Heavy Rain Possible This Week

As first advertised last week, a cold front will pass through Colorado today/tonight.  Behind the front temperatures will drop to October-like levels.  Along with cooler air, monsoon moisture will be in place over Colorado.  Combine that with easterly winds creating an upslope flow, heavy rains will be possible.

Taste of Fall Coming to Colorado

After another warm afternoon with temperatures reaching the 90°s and lower 100°s we will see clear skies overnight with lows dropping to the 60°s.

Expect to see sunny skies across the plains of southeast Colorado, mostly sunny skies along the I-25 corridor and partly cloudy skies over the higher terrain west of I-25.  There is a small chance for an isolated shower/thunderstorm in Teller County and some of the mountains.  Highs will be in the 80°s to near 100° across southern and southeast Colorado.  Some of the warmer temperatures will occur along the U.S. 50 corridor.

Computer models continue to advertise a cold front moving through Colorado Tuesday.  Ahead of the front there could be a few scattered showers and thunderstorms.  Along, and especially behind the front, there will be a chance for showers and thunderstorms.  Also, cooler temperatures will move in to parts of Colorado.  I am currently forecasting high temperatures to be in the 60°s to 70°s Wednesday.

The fall weather-tease will be short lived.  By the end of next week temperatures will climb back to above normal level.  - Meteorologist John Dissauer

FRIDAY'S NORMALS:

Colorado Springs:
High: 78°
Low: 51°
Precipitation: 0.05"

Pueblo:
High: 85°
Low: 52°
Precipitation: 0.03"

Taking Aim at the Long Range

It is always interesting and fun to see what computer models are suggesting for the long range.  I'm not talking five to eight days out, instead twenty to thirty days out.

There are a couple computer models that try to stick their arms waaaaaay out to look that far.  One of the forecast models, the European Forecast Agency's computer model, is a model that attempts to look out thirty days.  I have access to data that updates once a week.  Going forward I am going to try to take a look at the model and post observations here on "New at Dis Hour".

Here are a few observations from last week's run of the European.

• Above normal temperatures for Colorado Sept 14-20.
• Below normal temperatures for the Midwest September 12-14 and September 16-20.
• Northwest flow dominates weather pattern September 25-28 from the Rocky Mountains to the Midwest.  (Northwest flow often means there could be storms developing in the NW US and they would quickly dive to the SE.  Also often produces below normal temperatures.)
• Heat builds back in to Colorado October 1-3.

Keep in mind, the model is just that.  A computer model.  The farther out the model looks, the higher the error rate.  The key to looking at this kind of data is to not look at specifics but instead trends and long wave patterns.

Meteorological Summer 2013 - Missouri

Meteorological Summer has come to an end and the final numbers are in.  How did Cape Girardeau and St. Louis fair?

*Meteorological Summer is June, July and August.  You are correct, it does not match up with calendar summer.  Meteorologists split the year in to four equal section.  Meteorological Spring is March, April, May.  Meteorological Summer is June, July, August.  Meteorological Fall is September, October, November.  Meteorological Winter is December, January, February.

Summer 2013 in Cape Girardeau broke the trend of the last couple of years as it came in on the cool side.  Officially, the city finished the summer 3.6° below normal.  Only thirty-nine days were above normal (42%).  The majority of the rain came early in the season which helped bring Cape Girardeau to 2.11" above normal.

CAPE GIRARDEAU:
June:

• Temperature: +0.7°
• Number of Days Above Normal (Temperature): 16
• Precipitation: +4.19"

July:

• Temperature: -2.8°
• Number of Days Above Normal (Temperature): 13
• Precipitation: -2.59"

August:

• Temperature: -1.5°
• Number of Days Above Normal (Temperature): 10
• Precipitation: +0.51"

After Summer 2012's scorching heat St. Louis finally had a summer that was closer to the norm.  Officially at Lambert Airport the city finished Summer 2013 1.9° below normal.  Only forty-one days (45%) of the days were above normal.  Interestingly, St. Louis finished the summer 0.91" below normal as far as precipitation.  I say "interesting" because typically when you have a summer period below normal you will have above normal rain.

ST. LOUIS:
June:

• Temperature: +0.1°
• Number of Days Above Normal (Temperature): 15
• Precipitation: +1.65"

July:

• Temperature: -2.1°
• Number of Days Above Normal (Temperature): 12
• Precipitation: -0.76"

August:

• Temperature: +0.1°
• Number of Days Above Normal (Temperature): 14
• Precipitation: -1.80"

Meteorological Summer 2013 - Colorado

Meteorological Summer has come to an end and the final numbers are in.  How did Colorado Springs and Pueblo fair?  Let's take a closer look and see how the numbers break down.

