weather

Time-Shifted Weather

Overheard on Delta Flight 1301 from BWI to MSP: "...you don't have to worry..the snow and ice has melted. I'm telling you it's safe to visit Minnesota!" Not what you want to hear on May 20. What a crazy spring, following a nutty 2012. In fact the last decade has been anything but normal.

This year it's as if Mother Nature took her remote control (the one she clubs us over the head with) and time-shifted spring 3-6 weeks later than usual.

It's been a mixed blessing. The same jet stream dips and bulges that kept us cold & snowy much of spring also pumped Gulf moisture north. The drought is pretty much over in the metro; easing rapidly over central & western counties. These jabs of chilly air are so strong they can cut off from the main jet stream - stalling, spinning like a giant land-hurricane; spiral spokes of moisture rotating around a giant wheel of low pressure stuck over the Plains.

Instability pop-up showers hang on into Wednesday; heavier T-storms Friday. Just enough dry Canadian air pushes south for comfortable sun much of the holiday weekend. Monday looks like the best day for the lake: highs 60s north to low 70s south.

A respectable Memorial Day? Hey, it's safe!

Tornado Nation. We've turned tornado spotting and tornado chasing into something of a sport in this country. Who will get the "money shot" and maybe make a few thousand dollars selling his iPhone video to the local TV station or national weather channel? Last night the reality of tornadoes came into full view. Nature's deadliest wind swept into Moore, Oklahoma, 200 mph winds for 3-6 minutes, and the results were devastating. This EF-4 or EF-5 tornado will probably go down into the record books as the costliest tornado in U.S. history. The loss of life was horrific. As meteorologists we're trained to be clinical as we track and predict all kinds of life-threatening weather. But as a father and human being, you couldn't watch last night's coverage without your heart breaking.

Classic Hook Echo. If you see something like THIS on Doppler you know you have a large, potentially violent tornado. This NWS Doppler (reflectivity) image was taken 10 minutes before Moore suffered a direct hit. The Chief Meteorologist at KFOR-TV in Oklahoma City actually told his viewers "if you don't have a basement you will not survive a direct strike from this tornado - better to get into your vehicle and try to drive away". You don't hear that very often.

* fewer than 1 in 10 Oklahomans have a basement. The reason? Bedrock. It's cost-prohibitive to put in a basement across most of the Sooner State.

* last year I wrote an article for Huffington Post, highlighting a prolifice, well-respected structural engineer/meteorologist who predicts that, within our lifetime, America will be struck by a single urban tornado that claims over 1,000 lives. My jaw dropped when I heard him say this, but after yesterday I'm starting to think he was right.

Velocity Field. Here is the radial velocity Doppler field 10-15 minutes before Moore was struck, a "couplet" showing violently divering winds. Doppler has revolutionized the tracking of tornadoes, but 15-30 minutes before a direct strike it's still impossible to determine the severity of a brewing tornado.

Beyond Words. Usually a tornado is too small to show up on Doppler. Usually. Yesterday's Moore, Oklahoma EF-4+ was 1-2 miles wide, kicking up unprecedented levels of debris as it mowed down neighborhood after neighborhood. The resulting "debris ball", the actual tornado itself, was hard to miss on Doppler. A Tornado Watch was issued for OKC at least 2 hours before the tornado struck, a 30 minute Tornado Warning before the actual funnel struck.

Best Smartphone Weather Warning Apps? Subjective? You bet. Could one of these apps save your life? Absolutely. I've tested a couple hundred weather apps so you don't have to waste your money. Below I have a list of what I consider to be the 3 best, must-have apps for your smartphone. These apps are revolutionizing the way consumers get time-sensitive, potentially life-saving weather warnings. Check below for more details.

