Tuesday, March 24, 2015

First Round of Severe Weather

Over the next 36-48 hours, parts of Region 8 will see their first round of severe weather of the year. Make sure you have a way to get warnings! The best way is to text STORM to 52488. Then, enter your county.

The severe weather threat map has not changed from the one we sent out on social media yesterday. At KAIT, we still think there is a medium risk of severe weather in NW Arkansas and parts of Missouri for later today:
The latest short-term data suggest that we will see storms develop around Joplin, MO around 4:00 or so:
This is when the air will be at it's most unstable point. We have talked about CAPE in the past. It's the amount of energy available for the storms. The higher the number, the more energy there is available. Other factors come into play for the storms to develop, but this is just how much "fuel" is there for them. Notice the plume of energy ahead of the storm:
 By the early evening 6:00-7:00, the line becomes more mature:
I think we will see some warnings in our NW counties this evening. At this point, the air is still pretty unstable. Notice that the storms are running ahead of the most unstable air....
By 10:00, we have storms coming into Region 8, but they should be weakening:
Stay informed later today and again tomorrow night. We will be watching the storms closely.


Wednesday, March 04, 2015

Bad Winter Storm Starts Today!

I don't think I'm overselling this one. There is a lot of moisture with this storm AFTER we go below 32°. Here are the bullet points as of 7:00 AM on Wednesday:

  • This morning is mainly WET. 
  • I say "mainly" because the freezing line will come into Southern MO and extreme Northern AR before lunch.
  • This winter storm will be worse than the one 2 weeks ago.
  • There will be snow on top of the sleet this time around.
  • I expect the roads to be very bad tomorrow morning, despite the hard work of the highway department. This will be a hard storm to beat.
  • I typically don't talk about schools being closed or open, but I will say that schools will be impacted on Thursday and Friday.
  • Generally speaking, 5-8" of a sleet and snow combination is expected.
OK, let's talk about timing. The freezing line is moving south and the Storm Prediction Center has already highlighted our area for big problems later today. In case you did not know, the SPC watches winter storm, too:
Here's what the latest short-term data is showing and it looks to have a good grasp on the situation. Let's fast-forward to 2:00, when many parts of Region 8 will be switching to freezing rain and sleet:
Once the freezing line starts moving in, it keeps heading south at a good pace, switching everyone to a Winter Storm Mode. Here's 4:00 PM:
By 8:00 PM, everyone is below freezing and we are in the middle of a Winter Storm and some will be switching to snow:

This looks like a bad winter storm. Finish up any errands you need to run this morning and hang out at the house tonight. Some of you may have to stay in the house for a couple of days.

Take care,

Monday, March 02, 2015

PANICOMETER for Wednesday

While we are still trying to get a better grasp of the type of precipitation and amounts, the IMPACTS on Wednesday will be the same if this storm continues its track. Whether it is 6" of snow or 2" of sleet, the impacts will be high enough to keep some people at home for a couple of days. As of now, the coveted PANICOMETER sits between "Get Milk and Bread" and "Grab the Sled". No need to Panic, yet. ;) I do think this storm will impact us a little greater than the one that hit 2 weeks ago. If you missed my previous posts on the specifics of this storm CLICK HERE.

Stay up-to-date on any changes! Andrew will have your forecast at 5:00, 6:00, and 10:00. I'll be back to work tomorrow.

I may try to do a video update later tonight.

Take care,

Another SLEET Storm?

This storm is going to keep us on our toes this week. At this point, the predominant precipitation TYPE could be SLEET again. Remember, sleet is little pellets of ice.

Things we have learned about sleet in Region 8:

  • It does not accumulate as fast as snow in regards to depth. The ratio between snow and rain is roughly 10:1, meaning, 1" of rain equals 10" of snow. Sleet is typically a 3:1 ratio. Meaning 1" of rain is about 3" of sleet. This is why you should not get excited when people post images of Jonesboro getting 14" of snow. Sleet would make that number much lower.
  • Sleet weighs a lot. While it may not add up as fast, sleet still weighs the same because it has the same liquid content. So, 10" of snow weighs the same as 3" of sleet on a roof!
  • Sleet sticks around longer. It's harder to melt and seems to linger around forever. That's why we still have sleet on the ground from 15 days ago.
So, why are we thinking a lot of the precipitation will be sleet AGAIN in Region 8? Let's take a snapshot of the atmosphere on Wednesday evening from this computer model. The bottom of the image is the ground. The top of the image is high in the sky. The red line is the temperature and the green line is the dewpoint. You measure the temperature from the numbers at the bottom and their coordinating lines. I have made the "0° Celsius" line in light blue to help you out:
If you notice, there is a warm layer between 5,400'-11,000' on Wednesday evening. This is where the snowflakes will met into droplets. They will refreeze into ice pellets (sleet) before making it to the ground to ruin the rest of our week.

