Not Out of the Woods Yet

Wow!  Yesterday was just a colossal tornado outbreak.  It was one of those few times when everything came together to produce a large tornado outbreak.  In the end we got something like this:

My forecast certainly busted.  I don't think a lot of people anticipated the storms to initiate as early as they did.  If you look at the SPC's forecast, you'll notice that they kept expanding the high risk westward.  Unfortunately for me I didn't get a chance to update my forecast, so I ended up having my high risk area too far east.  While the Great Plains might be done with their activity for now, the US isn't out of the woods yet, as another dangerous day looks to be taking shape today, particularly across Western Wisconsin this afternoon and evening.  The SPC issued a Moderate risk today:

General

Tornado

Hail

Wind

What we have today is the low pressure system from last night moving northward.  As it does so there will be marginal instability developing across the moderate risk region.  That's one of the differences between today and yesterday.  Yesterday there was more instability to work with than today.  However, today has absolutely ridiculous wind fields, unlike yesterday.  The winds are so strong aloft that I would almost say that a storm would have severe winds as soon as it develops.  Add in the low level jet that will really ramp up tonight, we could be dealing with a squall line that stretches from Wisconsin down to the Gulf Coast.  Now there is little to no cap so storms should have no trouble developing into a line of severe thunderstorms this afternoon.  If a storm can remain semi-discrete, it may be able to produce a brief tornado given the ridiculous speed shear in the upper levels of the atmosphere.  This would be most likely in the Moderate risk area.  Taking this and a little bit more into account I got this:

Stay tuned!

Major Tornado Outbreak Today

Category: Severe Thunderstorms
Post Type: Quick Outlook
Urgency: PDS


I don't have much time this morning.  Basically, my coverage will be limited for today, as I will be out somewhere for most of midday, and then I will be at Fermilab starting at 6 pm tonight.  So it is gonna be tough to get much info out.  Here is my map for today:

Very dangerous day today.  Stay tuned!

VERY LARGE SEVERE THUNDERSTORM RISK TOMORROW!!!!!!!!!!!!!!!!!

Category: Severe Thunderstorms

Post type: Outlook/Warning Message

Urgency: PDS

Tomorrow has potential to be a very big day when it comes to severe weather.  For the first time in six years, the SPC issued a High Risk of severe thunderstorms the day before the event was supposed to happen.  Here is the map:

IF YOU LIVE IN THE RED OVAL, YOU NEED TO PREPARE!!!!!!  MAKE SURE THAT YOU HAVE A DISASTER KIT PUT TOGETHER FOR TOMORROW.  ALSO MAKE SURE THAT YOUR NOAA WEATHER RADIO IS PLUGGED IN AND HAS NEW BATTERIES INSIDE -- YOU NEVER KNOW WHEN THE POWER WILL GO OUT.  IF YOU DON'T HAVE ONE, YOU NEED TO GET ONE IN ORDER TO PROTECT LIFE AND PROPERTY.  MONITOR FORECASTS FROM THE STORM PREDICTION CENTER AND YOUR LOCAL NATIONAL WEATHER SERVICE OFFICE AND STAY ALERT!!!!!!

Quick Update on Severe Potential

Category: Severe Thunderstorms
Post Type: Update
Urgency: Take Action


Hi guys!  We have a very dangerous situation ongoing in the Southern Plains currently.  There are multiple supercell storms moving through the region.  One of them is indeed tornado warned.  These storms have produced damage, and should continue to do so.  Let's get started.  The Storm Prediction Center (SPC) went against mine and many others' thinking and decided not to issue a moderate risk for severe thunderstorms, even though it appeared as though something like what is going now was going to develop.  We currently have two watches, one tornado and one severe thunderstorm:

Tornado Watch

Severe Thunderstorm Watch

The combination of high instability and medium wind shear should allow for storms to sustain themselves as severe multicell/embedded supercell thunderstorms.  Each storm that develops will have all of the tools necessary to become severe as storms are very spread out at this time.  Any storms that get strong enough to generate their own wind fields will definitely need to be watched.  Anvil level winds are actually pretty strong, so some storms that can become isolated could definitely develop some classic supercell characteristics.  As the low level jet ramps up this evening look for the tornado threat to increase some.  Definitely stay tuned, folks!