Lessons From Moore. There's nothing we can do to stop these terrifying storms, but you can take steps to better prepare. For years I've been talking about "multiple safety nets"; the more sources of tornado information, the better. That means media, social media, e-mail alerts, sirens, NOAA Weather Radio and apps for your smartphone. Details:

1). Take a portable NOAA Weather Radio. The First Alert portable NOAA Weather Radio above costs a whopping $31, and it could save your life .With a little digging you can find portable, hand-held NOAA Weather Radios that should work in rural areas, even the North Woods. Here's a good list of other portable options, thanks to Google. It's true that signal reception can be a problem, but I always camp with a portable NOAA Weather Radio. I may be a weather geek, but I want to live to tell my grandkids about my camping adventures!

2). Situational Awareness. Any good camper can read the sky and (on some level) know if a severe storm is brewing. High humidity, a southeast breeze, building clouds are all tip-offs that storms may be brewing. Wherever you are, hiking, camping, enjoying the outdoors, always have an "escape route" in the back of your mind. Where could you seek shelter if skies turn threatening? Under a rocky overhang, a nearby store or lodge? With a little planning and a Boy Scout "be prepared" mindset you can lower the risk of disaster by thinking and planning ahead.

3). Smartphone apps. This is where the real revolution is taking place in warning technology. There are some terrific apps out there for getting the time-sensitive information you need to stay ahead of the storm. They cost a few bucks, but think of it as another form of life insurance. My company, WeatherNation, offers warning solutions for major corporations, but there are some great options (that aren't in any way related to my business) that can be personalized for the locations you care about, even your real-time GPS location. They're worth every penny:

RadarScope. In my humble opinion this is still the best pure-play radar app. It works anywhere in the USA (you can get a data signal - which can be problematic for parts of the western USA away from cell towers). Click on any NWS Doppler site and see high resolution Doppler radar, an animated loop, hail detection, velocity fields (to see if a storm is rotating and capable of generating a tornado), even storm rainfall estimates - great for determining the risk of flash flooding, which can be VERY important if you've just pitched a tent next to a babbling brook, which might be tranformed into a raging, muddy torrent if 6" of rain falls 20 miles up the road. More details from RadarScope:

"RadarScope is a specialized display utility for weather enthusiasts and meteorologists that allows you view NEXRAD Level 3 radar data along with our most requested new feature, Tornado, Severe Thunderstorm, and Flash Flood Warnings issued by the National Weather Service. It can display the latest reflectivity, velocity, and other products from any NEXRAD radar site in the United States, Guam and Puerto Rico. These aren't smoothed PNG or GIF images, this is real Level 3 radar data rendered in its original radial format for a high level of detail.

This version *now includes* support for Hawaii, Alaska, and Guam!

Whether you are scanning reflectivity for a mesocyclone's tell-tale hook echo, trying to pinpoint the landfall of a hurricane's eye wall, or looking for small features like velocity couplets in the storm relative radial velocity product, only RadarScope gives you the power to view true radial NEXRAD weather radar on your iPhone or iPod touch.

When there are any Tornado Warnings (outlined in RED), Severe Thunderstorm Warnings (YELLOW polygons), or Flash Flood Warnings (GREEN polygons) in effect throughout the US, tap the warning button in the top right corner to browse the list of current warnings, view the details, and even zoom to the selected warning on the map".

PYKL3 For Android. Much of the same functionality of RadarScope can be found in the (new) PYKL3 app for Android phones. Functionality includes:

* NEXRAD Level 3

* Local Storm Reports (LSR)

* SPC Day 1 Outlooks

* SPC Thunderstorm and Tornado Watches

* Summarized Lightning

* NWS Storm Tracks

My-Cast. (no, I don't get a commission). My last company (Digital Cyclone) was sold to Garmin, and they have what I still consider to be the best warning app on the planet. I'm a little biased, yes, but I've tested scores of weather apps and I still think My-Cast Weather Radar, created by Digital Cyclone, is the best overall app for getting storm warnings. You can even set it up to give you "lightning alerts" (if lightning strikes within 20 miles of your location you get an SMS alert, telling you precisely how far away it was, and what direction the strike was). More details:

"The award-winning My-Cast app delivers comprehensive yet intuitive weather information specifically for the iPhone and iPod Touch. Un-cluttered base maps display animated radar, clouds and StormWatch severe weather alerts allowing effortless interpretation of how the weather affects your day. As you check out the current weather, you may see drifting clouds or falling rain as My-Cast's distinctive weather themes come to life. Whether you are interested in weather for today, tomorrow or next week, My-Cast has you covered. When severe weather strikes, My-Cast transmits the latest alerts direct from the National Weather Service.

