Top 10 Weather Events - 2006

Top 10 Weather/Climate
Events in 2006

Here is a listing of the Top 10 Weather Events for 2006 in the NWS La Crosse Warning and Forecast Area. This includes areas of southeast Minnesota, northeast Iowa, and southwest/central Wisconsin.

This listing is the result of voting among NWS La Crosse staff members (10), Emergency Managers (5), and members of the media (9).

Updated: 1/03/07 - jsb

For additional information, contact:

Todd Shea, Warning Coordination Meteorologist, or
Jeff Boyne, Climate Services Focal Point

Honorable Mention: October Temperature Extremes

The month of October started out quite warm, with temperatures in the 80s around for the first three days (leading to severe weather - see #10). On October 2nd, both La Crosse, WI and Rochester, MN hit 84 deg F.

Only 10 days later, temperatures were averaging 20 deg F below normal with highs only in the 30s. The month finished 2-6 deg F colder than normal, ranking as the 13th coldest on record at Rochester, MN and 18th coldest for La Crosse, WI.

Honorable Mention: July 19-20 Severe Storms

Severe Thunderstorms tracked across the region over a two day period producing widespread high wind gusts and sporadic large hail reports. Wind gusts up to 70 mph were common across northeast Iowa with the storms.

As the storms tracked into southwest Wisconsin they began to weaken but were still strong enough to knock down trees killing a 6-year old girl who was sleeping in a tent overnight. A total of 15 severe weather warnings were issued.

	Click on image to enlarge. Doppler Radar view of the storms around 3:14 a.m. CDT July 20th when storms were moving through Grant Co., Wisconsin.
	Click on image to enlarge. Severe weather reports received from July 19th into the early morning hours of July 20th. (Image courtesy of Storm Prediction Center.)

Click here - for a listing of 2-day (July 19-20) rainfall totals.

10. October 2-4 Severe Storms mean cloud icon

Warm weather during the start of the month led to several rounds of severe thunderstorms. The biggest impact from them was large hail. Each round of storms shifted south in time leading to the issuance of 22 severe weather warnings.

	Click on image to enlarge. Doppler Radar view of the storms around 8:46 p.m. CDT October 3rd when storms were dropping large hail (up to 2" in diameter) around Osseo, WI (between Eau Claire and Black River Falls).
	Click on image to enlarge. Doppler Radar view of the storms around 3:56 a.m. CDT October 4th when storms were dropping hail as large as baseballs over Mitchell Co., Iowa.
	Click on image to enlarge. Severe weather reports received from October 3rd. (Image courtesy of Storm Prediction Center.)

9. February 15-16 Snow Storm snowman

A potent winter storm dropped 5-9 inches of snow across most of the region. In addition strong winds behind the storm caused significant blowing and drifting and dangerous wind chills. Numerous record low temperatures were set after the storm and new snow cover.

The highest snowfall totals were 9 inches reported at La Crosse and Black River Falls, WI, along with the Caledonia, MN area and Dorchester, IA. On February 18th, low temperatures of -19 deg F were reported at Rochester, MN, -21 at La Crosse, WI, and -31 deg F near Necedah, WI. A low of -26 deg F in Elkader, IA (Fayette Co.) on the 18th ended up being the coldest temperature recorded in Iowa for the year.

Daily snowfall records were established at both Rochester, MN (6.6") and La Crosse, WI (8") on February 16th.

Click here - for a summary of the storm.

Click here - for a graphic of snowfall in Wisconsin on Feb.15-16.

8. April 13 Hail Storms mean cloud icon

Severe thunderstorms developed across eastern Iowa during the early evening of April 13th. One cluster of storms produced significant tornado damage (including a fatality) in and around Iowa City, Iowa. Another cluster of storms tracked northeast into southwest Wisconsin producing long-lived, large hail.

Numerous hail reports up to baseball size were reported from Grant County, WI with considerable property damage. A total of 11 warnings were issued.

These storms tracked across the rest of southern Wisconsin and produced the most costly storm day in Wisconsin's history with damage estimates topping 160 million dollars.

	Click on image to enlarge. Doppler Radar view of the storms around 8:29 p.m. CDT April 13th when storms were dropping large hail over Clayton Co., Iowa and Grant Co., Wisconsin.

Click here - For a summary of the event from NWS Davenport.

Click here - For a summary of the event from NWS Milwaukee/Sullivan.

7. Low Number of Tornadoes tornado icon

Only 1 tornado was reported in the La Crosse National Weather Service forecast and warning area during 2006. This also happened in 2003, but is far below the average of 8 per year. Since January 2004 there had been 34 tornadoes.

The only tornado in 2006 was near Richland Center, WI on May24th. It was rated an F0. Click here - for the news story on this event.

	Click on image to enlarge. Doppler Radar view of the storms around 4:56 p.m. CDT May 24th as a small tornado passed just south of Richland Center, WI.
	Click on image to enlarge. Tree damage from the only reported tornado in 2006 - approx. 2 miles south of Richland Center, WI.

There were several outbreaks when tornadoes struck in parts of eastern Iowa or central Minnesota, but in nearly every case the air remained just stable enough further east to preclude tornado development.

Overall, tornado numbers were down this year in nearby states and nationally. Wisconsin only had 13 total tornadoes (compared to 62 in 2005) and well below the state annual average of 21. In Iowa, there were no tornadoes in May 2006 at all (first time since 1978) and only three reported in June. The total in Iowa for 2006 was 38 tornadoes (average is 47).

6. Lack of December Snow / Warm Weather

December 2006 went into the record books as one of the least snowiest Decembers on record in many locations in northeast Iowa, southeast Minnesota, and southwest, west central, and central Wisconsin. La Crosse, WI received just a trace of snow (which tied 1943 and 1979 for the least snow in a December) and Rochester, MN received just eight tenths of an inch of snow which placed December 2006 in fifth place for the least amount of snow in a December.

