Large, violent tornado hits Austin (injuries reported)

Update: 9:20 pm. Series of Doppler radar images showing severe rotation west of Stewartville. The image below shows a reflectivity display. Note the extreme wind shear causing the tornadic cell to "tilt" over to one side, to the right of the general motion of upper level winds (west/northwest or 290 degrees).


Tornado watch for much of southern MN (does NOT include Twin Cities) until 1 am Thursday morning. At least 6 tornado touchdowns in Minnesota (as of 9:00 pm). The most notable: large, violent tornado hits the Austin area with reports of damage & injuries, possibly a "multi-vortex" tornado with multiple funnels rotating around a common center/wall cloud. The lingering threat is greatest east of Owatonna and Austin, toward Stewartville, Rochester, Cannon Falls and the Winona area. Residents of far southeastern MN should stay alert and stay tuned for possible warnings.

(Click on the image to bring it full screen and read the tornado warning text for the Owatonna area).

Update: 9:00 pm. Reports of a large, damaging tornado in the Austin area, and the threat is not over yet. Cars have been flipped over in the Austin area with injury reports and considerable debris. Power is out throughout the city. The highway leading north of Austin has been closed down because of the tornado. A "multivortex" tornado (several tornadoes all spinning around a common center) was observed with this supercell thunderstorm. Tornadoes often form in "families", one tornado touches down, matures and then dies out. Minutes later the same parent thunderstorm spawns a second tornado farther south/east, in the warm, humid air, unaffected by rain/hail-cooled air. This process can continue for many hours, resulting in multiple tornadoes from the same supercell thunderstorm.

Update: 8:30 pm. Funnel clouds spotted near Waseca.

* Greatest tornado risk: Austin area. Large tornado on the ground, impacting northern/eastern suburbs of Austin area!

* Tornado warnings posted for southeastern MN counties through the evening hours.

* Greatest risk near Owatonna, Faribault, Austin and Rochester/Stewartville area.

* Strong/severe storms may move into the Twin Cities metro area later tonight - conditions ripe.

* Computer models print out some 1-2" rainfall amounts over the next few days, potential for tropical dew points.

* First Minnesota tornado of the year touches down in Wilkin county (far west central MN) around 4:40 pm. No reports of injuries/damage.

8:34 pm (Greatest threat appears to be just east/northeast of Austin, tornadic supercell moving toward Elkton and Dexter area).




SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE LA CROSSE WI
817 PM CDT WED JUN 17 2009

MNC099-180215-
/O.CON.KARX.TO.W.0009.000000T0000Z-090618T0215Z/
MOWER MN-
817 PM CDT WED JUN 17 2009

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 915 PM CDT FOR MOWER
COUNTY...

AT 814 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR AND STORM
SPOTTERS WERE TRACKING A LARGE AND EXTREMELY DANGEROUS TORNADO. THIS
TORNADO WAS LOCATED NEAR I 90 EXIT 181...OR NEAR AUSTIN...MOVING
SOUTHEAST AT 35 MPH. IT APPEARS THIS TORNADO WILL TRACK ACROSS THE
NORTH AND NORTHEAST SIDE OF AUSTIN.

IF YOU ARE IN THE PATH OF THIS STORM...YOU MUST GET INDOORS AND
UNDERGROUND IN A BASEMENT. DO NOT STOP UNDER HIGHWAY
OVERPASSES...SEEK SHELTER IN A BUILDING OFF THE HIGHWAY.

* THE TORNADO WILL BE NEAR...
I 90 EXIT 183 AND RENOVA AROUND 820 PM...
ROSE CREEK AND I 90 EXIT 187 AROUND 825 PM...
ADAMS AROUND 835 PM...
GRAND MEADOW AROUND 840 PM...
HIGHWAYS 63 AND 16 AROUND 850 PM...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

CARS AND MOBILE HOMES SHOULD BE ABANDONED FOR A STURDY BUILDING. AS A
LAST RESORT...LAY FLAT IN A DITCH AND COVER YOUR HEAD.




SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
817 PM CDT WED JUN 17 2009

MNC131-147-161-180130-
/O.CON.KMPX.TO.W.0008.000000T0000Z-090618T0130Z/
RICE MN-WASECA MN-STEELE MN-
817 PM CDT WED JUN 17 2009

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 830 PM CDT FOR NORTHERN
STEELE...NORTHEASTERN WASECA AND EXTREME SOUTHWESTERN RICE
COUNTIES...

AT 815 PM CDT...A FUNNEL CLOUD WAS REPORTED NORTHEAST OF WASECA.

AT 816 PM CDT... THE TORNADIC SEVERE THUNDERSTORM WAS LOCATED 5 MILES
EAST OF WASECA...OR ABOUT 6 MILES SOUTH OF DEERFIELD...AND MOVING
EAST AT 20 MPH.