• Real-time, animated radar
• Weather Map with conditions, temperatures, dew points, wind direction and wind speed overlays
• Animated Visible and Infrared Clouds
• Interactive StormWatch map with National Weather Service alerts
• Complete severe weather warnings, watches, and advisory alert text
• 7-day forecast with high/low temperatures and chance of precipitation
• Hourly forecast with temps, wind speed/direction and chance of precipitation
• Forecast graph including past, present and forecast wind, dew point, temperature, and sky conditions
• Save your favorite and recently viewed locations for anywhere in the U.S.
• Shake for live data refresh
• One-button push for GPS positioning
• No ads!"

Weather Radio. This is another app that sends out real-time warnings, only this one follows the SMS warning with a real-time stream from the local NWS office, so you can hear the latest warnings in audio form, providing another welcome level of detail. More details on Weather Radio:

"Listen to over 170 scanner radio stations providing access to NOAA Weather Radio All Hazards (NWR) broadcasts. NWR is a nationwide network of radio stations broadcasting continuous weather information. NWR broadcasts official Weather Service warnings, watches, forecasts and other hazard information 24 hours a day, 7 days a week. Weather Radio comes with Twitter & Facebook support: tell your friends what station you're listening to, "live", without stopping your audio to invoke an external Twitter or Facebook client! Weather Radio allows users to select from NWR audio streams by State-City, or add your favorite stream."

* all 3 apps are available on iTunes. Some of these may be available for Android and Blackberry as well. It's well worth your time to look into this and download these onto your phone, set up your favorite locations (home, work, cabin, beach, etc) and see how they can give you the information you need to make smarter decisions, and keep your family out of storm-related trouble.

WeatherNation TV. Full disclosure: one of my companies is participating in this new, national weather channel. The mobile app is powerful; in addition to watching the live stream you can personalize and localize your weather, including severe storm updates: 

Severe Alerts – Keep up to date with the latest severe weather for your current location as well as all of your saved favorites.

View – With view feature, you can watch WeatherNation on demand with advanced adaptive bit rate streaming to provide you with the best viewing experience. With WeatherNation’s view feature, you can watch WeatherNation’s 24/7 service LIVE around the clock.

Sync Calendar – With our sync calendar feature, you can automatically and effortlessly look up weather information associated to events on your iPhone’s calendar. It’s a simple way to keep up with the weather wherever you are or may go.

Maps/Radars – WeatherNation provides the latest in storm tracking with our interactive weather maps/radars. You decide the overlays you want to see from radar, satellite, visible satellite, global satellite, advisories, snow depth, current temperatures, current winds, current dewpoint, current humidity, current wind chill, and current heat index. Select specific point data as well like storm cells, storm reports, climate records, or even wildfires. You can also select the type of map you prefer from a standard base map, satellite image base map, or even a hybrid.

From Alerts Broadcaster (issued Monday morning):

* Mild Geomagnetic Storm impacting far northern latitudes - not expected to impact power grid across USA, Asia and Europe right now.

* 17+ U.S. tornadoes in the last 24 hours; another outbreak expected later today over central USA.

* Stalled storm increases flood potential Upper Midwest and Mississippi River Valley.

* 3-10" rains predicted for southern China - more flooding likely.

* "Andrea" in the Gulf of Mexico within 2 weeks?

Low Geomagnetic Storm Risk. Most of the energy from the most recent solar CME is impacting far northern latitudes, north of 60 degrees, but NOAA's Space Weather Prediction Center continues to monitor the current event. Here's the latest: "The almost exclusively northward embedded magnetic field in the CME has resulted in no Geomagnetic Storm conditions at this writing. Things could change quickly if the field goes southward. Check here for status updates."

