Wednesday, May 30, 2012

Large Tornado On Ground- Benjamin, Texas

539
WFUS54 KOUN 302342
TOROUN
TXC275-310030-
/O.NEW.KOUN.TO.W.0051.120530T2342Z-120531T0030Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE NORMAN OK
642 PM CDT WED MAY 30 2012

THE NATIONAL WEATHER SERVICE IN NORMAN HAS ISSUED A

* TORNADO WARNING FOR...
KNOX COUNTY IN NORTHERN TEXAS...

* UNTIL 730 PM CDT

* AT 637 PM CDT...STORM SPOTTERS REPORTED A LARGE TORNADO WAS
LOCATED 9 MILES NORTHWEST OF TRUSCOTT. THE TORNADO WAS MOVING
SOUTHEAST AT 20 MPH. RESIDENTS NEAR TRUSCOTT AND NORTH OF BENJAMIN
SHOULD TAKE SHELTER IMMEDIATELY.

* LOCATIONS IMPACTED INCLUDE...
BENJAMIN...GILLILAND AND TRUSCOTT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THE TORNADO WILL BE HIDDEN BY RAIN AND YOU MAY NOT SEE IT. DO NOT
WAIT. TAKE COVER NOW.

&&

LAT...LON 3384 9990 3384 9985 3382 9982 3382 9976
3368 9953 3351 9990 3382 10000 3384 9999
TIME...MOT...LOC 2337Z 327DEG 16KT 3384 9993

Baseball Size Hail, 80 MPH Winds, Tornado Possible in Paducah, TX Cell

Baseball Size hail, damaging winds above 80 MPH, and a tornado are possible with the cell east of Paducah, Texas.

Multi-Vortex Tornadoes May Be In Progress

Several tight vortexes on radar imagery are showing me that the Paducah, TX cell could have multiple tornadoes associated with it.

Lie updates on the Facebook page.

Extreme Hail May Be Falling East of Paducah, TX

The image below shows VIL, which in very high values, indicates large hail is likely falling.

Live updates on the Facebook page

May 30 2012: Storm Action Day Declared

A Storm Action Day has been declared due to the likelihood of severe thunderstorms in the Southern Plains.

Storm Prediction Center Public Outlook ("Significant" Thunderstorms , "Very Dangerous" Situation)

ZCZC SPCPWOSPC ALL
WOUS40 KWNS 300919
KSZ000-OKZ000-TXZ000-301800-

PUBLIC SEVERE WEATHER OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0419 AM CDT WED MAY 30 2012

...SIGNIFICANT SEVERE THUNDERSTORMS EXPECTED OVER PARTS OF THE
CENTRAL AND SOUTHERN PLAINS LATER TODAY AND TONIGHT...

THE NWS STORM PREDICTION CENTER IN NORMAN OK IS FORECASTING THE
DEVELOPMENT OF LARGE...DESTRUCTIVE HAIL...A FEW TORNADOES...AND
POTENTIALLY WIDESPREAD DAMAGING WINDS OVER PARTS OF THE CENTRAL AND
SOUTHERN PLAINS LATER TODAY AND TONIGHT.

THE AREAS MOST LIKELY TO EXPERIENCE THIS ACTIVITY INCLUDE

SOUTHERN KANSAS
WESTERN AND CENTRAL OKLAHOMA
NORTHERN TEXAS

ELSEWHERE...SEVERE STORMS ARE ALSO POSSIBLE FROM THE CENTRAL HIGH
PLAINS INTO THE OZARK PLATEAU AND NORTHERN TEXAS...

AN UPPER-AIR DISTURBANCE OVER THE NORTHERN HIGH PLAINS WILL PROGRESS
SOUTHEAST INTO THE CENTRAL PLAINS...WHILE A SECOND WEAKER SYSTEM
EMERGES INTO THE SOUTHERN PLAINS FROM THE SOUTHERN ROCKIES. THESE
FEATURES WILL INTERACT WITH A LEE TROUGH/DRYLINE OVER THE HIGH
PLAINS...THE MERGING OF A COLD FRONT AND STATIONARY FRONT OVER
KANSAS...AND POSSIBLY AN OUTFLOW BOUNDARY OVER OKLAHOMA AND
TEXAS...TO PRODUCE A NUMBER OF SEVERE THUNDERSTORMS THIS AFTERNOON
AND EVENING.

