tolland Posted July 17, 2019 Share Posted July 17, 2019 We watch Link to comment Share on other sites More sharing options...
TalcottWx Posted July 17, 2019 Author Share Posted July 17, 2019 92/71 at Logan. Sheesh. Link to comment Share on other sites More sharing options...
dendrite Posted July 17, 2019 Share Posted July 17, 2019 MMK up to 95/71 Link to comment Share on other sites More sharing options...
TalcottWx Posted July 17, 2019 Author Share Posted July 17, 2019 Just now, dendrite said: MMK up to 95/71 We rarely clear out like this, for this long, in a tropical airmass. Seems like it's always 30 minutes then a downpour. Timing today is quite good. Link to comment Share on other sites More sharing options...
TalcottWx Posted July 17, 2019 Author Share Posted July 17, 2019 PVD, 86/75... #Swamp Link to comment Share on other sites More sharing options...
Modfan Posted July 17, 2019 Share Posted July 17, 2019 1 hour ago, sbos_wx said: It's like Florida out there Similar but different! I'm in Delray Beach and it's 92F with a nice sea breeze; probably no breeze up there. Link to comment Share on other sites More sharing options...
TalcottWx Posted July 17, 2019 Author Share Posted July 17, 2019 1 minute ago, Modfan said: Similar but different! I'm in Delray Beach and it's 92F with a nice sea breeze; probably no breeze up there. Definitely better in Southie, gusting into the 20s on the water. Here at the office in Dorchester, it's pretty insufferable outside... Enjoy that breeze! And the Pool! And the beach! I can't wait until I can live down there lol. Link to comment Share on other sites More sharing options...
dendrite Posted July 17, 2019 Share Posted July 17, 2019 4 minutes ago, sbos_wx said: PVD, 86/75... #Swamp WST 87/79 PVD 85/77 now Was just 82/77 at UUU. Dew of 77 at HVN. Link to comment Share on other sites More sharing options...
TalcottWx Posted July 17, 2019 Author Share Posted July 17, 2019 Lot of strikes out of cell traveling due east near Belchertown. Flash Flood Watch posted regionwide. Link to comment Share on other sites More sharing options...
TalcottWx Posted July 17, 2019 Author Share Posted July 17, 2019 Last two runs of HRRR don't see to have a great handle on what is going on right now. 3k NAM looks like it has more of a clue, comparatively. Link to comment Share on other sites More sharing options...
TalcottWx Posted July 17, 2019 Author Share Posted July 17, 2019 Mesoscale Discussion 1500 NWS Storm Prediction Center Norman OK 1203 PM CDT Wed Jul 17 2019 Areas affected...portions of the Mid-Atlantic and Northeast Concerning...Severe potential...Watch possible Valid 171703Z - 171930Z Probability of Watch Issuance...60 percent SUMMARY...Storm coverage will increase in the coming hours and storms will move east-northeast across the Mid-Atlantic and Northeast along and east of the Appalachians. Damaging wind is the main severe threat with these storms, and a severe thunderstorm watch issuance is possible. DISCUSSION...An upper-level shortwave trough is currently moving over the Great Lakes and into the Mid-Atlantic and Northeast per satellite imagery. Forcing for ascent is spreading downstream of this trough helping to initiate storms across the Appalachians. Ahead of the cloud cover, surface temperatures have already warmed into the 80s F with dewpoints mostly in the 70s resulting in MLCAPE of 500-2000 J/kg. Storms will develop as areas reach their convective temperatures and along a weak pre-frontal trough that is focusing surface convergence south-southwest across the region with building Cu already on visible satellite imagery. Flow through the vertical layer is marginal, but effective bulk shear of 25-35 knots is expected this afternoon/evening that will result in isolated supercells. Overall, the storm mode will be mixed given the strong upper-level forcing, forecast 2000-3000 J/kg of MLCAPE, and marginal shear. Upscale growth is possible with these storms and any QLCS or supercell could pose a damaging wind threat. Link to comment Share on other sites More sharing options...
TalcottWx Posted July 17, 2019 Author Share Posted July 17, 2019 124 PM EDT Wed Jul 17 2019 ...FLASH FLOOD WATCH IN EFFECT UNTIL 11 PM EDT THIS EVENING... The National Weather Service in Boston/Norton has issued a * Flash Flood Watch for portions of northern Connecticut, Massachusetts, and Rhode Island. * Until 11 PM EDT this evening. * Numerous showers and thunderstorms are expected to develop during the mid to late afternoon hours and continue into the evening. The stronger thunderstorms will be capable of producing torrential rainfall with localized rainfall amounts exceeding 2 inches in just an hour. This will result in the potential for localized flash flooding, particularly if this were to occur in an urban center. Link to comment Share on other sites More sharing options...
TalcottWx Posted July 17, 2019 Author Share Posted July 17, 2019 Severe watch is about to go live. Link to comment Share on other sites More sharing options...
TalcottWx Posted July 17, 2019 Author Share Posted July 17, 2019 3 minutes ago, sbos_wx said: Severe watch is about to go live. And away we go... Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now