Volatile, Violent Pattern. Updated last night: Dynamics are favorable for more tornadic storms again today over the nation's midsection. As many as 17 tornadoes touched down Sunday from Texas to Missouri, including the possible EF-4 or EF-5 tornado that ravaged Moore, Oklahoma. More details on Monday touchdowns from SPC.

Another Moderate Threat Today. It's worth repeating that when NOAA SPC upgrades the severe risk from "slight" to "moderate" it's a pretty good tip-off of larger, long-track tornadoes, the ones that produce most of the damage and injuries. The highest risk area today is from Tulsa to Joplin, Columbia and the suburbs of Kansas City, but an isolated tornado can be expected across Iowa, western Illinois, even southwest Wisconsin.

* It's worth pointing out that SPC did have much of Oklahoma in a moderate risk; not the immediate Moore area, but when the moderate risk is that close you know it could be a very busy day with an enhanced risk of large, violent, long-track tornadoes.

Soggy Holding Pattern. Once again weather systems have stalled, allowing a persistent fetch of warm, moist, unstable air from the Gulf of Mexico to surge northward, repeatedly, day after day, fueling a slow-moving storm in the upper atmosphere. 2-4" rains have already been reported since late last week over the Upper Midwest, where topsoil is saturated, waterlogged. Any additional downpours later today and tomorrow will run off into streets and streams. Flood Watches are posted for much of North Dakota, Minnesota and western Wisconsin; flood warnings (meaning flooding is being reported) from southeastern Minnesota into Illinois and Missouri as the Mississippi River continues above flood stage.

More Flooding For South China. Computer models show an additional 3-10" rain over the next week over much of southern China. More flash flooding and river flooding can be expected with possible impacts to facilities and transportation.

Andrea? We're going out on a limb here, but in the spirit of trying to give you as much of a heads-up as possible, long-range models continue to suggest tropical development in the Caribbean, with a possible tropical storm entering the Gulf of Mexico the first few days of June. Confidence levels are low, but facilities from Texas to Florida should remain alert. I have a hunch hurricane season may come early this year.

Summary: The latest X-class solar flare (there have been 4 since Mother's Day) produced a CME (Coronal Mass Ejection) capable of minor fluctuations to the grid, mainly over far northern latitudes over the next 24 hours. NASA and NOAA don't appear particularly concerned over this outbreak of Space Weather; we'll continue to monitor conditions, which can change quickly. Another tornado outbreak over the central USA is likely later today; an atmospheric holding pattern squeezing out more flooding T-storms as far north as the Twin Cities, Madison and Fargo. Many streams and rivers will continue to flood across southern China, and we're watching for possible tropical development in the Gulf of Mexico or Caribbean within 2 weeks. If sustained winds top 39 mph we'll have Tropical Storm Andrea. It's still (very) early, and we'll watch the tropics and keep you posted.

Mostly Soggy Into Friday, Then A Break? The ECMWF guidance is encouraging for the weekend, a wet start Saturday giving way to mostly-dry conditions Sunday and Memorial Day. I know - a holiday. What can possibly go wrong. Nothing severe, no 100-degree heat spikes either. A chilly, rainy Wednesday gives way to highs near 70 by the weekend.

TODAY: Lingering showers, rumble of thunder? Winds: SW 8-13. High: near 70

TUESDAY NIGHT: Showers diminish - still damp. Low: 53

WEDNESDAY: More showers, cooler. High: 59

THURSDAY: Partly sunny and pleasant again. Wake-up: 49. High: 68

FRIDAY: Showers and T-storms likely (heaviest southern MN). Wake-up: 51. High: 67

SATURDAY: Wet start, then peeks of PM sun. Wake-up: 52. High: 69

SUNDAY: Partly sunny, cool breeze. Wake-up: 53. High: 68

MEMORIAL DAY: Not bad for a holiday. Mild sun. Wake-up: 50. High: 71

* cumulonimbus image above courtesy of Edward Sklar.