THE COMBINATION OF A MODERATE TO STRONGLY UNSTABLE AIR MASS AND
STRENGTHENING VERTICAL WIND SHEAR WILL RESULT IN AN ENVIRONMENT
FAVORABLE FOR SUPERCELLS CAPABLE OF VERY LARGE HAIL AND A FEW
TORNADOES. WITH TIME...INDIVIDUAL STORMS ARE EXPECTED TO MERGE INTO
A LARGE COMPLEX WITH A POTENTIALLY WIDESPREAD DAMAGING WIND THREAT
DEVELOPING ACROSS PARTS OF OKLAHOMA AND TEXAS LATE THIS EVENING INTO
TONIGHT.

STATE AND LOCAL EMERGENCY MANAGERS ARE MONITORING THIS POTENTIALLY
VERY DANGEROUS SITUATION. THOSE IN THE THREATENED AREA ARE URGED TO
REVIEW SEVERE WEATHER SAFETY RULES AND TO LISTEN TO
RADIO...TELEVISION...AND NOAA WEATHER RADIO FOR POSSIBLE
WATCHES...WARNINGS...AND STATEMENTS LATER TODAY.

..MEAD.. 05/30/2012

$$

Tornadoes, Hail are Big Threats Today for Plains

Overall Risk of Severe Weather

Risk of Hail

Risk of tornadoes

Risk of damaging winds
There is a moderate risk of severe thunderstorms as outlined by the Storm Prediction Center for the Southern Plains today. The risk does appear to stem from a tornado and hail threat, more so on the hail threat.

A low pressure system will be stationed in northern Texas, with an occluded front stretching horizontally from central Oklahoma through the Carolinas. As the low pressure center approaches the moderate risk area, a dryline will come out just ahead of the low pressure system. At this point, the front is separating cold and warm air, and the dry line is separating dry and humid air. That makes 2 boundaries separating all types of air masses. Needless to say, that will spark a severe weather event.
The proximity of the front and dry line to the low pressure system lead me to believe that any storms that form may be influenced by the low pressure system's wind field, thus possibly enhancing the risk for tornadoes.

Valid 8:00 PM CDT
At 4:00 PM CDT, a member of the WRF ensembles begins initiation of showers and storms in western Oklahoma. At 5:00 PM CDT, it is evident that these showers and storms may be taking on supercell characteristics, and by 8:00 PM CDT, the storms have merged into a bowing segment or multi-cellular segment. A multi-cell cluster would enhance a hail risk while a bowing segment would enhance wind risk, so this may be a multi-cell cluster.
I used this graphic after comparing its forecasts for now to what was actually happening now, as this ensemble member ran at 0z.

Chase Spot: Weatherford, Oklahoma

Andrew

Tuesday, May 29, 2012

Mess of Watches and Storms Lights Up Northeast

Real Time Watches
Several severe thunderstorm watches and even a tornado watch are in place in the Northeast as strong showers and storms move through the region. It is worth noting that a moderate risk remains in effect for portions of New England, as seen below.

The main risk for these storms are damaging winds, as shown by the Storm Prediction Center. It is well warranted, as many severe thunderstorm warnings indicate that the storms are able to produce winds in excess of 60 MPH.

Andrew

Can a High Pressure in the US Provoke Tropical Activity in the Atlantic?

The concept was brought to my attention that a high in the eastern US or close to the tropics can heighten the potential for tropical systems to form. Today, I decided to act on that concept and see if it was true.

I decided to look at the 2011 hurricane season and use the date of formation to view 500mb maps. Sure enough, in a surprising majority of cases, the tropical system did form when a high pressure system was somewhere in the eastern half of the US.

Now, this was only discovered by me today (although I'm quite sure many others know about this topic), so I don't have too much information on it for now. However, high pressure in the eastern US would most likely act to divert the jet stream north to block any strong winds that may otherwise head to the Gulf and Atlantic. Lack of strong upper level winds is key to have tropical systems form. Additionally, it provides room for the moist, warm Atlantic and Gulf air to possibly rise and give off showers and storms, that may eventually turn into tropical systems.

I looked over the latest ensembles for today, and it does look like a ridge of high pressure will soon return to the eastern US, which may very well give the tropics some room to act up.

Again, this is very preliminary, and I am conducting ongoing research. In my eyes, this could enhance tropical weather forecasts in the future, but let's not get too carried away.

Andrew

'High' Risk of Storms Outlined for Tomorrow in South Plains


With tomorrow's heightened alert by the Storm Prediction Center, I have decided now is a good time to debut The Weather Centre's new storm alert system. Basically, if I see a risk of severe weather is on the horizon, after peering over the models, I will outline areas using the colors on the lefthand part of the screen. Keep in mind this key is only for the risk of storms, as in thunderstorms. When you get into the 'elevated' region is when severe storms become possible.

