vortex95

That's quite good for 12z, esp. the CAPE!

If you are confused, you are not alone. While I understand what SPC is trying to do here (quantify risk better), it not easy or always intuitive (probabilities and statistics are are tough subject for many, or kind of dry)! If mets and wx enthusiasts have problems figuring this out this, forget it as to the general public! It somewhat reminds me of interpreting the homograph, it not intuitive at first you have to spend time on what you are looking at and think in 3-D despite looking at a 2-D plot!

Good to know. Thanks!

Highest gust on record for the summer set in July 1996, correct? They had PL at the time IIRC. And I think this same storm system resulted in record flooding in Quebec.

Coldest I could find outside mtn location in New England is 47 at Fox Brook ME.

Recall during the Olympics in China, the smoke pollution was never called such? You would get official statements like, "it is mist" or "it is getting ready to rain."

I agree it is not as bad as 2018, but when you talking tenths of deg when it comes to exceeding records, it does matter, and the longer the period, the more this drift is a problem when talking avg temps. 1 F bias does not sound like much for a single day, but it is big over the course of a month, and keeps increasing the longer you go.

If it thick enough, it does. Put it this way on an ideal radiation cooling night, if there was a layer of thick smoke at 20,000 ft, do you really temps woild drops as low as if there was no smoke? Yes, the SW/LWIR physics are not the same as WV clouds, but it is still a cover, so to speak. Why did BOS only hit 90 on 7/14 when 97 was fcst?

Today it was DC's turn for thick smoke. VIS at KDCA got as low as 1.25 mi and VV restriction of only 200 ft! METAR KDCA 171252Z 00000KT 1 1/2SM FU VV020 28/17 A3007 RMK AO2 SLP183 T02780167" CoastalWx, remind you of doing TAFs for India? Every night, the VIS like clockwork would drops big time to 1/4 mi or less from smoke at so many airports, not from wildfires, but industrial pollution.

600 dm heights/ridges can and are misleading as to heat. It depends on many factors, like one's relative position to the ridge center/axis, overall moisture in and around the high pressure (not all high pressures are dry), mean wind direction, and how the surface pressure is set up/aligned and how strong it is, and time of year/location (land or ocean). And we do not live at 500 mb. And what you say above, a 600 dm ridge parked right over region is not ideal for max or record heat. Having its center located decent distance SW, S , or SE of a given location is best for an area like the East Coast. On 9/16/1989 at 00z, the Chatham MA (CHH) souring recorded a 609 dm height. That is record high for the Northeast, but there was no all-time record heat for Sep from that event on the East Coast. Aug 2, 1975 when New England has it hottest temp on record. The ridge center was to our W, and we had strong NW flow for subsidence warming. Highest 500 heights were our W. Many times when the ridge center is to the W, the downstream sfc high is strong and that promotes a cooler thickness column and onshore winds. In other words, it is not one-size-fits all, and using any one parameter or level to determine sensible wx at the sfc and how extreme it will be or not is not proper meteorology. For heat, one should be looking a lot more at the 1000-500 thickness, as that is much more correlated to temps at the sfc b/c it combines 500 heights w/ sfc pressure. Also, 850 temps, but even that has limits. Cloud cover? Precip? Lapse rates? Type of air mass? You can't treat individual parameters in a vacuum.

Good point. Yes, it does matter to an extent. But each site is different. The below sounds pedantic and getting into the weeds, but I have found an appreciation of the details working w/ numbers, calcuations, and statistics, their rules, and how it applies to the sciences. We know the history of BOS wx measuring issues -- temp, precip, and snowfall. So this is not an isolated or new issue. And then you have the base issue of ASOS temp considered ok as long as it is within +- 2 F. The point is marginal of error or uncertainty in measurement is rarely given in the mainstream. Output/results are often treated as absolute fact. This is not a good scientific practice. For example, If a number is known to be accurate to the ones place (whole number), expressing it with a decimal (like a tenth) introduces false precision. This implies you know the value more precisely than you actually do. So since ASOS is only reliable within +-2 F, see the problem here? And then you have individual site calibration issues at times independent of the sensor base accuracy. These wx sensors in the field are not high quality super precise like sensors used in a lab. And a larger issue not directly related to precision/accuracy, artificial heat sources are becoming more of an issue w/ time, both on a local and large scale where many of these climate locations are, so biased warm is not an unreasonable assumption a lot the time. Yes I know this complicates things, but if you are going to say that an avg temp over a long period of time is exceeded a previous record by tenths of a degree when you have issues like the above, we can't just ignore the limits of measurements and rules of what is precise/accurate. It gets worse when you see temps calculated out to the hundredths of a degree (global avg temp, as one example) That is two orders of magnitude above conventional sensor precision!

