National Weather Service Weather Forecast Office

 

 

Highest Temperature:

96 degrees on July 17^th and July 31^st

 

Lowest Temperature:

 -11 degrees on February 18^th

 

Most Precipitation in One Day:

1.71” on April 20^th

 

Most Snowfall in One Day:

10.7” on December 1^st

Temperatures:

            Highs:

January 19^th (53)

February 14^th (59t)

 April 13^th (83)

May 28^th (93t)

December 17^th (50t)

 

            Lows:

None

 

            Highest Lows:

May 28^th (69)

November 27^th (50)

November 28^th (53)

December 31^st (40t)

 

            Lowest Highs:  

None

 

            Monthly:

2^nd Warmest January

9^th Coldest October

 

            Seasonal:

None

 

Yearly:

11^th Warmest Year (50.6)

 

Precipitation:

            One Day Precipitation:

January 28^th (0.93”)

February 16^th (0.43”)

December 21^st (0.60”)

 

            Monthly Precipitation:

None

 

Seasonal Precipitation:

None

 

            One Day Snowfall:

October 11^th (Trace-t)

December 1^st (10.7”)

 

Monthly Snowfall:

None

 

            Seasonal Snowfall:

None

 

            Yearly:

None

 

 

The year started off very warm and ended up being the 2^nd warmest January in Rockford’s history. Every day during the month was above normal for the average temperature. Of note were the unseasonably warm overnight temperatures as the minimum temperature rarely even got into the teens (only 5 times all month). The average temperature for the month ended up being over 14 degrees above the norm for January. The main precipitation event of the month occurred on January 20^th when a developing system created an intense band of snow and thundersnow. Snowfall rates were very high and most of the snow fell within a 6 hour period during the evening hours. Some stations reported 13 inches of snow in 6 hours. The line between snow and rain pretty much split the region, as most of the northeastern counties in Illinois had rain/sleet/snow mix through most of the early portion of the event and ended up with a few inches. Rockford officially ended up with 5.0” of snow for the event. On the whole, precipitation for the month was above normal (twice as much as the normal amount) for the first time since February 2005!

 

February was the month where all the storm systems seemed to go to our north, leaving the region without much snowfall to speak of. The most notable case was on the 16^th where a frontal boundary set up just to the south of the region. Severe weather was reported in the area, with a possible tornado touchdown in Iroquois county (Wisconsin had thundersnow and blizzard conditions on this day). After this event, high pressure settled in for the rest of the month and created dry conditions. The average temperature and precipitation amount for the month was right around average, but snowfall was once again below normal. The highest temperature for the month was 59 degrees on Valentine’s Day.

 

The month of March was very average for temperatures, but well above normal for precipitation. The average maximum temperature was 0.4 degrees above normal, the average minimum temperature was 1.3 degrees above normal, the average temperature was 0.9 degrees above normal, and snowfall was 0.6 inches above normal. The amount of precipitation that fell during month was well above normal with 1.66 inches of surplus precipitation. There was a severe weather event on Sunday, March 12^th. Quite a bit of hail was reported with this system and some damage was reported in the Bridgeview area which may have been caused by a microburst. With the near normal precipitation conditions and no snow pack to melt, the drought continues on for most of northern Illinois. The highest temperature for the month was 66 degrees on the 11^th and the lowest temperature was 14 on the 4^th and 7^th.

 

April was a fairly warm month (12^th warmest ever) with quite an active severe weather pattern. The main severe weather events occurred on the 2^nd (mainly a hail event, with a few reports of damage from winds and F0 tornadoes), the 13^th into the 14^th (large hail) and Easter Sunday (a few Tornadoes). There was also substantial flooding with the storms on Easter with some reports of 3 to 5 inches or more in some areas. Rockford was well above normal for precipitation for the second month in a row. At this point of the year, the precip is over 3.50” in surplus of the average. Rockford was dropped from D2 severe drought conditions down to D0 which means abnormally dry. A record high of 83 was set on the 13^th as well as a snowfall record of 0.3” on the 13^th, but that precipitation came down as hail.

 

Temperature and precipitation wise, May ended up being as normal a month you can get. A cut-off low pressure system was stuck in the western Great Lakes for about a week and a half and created quite a cool streak during the middle part of the month. It also created a bit of wet streak, as there was precipitation of a trace or more on 11 days in a row. Even though there were a lot of days with rain, the amounts tended to be small. As the low moved on, the atmosphere went back toward normal and beyond. The warmest temperature of the month occurred on the 28^th with a high of 93, which tied the previous record. A record high minimum was also set on the 28^th with a low of 69. There were a few severe episodes, mainly with pulse thunderstorms. One tornado occurred in Kankakee County, 3 miles south of Aroma Park and was rated an F1. Flooding also occurred in most of the counties in northern Illinois on the 24^th, 29^th, and 30^th.

