Chase Case #5 (2010 Version)

[Jesse Risley]

Are we ready for another installment of SDS-related virtual chases?

SPC Synopsis (06z outlook)

THERE IS A MDT RISK OF SVR TSTMS THIS AFTERNOON AND TONIGHT.....SUPERCELLS WITH LARGE HAIL AND POSSIBLY TORNADOES WILL DEVELOP.......

PERSISTENT UPPER LOW OVER THE LOWER LAKES IS FORECAST TO MOVE EASTWARD INTO NY DURING THE PERIOD. WNW[FONT=&quot]
[/FONT]FLOW WILL CONTINUE OVER THE CENTRAL AND SOUTHERN PLAINS...WITH[FONT=&quot]
[/FONT]ASSOCIATED THERMAL/LEE LOW OVER WEST TX. ERSTWHILE...SEVERAL TROUGHS ARE FORECAST TO PHASE ALONG THE WEST AS THEY MOVE ONSHOREBY SUN EVENING.

00z (evening before) Data

250 mb
300 mb
500 mb
700 mb
850 mb
925 mb

radar (CONUS)
surface (CONUS)
wind profiler agl wp
wind profiler msl wp
vis satellite (CONUS)

 

[Chad Moore]

"Erstwhile"? You don't see that word too often. : )

This chase case is going to take me into unfamiliar territory.

 

[Damon Scott Hynes]

OKC, what the heck? I'll probably be heading westish later on, but I'll head to the nearest Love's and look for the lightbars!

 

[Adam Lucio]

OOOoooo tough one here.

Put me in Sayre, OK to start.

 

[Robert Dewey]

Ardmore, OK - this definitely looks like a dryline play. I like the strong + veered mid-level winds too.

 

[Skip Talbot]

Yeah that 0z pattern is kind of ugly. I don't see anything favorable coming out of that stacked low over the Great Lakes, and the troughs arriving from the West look pretty mediocre. Good moisture way down south and some day before the day type activity in west Texas. I'm guessing this area might be a favorable area the next day, and it looks like more western play given that the rather mediocre upper level energy is just coming on shore now. Put me in Childress, TX for the start.

 

[Jeff Duda]

I'll start in Guthrie, OK. Hoping for some moisture return north from some sort of LLJ overnight. Strange synoptic setup.

 

[Bob Hartig]

These chases lately are really stretching me, and that's good! In this case there's no obvious source of lift coming in from the west. I see a weak trough way off in the Pacific Northwest, and perhaps it'll dig a bit in response to the upper-level speed max that's blowing in off southern California. That latter feature should arrive tomorrow along with a more westerly flow as the present ridge translates eastward.

Other than that, moisture doesn't seem to be an issue. Woodward, OK, for me, and catch a good night's sleep.

 

[Dean Baron]

I'll take Shamrock, TX for the night. Looks like a front/boundary is sitting out towards the TX/NM border so hopefully this puts me in good position for tomorrow.

 

[Bob Hartig]

Just took a second look. 850 map by DDC shows a temp of 19C; 700 = 5C. If that bears out, then lapse rates should be impressive. Just a stone's throw to the south, though, it's super capped off. Interesting to see the temperature contrast so clearly defined at the 700mb level. Something to note and see how it plays out tomorrow.

 

[Robert Dewey]

Just took a second look. 850 map by DDC shows a temp of 19C; 700 = 5C. If that bears out, then lapse rates should be impressive. Just a stone's throw to the south, though, it's super capped off. Interesting to see the temperature contrast so clearly defined at the 700mb level. Something to note and see how it plays out tomorrow.

I was thinking the same thing RE the cap, but those storms in NW TX look quite robust.

 

[Andrea Griffa]

Today I'm starting off from Ok City, it's still too early to make any target.

 

[Chad Moore]

Don't see any tornadic potential in New England or Florida, but TX/OK has the moisture and the helicity to make it work. There is some upper level divergence to encourage convection- possible that this divergence translates eastward into richer moisture. So I'm starting in Seymour, TX.

 

[Bob Hartig]

I was thinking the same thing RE the cap, but those storms in NW TX look quite robust.

True, dat. But cross-check their location with the H7 map and you'll see that they're firing on the edge and east of the capping inversion.

 

[cstrunk]

I'm leaving Fort Worth right now and will overnight in Wichita Falls, TX. This is a tough one to forecast with very little data, and a different set up. I'm hoping those storms in NW TX tonight lay a nice outflow boundary in the area. I guess we'll see how things look in the morning.