Not Out of the Woods

By Todd Nelson

Wet enough for ya? Not sure how much more rain my yard can take. Between the puddles and the neighbors doggie landmines, not sure I'll be playing bocce ball anytime soon.

Scattered showers and storms are in the forecast again Sunday as the storm system continues to wobble overhead, what else would you expect? Some of the isolated storms that develop later Sunday across southeastern Minnesota could be a little on the more vigorous side.

A cooler and more stable air mass moves in on the northern side of the low by Tuesday and Wednesday with mainly just lingering rain showers. I think the clouds will finally get out of here by the end of the week and you might actually be able to get out and mow that lawn if you haven't already.

I'm curious to see how the Minnesota drought will have changed after all this rain. My hunch is that many of those smaller swamps and ponds close to home will have filled up quite nicely; perfect for a fresh brood of skeeters. In no time you'll be slapping those pesky blood suckers... Welcome to Minnesota where Mosquitoes are as big as buzzards. Don't forget to check the kids for ticks if they're in tall grass or the woods!

________________________________________________________________

Todd's StarTribune Outlook for the Twin Cities and all of Minnesota

MONDAY: Lingering shower/storm possible early AM. Breaks of midday sun, then more showers/storms develop by late afternoon/evening across southeastern Minnesota (some could be strong). High: 78. Winds: SE 10-15

MONDAY NIGHT: Showers and storms possible overnight. Low: 58

TUESDAY: Cooler. Lingering light rain showers, isolated thunder. High: 73

WEDNESDAY: Damp. Cloudy and cooler with passing showers. Wake-up: 51. High: 62

THURSDAY: Ditch the umbrellas! More sun. Wake-up: 47. High: 67.

FRIDAY: Smells of SPF return. Warmer with more sun. Wake-up: 47. High: 71.

SATURDAY: Warmer. Increasing clouds with an isolated PM shower/storm? Wake-up: 52. High: 73.

SUNDAY: Unsettled. Afternoon grilling plans may be delayed due to spotty thunder? Wake-up: 55. High: 75

__________________________________________________________________

Flash Flood Watch

With recent heavy rainfall and more potentially on the way, there remains a Flash Flood threat across parts of Minnesota and Wisconsin through Monday evening. Additional 1" to 3" of rain may be possible in areas that see thunderstorms.

Scratch and Sniff?

Thanks to my good friend Jill Stewart Kellar for the picture below who said that she wished the picture was 'scratch and sniff' - LOL - It looks AMAZING, but it can't smell it!

Wind Map

Here's an interesting look at wind flow across the country. Note the southerly wind flow east of the two low pressure systems. This is responsible for the warm and humid air that has been in place across the middle part of the country as of late. This has also helped set the stage for all the severe weather that we've seen over the last few days.

See the latest wind flow map HERE:

 Radar From Sunday...

Take a look at how active the radar was across the middle part of the country from Minnesota to Oklahoma. At this on Sunday, there were a number of watches and warnings in progress and there had been reported tornadoes in Kansas and Oklahoma!

Severe Storm Reports

Here are a few of the storm reports from the very active Sunday across the middle part of the country.

Oklahoma Damage

Take a look at this photo taken in Luther, OK from the Oklahoma County Sheriff's office on Sunday evening.

 Oklahoma Tornado

It's amazing what technology can do in this day in age... Take a look at the radar image from Oklahoma Sunday evening northeast of Oklahoma City, OK near Fallis, OK. The classic "Hook Echo" with red and green close to gether on the velocity signature indicatues intense rotation.

This is what it looked like in a 3D view... It's almost like you can see the tornado touching the ground!

Thanks to my good friend Amy Bettwy for the picture below... in the new radar upgrade to Dual Pole Radar, you can actually see a "TDS" or a Tornado Debris Signature! In the image below, you can see a dark spot over Fallis, OK where the Dual Pole radar may actually be picking up debris vaulted high in the air!

