DAILY CHASE ACCOUNT 090504

[Guest ChaserUK]

Righty then people. Have decided on my initial target area as Albert Lea in SC Minnesota. There is a very good road network and I epect things to blow up in that region. Skies are clear so plenty of time for daytime heating to make the atmosphere unstable enough.

[Guest ChaserUK]

Quick update have parked outside a Holiday Inn on I90 whilst heading E towards target area - have perfect Wi-Fi access!!! Anyway, the area is now under MODERATE risk of severe weather - including tornadoes Anyway, will hang around here for a bit and see what happens.

[Guest ChaserUK]

WOW - NWS have just issued a Severe Thunderstorm Watch for this area - this means they should start firing within the next three hours or so.

[Paul]

Cool mate, your getting quite good at this chasing thing aren't you!!! Look forward to hearing your reports as things get going

[Paul]

As Chaser says, he is currently in a moderate risk area for severe storms. The following watch has just been issued for his area:

THE NWS STORM PREDICTION CENTER HAS ISSUED A

  SEVERE THUNDERSTORM WATCH FOR PORTIONS OF  

   

         CENTRAL AND SOUTHWEST MINNESOTA

         EASTERN SOUTH DAKOTA

   

  EFFECTIVE THIS SUNDAY AFTERNOON AND EVENING FROM 230 PM UNTIL 800

  PM CDT.

   

  HAIL TO 2.5 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 80

  MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

   

  THE SEVERE THUNDERSTORM WATCH AREA IS ALONG AND 65 STATUTE MILES

  EAST AND WEST OF A LINE FROM 60 MILES SOUTHWEST OF SIOUX FALLS

  SOUTH DAKOTA TO 55 MILES NORTH NORTHEAST OF SAINT CLOUD MINNESOTA.

   

  REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE

  FAVORABLE FOR SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH AREA.

  PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR THREATENING

  WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS AND POSSIBLE

  WARNINGS. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY DO PRODUCE

  TORNADOES.

   

  OTHER WATCH INFORMATION...CONTINUE...WW 170...

   

  DISCUSSION...COLD FRONT MOVING SEWD ACROSS ERN SD WITH AIR MASS IN

  ADVANCE BECOMING STRONGLY UNSTABLE AND WEAKLY CAPPED.  WITH 40-50 KT

  OF DEEP LAYER COUPLED WITH THE INSTABILITY AND STEEP LAPSE

  RATES...THUNDERSTORMS WILL RAPIDLY DEVELOP ALONG AND AHEAD OF FRONT.

   POTENTIAL EXISTS FOR SUPERCELLS ENHANCING LARGE HAIL AND WIND

  THREAT.

   

  AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT

  TO 2.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 70

  KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 550. MEAN STORM

  MOTION VECTOR 26035.

Don't forget you can stay upto date with all the latest warnings etc from the US on this page: http://www.net-weather.co.uk/usachase2004/...chase2004.shtml

[Paul]

Tornado watch issued :shock:

THE NWS STORM PREDICTION CENTER HAS ISSUED A

  TORNADO WATCH FOR PORTIONS OF  

   

         SOUTHERN MINNESOTA

         WESTERN WISCONSIN

   

  EFFECTIVE THIS SUNDAY AFTERNOON AND EVENING FROM 355 PM UNTIL 900

  PM CDT.

   

  TORNADOES...HAIL TO 3 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS

  TO 80 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

   

  THE TORNADO WATCH AREA IS ALONG AND 85 STATUTE MILES EAST AND WEST

  OF A LINE FROM 40 MILES NORTH OF MINNEAPOLIS MINNESOTA TO 50 MILES

  SOUTHWEST OF ROCHESTER MINNESOTA.

   

  REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR

  TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH AREA.

  PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR THREATENING

  WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS AND POSSIBLE

  WARNINGS.

   

  OTHER WATCH INFORMATION...CONTINUE...WW 170...WW 171...WW 172...

   

  DISCUSSION...STRONG SUPERCELL OVER WCENTRAL MN WILL CONTINUE

  DEVELOPING E/SE INTO A FAVORABLE SHEAR AND INSTABILITY ENVIRONMENT.  

  IN ADDITION TO POSSIBLE TORNADOES...VERY DAMAGING  WINDS ARE ALSO

  LIKELY.

   

  AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL

  SURFACE AND ALOFT TO 3 INCHES. EXTREME TURBULENCE AND SURFACE WIND

  GUSTS TO 70 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 550.

  MEAN STORM MOTION VECTOR 29035.

[Guest ChaserUK]

OK here is today's account. Unedited so forgive any spelling mistakes - I was typing it as I was heading towards a tornadic supercell!!!!! Anyway, did NOT see the tornado it must have roped out before I could see it. Also too much dark and rain - photo's to follow...