Severe Weather Outlook for April 13, 2012

We yet again have a severe threat to deal with today.  Its really been a rough week for the Plains, with a lot of slight risks being issued.  I am sorry for my absence yesterday, I was on an all day field trip.  Anyway, back to severe weather.  The Storm Prediction Center (SPC) has issued a slight risk for severe thunderstorms:

General Outlook

Tornado Outlook

Hail Outlook

Wind Outlook

With a glance at those maps, I know that this is already looking like the most likely day for an upgrade to a moderate risk so far this week.  It appears that the SPC is really hitting it up on the hail threat for this afternoon.  After glancing at the models for this afternoon, it appears definite to me that there is a threat for supercells and tornados with tonight's event.  First of all, instability is sufficient to produce severe thunderstorms.  Also, there is plentiful shear for storms to really get going.  Another thing that I looked at is the fact that LCL heights are much lower to the ground than previous events this week have had.  LCL, or Lifted Condensation Level is basically where the temperature equals the dewpoint first.  It is a good indicator for how high the cloud base will be.  Today, LCLs are relatively low, so we can expect a couple of tornados across the risk area, particularly in Oklahoma.  Also, anvil level winds support High Precipitation to Classic supercells, with the latter being the most likely to produce a tornado, particularly strong ones.  Taking all of this into account, I got this:

I decided not to issue a moderate risk quite yet due to some uncertainty as to exactly what the main forcing is.  Also, the SPC has not issued a moderate risk yet, so I decided to just play it safe.  Please note however that this is a high end slight risk, and strong tornados are possible today.  If the situation warrants, I may upgrade this to a moderate in a *possible* update this afternoon.  For now, stay tuned!

Severe Weather Outlook for 04/11/2012

A slight risk of severe weather has been issued by the Storm Prediction Center (SPC) for today, April 11, 2012.  Here are the images:

General Threat

Wind Probabilities

Hail Probabilities

Tornado Probabilities 

As you can see, the SPC is aiming for a bulls eye in the Texas and Oklahoma Panhandle regions right now.  This comes as a convergence zone tries to develop in the Plains.  The main limiting factor for this severe weather event is the fact that moisture is actually limited today.  This really drags instability and thus the overall threat downward for today.  There is actually enough shear and dynamics to potentially push a few a few supercells into developing, however, I am not seeing a widespread threat with this.  However, if we can get a lone supercell to show itself, and it just happens to be in the zone of maximum shearing, we could get something going.  As nightfall comes, we should get a cluster or two of storms to develop bringing with it the always present threat of damaging winds.  So taking this all into account, I get this:

Stay tuned!

Moderate Risk of Severe Weather Today

Today we find a Moderate Risk of severe thunderstorms issued by the Storm Prediction Center (SPC) in the southern plains:

This comes as a dry line marches across the region.  According to the NAM computer model, a dry line bulge will develop in the threat area.  A dry line bulge is area where severe weather is typically enhanced, with tornadoes being most likely in storms along the bulge:

I drew it in with a black marker above.  NAM simulated reflectivity is indicating that there will be a few storms along the dry line, with the worse of them sitting up at the dry line bulge.  Taking these and a few other factors into account, I produced this map:

I did include a larger risk area than the SPC did mainly due to the fact that the NAM is indicating that storms may fire farther south than the current risk area indicates.  For more information from the SPC, click here.  Stay tuned!

Major Severe Weather Outbreak Possible Monday

Category: Severe Thunderstorms
Post type: Outlook
Urgency: Tranquil, for now


The SPC has outlooked a very large area of severe thunderstorms across the south for Monday, April 2nd:

Inside the purple coloring is where the SPC expects a greater than 30% chance of severe thunderstorms to develop.  However, when you get an area that large, one can usually expect there to be a concentration of higher probabilities embedded somewhere in the outlook area.  And keep in mind, that map only shows the 30% risk of severe thunderstorms.  There is a slightly lesser risk of severe thunderstorms that runs all the way up into Wisconsin.  Please keep your eyes on this event, as it has the potential to affect lives and property.  Stay tuned!

Lots of Rain for the Next Five Days, plus some Severe Weather!

Portions of the Midwest/Ohio Valley are going to be seeing a lot of rain in the next five days, mainly the result of the current rain storm spreading across the country.  Here is the expected rain total for the next five days:

We can see that the most rain should fall across Tennessee.  Here is the current radar loop:

We can also see a slight risk of severe thunderstorms across the Mississippi River Delta region.  More information can be found by clicking here, leading to the SPC website.  Stay tuned!

Severe Weather Possible Today

Just wanted to show you the SPC's maps.  No time for a discussion this morning.  I will not be back until later this afternoon than usual.  Here they are:

Categorical Outlook

Wind Outlook

Hail Outlook

Tornado Outlook

Stay tuned!

