Discussion & Reporting 2007

[Paul Sherman]

Just a quick note to let you all know how it is hopefully going to pan out on this years Chase, like last year we will be having a Discussion thread and a reporting thread for pictures the following day.

Eg

Monday 30th April - If storms are possible for the 1st Chase Day on 1st May then we will post a 01-05-07 Discussion thread which you all should have by the time you wake up on that Tuesday morning, please feel free to add to the discussion but be aware of the time difference as we will be 6 hours behind you all here and 7 if in Colorado and parts of New Mexico, so if we dont reply its not because we dont like you it will probably be because as you post at 9am we will still be dreaming of Tornadoes at 3am in the morning. That night we will post up the pictures and the report ( 01-05-07 Reports ) and also post a new discussion for 02-05-07 and so on, every morning you should all have something to look at and drool over

Another scenario that cropped up last year was this scenario, we were waiting for things to kick off and had good Wifi access meaning we were online and chatting to members on here ( USA 3pm ) ( UK 9pm ) and then suddenly everything went quiet as we had seen the storm to chase and gone after it hence losing our Wifi link, some members thought we were still sitting in our Target location and not even chasing the storms, well this year we will be sending texts back to a few members who have volunteered to be online and they will then post up exactly where we are in relation to the Storm and also alert you at the exact time we see a Tornado if one occurs, that way you can all track what storms we are on all the time, also in my 2nd stint Steves Team will have a live GPS Tracker showing exactly where we are and it even moves down roads on GPS :unsure:

So what is it looking like for our trip in just over 12 days time, the following from the Models is a Snapshot of our Landing day and up to 1st May, it's not looking bad at the moment with a very mobile pattern signified, this can all change of course but with a raging Jetstream in exactly the place we would want it is a bonus, also Temps could be in the thirties when we land with quite a pronounced Dryline and pressure is Low.

- JetStream & Sea Surface Pressure

- Temps for 29th April PHEW!!

- sOME 1000-1400 Cape

Will add on the 30th & 01st May in a little while but suffice to say its looking good at the moment

Paul Sherman

[Paul Sherman]

Here is the 1st May Currently as it stands atm, but this could and probably will change.

- 1st May Raging Jet Stream

- Hope they all like it Hot !!

- 1,500 Cape

- Anyone for a bit of Dryline Magic in the Panhandles

- Nice Southerly Flow

Paul Sherman

[Nick F]

Some mixed outlooks for our arrival.

GFS shows sfc low over Wern Plains on Sunday 29th evening when we land, some CAPE and a dry line over Wern Plains though jet way to the North - some storms poss. but nowt severe over TX (00z charts below will be roughly 18z over there with time difference):

Monday: Some decent CAPE and high DPs over TX and Sern OK, though jet and best shear to North again over Kansas Nebraska, Dakotas:

ECM, which is rated better over GFS in the US, less optimistic for first few days with a ridge present:

First chase day with whole team on Tues May 1st looking a little dead in the water with a cool NW flow:

... but hey, at t+276 it's a long way off and subject to change, pattern looks fairly mobile from the West over US for start of May - so should be good opportunities for us hopefully, even if the first few days look quite quiet.

[kold weather]

0z runs both have a moderate ridge over the USa in some form or another. The GFS loses that NW flow pretty quickly:

Anyway the 1st of May looks similar to last nights progs, IE the cape is ready in decent supply but the jet stream lays to the north.

right now the 2nd looks okay, with a jet streak pushing upfrom the SW over the southern part of the plains with some decent cape as well and some shear there should be storms with that but we've got a long way to go before that. CIN looks okay as well, not to omuch but it should hopefully limit the chance sof it becoming just another load of mess againand keep the cells fairly discrete.

[Paul Sherman]

Okay could be time to get excited for our trip, Lots of chat about the next "BIG STORM" System with a Negative Tilted Low pressure bombing into the Plains around the 4th May. This could be a Big Storm on current models and has held together for some time now, I picked up on this from around 340 hours now down to 240 hours, Keep this one in mind

Paul Sherman

EDIT : In fact looks like the Thur 3rd should be the "Day before the Big Day" event as well.