Severe Threat Continues...

The Storm Prediction Center continues the severe thunderstorm threat for Monday across the middle part of the country. Keep in mind that this threat will likely change as the storm continues to settle into the middle part of the country.

Severe Threat Monday

...SOUTHERN PLAINS TO MID MS VALLEY...

SECONDARY MID LEVEL SPEED MAX...ON THE ORDER OF 60KT AT 500 MB...IS
EXPECTED TO EJECT ACROSS THE SRN ROCKIES INTO NRN OK BY 21/00Z.
WHILE LATE DAY1 CONVECTION MAY DISTURB LOW LEVEL WIND FIELDS ACROSS
PORTIONS OF SERN KS INTO MO...IT APPEARS LARGE SCALE INFLUENCE OF
APPROACHING SPEED MAX SHOULD SHARPEN SYNOPTIC FRONT ACROSS OK BY
PEAK HEATING. THIS WILL BE THE PRIMARY FOCUS FOR RENEWED SEVERE
THUNDERSTORM DEVELOPMENT ACROSS THE MDT RISK REGION.

THUNDERSTORMS...A FEW SEVERE WITH A THREAT OF HAIL...MAY BE ONGOING
AT THE BEGINNING OF THE PERIOD ACROSS SERN KS/MO ALONG THE NOSE OF
VEERED LLJ. THIS CONVECTION MAY TEMPORARILY DISPLACE THE SYNOPTIC
FRONT OR PERHAPS EVEN PRODUCE OUTFLOW THAT BECOMES A FOCUS FOR
AFTERNOON CONVECTIVE DEVELOPMENT. STRONGEST BOUNDARY LAYER HEATING
IS EXPECTED ACROSS WEST TX INTO SWRN OK WHERE SFC TEMPERATURES
SHOULD SOAR INTO THE 90S. ALONG/NORTH OF THE MAIN MID LEVEL JET
CORE MID LEVEL TEMPERATURES SHOULD COOL SUCH THAT DEEP CONVECTION
WILL EASILY DEVELOP ALONG AFOREMENTIONED CONVECTIVE OUTFLOW BOUNDARY
INTO MO AND SHARPENING COLD FRONT/DRYLINE FARTHER WEST. IN
FACT...TSTMS MAY DEVELOP BY 20-21Z ACROSS OK WHERE SBCAPE IS
EXPECTED TO BE IN EXCESS OF 3000 J/KG. FORECAST DEEP LAYER
SHEAR...IN EXCESS OF 50KT THROUGH 6KM...AND THE PROSPECT FOR A VERY
MOIST WARM SECTOR FAVOR NUMEROUS SUPERCELL STRUCTURES...AT LEAST
THROUGH MID EVENING OF THE CONVECTIVE CYCLE. VERY LARGE HAIL AND
TORNADOES ARE POSSIBLE WITH SUPERCELLS AND WITH TIME ONE OR MORE
MCS/S SHOULD EVOLVE ALONG NOSE OF STRENGTHENING LLJ OVER OK. AMPLE
MID LEVEL FLOW WILL EXTEND ALONG THE DRYLINE INTO THE EDWARDS
PLATEAU OF TX SUPPORTIVE OF ISOLATED SUPERCELL STRUCTURES CAPABLE OF
PRODUCING AT LEAST LARGE HAIL AND DAMAGING WINDS.


...UPPER MS VALLEY/GREAT LAKES...

