The Mother 'Effin WEATHER Thread

[JMR]

Tornado Outbreak Likely Saturday Evening - Folks in the Great Plains states, particularly Kansas and Oklahoma, need to monitor weather conditions closely today through Saturday night. The Storm Prediction Center is forecasting a high risk of severe weather, including strong tornadoes, over Kansas and Oklahoma on Saturday evening into the overnight hours. The overall risk area includes Nebraska, much of Iowa, western Illinois, northwest Missouri, and northern Texas. Please monitor www.spc.noaa.gov and weather.gov for the latest information.

Stay safe tornado alley people.

[Alan Dunkin]

From yesterday (I'm still pissed I couldn't get a good spot last night):



Yes now a High Risk for central Kansas/Oklahoma.

A CORRIDOR OF
MODERATE TO STRONG INSTABILITY IS FORECAST ACROSS ECNTRL KS...CNTRL
OK INTO NW TX. THIS COMBINED WITH STEEP MID-LEVEL LAPSE RATES AND
STRONG LOW-LEVEL SHEAR WILL BE VERY FAVORABLE FOR SEVERE STORMS AND
A TORNADO OUTBREAK WILL BE LIKELY ACROSS THE SRN AND CNTRL PLAINS
FROM LATE SATURDAY AFTERNOON LASTING THROUGH THE EVENING AND INTO
THE OVERNIGHT PERIOD.

...

0-3 KM STORM RELATIVE HELICITIES ARE
FORECAST TO BE AROUND 400 M2/S2 WHICH IS IDEAL FOR STRONG TORNADOES
AND A TORNADO OUTBREAK APPEARS LIKELY. THE GREATEST THREAT FOR
SIGNIFICANT TORNADOES SHOULD EXIST SATURDAY EVENING FROM SALINA SWD
TO OKLAHOMA CITY. 700 TO 500 MB LAPSE RATES AROUND 7.5 C/KM WILL
ALSO BE FAVORABLE FOR LARGE HAIL AND HAIL GREATER THAN 2 INCHES WILL
BE POSSIBLE THE MORE INTENSE SUPERCELLS.

There will be numerous sources to watch online, and the OKC TV stations will be primed and ready.

--- Alan

[Alan Dunkin]

Eastern Nebraska (including Omaha) and western Iowa area just got upgraded to High Risk tomorrow:

CELLS WOULD LIKELY FORM OVER WRN SECTIONS OF THE
HIGH RISK AREA WHERE HEATING WILL STEEPEN LOW LEVEL LAPSE
RATES...THEN WOULD PROCEED RAPIDLY NEWD WITH AN INCREASING TORNADO
THREAT. VERY LARGE HAIL WILL ALSO BE LIKELY. THE NRN EXTENT OF THE
TORNADO THREAT WILL DEPEND ON THE ACTUAL LOCATION OF THE PRIMARY
BOUNDARIES.

--- Alan

[Brian Rubin]

It's, like, seriously RAINING and thundering here in LA, which is a rarity. Of course the driving is in chaos.

[charmtrap]

From yesterday (I'm still pissed I couldn't get a good spot last night):

They're calling for more T-storms today and tonight.

Wow. Is this time-lapse, or did the bridge really get 8 strikes all at once?

[Alan Dunkin]

It's a 20-second exposure. However, given the nature of these things, more than likely the strikes were pretty close to one another, if not within the span of a second or so.

For California: yeah strengthening storms through the Central Valley today:

FARTHER N INTO THE CENTRAL VALLEY...COLD AIR ALOFT/STEEP LAPSE RATES
NEARER TO THE CENTER OF THE UPPER SYSTEM SHOULD -- WITH LIMITED
BOUNDARY-LAYER HEATING -- SUPPORT INCREASING AFTERNOON SHOWERS AND
ISOLATED THUNDERSTORMS. GIVEN THE STEEP LAPSE RATES/COLD MID
LEVELS...MARGINAL HAIL WILL BE POSSIBLE WITH A STRONGER CELL OR TWO.

--- Alan

[Pogo]

I could clone tool the hell out of that photograph if you uploaded the full resolution of it.

[Alan Dunkin]

Man, if you're gonna do a live streaming cam setup from within your vehicle and you're a part of a major operation (oh like TVN's new deal since Storm Chasers was cancelled), learn how to turn off auto-focus or just set focus to infinity by default. Otherwise the camera will either cycle through all focus states or just decide to focus on the interior of the windshield. In other words, you can't see a damn thing most of the time. Idiots.

