Thursday, November 11, 2010: Thoughts on the upcoming winter - winter storm rating scale

January 19, 2011:

Winter Forecast Update:

Cold weather to continue.  We abondoned the milder than usual thoughts back at the end of December and early January.

That appears to have been a good call - cold weather has continued and will continue into the coming weeks.

February - looks to start off cold.

This winter has ended up quite unusual - cold for nearly the last 2 months!

Total reverse in January from what was actually forecast and expected.  This is why I always say that long range forecasts are extremely difficult and should be taken with a grain of salt.

Just nearly impossible to nail forecasts that far out.

This winter has proven that to be the case.

-  Beau

January 1, 2011:

UPDATE

Abandoning any idea of above normal temperature averages for January.  Appears the cold pattern will continue.  December forecast went well.  We may see some moderation as we move towards the end of January - that has been the forecast for awhile and that is what I told the Paducah Sun for their article. 

January will likely end up below normal in the temperature department. I still believe and I am forecasting that we will ride the warm/cold boundary for January and February.  We have just been on the cold side more than the warm side - so far this winter.

Memorable snow events are likely along this boundary - ice events, as well. No forecast changes otherwise - an active winter is ahead of us. That includes the severe weather risk when we are on the warm side of the boundary.

Will have to re-evaluate February as we draw closer to that time period.

For now - January appears to be heading towards some serious cold waves.  With some moderation later in the month.  Will see how it goes.

Several light snowfall events are very likely this month - in the 1-3" range. 



November 11, 2010:

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My thoughts on winter can be found below.  I am in agreement - for the most part - with the local National Weather Service Office out of Paducah, Kentucky on how the winter is expected to unfold.  Obviously nobody is forecasting specific events for the upcoming winter.  The best that all of us can do is give generalities and pattern forecasts.  A lot of the forecast information is based on probabilities.  That means a better chance of one type of pattern vs another type of pattern.

Please view the official NWS forecast, as well.  I have linked that information below.  We have a great National Weather Service Office in Paducah - be sure and utilize all of their products and information.

You can find more updates on my Facebook (under Beau Dodson) - Twitter, as well

We want to thank all of our veterans today for their service to the United States!  Thank you for protecting our lives! I am proud of all of my family members who have served this great country!  My Great Uncle Robert Dodson who was a weatherman war hero!  Read more about him on this site - click here.  To this day the Dodson Award continues to be given out to meteorologists around the country.  Click here.  Or click the image below to read more about the Air Force Dodson Award. 

























Bottom line it for me Beau...

For southern Illinois and far western Kentucky...

Severe or extreme weather risk for today, tonight, and tomorrow:  0%

Fire risk/danger will be quite high today.  Please don't burn brush or leaves. 


Today - Sun and clouds.  High near 77-80 degrees.  Southeast winds 5-10 mph.

Tonight - A few clouds tonight.  Cool.  Low near 45 degrees.  South winds 5-10 mph.

Tomorrow - Partly Sunny - a few clouds.  Mild.  High temperature around 75 degrees.  South winds 5-10 mph.

Your seven day forecast from the NWS can be viewed here - click here.

Barometer reading this morning is in the 30.20-30.40" range.  Last 24 hours of data - click here. 

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Today's weather map:





















Our best rain chances arrive on Friday night (very late) and most likely on Saturday.  Rainfall totals of 0.00-0.25" appear to be the best forecast, at this time.  Some areas may miss the rain.  This is not an impressive event.  Unfortunately.

Here is what the GFS (one model) is showing on Saturday.  The blue/purple/pink areas would be rainfall.  At 18z - Saturday afternoon - the rain is or has been moving over our local counties.  Again, some locations may not receiving hardly any rainfall.





















Sunday should be dry - an increase in shower chances will be possible Sunday night - mainly to our south and east.  I will touch more on that during the Friday update.

Here is what the GFS is showing on Sunday night/Monday.  This is the system moving in from the south.  Areas to our south and east will have the best chances for rain.  Let's hope the storm is a bit further north than forecast.  We desperately need the rain.  Right now it appears the storm will be too far south to help our drought conditions.

Colder air in the extended - still appears to be on track.







































Winter weather preparedness week is right around the corner!  The Paducah, Kentucky NWS has posted the following information.  Click here.  For more on winter weather safety - click here.

Let's take a look at the upcoming winter.  I have been touching on the subject since September.  There have been several lengthy posts - the most thorough post can be found here.

The official NOAA Winter Weather Forecast can be read here.