Severe Weather Early Next Week?

Today, we found this map from the SPC:

It shows potential for severe weather on Monday, November 21st.  This would be a pretty late time in the year for a severe weather outbreak.  So while instability isn't that strong, shear is very strong so any storms that develop could easily go tornado.  Just something to think about.  If we continue to see a threat, we will update you in the future.  Stay tuned!

Severe Weather Update

It's been a while since we have had severe weather to worry about, but today we're getting it.  Currently there are multiple tornado watches in effect.  Here I have a sort of "uber-map" from the SPC.  It shows the current radar, current watches, and the convective outlook:

This should update as time progresses, so check up here to see how the storm is progressing.  Here are the storm reports as of now:

We see some spotty reports, but as the line of storms on radar intensifies, we should see more reports.

In the above image we can see that the storms are associated with a long cold front.  Ok that's all I have for now, can't go into too much detail.  Stay tuned!

Severe Weather Outlook

Today is a slight risk day from the SPC, as a cold front sweeps across the nation.  Here is the latest suite of maps from the SPC this morning:

Categorical risk

Tornado threat

Wind threat

Hail threat

While the threat is definitely not as great as yesterday, look out for a couple of tornadoes and especially a few reports of wind damage, as winds are strengthening aloft.  It won't take a very strong shower/storm to tap in to these and produce a wind damage threat.  We won't be issuing a map this morning, as there isn't enough time.  If we have time this afternoon, one may come out.  Stay tuned!

Severe Weather Outbreak Concerns Early Next Week

Concerns are growing for a possible severe weather outbreak next week.  And if not next week, some time in before the month is over.  The atmosphere is primed for winter, as we'll discuss later, but before winter comes, we have to get this warmth out of the way.  This should result in at least a small outbreak before November is over.  Right now, we are starting to pin down that time.  Here is the SPC's 4-8 day outlook:

We can see that the Storm Prediction Center believes that the worst of the severe weather will occur in Oklahoma/Texas on Day 5, followed by another risk in the ArkLaTex region on Day 6.  Here is my preliminary map for this time frame:

This map essentially merges both days' outlook into one map.  I have the moderate risk out for the first day of the outbreak, but I don't think the threat is large enough to put the moderate risk out for the next day.  Stay tuned!

Notice

As we head into fall, severe weather will start to diminish.  On days where severe weather is nowhere to be found, no severe weather outlooks will be issued.

Severe Weather Outlook

We're going to make this quick and easy today, with no discussion until later in the day.  Because it is Sunday, we should be here for most of the day, barring any unforeseen complications.  Here is the SPC's outlook:

Like I said, this will be quick and easy.  Here is my outlook:

As usual with quick morning outlooks, we will issue any discussion when areas of concern become better defined, such as when a watch is issued by the Storm Prediction Center.  Stay tuned!

Severe Weather Update

Severe thunderstorm watch number 771 has been issued:

Right now, we have a strong cluster of thunderstorms sitting in the north half of the watch area.  While isolated severe is not out of question, the only thing they are really doing is robbing the atmosphere of instability.  Thus, I do believe that the overall threat of this severe thunderstorm watch is a little bit lower than previous watches.  A quick check with the SPC watch probabilities confirms this.  Later today, we should see a few storms develop across the watch area, a few of them severe.  Here is my map:

I really don't think that we will see widespread severe weather from this watch, but a threat exists, so stay tuned.

Severe Weather Outlook

Today's severe weather risk is slightly higher than it has been in previous days, with the SPC issuing a high-end slight risk:

As usual, people in the yellow zone should make sure that they and people around them are aware of the fact that they are at risk for severe weather, including the potential for widespread and significant wind damage, very large hail, and tornadoes.  They should make sure that they have sure that they have an accurate source for receiving watches and warnings as they are issued, and that they know what to do if one is put out.  A complex situation is evolving for tonight, and a discussion will be hard to pin down until a few hours from the event.  Thus, we aren't issuing a very detailed one at this time.  Still, instability and shear should combine to create menacing storms, including supercells, throughout the slight risk area.  A couple of bow echoes should develop, creating potential for widespread wind damage.  Here is my map:

Stay tuned!

Severe Weather Update

All right, we have multiple new watches in effect, so I will post all of the maps here.  First map will be the always updating watch view, whereas the second map is our representation on the risks of thunderstorms.
TORNADO WATCH 767

SEVERE THUNDERSTORM WATCH 768

SEVERE THUNDERSTORM WATCH 769

Stay tuned!