I have outlined northern Texas and much of Oklahoma under the 'High' risk of thunderstorms, seeing as instability has skyrocketed from the 0z GFS to the 12z GFS. In addition to as much as 4500 j/kg of instability with very little cap to stop storms from forming, shearing on the order of 30 to 50 knots is possible in these areas, leading me to believe that initial storms forming along the dry line may very well be supercells. Eventually, a more large hail risk should develop, and this will be the big risk. Instability as high as 4500 j/kg will promote very strong updrafts. These updrafts will keep pushing rain back up into the clouds to form larger and larger hailstones.

This is not a product of the SPC, NWS, or any government weather service. This is meant as a guidance product and should not be used in place of official government products.

Andrew

Moderate Risk Issued for Tomorrow, May 30

Overall Potential for Severe Weather

Probability of severe weather
There is a 45% chance of severe weather within 25 miles of any point in the northern Oklahoma/south central Kansas areas. 

Thunderstorms should fire along a stationary front connected to a nearby low pressure systen and associated dryline in Texas. The tense clashing of air between the stationary front should result in initiation of showers and storms, likely close to the low pressure system. As the storms form, they will be in the midst of a fair 3000+ j/kg of instability. Hail does appear to be a major threat, with a skew-t from north central Oklahoma identifying up to 1.6 inch hailstones falling.

There will be some potential for tornadoes, but that chance is not high. Eventually, these supercells will converge into one or more clusters and become a more hail/damaging wind threat. I will not rule out the potential for these storms to become derecho formations.

Andrew


Monday, May 28, 2012

Live Pictures Here

I am posting live pictures of severe weather on my weather photography blog:

http://vortexwxphotography.blogspot.com/?m=1

Great Lakes Under Fire From Severe Weather Today

Overall Severe Risk

Risk of Hail
The Storm Prediction Center has outlined a few areas of severe weather potential today, the most prominent areas being in the Great Lakes and Northeast. However, there is a heightened risk of hail in Texas.

It can be expected that showers and storms will develop later into the afternoon in the Great Lakes regions, starting out as supercells. Eventually, these supercells will align to form bowing segments, capable of damaging winds and potentially large hail. These supercells are unlikely to be tornadic, but some rotation does appear to be possible.

As the same cold front extends farther south, there will be a risk for more strong showers and thunderstorms, with hail being the main risk. Thus, strong updrafts and instability can be expected within this region. With the massive heat wave currently engulfing the eastern US, this cool front will be relief for many down South.

A disturbance is in the Northeast region, and should be able to provoke various showers and storms, some of which could be on the stronger side.

Andrew

May 28, 2012 Chase Spot

Initiation of storms should begin in eastern Iowa today. There is a cap over the atmosphere in much of the northern half of Illinois, while the initiation area is free to rise. However, due to worry that cells may not be fully developed right after initiation, I am going to keep the chase spot in western Illinois.

Chase Spot is Morrison, Illinois.
Confidence: Moderate

Sunday, May 27, 2012

Deep Convection in Beryl Aiming for Southeast

As shown in the images below, the strongest convection in Beryl is on either side of the tropical storm. I have a feeling that things will get pretty intense in the Southeast over the next several hours as Beryl makes landfall.

I will finally be able to get onto a computer tomorrow.

Andrew

May 27, 2012 Chase Spot

Shearing and instability are increasing along the cold front currently stationed in Kansas and Nebraska. This increased shearing, combined with strong lower level winds, looks to make for an interesting afternoon, particularly in the south central Nebraska and north central Kansas areas.

Chase Spot: Hastings, Nebraska
Confidence: Moderate-High

Moderate Risk of Severe Weather Today

A moderate risk of severe weather has been issued for Kansas and Nebraska for the potential for large hail, which is the image with the pink. A sounding from KOAX (Omaha, Nebraska) below shows that clouds could spike over 53,000 feet! Since I am on my phone for all day today, check for updates on the Facebook page.

Andrew

Saturday, May 26, 2012

Subtropical Storm Beryl Threatens Jacksonville, Florida

Subtropical Storm (STS) Beryl is projected by the National Hurricane Center to make landfall very close to Jacksonville, Florida, with tropical storm force winds.

Damage to property is possible. A threat to life is possible, especially with flying debris and possible intense flooding rains.

Like our Facebook page on the right sidebar for more information regarding STS Beryl.