The combination of lack of snow and El Niño (which typically results in above normal temperatures for the Upper Mississippi River Valley) has resulted in December 2006 being unusually warm. During December, temperatures were 6 to 12 degrees above normal across southeast Minnesota, northeast Iowa, and western Wisconsin. The greatest departure from normal was in Rochester where temperatures were 11.7 degrees above normal (average temperature 29.0 degrees). This was their fourth warmest December. La Crosse Municipal Airport had an average temperature of 30.8 degrees which was 9.0 degrees above normal. This was their tenth warmest December and their warmest December since 1931.

NOTE: 2006 finished in the Top 5 for warmest years on record at many locations. Rochester, MN had an average temperature of 47.6 degrees which was 4.2 degrees above normal. This was their 2nd warmest year. La Crosse, WI had an average temperature of 49.8 degrees which was 2.5 degrees above normal. This tied 1999 for their 5th warmest year.

	Click on image to enlarge. Snowfall departure from normal during December 2006. (Image courtesy of The Midwestern Regional Climate Center.)
	Click on image to enlarge. Temperature departure from normal during December 2006. (Image courtesy of The Midwestern Regional Climate Center.)

5. July Heat thermometer icon

Warm, dry conditions kept temperatures 2-5 deg F above normal during July in 2006. In La Crosse, WI it was the warmest month since July 1980. It was the seventh warmest month on record (warmest was July 1936 when the average temperature in La Crosse was 79.5 deg F).

Temperatures were warmest through the end of the month and continued into early August. On July 31st, La Crosse hit 102 degrees, the hottest since July 14, 1995 when the high temperature was 103.

	Click on image to enlarge. Temperature departures from normals during the last week of July 2006. (Image courtesy of The Midwestern Regional Climate Center.)
	Click on image to enlarge. Temperatures recorded around the State of Wisconsin on July 31, 2006. (Image courtesy of NWS Milwaukee/Sullivan)

4. Drought sun icon

Very dry and above normal temperatures from mid May to mid July resulted in the development of drought conditions across parts of western and northern Wisconsin. The drought was worse across north central and northwest Wisconsin where severe (D2) to extreme (D3) conditions existed. Surrounding this area, there was an area of moderate drought (D1) conditions which extended south into parts of west central and central Wisconsin.

Click on image to enlarge. US Drought Monitor graphic valid July 25, 2006 - near the peak of the worst drought conditions.

Federal disaster assistance was required for several counties due to widespread crop losses.

From late summer into early autumn, above-normal rains and below-normal temperatures developed across the area resulting in a quick recovery.

3. November 10th Snow Storm snowman icon

An early season snow storm brought significant snow to parts of southeast Minnesota into north central Wisconsin. Nine to twelve inches of snow was common from around Austin, MN to Wausau, WI. A report of 16.5" was logged from Osseo, WI while Rochester, MN had 10.4" making it the greatest one-day November snowfall since 1952 (10.6").

Click here - for a summary of the November 10, 2006 winter storm.

Click on image to enlarge. Doppler Radar view of the heavy snow during the morning of November 10th. The main axis of heavy snow is circled.

2. August 23-25 Severe Weather mean cloud icon

A very active weather pattern set up in late August. During this three day stretch (August 23-25), five rounds of severe weather pelted the region totaling nearly 160 severe weather reports and prompting 74 warnings. (The most active stretch of severe weather since June 1998.) Nearly all the hazardous weather was across southeast Minnesota and western Wisconsin with several rounds of golf ball size hail and winds gusting to 80 mph at times (Rochester Int'l Airport [RST] had a peak wind gust of 74 mph).

Crop and property damage was extreme. Damage to cranberries in western Wisconsin was in excess of 8 million dollars and numerous mobile homes were damaged near Stewartville, MN. Even flooding was reported which prompted the closing of Interstate 90 in Austin, MN.

Click here - for a full summary of the August 23-25, 2006 Severe Weather Outbreak from NWS La Crosse.

Click here - for a full summary of the August 24 tornado outbreak across south central Minnesota from NWS Minneapolis/Chanhassen.

	Click on image to enlarge. Doppler Radar view of the storms around 8:30 p.m. CDT August 24th near the time significant wind gusts hit the Rochester Int'l Airport ((RST) and Stewartville, MN areas.
	Click on image to enlarge. Severe weather reports received from August 23rd. (Image courtesy of Storm Prediction Center.)
	Click on image to enlarge. Severe weather reports received from August 24-25. (Image courtesy of Storm Prediction Center.)

1. January Record Warmth / Lack of Snow

Temperatures were well above average in January 2006 averaging 13 to 17 deg F above normal and setting new records along the way. Rochester, MN averaged 28.1 degrees (16.3 degrees above normal) surpassing the previous record of 25.8 deg F. La Crosse, WI averaged 31.1 degrees over this period making it the second warmest January on record. Low temperatures only made the single digits twice during the entire month.

In Iowa, January 2006 tied (with 1933) for the warmest January among 134 years of record.

Along with the record warmth, there was a record lack of snow. Rochester, MN only had 0.8" of snow - their lowest ever in a January. On average, Rochester gets 11.1" of snow in the month of January. La Crosse, WI tied for least snow ever in a January with 1.6" (Also back in 1903) but on average should get 12.9" of snow.

	Click on image to enlarge. Temperature departures from normals during January 2006. (Image courtesy of The Midwestern Regional Climate Center.)
	Click on image to enlarge. Temperature statewide ranks for January 2006. 112 is warmest on record (112 years).

Links to previous Top 10:

National Weather Service Weather Forecast Office