Chinook

Dear Mexico Plz measure weather during a hurricane. Thx.

I was going to try to discuss the upcoming pattern change, but I have some problems. The GFS ensembles and ECMWF ensembles don't even really agree as to the overall pattern at 6-7 days. ECMWF does not drop the freezing air into northern Colorado on Oct 26.

Hey Mayja, remember this 2021 dual-metro snowstorm? It somehow failed to drop heavier snows over the Palmer Divide but successfully dropped over 6" at Colorado Springs.

red maple or sugar maple?

completely re-vamped web site for Aviationweather dot gov shows an integrated METARS, NWS warnings (not sure about convective warnings yet), radar, and aviation stuff that's kind of not that useful to us. You can turn on/off the radar, aviation stuff. Here is a sample of what it's like to look up previous observations from more than two hours ago. You have to go to archive mode, but it's pretty easy.

I was messing around with the radar archive to find out about the Manchester SD tornado. Instead of the Manchester tornado, I made this plot of a different tornado, connected to a massive supercell. It was closer to the FSD radar, June 24, 2003. Tornado Archive says 95 tornadoes in 1 day.

My new loop of the past 15 days, 250mb jet stream analysis https://great-lakes-salsite.web.app/Oct_1_15_2023_250mb_loop.html

It's fine. You can't control the weather by starting a thread on a computer forum. El Nino is coming up. At some point in time you'll start looking for those California 500mb lows that become a snowstorm in Denver.

It's the CoCoRAHS web site, the map on top of the page is the interactive map. Then, you have to push the button for "RANGE" and then you have to choose two calendar days. You might want to zoom in to a local area before doing the multi-day calculation. (note sure if that's important.)

north Illinois 3-day precip

Hey look I found a mid-latitude cyclone

I found some weather for ya. Now there is a winter weather advisory for over 9000ft, with various winter weather products issued for over 7000ft in Wyoming. All of which might be translated to "huge winter storm" if it impacted any type of Midwest area.

140kt-160kt jet stream bashing into the West Coast, and there's a blocking pattern in the way. This leads to chaos. And by that I mean the the surface low will eventually cut under the block and go the Mid-Atlantic. But apparently the severe weather risk tomorrow is kind of a small slight risk.

Wow, I didn't even realize Hurricane Lidia had recon until now. 951mb and over 96 knot winds displayed here!

With reference to my previous post, the Manchester SD massive F4 tornado (June 24, 2003) must have had some reason why the STP would have been considerably greater than 1. (say, for example, locally lower LCL and higher 0-1km SRH.) Compare the huge CAPE, huge SCP and low STP here.

Today, back to 80 at Greeley and 80 at Denver, even 78 down by KAPA airport. This is quite typical as the strong upper level trough pulled away from the Plains and is sitting in the Great Lakes/Ontario. The 500mb height and surface temperatures always get much higher in response to the upper low moving east. An official high of 80 at KDEN is 12 degrees above the normal high. There's just a huge amount of above-normal temperatures along the Rocky Mountains going from Mexico all the way up to the Northwest Territories.

Now this Aviationweather dot gov web site is changing, allowing a more complicated interface for the METARs. I kind of liked the ease of use.

The NCAR/UCAR web site has had the same useful surface-observations interface for, I believe, over 20 years. The models part of the web site hasn't changed either. Of course, weather enthusiasts have moved on to much better model web sites. It's one of those things that's kind of a constant in the universe. The CoD weather web site has existed for over 20 years, but of course, they pretty much upgraded everything. They have kept some of the color-bars used for model maps. So that's kind of neat. Not a whole lot stays the same on the internet. Another thing that's stayed the same a long time: NCEP/NCAR reanalysis on NOAA-PSD, exact same color-bars and interface for selecting plot parameters.

I've been kind of messing around with Tornadoarchive dot com recently, clicking the "random tornado day" feature. Along the way, I rediscovered some interesting days July 1-3, 1997: a total of 52 tornadoes hit the upper Midwest and into the Northeast, including one in Canada near Detroit. Apparently this was the largest continuous outbreak of tornadoes in the month of July. There was an F2 tornado in the city of Detroit. Not directly associated with a tornado, 5 deaths due to straight line wind at Grosse Pointe Shores MI. Two F3 tornadoes were in Michigan, one was in Minnesota, and one was in Ohio. June 24, 2003: a total of 67 tornadoes occurred in one day in the "Great South Dakota Tornado Outbreak." Also, a total of 125 tornadoes occurred within a 3-day time span (June 21-24). A single F4 tornado occurred on June 24 and hit the small town of Manchester SD. The residents never rebuilt the city. There were a large number of F0 tornadoes in South Dakota in a couple of counties. November 22-24 2004: Wikipedia says this was the largest number of tornadoes (104) in one continuous outbreak in the month of November. The worst ones were just three F3 tornadoes in Louisiana and Mississippi. 61 tornadoes were rated F0

Rain totals shown here are over 3.0" for western Michigan near Kalamazoo. My place got about 0.70" and then 0.05". You can already see the enhanced precipitation in the central Upper Peninsula from the instability.

Toledo was 87 degrees on Wednesday Oct 4th, , now it's 55, so a 32 degree drop in 3 days.

The Dallas Fort Worth area got some hail/wind reports. I'm sure you guys will be happy to see some of the drought-busting rains and some cooler weather, like 71 for Saturday. I guess in the long run, the drought might go away for the South but remain in the North due to El Nino.

For me, it's not usual to check the connection with this USA cold front and associated 500mb trough, and the 250mb wind stream. The 500mb chart does not easily show this. The subtropical connection to our sort-of merging jet stream goes all the way from the mid-Pacific near Hawaii up and then up to the Great Lakes. That's why I decided to save the 250mb North America charts of last month, post the loop and perhaps keep up with the whole thing. The El Nino's effects on the atmosphere are going to pop up in force, and the subtropical jet is the major player for North America. That's the thing. I don't know what conclusions I will get from looking at the jet streams way out in the Pacific every day.

The northeast side of Dallas may have gotten 2.5"-3" at this point in time. I have not seen a report of a tornado.

wow, it's 11:00PM in October