Long Range Weather Outlook Sept 28 - Oct 28

Just sat down and took a look at the latest data from the experimental loooooooong range computer model.  The computer model looks out over roughly the next 30 days.

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

• Warm-up for the Ohio Valley (Missouri, Illinois, Indiana and Kentucky) October 2-4.
• Big storm develops for NW United States October 2-3.
• Stormy and then cold for Colorado October 3-5.
• Line of storms moves through the Midwest October 5-6.
• Warm-up for Colorado October 6-8.
• West Coast storm develops October 10.
• Stormy and then cooler for Colorado October 12.
• Shot of cold air comes in to western United States October 20.
• Shot of cold air moves through Colorado October 19-23.
• BIG shot of cold air comes down from Canada over US/Canada border October 24.
• This brings cold air to Missouri, Illinois, and Indiana (St. Louis, Chicago, Indianapolis) October 25-27.

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.

Warmth Returns to Colorado

As first advertised last Monday, today (Saturday) is the coolest day of the week.  Highs topped out in the 60°s and 70°s across southern Colorado.  Officially, Colorado Springs hit 67° and Pueblo hit 73°.

The cool down will be short lived as temperatures begin to rebound tomorrow as winds turn out of the west and skies turn 100% sunny.  Highs will be in the 70°s and 80°s across the KOAA viewing area.

Mainly sunny skies will prevail for much of the upcoming week.  Forecasters' eyes are looking at a storm that will bring a cold front through Colorado Thursday or Friday.  This front should be a little more potent than yesterday's front.

Right now computer models are a little divided as to when the front passes.  Currently, I'm siding with the front moving through southern and southeastern Colorado Thursday afternoon/evening.  I expect to see falling temperatures Thursday.  Behind the front, there is a chance we could see a little snow, especially in higher elevations.  I think it is entirely possible Colorado Springs could see a little snow early Friday morning.  Stay tuned... - Meteorologist John Dissauer

More Heavy Rain Overnight in Colorado

...Potential for another round of heavy rain overnight...

A Flash Flood Watch continues for counties along the I-25 corridor until 6am MT Friday.

At 10,000 feet above the ground winds are blowing out of the south.  The stream of wind is blowing out of the south at 25-45mph.  The southerly wind is acting as a conveyor belt transporting moisture from New Mexico and north central Mexico and moving it in to southern Colorado.

Water vapor imagery showing moisture located over New Mexico and Mexico.  Green arrows indicate winds at 10,000 feet above sea level.

With ample moisture in place, little waves of energy are moving in to Colorado from an upper-level low pressure system that is located over Nevada/Utah.  The energy is helping to spark off showers and thunderstorms.

Computer models project a couple waves of energy coming to southern Colorado later Thursday evening and again during the early morning hours Friday.  Showers and thunderstorms are expected to develop and move north across the viewing area.

Computer models continue to be bullish on rainfall numbers.  Generally speaking, the models are projecting 1" to 3" of rain for portions of southern and southeastern Colorado through Friday morning.  Some locations, in El Paso County, Pueblo County and Teller County could see 3" to 5" of rain with a few localized amounts 6"+ not out of the question.

Overnight temperatures will only fall off to the 50°s and 60°s.

Friday will see another chance for showers and thunderstorms although, they should not be as heavy as the rain Thursday night/Friday morning.  However, with already saturated ground any additional rain could have flash flooding potential.  High temperatures Friday will be in the 60°s and 70°s.

Chances of rain will continue through the weekend but it appears southern Colorado should begin to dry out early next week.

FRIDAY'S NORMALS:

Colorado Springs:
High: 76°
Low: 49°
Precipitation: 0.04"

Pueblo:
High: 83°
Low: 49°
Precipitation: 0.03"

Time for another look at the experimental looooooong range computer model.  This model takes a look out over the next 762 hours.  To be specific, it is the European Forecast Agency's computer model.

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

• Heat will continue to stay in place over the central United States through September 15.
• Temperatures should be back to normal in Colorado September 17-20
• Heat builds over the western United States September 21-24.
• Temperatures should go below normal for the Midwest September 21-26.  Wouldn't be surprised to see several "waves" of quick moving storms pass through while northwest flow is in place.
• Shot of cooler air and rain moves in through Great Lakes region and Midwest September 22-25.
• Heat builds over the western United States September 29-October 2.
• Hints of a BIG shot of cold air coming down out of Canada for the central United States (and moving through the Midwest) October 4-8.

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.

Tornadoes Below Average in 2013

The Storm Prediction Center has come out with new tornado numbers for 2013 and they indicate that the number of tornadoes are below normal this year.

Through August 20, 2013 the SPC has recoreded 610 tornadoes.  That is only 62% of the twelve year annual average, 984.  We should see a ramp up of severe weather in the next three months but enough to make up the 374 deficit?  Not likely.

Although the numbers are low for this year, this isn't the lowest we've seen through August.  According to SPC, in 2002 there were only 579 tornadoes through late August.

Notice in the graph above there were increased periods of tornadoes in 2003 and 2004 and again 2008 through 2011.

This is an interesting trend as 2012 was also well below normal.  Severe weather statistics do go through cycles.  If we can get a few tropical systems coming on land, these numbers could quickly jump.

Wet Week Ahead for Colorado

...Cool temperatures and heavy rain headlines the weather today and much of the upcoming week...

An upper-level low has established itself over the western United States.  Ahead of the low, southwesterly winds are helping draw up monsoon moisture from the south.  The moisture has moved over southern Colorado and will allow for periods of showers and thunderstorms.

Tonight we'll have cloudy skies with scattered showers and thunderstorms.  Computer models are indicating an up-tick in moisture around sunrise tomorrow.  Lows will be in the middle 50°s to lower 60°s.

Expect to see cloudy/overcast skies Wednesday with periods of showers and thunderstorms.  At times, the rain could be heavy.  We'll have to keep an eye on some of the area burn scars.  Highs will be in the upper 60°s to upper 70°s.

Computer models suggest rain will continue through Sunday for most of southern Colorado.  Some of the rainfall projections from the computer models are staggering.  A three-computer model average suggests 1,925% the normal rain for Colorado Springs and 3,000% the normal rain for Pueblo through 6pm Friday.  Looking further out, a two-computer model average suggests 2" to 4" of rain for parts of the area Wednesday through next Tuesday morning.  - Meteorologist John Dissauer

NORMAL'S FOR WEDNESDAY:

Colorado Springs:
High: 77°
Low: 49°
Precipitation: 0.05"

Pueblo:
High: 84°
Low: 50°
Precipitation: 0.02"

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"