Chinook

Even Cats Make Weather Forecasts

The NAM always seems to overforecast freezing rain. The 00z NAM has 0.75" to 1.18" of freezing rain accumulation near and north of Springfield MO, as well as some other various values of freezing rain from New Mexico to the Mid-Atlantic. Note: NWS gridded forecast has 0.03"- 0.08" freezing rain north of Springfield. I hope you guys don't have nasty tree damage or anything like that. Maybe the models like to keep the inversion layer there for a longer time period than is really possible.

-45 to -53F near Edmonton, Alberta

I found this annual lightning map tweeted by @brendonme. I wonder if this could be originally from NOAA

Interesting stat: Toledo OH gets exactly 5.2" (Kuchera ratios) with the 00z GFS and 00z Canadian. With this storm, the borderline of rain/snow is going to be hard to forecast, and may come down to nowcasting, so this consistency means almost nothing at this point.

This is a really low heat index (72 hour forecast). I think the heat index formula may be broken.

Interesting weather feature: along with this storm, yesterday there was a 232 kt wind at 250mb in Canada.

Nothing is really happening here, as the cold air won't lock in. Thursday, my area had a high of 59, which is the highest since the big snow in November. In the models, the consensus is that the developing 500mb storm system on Thursday-Friday is pretty good, but downsloping wind will prevail as it passes by here and creates a huge storm in the Midwest. My area still has some snow in the shade left over from November 25th-26th, like a huge mass of icy stuff next to the driveway. The Pacific Northwest snowpack is building, and low elevation areas are getting rainfall to diminish drought conditions. By my estimate, the high Cascades have gotten 8 ft - 15ft of snow since January 1st.

By the way, yesterday had more tornado watches than tornadoes.

That's pretty funny. By the way, it looks like Huntsville AL radar is not working, but there's a possible tornado southeast of Huntsville. Edit: HTX has radar data now.

There are two possible tornadoes north of Birmingham AL. This is definitely a James Spann moment if there ever was one.

possible tornado near Tuscaloosa

Radar-confirmed tornado at Carrollton/Reform Alabama (probably what's in the last post?)

Stronger rotation may have developed in the past few minutes near Jasper, Arkansas. The storm is getting farther away from KLZK and KSRX radars, though.

Maybe the severe weather will ramp up soon in far northeast Texas into southwest Arkansas, including the current tornado warning at Woodland TX/ Red River area. Otherwise... 30 severe reports so far would be a very low # of severe reports if things don't get active.

New tornado warning south of Fort Worth, heading for FWS radar.

Maybe this is one of those "oops" moments for automated sensors - Chariton, Iowa has had RA and +RA with temps below freezing KCNC 102235Z AUTO 36021G29KT 1 1/4SM +RA FEW007 BKN013 M02/M02 A3003 RMK AO2

Why? Is this super confusing or something? The GFS and NAM-3km have some ice in these areas.

New tornado warning says that this is a radar confirmed tornado. (Zeb, Oklahoma)

Winter Storm Watches have been issued for Wichita, Chicago, Michigan, Iowa, Wisconsin. It seems that several overlapping weather watches/warnings/advisories can make the NWS web pages confusing

This is the NWS forecast for the next 66 hours. I'm sure they will be basing their winter storm watches and winter storm warnings on this or something similar. The Weatherbell web site also has a graphic for the freezing rain expected, but it's confusing right now, but it says 0.48" of freezing rain for Grand Rapids, MI.

Regarding Saturday, the 12z NAM has SigTor values of 3-5 in southern Mississippi at 12z. Unlike many days in the summer, severe weather should be happening around 12z.

As an interesting side note, you can use the PivotalWeather ECMWF clickable soundings to check for severe weather parameters.

We need to have something more specific than simply a negative PNA index number. We need to have a trough that develops near the West Coast and tracks toward here UT and CO (Four Corners), with perhaps even a ridge just off the West Coast. The PNA index doesn't capture that well, but the index could be negative when that happens. On the other hand, we could get a lot of cold air on the Plains and have upslope event with more arctic air and less of an organized 500mb trough. The PNA or NAO indices may not capture that well. In rare circumstances (like an El Nino,) we could use a large California 500mb low to track toward us, via the Four Corners.

NWS Boulder lists top weather events of Colorado within the last 10 years