--- Alan

[yamo yamo]

Now I know why the Great Plains were not called the Great Forests.

[Alan Dunkin]

Well, really started to fire up between Kansas and Nebraska so far...

BTW, there was a small-scale tornado up in this area yesterday (near Yuba City), and another one confirmed further south in the central valley back on Tuesday.

--- Alan

[Alan Dunkin]

By the way, there is an area of moderate risk for severe weather tomorrow for most of Wisconsin where this current system will translate to overnight.

--- Alan

[Alan Dunkin]

From last Saturday's outbreak:



Already seen some complaints that the chasers were out there clogging the roads on Saturday, which is not surprising:



High Risk forecasts bring out everyone, and in addition it was on a Saturday when everyone usually has time off. Restricted paved road networks funnel everyone into an area, and since the obvious place was in Kansas, that's where everyone was, and few chasers stayed in Oklahoma to see the dusk tornadoes (like the twins that moved into Kansas and eventually hit Wichita).

--- Alan

[Alan Dunkin]

Moderate risk for severe weather in eastern Kansas today:

MODEL SOLUTIONS ARE IN GOOD AGREEMENT THAT DISCRETE
CONVECTION WILL FORM ALONG THE DRYLINE OVER SOUTH CENTRAL KS BY LATE
AFTERNOON. THIS ACTIVITY WILL FORM IN A REGION OF STRONG
INSTABILITY AND FAVORABLE VERTICAL SHEAR FOR DISCRETE SUPERCELLS
CAPABLE OF VERY LARGE HAIL AND TORNADOES. THE WARM SECTOR WILL BE
RATHER NARROW...BUT WILL BE SHIFTING SLOWLY EASTWARD THROUGH THE
EVENING. IT CURRENTLY APPEARS THE MOST INTENSE STORMS WILL TRACK AS
FAR EAST AS WESTERN MO BEFORE A SLOW WEAKENING PROCESS THIS EVENING.

--- Alan

[Alan Dunkin]

This year's storm chase trip is getting set. Timing hasn't been great with a lot of crap going on, but finally will be in a spot to actually go, and have at least a bit of financial freedom to do what I want (although maybe not nearly enough time, as a friend is coming into town for a few days and I'm already taking time off for that, but I'll have to live with it).

So in about 3 weeks I'll be flying out to Denver. I'm sorta anchored on one night as earlier this year I got a room in Vail on a deal and don't really want to waste the money (and I have to use it before the 14th), so I fly in early and Vail will be the first night (~2 hour drive from Denver).

The general notion is that severe weather chances traditionally migrate north after May from the southern/central plains to the central/northern plains. Western Kansas, the Nebraska panhandle, southeastern Wyoming and eastern Colorado are all within 4 hours of Denver, give or take, and since I'm not locked down after the first day, I can spend days out there at a time, which will be helpful if I have to go into the Dakotas or further east.

If the weather doesn't want to cooperate, well, there's still a lot of crap to do out there anyway. If it looks totally dead, I can spend a lot of time in Wyoming and hit the Tetons and Yellowstone. Partially dead, I can hang in Colorado or maybe hit the Badlands. But there's options across the board, so I think I can stay fairly satisfied no matter what. It'll only be a week or so, but the possibilities are fairly open, and I think I can probably extend a day or two if necessary.

No long distance drive this time as I'll be flying. Makes me worry about having a rental but that's a liability I'll have to live with.

--- Alan

[RepoMan]

Good luck sir! Post every conceivable cool picture to this thread plzkthxbai.

[Alan Dunkin]

FYI decent chance of severe weather throughout Wisconsin Thursday...

--- Alan

[Alan Dunkin]

Now moderate risk sitting over most of the state:

BY EARLY TO MID AFTN...LARGE SCALE ASCENT WILL INCREASE OVER IA/SE
MN AND WRN WI WITH THE APPROACH/AMPLIFICATION OF UPSTREAM VORT MAX
NOW OVER WRN NEB. COUPLED WITH SFC HEATING AND MODEST LOW LVL
MOISTURE RETURN...THIS SHOULD FOSTER NEW STORM DEVELOPMENT ALONG THE
ERN FRINGE OF THE CONVECTIVE BAND...AND/OR STRENGTHENING OF EXISTING
STORMS FROM NRN/ERN IA NNE INTO SE MN AND WRN WI.