LATEST MODEL GUIDANCE SUGGESTS A MID LEVEL SHORT WAVE TROUGH/SPEED
MAX WILL ROTATE NEWD ACROSS IA/IL INTO MN/WI DURING THE AFTERNOON
HOURS. THIS FEATURE WILL SERVE TO INCREASE UVV ACROSS A FAIRLY
MOIST/UNSTABLE BOUNDARY LAYER SOUTH OF SHARP WARM FRONT THAT WILL
EXTEND FROM LOW NEAR THE ND/SD/MN BORDER...EWD INTO NRN WI AT PEAK
HEATING. WHILE SHORT WAVE TROUGH WILL INFLUENCE/SUPPORT DEEP
CONVECTION...STRONG BOUNDARY LAYER HEATING WILL PROVE INSTRUMENTAL
IN DESTABILIZATION ACROSS MN/WI AND SBCAPE COULD EASILY RISE TO NEAR
2000 J/KG. DISCRETE SUPERCELL STRUCTURES MAY EVOLVE WITHIN THIS
AIRMASS AND WITH RELATIVELY LOW CLOUD BASES ISOLATED TORNADOES...IN
ADDITION TO LARGE HAIL MAY BE OBSERVED.

Severe Threat Tuesday

...SYNOPSIS...
SLIGHT WEAKENING/DEAMPLIFICATION OF THE LINGERING MID- AND
UPPER-LEVEL STORM SYSTEM OVER THE CENTRAL U.S. IS FORECAST THIS
PERIOD...AS A DIGGING/STRENGTHENING TROUGH/LOW SHIFTS SSEWD INTO THE
WRN/NWRN U.S. THROUGH THE END OF THE PERIOD. THE CENTRAL U.S.
SYSTEM WILL REMAIN THE PRIMARY DRIVER FOR THE MAJORITY OF THE
CONVECTIVE POTENTIAL THIS FORECAST.

...UPPER GREAT LAKES REGION SWWD INTO CENTRAL TX...
MODEL DIFFERENCES WITH RESPECT TO TIMING OF A SHORT-WAVE TROUGH
ROUNDING THE SRN PERIPHERY OF THE UPPER LOW AND WIDESPREAD
CONVECTIVE ACTIVITY DURING INTERVENING DAYS IS YIELDING FAIRLY
SUBSTANTIAL UNCERTAINTY WITH RESPECT TO DETAILS OF THE DAY 3
/TUESDAY/ SEVERE WEATHER POTENTIAL STRETCHING FROM THE GREAT LAKES
TO TX.

ATTM...IT APPEARS THAT A COLD FRONT -- MOVING ACROSS THE CENTRAL AND
SRN PLAINS AT THE START OF THE PERIOD -- SHOULD BEGIN TO WASH OUT AS
EWD PROGRESSION SLOWS INTO THE AFTERNOON. WHILE CLOUDS AND ONGOING
SHOWERS AND THUNDERSTORMS AHEAD OF THE FRONT WILL LIKELY INHIBIT
HEATING/DESTABILIZATION IN SOME AREAS INTO THE
AFTERNOON...SUBSTANTIAL DESTABILIZATION IS FORECAST BY LATE
AFTERNOON -- PARTICULARLY FROM THE SERN OK/WRN AR VICINITY SWWD INTO
CENTRAL TX AHEAD OF THE DRYLINE.

BOUNDARY-LAYER CAPPING SHOULD LIMIT DEVELOPMENT INTO THE
AFTERNOON...BUT STORM DEVELOPMENT IS EVENTUALLY EXPECTED -- WITH
COVERAGE DEPENDING TO SOME DEGREE UPON TIMING OF A SHORT WAVE TROUGH
CROSSING THE SRN ROCKIES DAY 2 AND THEN SHIFTING INTO TX DAY 3.
WITH AMPLE SHEAR AND LIKELY-TO-BE STRONG INSTABILITY ACROSS THE
ARKLATEX AND INTO CENTRAL TX...SIGNIFICANT SEVERE WEATHER --
PRIMARILY VERY LARGE HAIL -- WILL BE POSSIBLE. HOWEVER...WITH
QUESTIONS REGARDING CONVECTIVE COVERAGE/CONCENTRATION...WILL
INTRODUCE ONLY 15% SEVERE PROBABILITY ATTM.