I will be working closely, as a team, with the NWS Office in Paducah, WPSD, KFVS, WSIL, other local and national meteorologists, forecasters, and emergency management teams to make this the safest winter possible.  Every forecast won't be spot on - winter is a difficult and stressful time to forecast.  We might not always agree 100% on a forecast (and there is nothing wrong with that - every meteorologist and forecaster has their own opinion on how a storm system might unfold). But, we will give it our best efforts - time and energy.  

Remember to check back often on all of the above sites, television stations, radio stations, print media, Facebook, and Twitter for the most up to date weather information.

If you don't have a NOAA Weather Radio then now is the time to purchase one.  24/7 weather - local forecasts - watches - warnings - advisories - current conditions for our local area - extended outlooks and much much more.

Most of the local television meteorologists have Facebook pages - I would suggest adding them as friends.  None of us can always be here - but all of us together, as a team, can provide you with the best coverage possible.

If you are not a member of my email list then please email me at beaudodson@usawx.com   I will add you to the list.  I usually only send out emails when there are significant storm systems threatening our region (or when I have a seasonal forecast).

My thoughts on winter 2010-2011

It appears that we will have a front loaded winter - that means that the coldest averages may arrive from the end of November through the first week of January.  That is not to say that we won't have cold weather after that time period.  We absolutely will.  It simply means that I am expecting temperatures to average above normal from early January into February.  Below normal temperatures are once again likely as we move into March and April.  The potential exists for a late freeze and frost during the spring months.

The winter will likely be volatile and full of dramatic swings.  This type of pattern is not uncommon for our region. 

Keep in mind that it only takes one big snow or ice event for the public to perceive the winter as being "severe, extreme, or bad."  Just because we may experience above normal temperatures, for part of the winter, does not mean we won't see extreme swings.  I am not a huge fan of long range outlooks.  Mainly because there is so much variability in our regions weather.  Trying to summarize an entire winter is nearly impossible.  However, I do enjoy the challenge.

Also, above normal temperatures don't always equate to a mild winter.  Keep that in mind when glancing over the NWS forecasts and their maps.  Their maps are probability maps.  That means that warmer than normal simply means just that - warmer than the averages.  If the averages are cold and you are slightly above normal - it is still cold.

I would not be surprised to see the primary storm track north of our region this winter - thus putting us in the  battle ground for severe weather potential.  A storm track to our north would provide areas from Kansas into Iowa and northern Illinois/Wisconsin/Michigan with plenty of snow and ice.  I would expect our region to have frequent swings from above normal temperatures to below normal temperatures.  The proverbial battleground could be quite common across our region.  This would be unlike last winter when we saw mostly below normal temperatures and consistent/persistent cold.

I have also stated that I believe the risk for a significant ice storm (1"+ of freezing rain) will be above normal from Oklahoma, eastern Kansas, southwest/central/northern Arkansas, Missouri, southern Iowa, Illinois, Indiana, northern Mississippi, Northern Alabama, Northern Georgia, Tennessee, Kentucky, and southern Ohio - a corridor along those lines.  See the map below - perhaps areas a bit further southwest and south of where I have drawn the line, as well.

Remember that saying the odds will be above normal for ice does not mean we will have a big ice storm.  It simply means that the pattern could favor ice.  There are conflicting views on how La Nina patterns influence the probabilities of ice events. 


















In any given year the risk for a significant ice storm is about 1-5% (depending on your location in the area mentioned above).  As stated above it is impossible to predict exact/specific events months in advance.  It is only possible to forecast patterns.  In a normal year our region experiences some freezing rain - 1 or 2 episodes.  Normally accumulating less than 0.25".

If La Nina ends up being one of the primary weather influences this winter then a strong and active northern jet is likely.  Lot of storm systems - lot of cold fronts - quite a bit of active weather.  The question will come down to where the battle lines set up between the warm and cold.  Seems like that is usually the case in this region.

The map below shows the differences in our weather when La Nina is weak vs strong.  This years La Nina is quite strong.


















Is also appears that the NAO has a better chance of being neutral to slightly negative this winter.  This has been the trend for awhile. 

In layman terms:

Above normal temperatures appear likely for our region during at least part of the winter.  A cold December - followed by above normal temperatures in January and February - followed by below normal temperatures in late February or March and April.  A late frost/freeze will be possible during the spring.

Above normal precipitation - especially January through March.  The maximum area for above normal precipitation will likely run from Missouri into central Illinois and into Indiana, Ohio, southern Michigan and into New York and Pennsylvania.  Frequent/strong low pressure systems passing to our north (this would keep us in the battle zone for rain, snow, and ice).  There is the potential for one or more severe weather episodes with tornadoes possible.  Also there are some indications that the middle or late March period into early to middle May could bring below normal precipitation - but this is a bit more uncertain than some of the other indicators above.