THE TORNADO WILL BE NEAR...
OWATONNA BY 830 PM CDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IF YOU ARE CAUGHT OUTSIDE...SEEK SHELTER IN A NEARBY REINFORCED
BUILDING. AS A LAST RESORT...SEEK SHELTER IN A CULVERT...DITCH OR LOW
SPOT AND COVER YOUR HEAD WITH YOUR HANDS.

THE SAFEST PLACE TO BE DURING A TORNADO IS IN A BASEMENT. GET UNDER A
WORKBENCH OR OTHER PIECE OF STURDY FURNITURE. IF NO BASEMENT IS
AVAILABLE...SEEK SHELTER ON THE LOWEST FLOOR OF THE BUILDING IN AN
INTERIOR HALLWAY OR ROOM SUCH AS A CLOSET. USE BLANKETS OR PILLOWS TO
COVER YOUR BODY AND ALWAYS STAY AWAY FROM WINDOWS.



BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
716 PM CDT WED JUN 17 2009

THE NATIONAL WEATHER SERVICE IN THE TWIN CITIES HAS ISSUED A

* TORNADO WARNING FOR...
SOUTHERN STEELE COUNTY IN SOUTH CENTRAL MINNESOTA...
NORTHEASTERN FREEBORN COUNTY IN SOUTH CENTRAL MINNESOTA...

* UNTIL 800 PM CDT

* AT 715 PM CDT...RADAR INDICATED A DEVELOPING TORNADO. THE MOST
DANGEROUS PART OF THE STORM WAS 4 MILES SOUTHEAST OF STEELE
CENTER...AND MOVING EAST AT 15 MPH.

* LOCATIONS IN THE WARNING INCLUDE...
BIXBY...
BLOOMING PRAIRIE...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

WHEN A TORNADO WARNING IS ISSUED BASED ON RADAR...IT MEANS THAT
STRONG ROTATION HAS BEEN DETECTED IN THE STORM. A TORNADO MAY ALREADY
BE ON THE GROUND...OR IS EXPECTED TO DEVELOP SHORTLY.

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
716 PM CDT WED JUN 17 2009

THE NATIONAL WEATHER SERVICE IN THE TWIN CITIES HAS ISSUED A

* TORNADO WARNING FOR...
SOUTHERN STEELE COUNTY IN SOUTH CENTRAL MINNESOTA...
NORTHEASTERN FREEBORN COUNTY IN SOUTH CENTRAL MINNESOTA...

* UNTIL 800 PM CDT

* AT 715 PM CDT...RADAR INDICATED A DEVELOPING TORNADO. THE MOST
DANGEROUS PART OF THE STORM WAS 4 MILES SOUTHEAST OF STEELE
CENTER...AND MOVING EAST AT 15 MPH.

* LOCATIONS IN THE WARNING INCLUDE...
BIXBY...
BLOOMING PRAIRIE...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

WHEN A TORNADO WARNING IS ISSUED BASED ON RADAR...IT MEANS THAT
STRONG ROTATION HAS BEEN DETECTED IN THE STORM. A TORNADO MAY ALREADY
BE ON THE GROUND...OR IS EXPECTED TO DEVELOP SHORTLY.
BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
637 PM CDT WED JUN 17 2009

THE NATIONAL WEATHER SERVICE IN THE TWIN CITIES HAS ISSUED A

* TORNADO WARNING FOR...
SOUTHEASTERN WASECA COUNTY IN SOUTH CENTRAL MINNESOTA...
SOUTHERN STEELE COUNTY IN SOUTH CENTRAL MINNESOTA...
EXTREME NORTHEASTERN FARIBAULT COUNTY IN SOUTH CENTRAL MINNESOTA...
FREEBORN COUNTY IN SOUTH CENTRAL MINNESOTA...

* UNTIL 715 PM CDT

* AT 635 PM CDT...RADAR INDICATED A DEVELOPING TORNADO. THE MOST
DANGEROUS PART OF THE STORM WAS 4 MILES NORTHWEST OF HARTLAND...OR
ABOUT 4 MILES NORTH OF FREEBORN...AND MOVING NORTHEAST AT 10 MPH.

* LOCATIONS IN THE WARNING INCLUDE...
MANCHESTER...
HARTLAND...
ALBERT LEA...
NEW RICHLAND...
STEELE CENTER...
BIXBY...
HOLLANDALE...
HAYWARD...
GENEVA...
ELLENDALE...
CLARKS GROVE...
BLOOMING PRAIRIE...



** It's official. At 4:40 the first Minnesota tornado of the year touched down near Nashua, in Wilkin Country, far west central Minnesota - no reports of damage or injuries.