FARTHER N -- ACROSS MO AND AS FAR NEWD AS THE UPPER GREAT LAKES
REGION...THE SCENARIO IS EVEN MORE UNCLEAR...AS MORE WIDESPREAD
STORMS ONGOING EARLY IN THE PERIOD WILL LIKELY PERSIST THROUGH THE
DAY. THEREFORE...MORE UNCERTAIN DEGREE OF DESTABILIZATION -- AS
WELL AS GENERALLY WEAKER SHEAR DUE TO MORE MERIDIONAL/UNIDIRECTIONAL
FLOW ALOFT -- SHOULD LIMIT THREAT TO SOME DEGREE. STILL...LOCALLY
SEVERE STORMS CAPABLE OF PRODUCING HAIL AND DAMAGING WINDS AND
POSSIBLY AN ISOLATED TORNADO CAN BE EXPECTED. THREAT SHOULD
DIMINISH OVERNIGHT...THOUGH STORMS/LIMITED POTENTIAL FOR SEVERE
WEATHER WILL CONTINUE THROUGH THE END OF THE PERIOD.

 Minnesota Storms

Thanks to my good friend Ben Lewis for this picture out of the Twin Cities. Heavy rain and gusty winds was all he reported on what he called a "Lil Baby Chase" - LOL - Thanks Benny!! 

 

More Heavy Rain on the Way...

The same slow moving storm system will be responsible for additional heavy rainfall across the middle part of the country through midweek. There still may be additional 1" to 3"+ amount by Wednesday!

Thanks for checking in, have a great week ahead!

Don't forget to follow me on Twitter @TNelsonWNTV

Stormy Swirl. NWS Doppler at 6:46 shows the strongest T-storms pushing north of the Twin Cities and St. Cloud, moving toward Duluth. Another line of moderate to heavy T-storms is approaching from the west, but the storms that blew thru with 1" hail and winds gusting to 58 mph stabilized the atmosphere, reducing the threat of tornadoes.

Minor Damage. NWS data shows 1" rains at Chanhassen, winds gusted to 58 mph at Woodbury, with reports of downed trees and powerlines in western Wisconsin. No tornado reports. More details here.

Severe Storm Warning. NWS Doppler radar at 5 pm shows a swirl of strong/severe storms pushing toward the north northwest; a significant risk of penny size hail, winds topping 60 mph, frequent lightning, and flash flooding. Details:

BULLETIN - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WARNING

NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN

454 PM CDT SUN MAY 19 2013


THE NATIONAL WEATHER SERVICE IN THE TWIN CITIES HAS ISSUED A


* SEVERE THUNDERSTORM WARNING FOR...

  SOUTHERN WASHINGTON COUNTY IN EAST CENTRAL MINNESOTA...

  WESTERN PIERCE COUNTY IN WEST CENTRAL WISCONSIN...

  SOUTHWESTERN ST. CROIX COUNTY IN WEST CENTRAL WISCONSIN...


* UNTIL 530 PM CDT


* AT 450 PM CDT...A LINE OF SEVERE THUNDERSTORMS WAS LOCATED ALONG A

  LINE EXTENDING FROM 13 MILES SOUTHEAST OF EAGAN TO 11 MILES

  NORTHWEST OF RED WING TO 8 MILES SOUTHEAST OF RED WING...AND MOVING

  NORTH AT 50 MPH.
 

  HAZARD...60 MPH WIND GUSTS.


  SOURCE...RADAR INDICATED.


  IMPACT...EXPECT DAMAGE TO ROOFS...SIDING AND TREES.


* LOCATIONS IMPACTED INCLUDE...

  ELLSWORTH...RIVER FALLS...HUDSON...STILLWATER...PRESCOTT...DIAMOND

  BLUFF...HAGER CITY...BAY CITY...COTTAGE GROVE...ESDAILE...

  WOODBURY...AFTON...BELDENVILLE...LAKELAND...LAKE ELMO...NORTH

  HUDSON...BAYPORT...BURKHARDT...OAK PARK HEIGHTS AND MARTEL.