Several southern track storms - coming out of the Gulf of Mexico and moving through the southlands.  This will provide chances for snow and mixed precipitation to our region.  Signals are there for some fairly deep low pressure areas this winter.  

Several significant cold waves where temperatures fall below 10 degrees - but transient in nature.  We will likely see some impressive temperature swings with a pattern that appears to be unfolding.  Impressive meaning temperatures dropping from the 50s or 60s into the teens and 20s after frontal passage.

That would mean a winter of extremes (which seems to be the pattern for the past decade) - wild temperature swings.  From milder air to colder air - strong cold fronts - deep storms in the central United States.

There are also a number of signals that are pointing towards much below normal temperatures, for the Alaska months, over Alaska and western Canada, northwest United States into the northern Rockies.  Some of that bitter cold air is likely to spill into the Great Lakes and central parts of the United States during the winter months - which in itself isn't unusual - but what might be unusual is just how cold some of those temperatures spilling in from the northwest might be.  Something for us to watch.

I will be using the ice storm rating scale again this year.  You can read more about that scale by clicking here.

And to better convey the threat level for each winter storm - (click here for full details)  I have made a winter storm category scale.  The Dodson Snowstorm Scale will run from category 1 through category 5.  Category 5 being a near historic or historic event.  I have also included a quick summary of the hazards for each of the threat levels.  This is an easy way to quickly convey the magnitude and impact of a winter storm.  Impact is what you care about.

As always, remember that any winter storm can be dangerous.  Slick roadways can cause problems whether there is 1/2" of snow or 10" of snow.  Always use caution when driving on slick roads.









Dodson Snowstorm Rating System 

Category 1 Snowstorm


Accumulation:  Snowfall accumulations of 1-4” are forecast.  A fairly common event.
Life Threat Level:
  Low threat to life if residents use care and caution when venturing out.  Remember that any roadway that is slick can be dangerous.  Nearly 1000 people were killed during the last two winters from accidents on slick roadways.
Travel Impact:
  Roads may become slick.  Use caution.
Economic Impact:
  Little to low economic impact is expected.
Advice to Emergency Officials:
  Expect normal snow related operations.  Listen for updates from the NWS and local media.

Category 2 Snowstorm


Accumulation:  Snowfall accumulations of 4-8” are forecast.
Life Threat Level:  Some threat to life if caught out in the storm without an emergency kit or proper supplies.  Use caution if you must travel.  Elderly residents should use caution.  Residents with heart conditions should use care if they must remove snow from sidewalks or driveways. 
Travel Impact:  Roads will likely be slick and hazardous.  Some difficulty for light weight and small vehicles – especially with snowfall totals of six inches or greater.  Caution is advised.  High winds can cause blowing and drifting of snow - especially in rural areas.
Economic Impact:  Low economic impact. 
Advice to Emergency Officials:  Extra staff may be necessary during the peak of the event.  Otherwise normal snow related operations are to be expected.  As always, listen to NOAA Weather Radio and local media for updates.

Category 3 Snowstorm


Accumulation:  Snowfall accumulations of 8-12” are forecast.
Life Threat Level:  Some threat to life if caught out in the storm without an emergency kit or proper supplies. Travel is not recommended during peak of storm unless an emergency or roadways are plowed.  Elderly residents should use caution.  Residents with heart conditions should use extreme caution.  A few tree branches and power lines may break if the snow is wet.  Significant threat to livestock and other outdoor pets/animals.
Travel Impact:  Travel is not recommended until roadways have been plowed.  Until the snow is removed there will be significant travel difficulty for light weight and small to medium sized vehicles.  Moderate to high winds will cause considerable blowing and drifting snow.
Economic Impact:  Moderate economic impact.  Some businesses will likely close for short periods of time. 
Advice to Emergency Officials:  Extra staff will likely be needed during the peak of the storm.  Towns and cities may have significant piles of snow that will need to be removed.  This is especially true of events with greater than 10 inches of snow.  As always, listen to NOAA Weather Radio and local media for updates.