...

LIKELY CONTINUED PRESENCE OF SOMEWHAT DRIER AIR TO ITS
EAST...AND WARM SECTOR EML CAP ALL SUGGEST THAT STORMS SHOULD EVOLVE
INTO A SSW-NNE SQLN...WITH STRENGTH OF SHEAR SUPPORTING NUMEROUS
EMBEDDED LEWPS. ASSOCIATED ROTATING STORMS...SUPERCELLS...AND SMALL
BOWS WILL BE CAPABLE OF SWATHS OF DMGG WIND AND TORNADOES.

--- Alan

[Omniscia]

The weather radio just went off here, chirping about some tornado watch or another. Unfortunately, the phone also rang at that same exact moment, so I didn't catch the details of the alert.

Of course, NOAA hasn't updated their website yet, but as of 10:35, here's what they were calling for:

ADDITIONAL SEVERE THUNDERSTORMS WILL REDEVELOP ACROSS THE NORTH
COUNTRY BY EARLY THIS AFTERNOON. THESE THUNDERSTORMS WILL BE
CAPABLE OF PRODUCING HAIL UP TO 2 INCHES IN DIAMETER AND DAMAGING
THUNDERSTORM WIND GUSTS TO 60 MPH OR MORE. FURTHERMORE...THE
POTENTIAL FOR A BRIEF TORNADO SPIN UP WILL BE
POSSIBLE...ESPECIALLY DURING THE MID AFTERNOON HOURS ACROSS
CENTRAL AND NORTHERN VERMONT.

Fun!

Oh, there we go:

TORNADO WATCH 313 IS IN EFFECT UNTIL 900 PM EDT...

[Alan Dunkin]

Wow yeah, that's a bit unexpected, a Moderate Risk area was updated this morning for most of upstate New York.

DEW POINTS IN
THE 60S TO LOWER 70S F COUPLED WITH MIDLEVEL LAPSE RATES AROUND 7
C/KM WILL CONTRIBUTE TO A MODERATELY-STRONGLY UNSTABLE AIR MASS WITH
MLCAPE VALUES INCREASING TO 2000-3000 J/KG. THIS DESTABILIZATION
ALONG WITH THE EWD PROGRESSION OF THE UPPER TROUGH WILL SUPPORT A
MARKED INCREASE IN STORM VIGOR AND COVERAGE BY EARLY AFTERNOON ALONG
THE COLD FRONT AND/OR LEADING EDGE OF THE COLD POOL ASSOCIATED WITH
THE ONGOING STORMS. ADDITIONAL DEVELOPMENT IS POSSIBLE ALONG A
REMNANT OUTFLOW BOUNDARY ACROSS THE MOHAWK VALLEY...AND A
PRE-FRONTAL TROUGH OVER ERN NY/PA.

ALTHOUGH THE STRONGEST MID- AND HIGH-LEVEL WIND FIELD ASSOCIATED
WITH THE TROUGH IS FORECAST TO LAG THE WARM SECTOR TO THE W...LOW
LEVEL WINDS WILL STRENGTHEN SOME ACROSS ERN NY AND WRN NEW ENGLAND.
SHEAR PROFILES WILL BE SUFFICIENT FOR DMGG WINDS AND POTENTIALLY
SUPERCELLS...ESPECIALLY INVOF THE HUDSON VALLEY. A TORNADO THREAT
WILL ALSO EXIST ALONG THE WARM FRONT OVER PORTIONS OF NEW ENGLAND
WHERE LOW-LEVEL SHEAR WILL BE ENHANCED.

Also a moderate risk area for Oklahoma tomorrow, though in both of these cases it appears that tornadoes are really not the predominant risk, but extremely high wind and large hail.

--- Alan

[Omniscia]

Aww, hail, no.

[Alan Dunkin]

Omni, the WW is at:

http://www.spc.noaa.gov/products/watch/ww0313.html

--- Alan

[Omniscia]

Sweet. So, like, the whole darn state.

I can't recall any actual tornadoes in this part of the state, at least in recent memory, but we have had increasing trouble with wind shears over the past few years. One of the neighborhoods a few miles from here lost a bunch of trees to a microburst a while back.

[Alan Dunkin]

Some tornado warnings up in the Vermont now.