12:45

Heading N on the I29 from Sioux City. Initial target area is Albert Lea, SC MN. Here will be at a crossroads of N/S/E/W interstates. DP when we left Sioux City was 59F and it has already jumped to 62F. This would seem to tie with some of the models this morning showing a nice tongue of 65+ DP’s heading into the same area. Temps currently at 85F and skies mostly clear apart from a small bit of cirrus and an area of altocumulus to our SW. SPC convective forecast had us down for a SLIGHT risk area but NWS radio stating MODERATE risk. There is also a better chance of a tornado at the triple point today.

13:11

Still heading N on I29 towards Sioux Falls. DP has jumped to 63F now – a real indicator that moisture is on the return, more than likely the result of this 20mph (or higher) SW wind. SPC have gone for a 3pm initiation time – will have to see about that one but temps are already approaching 90F.

14:06

Now heading E of Sioux Falls only I229. Intend to get onto the I90 towards Albert Lea but may stop just short of there. The SPC has issued a MODERATE risk along and E of I29 which means we are already under the MDT risk area. Temps 88F and DP 60F.

15:25

Just crossed the state line into Minnesota on the I90 towards Albert Lea. We can see the anvil of a large supercell to our N – this storm and others will form in the vicinity of a warm front. However, additional storms are expected ahead and along a cold front heading into this area from the NW. DP a bit low at 59F but temps way up there at 93F.

16:54

After getting as far as Jackson on the I90 we had a call from Dave in Okarche. He said we should really head back west the way we came as the cold front could be getting ready to fire. Now heading back West on the I90. We will stop outside a motel which offers wi-fi and get some data. We can see excellent convection to our North which looks mighty tempting but this has been ongoing for a few hours – we want to be there when new storms eventually fire.

17:54

Towers going up to our SW, NW and NE at the moment as we head back on the I90 to the hotel where I could access the internet – I need data and FAST…..

17:48

Forget the data – we have found a cell we will target. It appears to be over near Rock Rapids. Just received a call from Dave who told us the same cell has the best potential at the moment so we are heading S as fast as we can. Massive faulted updrafts are visible – this thing looks nasty I have to say.

18:34

Still heading S on the I75 – the storm appears to be in Sioux County to our SW. We are going to position ourselves to see the rain free updraft area which seems to be coming into view as we speak.

18:45

Still on the storm – just received a call from Dave to say that the storm is not moving much – which I guess is a good thing – it appears to be getting its act together. Now it also looks like we have another storm chaser in a white vehicle in front of us.

18:57

NWS have just issued a Severe Thunderstorm Warning for the storm we are on. We are currently looking W and the main updraft area would still seem to be obscured. The warning did state the storm would remain in Union County – this thing is probably really organising. Still heading S on H75 towards La Mars.

19:14

Now in La Mars in Plymouth County, Iowa. The storm is directly to our West and we will turn W on the H3. However, the 3 in closed! Damn it – right, now heading S on the I75 and there is wicked CG with this thing.

19:29

Heading W again and NWS have just issued another warning for this storm. Golfbal sized hail now which means its intensifying.

19:39

TORNADO WARNING HAS BEEN ISSUSED FOR THE STORM THAT WE ARE HEADING TOWARDS. CG ALL OVER – THIS IS LOOKING VERY SCAREY INDEED. THE TORNADO IS MOVING E AT LESS THAN 10 MILES AN HOUR!!!

TORNADO IS 7 MILES SE OF VERMILLION. THIS IS OUT TO OUT SW. STILL IN PLY MOUTH COUNTY HEADING W ON H 3.

19:55

HEADING SOUTH ON THE H12 TOWARDS WESTFIELD IN PLYMOUTH COUNTY. STORM UPDRAFT OUT TO OUR WEST. HEAVY RAIN FALLING

20:22

IN ELK POINT, UNION COUNTY. SEVERE THUNDERSTORM HEADING IN THIS DIRECTION WITH HOPEFULLY THE SW FLANK WILL PASS TO OUR NORTH.

WE ARE 20 MILES SE OF VERMILLION, SKY TURNING GREEN – AMAZING CG ALL OVER THE PLACE. STORM HEADING IN OUR DIRECTION.

21:00

This would have to be the most amaxing light show I have ever seen. CG and CC lightning up the sky like a strobe - it is the most intense lightning I have ever seen.

22:15

Found hotel - also the tour company extreme winds have found the same hotel. Will post pics as soon as I can. CG going off right now!

[Guest ChaserUK]

well its 00:10 here and more storms seem to be developing all around me. Just seen more lightning - I think this might be a long night. Will post pics in the morning so about 2/3 in the afternoon your time.