*Meteorological Summer is June, July and August.  You are correct, it does not match up with calendar summer.  Meteorologists split the year in to four equal section.  Meteorological Spring is March, April, May.  Meteorological Summer is June, July, August.  Meteorological Fall is September, October, November.  Meteorological Winter is December, January, February.

Summer 2013 in Colorado Springs was a warm one.  Officially, the city finished the summer 7.4° above normal.  67% of the days (62) were above normal.  Interestingly, heavy rains also came with the warmer than normal summer.  The city finished summer 2.25" above normal.

COLORADO SPRINGS:
June:

• Temperature: +4.9°
• Number of Days Above Normal (Temperature): 25
• Precipitation: -1.90"

July:

• Temperature: +0.4°
• Number of Days Above Normal (Temperature): 16
• Precipitation: +1.77"

August:

• Temperature: +2.1°
• Number of Days Above Normal (Temperature): 21
• Precipitation: +2.38"

Similar to Colorado Springs, Pueblo had a warm summer.  Officially, Pueblo finished Summer 2013 6.6° above normal.  Sixty-three days were above normal (68%).  The city also finished the summer above normal when it comes to precipitation.  Officially 0.13" above normal.

PUEBLO:
June:

• Temperature: +4.3°
• Number of Days Above Normal (Temperature): 26
• Precipitation: -1.09"

July:

• Temperature: +0.5°
• Number of Days Above Normal (Temperature): 18
• Precipitation: -0.38"

August:

• Temperature: +1.8°
• Number of Days Above Normal (Temperature): 19
• Precipitation: +1.60"

Heat Taking Aim on Central US

The big weather story this week continues to be the heat taking aim on the central United States, including eastern Colorado.

An area of high pressure in the upper-levels of the atmosphere has taken residence over the central Plains.  Temperatures under and near the high have climbed in to the 90°s and in some cases 100°s.  Along with the high temperatures, humidity is high across the central U.S.  Heat indices (the feels like temperature) hace climbed to near 110° as far north as Minnesota.

The upper-level high will slowly move east over the next 48 hours.  Eventually, it will begin to retrograde to the west.

As the upper-level high controls the weather pattern over eastern Colorado, monsoon moisture will remain over Arizona and Utah.  Later this week some of the moisture will begin to return to the mountains of southern Colorado and eventually the I-25 corridor.  I introduce a chance for isolated showers and thunderstorms for places like Canon City and Woodland Park starting Wednesday.

LABOR DAY WEEKEND

As of now, computer models are suggesting there will be enough moisture around southern/southeastern Colorado for there to be a chance of showers and thunderstorms.  Also, with the moisture around, skies will be partly to mostly cloudy, especially for areas closer to the foothills.  Temperatures will also be held down due to the clouds and showers/thunderstorms.  Highs will likely be in the 80°s.

TUESDAY'S NORMALS

Colorado Springs:
High: 80°
Low: 54°
Precipitation: 0.09"

Pueblo:
High: 88°
Low: 56°
Precipitation: 0.06"

Late Season Heat Wave

The big weather story this week is a late season heat wave taking aim on the central United States.  Record high temperatures could fall anywhere from Colorado to Indiana.

An upper-level high pressure dome will setup shop over the middle U.S. early this week.   High pressure aloft allows for air to sink and compress.  When air compresses, it increases in temperature.

Temperatures will reach the century mark. Temperatures in southern and southeastern Colorado will top out in the upper 80°s to lower 100°s through Friday.

Computer models suggest that the heat should begin to ease for the central Plains around September 1 and models suggest the heat could continue through at least Labor Day Weekend for the Midwest.

The upper-level high will initially push monsoon moisture west in to western Arizona and Utah and take it away from southern/southeastern Colorado. Later in the week moisture will begin to come back to Colorado. The moisture will allow for a chance for isolated showers and thunderstorms over the mountains west of I-25 starting Wednesday.

As for Monday, expect to see mostly sunny to partly cloudy skies across the KOAA viewing area. Highs will top out in the upper 80°s to upper 90°s. Colorado Springs should top out at 88° and Pueblo should see a high temperature of 95°.

MONDAY'S NORMALS:

Colorado Springs:
High: 80°
Low: 54°
Precipitation: 0.09"

Pueblo:
High: 88°
Low: 56°
Precipitation: 0.06"

Heavy Rains to Southern Colorado

Here is a closer look at what to expect Wednesday afternoon through Thursday evening.

Heavy rain will be possible through Thursday night.  Flash Flood Watches are in effect through Thursday.