(Update: 5:05 pm. A tornado warning is posted for Grant, Otter Tail and Wilkin counties until 5:45 pm. People living in the Elbow Lake area are potentially in the path of this tornadic storm, which is producing 3/4 to 1"+ hail. As a rule the larger the hail the greater the potential for the same violent updraft spawning a tornado. The threat of severe weather will continue, spreading from west central into central Minnesota later this evening. Computer models suggest that storms will become even more widespread during the evening and early nighttime hours, spreading from west/north toward the east/southeast, reaching St. Cloud after 8 or 9 pm, into the Twin Cities by 11 pm or midnight. Most of us will NOT see anything severe, but isolated reports of damaging hail, straight-line winds over 70 mph, and an isolated tornado [first of the year in Minnesota] can't be ruled out).
(Latest Supercell Composite Index from SPC, the Storm Prediction Center. The greatest risk of severe "supercell" thunderstorms is over far southwestern MN and much of central and western Iowa this afternoon. With murky sun, a very unstable airmass, and sufficient wind shear aloft conditions seem ripe for strong/severe T-storms. A tiny percentage may produce large, damaging hail, damaging straight-line winds, even an isolated tornado. The greatest threat of violent weather appears to be south/west of the Minnesota River, including Albert Lea, Mankato, Worthington, Jackson and Windom later today. Although the greatest risk appears to be across southern Minnesota, a few strong to severe storms may form over central Minnesota, from St. Cloud to the Twin Cities area - the best chance of severe weather coming from 4 to 7 pm. Stay alert, and check in often for possible warnings later today. It's entirely possible that Minnesota will see it's FIRST tornado touchdown of the year later today).
(Midday visible satellite image showing some hazy, murky sun breaking through over much of southwestern Minnesota. This is important, because any heating of the ground and the air immediately above the ground will increase the instability of the airmass over the southern third of Minnesota, increasing the potential for severe storms later today).

(Probability of a tornado touchdown within 25 miles of any point - a 5% risk for much of southwestern and central Minnesota. Many of the ingredients for isolated tornado-producing, supercellular thunderstorms are present. I do expect watches and warnings across parts of central and southern Minnesota later today. Stay tuned).

Summer Clouds

Image credit Pekka Parviainen

Did you know that weather on earth forms in the lowest layer of the atmosphere called the troposhpere? Cloud formation comes in many makes and models in this layer: Cumulus (low clouds), Alto (middle clouds) and cirrus (high clouds).

Here's a nice visual from Enchanted Learning:
Cumulonimbus clouds are the tallest clouds in the troposphere, which can grow to a height of nearly 12 miles high or more (60,000 ft.)
Image courtesy NASA's Earth Observatory. This picture was taken high above Africa looking down at at thunderstorm towering to nearly 12 miles high.

Have you ever wondered what the names of clouds mean. Here are some Latin cloud meanings from the weather notebook:

So, now that I've given you an overview of typical cloud formations, take a look at this video:

These are called NLC's or "noctilucent clouds" and I've actually never seen these. They are very rare and only happen during the summer months in the northern hemisphere and occur during twilight. First, take a look at this graphic: (Just mouse over the different objects to get a quick description)

What layer do you think noctilucent clouds form in?

If you said Mesosphere, you were correct!

Noctilucent clouds are the highest cloud in the Earth's atmosphere, developing around 50 miles high - the same layer that shooting stars appear. Because they are so high, they are visible long after the sun disappears below the horizon.
Image courtesy NASA

These clouds are still somewhat of a mystery to scientists, but some speculate these clouds form due to ice crystals/water vapor from space shuttles.

Read this report by NASA:

Space Shuttle Endeavour is set to lift off early Wednesday morning after a hydrogen leak postponed their launch on Saturday June, 13th. Here's the bad news, if they get off the ground Wednesday, they will have to wait until mid-July. If you'd like to follow their mission, check out Endeavour Astronaut Mark Polanski as he TWEETS from space:
Weather Headlines

* Damp start. Break in the showery pattern Wednesday midday into Thursday afternoon.

* Next chance of organized showers comes late Thursday into Friday. Some storms may be strong to severe. The Storm Prediction Center has MN and WI under a slight risk of severe weather.

* Saturday rain may linger over Wisconsin, clouds and showers can't be ruled out over far eastern Minnesota. Overall, the weekend is looking drier and warm

*Sunday (Father's Day) showers and storm return late

* Long-range guidance: highs mostly in the 80s the last full week of June. No more cold fronts in sight.

Todd's Outlook

Today: damp start, then becoming partly sunny with an unsettled afternoon sky. High: 78

Tonight: Another round of showers and storms slides into western Minnesota. Low: 61

Thursday: Partly sunny. Showers and storms developing late in the day, some strong to severe. High: 80

Friday: Unsettled with a few widely scattered showers or storms. High: 78

Saturday: Drying out. Sunshine returns with June-like temperatures. High: 81

Sunday: Sunny start, clouds increase late with showers and storms by evening. High: 83

Monday: Partly sunny with a chance of scattered showers and storms. High: 83

Tuesday: Still unsettled, getting warm and muggy. High: 85