Radar may look something like this on Wednesday evening. Some getting snow... but, most of us getting sleet:
The bottom part of the atmosphere is just not good at making snowflakes. The bottom part of the atmosphere is lazy and only creates sleet. :) So... we may end up with another sleet storm.

Let's hope something changes. All snow would be a headache because it adds up faster... so I'm cheering for all rain, which will probably lose.


Winter Storm May Impact School AGAIN

A WINTER STORM WATCH has been issued for most of Region 8 for Wednesday. Here are my thoughts as of Monday at 8:00 am:
  • Plain Rain FIRST on Tuesday, with highs near 60.
  • Changeover to SLEET Tuesday night into Wednesday. (1-2” of sleet)
  • Changeover to SNOW on Wednesday at some point. (1-3” of snow on top of the sleet)
  • This can change and not all data is in agreement on TIMING.
  • There’s about a 12-15 hour variance on the timing right now, but the end result is nearly the same.
  • I do not expect many power problems as we should not see much freezing rain... just briefly in transition.
  • I expect schools to close. Depending on timing, either leaving early on Wednesday or not going at all. I doubt there will be school on Thursday and Friday as it lingers in the cold air.
This can change and we will update everyone as new data arrives.

Have a good Monday,

Sunday, March 01, 2015

More Wintry Weather This Week?

I wish I did a better job of NOT looking at data on my day off. In my profession, having a true "day off" is almost impossible though. As I look at the forecast data coming in this morning, I'm concerned that parts of the state will have more wintry weather on Wednesday. This is very concerning because the kids do not need to miss any more school and there are basketball tournaments. Here are my thoughts at 11:30 am on Sunday:
  • First, we are still 48-72 hours away from any problems
  • A lot can change in the forecast in 3 days.
  • Tuesday looks warm with showers and thunderstorms
  • Cold air arrives Wednesday and moisture overrides the cold air coming in...
  • Parts of Region 8 will likely see some wintry weather on Wednesday.
  • WHERE and HOW MUCH are still in question.
  • Precipitation TYPE is still in question.
Models are not in great agreement yet. Some data suggests that the rain will be gone and south before the cold air arrives. That would be "best case scenario". Other data suggests sleet and some suggests that the entire column of the atmosphere will be below 32° and it will be plain ole snow. At this point, we will say a "wintry mix" until we can get more specific.

I am announcing some of the 5A basketball tournament at Greene County Tech this week. I have already been talking with the organizers of the tournament and we are going to stay in close contact all week. That tournament impacts a lot of Region 8 schools. I'll keep you posted. Let's hope everything stays on schedule.

Take care,

Wednesday, February 25, 2015

Snow Stays South and BYOCA

It's always concerning when a storm that is expected to drop up to a half-foot of snow is this close to Region 8. I never get a good night's sleep in this type of situation. I went to bed late and was up at 5:00 am. Now that the storm is unfolding, it appears that most (if not all) of the storm will miss Region 8. We still have a Winter Weather Advisory in effect for our southern most counties of Region 8, just in case. Here are the bullet points:

  • Travel through a large part of Central and Southern Arkansas will be bad this afternoon.
  • Travel through northern Mississippi will be bad later today.
  • Travel through northern Alabama will be bad later today.
  • Region 8 will only see flurries or sprinkles it appears.
  • Some of Region 8 may even go into the 40s.
  • It will be colder near the snowfall due to dynamic cooling of the storm itself. In simple terms, the storm is bringing it's own cold air to the party from aloft and transporting it to the surface.
Here's what we are expecting at Noon:

Here's what we are expecting when the kids get out of school:
Here's what we are expecting at 6:00 PM:
Once this storm is done, the total snowfall accumulation could look something like this:
For someone that is not a big fan of winter, I like this. In addition to missing the snow completely, I mentioned that we could be in the 40s today. Near the storm, the changes in pressure vertically will help transport colder air to the surface. We call this dynamic cooling. I like to say that this is a storm that is "bringing it's own cold air" to the party or BYOCA. :) Because of this, it sometimes looks like a "hole" of cold air on a temperature map. Short-term high resolution model data suggest we could get well into the 40s today, with low to mid 30s in the snow. Can you spot the storm?
Have a great day and enjoy missing the snow!