 

June was a very normal month for temperatures, but rather dry for precipitation. The average temperature for the month was 1.2 degrees below normal and precipitation was 1.48” below normal. There were severe thunderstorm events on the 2^nd, 17^th, 19^th, 21^st and 26^th. Probably the most notable event of the month was a heavy rain event that occurred during the overnight hours of the 25^th into the 26^th. There were no tornadoes that occurred during June and no records were broken. The warmest temperature of the month was 90 degrees on the17th and the coldest temperature was 45 degrees on the 12^th. The most precipitation in one day occurred on the 10^th when 1.52” fell (1.93” fell from the 9^th thru the 11^th).

 

The main weather story in July was the two heat waves that we went through. The first wave of 90+ temperatures occurred from about the 13^th through the 17^th. The warmest day during this period was the 17^th when the high got to 96 and the low only fell to 71. The second heat wave was longer and lasted into August. The warmest part of this heat wave came on the 31^st where the high temperature was 96 degrees.   With the warm weather, severe winds were prevalent whenever a cold front would push through to cool things off. There were no tornadoes during July.

 

The beginning of August brought the end of the 2^nd heat wave in the region. The highest temperature of the month occurred on the 1^st at 94 degrees, while the lowest temperature of the month came later in the month on the 21^st (52 degrees). A squall line went through early in the morning on the 3^rd that created quite a bit of tree damage from Lee County all the way to downtown Chicago. Another round of morning severe storms rolled through on the 10^th with some winds estimated at 70 mph. After the heat wave ended, temperatures returned to being more normal, but precipitation was scarce for the month until the last week.   Farmers had been having problems with their crops and the grass was brown and dying. 3.03” of the month’s 3.55” fell in the last week of the month to help with the abnormally dry conditions. Unfortunately, this was a sign of things to come in early September.

 

This was the 5^th month in a row that was below normal for precipitation, even though heavy rain fell on Labor Day that left a portion of the city of Rockford under water. Rainfall amounts were lighter at the airport than they were downtown where about 3 to 4 inches of rain fell in a rather short amount of time. This was in a very skinny band of rain that trained over the same area. A very strong rotation was also evident on radar as well as from trained weather spotters with the main storm. No tornados ever developed from the storm however. No records were set during September and the temperatures were 2.0 degrees below normal for the month. 

 

The biggest event for the Rockford area in the month of October was the early season snowfall that happened on the 11^th and 12^th. A quick snow shower fell in the late evening of the 11^th lead to a trace of snow at the airport. This tied a record for the most snow on that day. The main show came early in the morning on the 12^th. Although the airport at Rockford only received a Trace of snow this day, a small band of snow developed along the north side of the city and extended through a portion of northern Illinois. Snowfall amounts of 1.0” to 2.0” were recorded throughout the area. This snow happened to coincide with the morning commute, so the early season snow caught some people off guard and caused a few car accidents. While most of northern Illinois had an active severe weather day on the 2^nd, the Rockford area was mainly out of danger’s way on this day. Cold Canadian air persisted across the region for the second straight month, which leads to this October being the 9^th coldest on Rockford’s record. 

 

For the most part of the month, temperatures were below or near normal with a few exceptions at the beginning and end of the month when temperatures were well above normal. Two records were set for warmest low temperatures on the 27^th and 28^th when temperatures didn’t drop below 50. The first warm streak ended abruptly on the 10^th when a strong cold front came through and brought thunder and lightning to the region with thunderstorms out ahead of the front even though temperatures were in the mid 30s. The second warm spell came to an end on the last day of the month as a cold front pushed through, dropping temperatures into the 20s right before snow started on the 1^st of December. Most of the precipitation for the month fell on three days. The first was on the 10^th with the aforementioned front and the other two days were on the 28^th and 29^th before the end of the second warm streak.

 

December 2006 had a lot of similarities to December 2005 due to a snowstorm in the beginning part of the month, followed by a cold spell for about a week and a half, followed by above normal temperatures the rest of the month. The heaviest snowfall of the year came on the 1^st when a swath of 6-13 inches of snow fell across northern Illinois. The snow fell mainly during the morning rush hour on that Friday, but due to the advance warning, most people took off from work or had school cancelled in advance. This Christmas was once again not white, but above normal for temperatures again with no snow cover left from the early snowstorm. Six records were broken during the month: Highest Temperature on the 17^th, most precipitation on the 21^st, and most snowfall on the 1^st (which also was the highest amount of snow to fall on one day in the month of December in Rockford’s history). With the warm end to the month, the High Minimum Temperature records were broken on the 29^th, 30^th and 31^st.

 

Tim Halbach

Climate Focal Point

NWS Chicago