Andrew

SPC Extends Memorial Day Severe Risk Back North

As I had expected would happen, the SPC did align with the models an place the slight risk of severe weather through nearly all of the western Great Lakes. Again, I am on my phone, so short updates will go on the Facebook page, which you can find a little ways down the right sidebar.

Friday, May 25, 2012

Subtropical Storm Beryl Forms

Subtropical Storm Beryl has formed offshore the Southeastern US. I am on my phone, so I cannot explain everything, but I have tracks, intensities, and satellite imagery below.

Cumulus Field Appears Over Kansas

A cumulus field has appeared over Kansas, where the cap of atmospheric stability is either broken or will break soon. There is currently 4000 j/kg, or units, of instability over Kansas. Chasers should be ready in the next 30 minutes for initiation.

Andrew

Storms Firing In Iowa

Strong thunderstorms are firing in Iowa, as streamline analysis indicates a tight and contrasting wind field in the Iowa region. There is low instability, so these storms shouldn't get too strong.

Tropical Storm Beryl May Form Today Off the Southeast

There is a high probability (70%) that Invest 94 may very well become Tropical Storm Beryl in the next 48 hours, per the National Hurricane Center. Defined showers and thunderstorms are evident in satellite imagery, yet a lacking well-defined circulation area keeps this system an invest.

http://derecho.math.uwm.edu/models/al942012.png
Tracks for this system are pretty hard to see, but the majority of them do appear to make landfall in the Southwest. Because of this disorganized chaos, I am hesitant to call for a landfalling system. However, I can see enough colors in the picture so that it does appear likely that invest 94 will make landfall in the Southeast.

http://derecho.math.uwm.edu/models/al942012_inten.png
The models are not agreeing with the NHC idea that Invest 94 will become Beryl anytime soon. In the next 2 days, many models actually drop off in strength, which may be due to their ideas of landfall. The more interesting proposal for strengthening does occur around 5 days out, with the majority of models moving towards Tropical Storm strength at that point in time.

Andrew

Thursday, May 24, 2012

Notice

Due to the immaturity of some people on this blog, all comments will now have to be reviewed by me before they are published.

Honestly, if those people are seeing this, I can't believe just how ridiculous your behavior is. I didn't know people could be that malicious, and I hope you're happy that I have to restrict comments at this point. I'm extremely disappointed.

To those that comment with worthwhile information: I sincerely apologize for doing this, however your comments will be published if you do decide to keep commenting with valuable information. Again, I apologize for this.

Andrew

Moderate Risk to Cover Wisconsin, NE Iowa

A moderate risk of severe weather is incoming today for much of Wisconsin, northeast Iowa, southeast Minnesota, and a small part of the northern section of Michigan.

Indications are that severe winds will be possible considering the latest model output, leading the SPC to put in this risk in association with the squall line that will move through this area later today. The concern is that this line will now produce severe winds, thus the upgrade.

Andrew

Multi-Day Severe Weather Threat in the Cards This Weekend

There are two large areas of severe weather outlined by the Storm Prediction Center on Sunday (D4) and Monday (D5), which is Memorial Day (click here to see the post on the Memorial Day threat). It appears that a large low pressure system will be in place over the Northern US. This storm system will have a cold front trailing it, and this front will most likely create the main severe threat. However, seeing as very high temperatures and dewpoints will be in place, pop up storms ahead of the cold front are certainly within the realm of possibility.

Andrew

Memorial Day Holds Large Severe Threat

The Storm Prediction Center has outlined an area from Michigan to Kansas for a risk of severe thunderstorms on Memorial Day. Cities in this risk include Chicago, Illinois, Des Moines, Iowa and Topeka, Kansas.

Discussion
Strong low pressure will be in place over the US/Canada border in the Dakotas region. A warm front will be extending through the Great Lakes, leading temperatures into the upper 90s, likely breaking records in many areas. A cold front will be located in the Plains, but it does appear that scattered showers and storms, potentially severe, will pop out ahead of the cold front. Following those storms, the cold front will gather strength and may come out as a squall line and affect the area highlighted above.
Upper level winds and associated shearing will be located in the northern parts of the risk area, like northern Wisconsin and Michigan.

Andrew

Wednesday, May 23, 2012

Sunday Severe Threat Incorporated into LRC



Sunday's severe weather threat has been found to be incorporated into Lezak's Recurring Cycle, or LRC. Roughly 40-50 days ago, in mid April, we had the tornado outbreak across the central Plains. Severe weather reports are shown below.