And this not far over the ME border in 1825? One of largest wildfires in NAMR history. https://en.wikipedia.org/wiki/1825_Miramichi_fire You go back far enough in recorded history, you see that massive events are not as unusual or atypical as they may seem.

Dang! That's quite a swirl, but largely at mid-levels. it looks like it is detaching itself from the main 500 low. We could see pinwheeling small LLCCs if the convection collapses completely.

A good part of the FL PH could use the rain!

I think thick smoke can go both ways. On Tue, big time svr wx (best SCP and SIGTOR parameters I have seen in a long time in the Northeast), was completely squashed during the daylight hours at least. Otherwise there would likely have been a sig tor event in srn Quebec and nrn New England. Temps were held down a lot. BOS fcst high as 97, and high was only 90. PWM fcst high was 93, and only got to 85. This resulted in CINH remaining stronger over the entire area. However, ydy we saw a nasty back-building tstm training event in cntrl NJ. Wind gusts as high as 84 mph at Surf City and they also had 4.37" of rain. CG LTG was incredibly dense in a narrow swath. And these storms fired directly within the thick plume of smoke. One can say w/ high confidence the smoke in the Northeast was the cause for the svr wx bust here, but for what happened in NJ ydy? Not as clear. That would be a good case study/research item, re-run models w/o the smoke, and see if intense tstms would have occurred to the degree they did! The models for tomorrow have smoke in their initialization, unlike what happened on Tue in the Northeast, so it is accounted for. I am not impressed w/ the 18z HRRR storm coverage tomorrow over the region. 18z RRFS is a little better, and shows an isolated honkin' supercell just N of DC, but the 45% area for wind seems high for the DMV area to me given the *coverage* of storms fcst. This is important. The colored SPC outlooks areas are for expected svr wx type coverage, they say nothing about how intense any individual svr wx may be (the hatched areas show that) So they should be solid svr storms, just the real question is coverage overall. The thick smoke may be a factor here, but how much in either direction? We go from weak anticyclonic flow aloft today to solid cyclonic flow tomorrow w/ a s/w coming thru. 500 heights come down as well. But the NAM shows 500 temps actually increase a bit in the aftn, up to -4 C (yuck!). The GFS tho shows slight cooling from -5 C tdy to -6 C tomorrow. Also, the mid-level lapse rates are not as bad as you would think for such warm 500 mb temps. Looking at the NAM and GFS, it shows lapse rates as high as 7 C/km on the fcst soundings (not using 700-500 exactly here, any thick layer at mid-levels will do). Fcst K-indices in the area gets as high as 40 on both the NAM and GFS, and that is impressive. Juiced column for big rains! NAM has PWATs are high as 2.8" which is likely overdone. GFS has it as high as 2.5" which is good for this model (not usually that high)! Anything over 2" is more than enough. Since DCAPE is fcst high and 0-3 km CAPE low, tor threat seems minimized. 0-6 km shear 35-40 kt, so enough for supercells.

Looking at the ECMWF fcst, it remains cold core aloft for the next several days (see 700 temp 48 hr fcst attached), and at 850 elongated N-S w/ a broad wind field (see 850 winds 60 hr fcst attached). Not much sfc low reflection. I think they may be a case that aloft it is and will stay impressive w/ lots of deep convection/decent swirl, but low-levels struggle to organize. We've seen this before and it looks great on satellite, and some ppl are going, "I can't believe NHC has not declared this yet!" But sfc observations and microwave data show a low-level center ill-defined and/or not tight.

