Current D4-8 (May 22-26) SPC Outlook

[Smokin Joe]

ZCZC SPCSWOD48 ALL
ACUS48 KWNS 190828
SPC AC 190828

DAY 4-8 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0328 AM CDT THU MAY 19 2011

VALID 221200Z - 271200Z

...DISCUSSION...

WHILE THE ECMWF AND GFS ARE IN GENERAL AGREEMENT REGARDING THE LARGE
SCALE PATTERN EARLY NEXT WEEK...A SIGNIFICANT DEGREE OF UNCERTAINTY
EXISTS REGARDING INDIVIDUAL SHORTWAVES AND ULTIMATELY THEIR
INFLUENCE REGARDING ORGANIZED SEVERE CONVECTION. WITH UPPER RIDGING
EXPECTED ACROSS THE SERN U.S. AND THE PROPENSITY FOR MODEST SWLY
FLOW FROM THE SRN ROCKIES INTO THE GREAT LAKES...STRONG
THUNDERSTORMS COULD EASILY EVOLVE BENEATH THIS BELT OF STRONGER FLOW
ALOFT...ESPECIALLY GIVEN THE LIKELIHOOD FOR ABUNDANT MOISTURE TO BE
IN PLACE ACROSS THIS REGION. SHORT OF OUTLOOKING THE ENTIRE ZONE
FROM THE SRN HIGH PLAINS INTO THE LOWER GREAT LAKES/OH VALLEY...WITH
LITTLE DAY-TO-DAY DISCRIMINATION POSSIBLE...WILL HOLD OFF FOR
ANOTHER MODEL RUN TO MORE READILY CLARIFY SEVERE POTENTIAL EARLY
NEXT WEEK.

..DARROW.. 05/19/2011



hopefully mother nature throws us a bone

[Derecho]

Sunday night through Monday morning looks impressive for severe thunderstorm action across Southern Ontario. Well, at least on current models. We all know things can change

[davefootball123]

Yup deffenitly. Latest 12z GFS indicates over 1000j/kg CAPE for much of Southern Ontario with Li's to -4 or lower. Lots of moisture with high temps into the mid/upper twenties and points into the twenties. A nice soutwesterly flow. Looking good right now, will have to see. Also Surface to 6km Shear should be around 30kts or so which will be favourable for a damaging winds mabye even an isolated tornado threat

[Derecho]

The plot thickens...

[davefootball123]

I was just taking a look at the NAM sounding for 18z Monday for my area and it was quite impressive. Temps into the mid/upper twenties. I wouldnt be suprised if a few locales in Ontario broke 30 but we will have to see. Dewpoints appear to be in the low 20's meaning Monday(as well as Sunday after the warm front goes through) will be very muggy. A Severe Risk looks quite possible, with the main threats being damaging winds and possibley some large hail with the cool mid/upper level temps indicated on the latest sounding. MLCAPE values of about 1000-1500j/kg and liftied indices of -4 or lower are indicated on both the latest GFS and NAM runs. Also there does appear to be about 30-40kts of 0-6km bulk shear which will be supportive of damaging winds but an isolated tornado cant be ruled out given the 150-250 m2s2 helecity values indicated on the latest NAM. Storms that do form will be moving from the WSW at a mean speed of about 25-35kts.

[Smokin Joe]

was looking at hrrr.....FWIW i know its experimental or whatever and i'm not much of a meteorologist obviously but....

http://rapidrefresh.noaa.gov/hrrrcon...May+2011+-+12Z


and is it me or does it look good for an area west of lake huron but especially between lake huron and lake erie around 4 pm with (maybe) storms firing on the other side of the lake with them heading for a good environment for storms in sw ontario?

if i'm missing something based on this let me know so i can learn what to look for.....

anybody have any info on the next couple days?

[Storm Chaser]

Originally Posted by Smokin Joe

was looking at hrrr.....FWIW i know its experimental or whatever and i'm not much of a meteorologist obviously but....

http://rapidrefresh.noaa.gov/hrrrcon...May+2011+-+12Z


and is it me or does it look good for an area west of lake huron but especially between lake huron and lake erie around 4 pm with (maybe) storms firing on the other side of the lake with them heading for a good environment for storms in sw ontario?

if i'm missing something based on this let me know so i can learn what to look for.....

anybody have any info on the next couple days?

Wow, thats an impressive HRRR run! brings a GREAT storm over my house tonight!

[davefootball123]

SPC now has us in a slight risk for tomorrow. Also alot of development with the numerous tornado watches in the midwest. Gonna be an active couple of days

[obwan]

Just looking at whats firing up on radar, How does that song go?? tonights gonna be a good night

[Itchy]

Well of course this happens at night