--- Alan

[Cougar]

Tornado's in Vermont? That sounds very out of place to me... is that perception deserved? I have no idea.

~C~

[Alan Dunkin]

Eh, tornadoes are possible (and have happened) in every state of the union.

Tomorrow should be an active day in Oklahoma with a Moderate Risk setup forecast two days ahead of time:

WITH VERY STEEP MID-LEVEL LAPSE RATES BEING CONTINUALLY SUPPLIED BY
WLY FLOW ALOFT -- SPREADING ATOP A MOIST/HEATING BOUNDARY
LAYER...STRONG DESTABILIZATION WILL OCCUR...WITH AFTERNOON CAPE
VALUES OVER WRN OK AND VICINITY FORECAST TO EXCEED 4000 J/KG
MIXED-LAYER CAPE. THIS THERMODYNAMIC ENVIRONMENT WILL ALLOW
EXPLOSIVE CONVECTIVE GROWTH ONCE STORMS INITIATE...FURTHER AIDED BY
DEEP-LAYER SHEAR SUPPORTIVE OF UPDRAFT ROTATION. ISOLATED STORMS
DEVELOPING ACROSS WRN OK AND VICINITY WILL LIKELY PRODUCE VERY
LARGE/DAMAGING HAIL...AND WILL ALSO BE CAPABLE OF PRODUCING DAMAGING
WINDS. WHILE SOMEWHAT WEAK LOW-LEVEL FLOW MAY LIMIT TORNADO
POTENTIAL IN MOST AREAS...ENHANCED SHEAR NEAR/N OF THE SURFACE
FRONT/REMNANT OUTFLOW MAY SUPPORT A ZONE OF SLIGHTLY HIGHER TORNADO
PROBABILITY.

A CAPE of 4000 J/KG is kinda nuts and represents a huge well of extremely unstable air.

--- Alan

[Alan Dunkin]

Head's up in the northeast, there's a moderate risk of severe weather in the Maryland/Virginia/DC area today:

A TORNADO THREAT WILL LIKELY
DEVELOP AS THE STORMS INTERACT WITH A WARM FRONT WHICH IS FORECAST
TO BE FROM SCNTRL PA EXTENDING SSEWD ACROSS NRN VA AND MD AS THE
LINE APPROACHES FROM THE WEST. THE TORNADO THREAT SHOULD INCREASE
ACROSS PA AND MD AS THE STRONGEST BAND OF LARGE-SCALE ASCENT
APPROACHES LATER THIS AFTERNOON. A COUPLING OF THE LOW AND MID-LEVEL
JETS IS ALSO FORECAST TO OCCUR ACROSS NRN VA...MD AND PA WHICH MAY
ALSO HELP TO ENHANCE THE QLCS TORNADO THREAT. HAVE ADDED A MODERATE
RISK IN THE WASHINGTON DC METRO...BALTIMORE AREAS WHERE THE TORNADO
THREAT IS EXPECTED TO BE THE GREATEST AND WHERE AN ISOLATED STRONG
TORNADO CAN NOT BE RULED OUT. ANY ROTATING STORMS SHOULD ALSO BE
CAPABLE OF PRODUCING WIND DAMAGE. AS THE STRONGER LARGE-SCALE ASCENT
MOVES ACROSS THE MID-ATLANTIC EARLY THIS EVENING...A WELL-ORGANIZED
LINEAR MCS IS EXPECTED TO BECOME THE DOMINANT CONVECTIVE FEATURE
WITH AN ENHANCED WIND DAMAGE THREAT PRESENT ACROSS A LARGE AREA OF
THE MID-ATLANTIC.

--- Alan

[WarrenM]

Aww, hail, no.

I laughed way too hard at that. Awesome...

[Alan Dunkin]

There are already Tornado Warnings on cells west of DC near Leesburg.

--- Alan

[Alan Dunkin]

Been some very nasty turning supercells in the DC region but no reports of confirmed tornadoes on the ground, though there has been one definitive one in Pennsylvania. Still nasty weather, our office lost power in Baltimore. And the potential is still definitely there.

--- Alan

[Alan Dunkin]

Okay, reports now of a tornado inside the perimeter at BWI Airport in Maryland as well as around Hampton, VA.

--- Alan

Edit: Hampton tornado video - http://www.youtube.com/watch?v=oQkkAPnKEao