Category 4 Snowstorm


Accumulation:  Snowfall accumulations of 12-16” are forecast.  A rare and unusual event. 
Life Threat Level:  Snowstorm poses a substantial threat to life.  Those who venture out in vehicles can expect extreme difficulty.  Elderly residents should stay indoors.  Residents with heart conditions should use extreme caution.  A few structures with large roof spans may collapse under the weight of the snow - especially if heavy sleet or heavy wet snow occurs.  Some tree branches, trees, and power lines may break if the snow is wet.  Power outages possible if the snow is wet.  Significant threat to livestock and other outdoor pets/animals.
Travel Impact:  Travel is not advised.  Some road closures will be possible.  Interstates and highways may be closed in some areas.  For most vehicles and trucks, travel will be nearly impossible, until roadways are plowed.  Towns and cities should expect travelers to be stranded.  Some motorists may attempt to abandon their vehicles.  Airport delays and/or closures will be possible. Towns and cities will likely require major snow removal operations – including the use of dump trucks to haul away snow.  Anyone who absolutely must travel should notify friends and family of their travel plans.  Carry a cell phone at all times.  Moderate to high winds could cause significant blowing and drifting snow. 
Economic Impact:  Significant or major economic impact.  Many businesses, malls, large colleges, and government agencies will be closed for one or more days.  Hotels may quickly fill up with stranded travelers.  Some counties may need sheltering operations.
Advice to Emergency Officials:  Extra staffing of all operations will likely be necessary.  Emergency officials are urged to talk to their local media before the storm hits – advising residents to prepare for a significant winter storm event.  A local state of emergency declaration may be required in some counties, towns, and cities.  Emergency personnel may need to plan on spending the night at facilities or may find themselves stranded at their place of employment.  Four-wheel drive transportation may be necessary for essential personnel workers.  As always, listen to NOAA Weather Radio and local media for updates.

Category 5 Snowstorm


Accumulation:  Snowfall accumulations of 16” or greater are forecast.  Historic or near historic event.
Life Threat Level:  Serious/significant threat to life and property.  Extreme caution is urged – travel will be nearly impossible.  Elderly residents should stay indoors.  Residents with heart conditions should use extreme caution.   Anyone venturing outside should notify friends and family of their plans.  Carry a cell phone.  Some structures will large roof spans may collapse under the weight of the snow - especially if heavy sleet or heavy wet snow occurs.  Numerous tree branches, trees, and power lines may break if the snow is wet.  Power outages will occur if the snow is wet.  Extreme threat to livestock and other outdoor pets/animals.
Travel Impact:  Travel is not recommended and will be nearly impossible until the snow is removed from roadways.  Numerous road closures will likely occur.  Interstates and highways may be closed.  Cars may be abandoned on interstates and other roadways.  Travel will be nearly impossible for vehicles and trucks.  Airport delays and/or closures will likely occur.  Towns and cities will require major snow removal operations – including the use of dump trucks to haul away snow.  Anyone who absolutely must travel should notify friends and family of their travel plans.  Carry a cell phone at all times.  Moderate to high winds could cause significant blowing and drifting snow.
Economic Impact:  Major to extreme economic impact.  Many businesses, large colleges/universities, and government agencies will be closed for several days.  Many or all school districts will be closed for several days.  Hotels may quickly fill up with stranded travelers.  Some counties may need sheltering operations.  A local state of emergency declaration may be required in some counties, towns, and cities.

Advice to Emergency Officials:  Extra staffing of all operations will be almost certain.  Emergency officials are urged to talk to their local media before the storm hits – advising residents to prepare for a significant to extreme/historic winter storm event.  Emergency personnel may need to plan on spending the night at facilities or may find themselves stranded at their place of employment.  Four-wheel drive transportation may be necessary for essential personnel workers.  National Guard units or large four-wheel drive vehicles may be necessary to help local emergency officials respond to emergency calls.  Shelters may be necessary to house stranded motorists.  As always, listen to NOAA Weather Radio and local media for updates.

* Keep in mind that schools in this region have been known to close before snow even begins to fall.  So, I did not include any guidance for the potential of school closings (other than large colleges and universities).

** High winds during any of the above categories could cause any given forecast to produce more adverse impacts than the category states.  Each individual event will need to be evaluated - it is possible than an event could be upgraded because of sustained high winds causing blowing and drifting snow.

For more information on Illinois winter storms please visit the Illinois State Water Survey web-site


Confidence in the Forecast?








I will also be using a confidence meter during the upcoming winter storm season.  This is modeled after the Capital Weather confidence meter.  I added the probability numbers to better express the meaning of low, medium, high, and very high.  You will find this meter mentioned in my emails or on my weather analysis blog posting.  My daily analysis can be found by clicking here.

- Meteorologist Beau Dodson
McCracken County Office of Emergency Management

For the latest watches and warnings please visit your local National Weather Service Office http://www.weather.gov/organization.php

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