Thick smoke was no inhibitor for the nasty training storms in cntrl NJ today. And look at that CG density even zoomed up! CoastalWx: "WHY CAN'T WE GET THAT HERE!?" visloop5.mp4

See how even a small temp bias can make all the difference when it comes to historical rankings? Looking at the past few months, BOS temp is running around 1 F too warm. So remove that bias, and BOS so far this summer is #5 warmest or higher. Non-trivial difference.

We have plenty of redundancy up there for GOES satellites. Heck, there are even satellites up there launched over 15 years ago that are still operational and in use GOES-15, launched in 2010, was the GOES-W satellite until 2018. Then this satellite ownership was transferred to the DoD, and redesignated EWS-G2, and now sites at 62E. So worse case if GOES-19 failed, we could move other satellites to take it place.

Reminds me of anvil shading. Thick, large, sharp anvils from intense storms can induced a thermal gradient on their edges well downwind. Another mesoscale wildcard the models will not handle well or at all!

The training on this storm was incredible. And it was smack dab in the middle of the thick smoke plume, so that did not seem to inhibit things, and maybe enhanced things (cloud condensation nuclei different?). Smoke as to impacting convection has some studies, and results vary. One was smoke plumes seem to increase the frequency of +CGs. I attached the CG plot zoomed up color coded every 20 min going back 2 hr ending 724pm EDT. The density is wild! Radar rainfall estimates show up to 6" in some locations. visloop5.mp4

The NAM is woefully outdated as a model. I do not think it has been updated to tweaked in 10 years or so. It is mainly for a "quick, early look" and I think that's why I has stuck around for so long! Generally, I do not use the NAM after 36 hr, as it does odd things. And the model was never designed for TCs, so never use it for them. The NAM and all its derivative models are going away in Oct (was going to be Aug but pushed back), The RRFS will replace it. The RRFS has its issues, but from what I have seen, it does much better than the NAM.

Yes, I figured that is what happened, and you confirmed it. I work w/ fire and smoke detection and mapping where I work. Here is our main product. https://www.ospo.noaa.gov/products/land/hms.html#maps Gets reset every day around 6am, and fire points and smoke areas are added in real time both automatically and manually during the day through late evening. Wind by *far* is the biggest factor in wildfire spread and intensity. And w/ the passage of a cold front you are going to get drier air advected in as well, so smoldering or low-level fires suddenly can get a massive boost. This also happened in central Quebec last summer or the summer before. Smoldering fires ignited by lightning and held at bay by rain occurred, and then the cold front passed, and all at once, you saw multiple fires erupt in sync across the region w/ big smoke plumes. This is was due to strong winds behind the cold front. Some think, "but it just raining a lot, how could things burn so much?" Well, that's a disconnect that exists. Things are a lot more complex than led on. There is a reason why fire wx has it own branch in meteorology, and the nuances and idiosyncrasies are rife and not what you'd expect! It is pretty amazing stuff. The sheer amount of training modules on MetEd/COMET is impressive, so that shows how big and complex this field is. And despite what MSM constantly pushes, drought or hot temps have little or nothing to do w/ wildfires. High winds are low RH are *everything*. You can have the wettest month on record, and then get fire wx warnings not days later. Recall March 2010 how wet it was in SNE, esp. RI? Well, a few days after a big flood event events, fire wx warnings were put up for the region This b/c windy conditions and low RH will dry out grass and shrubs in short order (called 1-hour fuels). Also, being spring, it's all still dead vegetation that burns easily. Open grasslands in the Plains are the same. Massive wildfires occur when no drought is present, again b/c it is largely 1-hour fuels. And in places like CA? Well, you have the wet season, and then the dry season by default, so most everything that sprouts/grows during the wet season, dies and decays in the dry season for a prime fuel load, and the wetter the wet season, often the worse that wildfire season later in the dry season. Couple that w/ Santa Ana winds, and drought conditions are irrelevant. You are going to get dried out and desiccated vegetation for lots of wildfire fuel no matter what every year.

Quite the tree damage I am told Springfield VT to Claremont NH. I-91 was closed for a time. Saw this report: "You can see the path just south of mile 48. I-91 is a debris field for a quarter mile. Twisted trees snapped off that were more than a foot in diameter."