As you can see, tornadic storms raced across much of Kansas, some of northern Oklahoma and parts of Iowa and Nebraska. Looking below at 500mb heights from April 14-15, we see a strong trough had shifted into the Plains, producing massive wind shear and a big chance for severe weather. In fact, that day involved the SPC issuing a high risk on Day 2 for only the 2nd time in history, as seen below.
500mb heights from April 14-15, 2012


Evolution of April 14-15 severe weather outbreak risks
The LRC looks to swing a trough into the East again, which has prompted the SPC to issue a risk area in the day 4-8 timeframe. Time will tell, but a storm with connections to the April 14-15 one will certainly be interesting to watch.

Plains Receives Sunday Severe Threat from SPC

The Storm Prediction Center has outlined a large section of the Plains into the upper Midwest for a long range severe weather risk on Sunday. It does appear a disturbance will generate enough heat and humidity to pose for some instability. The jet stream will likely be pumping under this system, so shearing may very well help storms fire in the midst of a potential cap in the atmosphere. This definitely does bear watching.

Andrew

Invest 94 Forms in Caribbean

Invest 94 has formed in the Caribbean seas today, with satellite imagery showing an area of showers and thunderstorms over Cuba to the southwest. There are a few clouds that look very bold. Those are the big time thunderstorms. The colors that are shown along with the satellite imagery shows dry air. As you can see, there is a lot of dry air to the north of the invest, and some to the south.

Believe it or not, this does appear to be the system that I was tracking on the FIM for over a week.

http://derecho.math.uwm.edu/models/al942012.png
Models vary greatly, but from what the FIM was showing a long while ago, the track through western Cuba and to the east of Florida does appear to have the backing of several models and the FIM runs I had been closely watching. There remains potential for this system to move into the Gulf or even hit Florida altogether, but I think I will go with the east of Florida solution for now.

http://derecho.math.uwm.edu/models/al942012_inten.png
Intensity forecasts are pretty weak, whereas the FIM had a full blown tropical storm for this system after it moved through Cuba. However, the heavy majority of models are indicating that it will die out rather quickly and not make much of an impact to land or sea.

Andrew

Tuesday, May 22, 2012

Early Memorial Day Forecast Shows Heat Wave Dominates

An early glance at the forecast for Memorial Day reveals very hot temperatures in store for much of the country, with 90s in Missouri to the Northeast. This would be thanks to a warm front associated with a strong storm system in Canada pulling up all that warm air. Indications are also showing that the air will be pretty humid in the Midwest.

Precipitation looks to be confined to the northeast quadrant of the country, with spotty showers and storms in the region. Florida and the Gulf coast may also get in on some rain.

Alberto Becomes Post-Tropical

Visible Satellite imagery has indicated the dissipation of tropical characteristics of Alberto. As of now, visible imagery is indicating that Alberto is currently a broad area of disorganized showers and thunderstorms. I am seeing no indication of any reformation of Alberto as it moves to the northeast.

Severe Weather Targets the Plains Tomorrow

General Risk of Severe Weather

Probability of a severe weather event within 25 miles of any point.
The Storm Prediction Center is looking for a potential severe weather event for tomorrow in the Plains, with the most intense storms possibly being located in Nebraska. This comes as strong winds in the atmosphere will likely create some ample shearing opportunities, leading to the potential formation of a mesoscale severe weather event. This more intense area of activity may very well be hampered by the lack of any formidable instability. I will keep watching this situation, but as of now, I cannot say that things are looking all too supportive for a widespread severe weather event.

Andrew

Tropical Storm Bud Poses Threat to Mexico

http://derecho.math.uwm.edu/models/ep022012.png
There is a very strong model consensus for Tropical Storm Bud to make landfall as a hurricane in Mexico, as the above image is showing. The models do have conflicting intensity forecasts, but there is indeed a consensus in the works for landfall.

A strong high pressure system will be positioned in the northern Pacific, keeping Bud from shooting out to sea. This high pressure will keep Bud in the relative location it is in, meaning the only solution is for Bud to shift north and east as it tries to get around the high pressure system but inadvertently makes landfall.

http://derecho.math.uwm.edu/models/ep022012_inten.png
There remains a wide spectrum of potential strengths for Bud to achieve. As of now, the highest would be borderline Category 3 hurricane strength, and the minimum would keep Bud in moderate tropical storm status. The NHC forecast, in black, shows a brief Category 1 hurricane strength. I am thinking that this is a pretty reasonable forecast at this time, and I will have another update tomorrow.

Andrew