Hope the guys are ready for this

[Anti-Mild]

Good luck with that BIG STORM system Paul, but above all, stay safe!!

[pottyprof]

Looking interesting for our team. Jim Leonard feels that it could very well be a good trip..

http://www.stormtrack.org/forum/showpost.p...mp;postcount=22

[Roger J Smith]

Latest model forecasts continue to look promising for the early days of the storm chase, by Tuesday 1 May hot and humid southerly flow develops over most of TX with weak dry line feature in e NM, then this develops gradually 2-3 May with lower pressure developing Colorado to Kansas. Should be a very good set up for severe storms by Wed-Thurs, but not too suddenly for the planned arrival date.

[Nick F]

Some encourarging patterns emerging for next week on tonight's output, ECMWF model - which tends be rated more highly than GFS over in the US, is indicating a classic trough setting up over the Rockies by Sat 5th May- dragging up a warm moist Serly flow over the plains:

Friday 4th:

Saturday 5th:

#

12z GFS was showing even more armageddon style charts earlier, as early as wednesday it was looking good for storms over Sern Plains ... waiting for the 18z to roll out now ... so far so good for next week - with severe potential increasing around 3-5th May.

[Paul Sherman]

Some Charts to make our mouths water before we go, have never seen the Models like this, and the very last one if it verifies could delay the guys flights on the 11th Oh well $hit Happens I suppose

Of course these are a long way off but the potential is there, Following are CAPE Charts and they show the Potential energy.

- 6pm Tuesday 1st May 2007

- 6pm Wednesday 2nd May 2007

- 6pm Thursday 3rd May 2007

- 6pm Friday 4th May 2007

- 6pm Saturday 5th May 2007

- 6pm Sunday 6th May 2007

- 6pm Monday 7th May 2007

- 6pm Tuesday 8th May 2007

- 6pm Wednesday 9th May 2007

- 6pm Thursday 10th May 2007 ** Last Chase Day for the Others **

- 6pm Friday 11th May 2007 **About the time they fly back **

Paul Sherman

[pottyprof]

Hmm.. You been playing with paint again Paul??.. :lol:

[Anti-Mild]

Gawd! Thursday looks promising!!

[Paul Sherman]

http://www.stormtrack.org/forum/showthread.php?t=12173

RAMP ALERT # RAMP ALERT

Well this looks like it is coming into the Timescale now for a Pretty Big Outbreak !!

Looks like we have picked well, could be 8 straight days of chasing, and also the 2 days before the major outbreaks should see some upslope flow and SW Texas action, could it be every day for a Chase day for the lucky other 5 !!

Starting to get really excited now.

Paul Sherman

[Nick F]

Just been looking at the latest NOAA/NCEP Extended Forecasts and Prognostic Discussions, and it looking good for mid to late next week. When we land they are suggesting strong ridging and some high temps Sun/Mon over the Plains- with perhaps record temps in places. By mid-week trough will slowly move in from the West with destabilisation and convection mid/late week over the Plains:

...CENTRAL/WEST...

STRONG RIDGING DAYS 3 AND 4 SUN/MON OVER THE WEST AND PLAINS WILL

BRING VERY WARM TEMPS WITH ANOMALIES IN THE 15 TO 25 DEGREE RANGE

WITH SCATTERED RECORD HIGH TEMPS. DIGGING WRN TROF AND ERN CONUS

AMPLIFICATION WILL KEEP RIDGING MID NATION BUT PROGRESS THE RIDGE

AXIS EWD TO ALONG THE MS VLY. PLAINS TEMPS WILL REMAIN ABOVE AVG

BUT A SLOWLY EJECTING MID LEVEL TROF WILL AID IN DESTABILIZATION

AND CONVECTION KEEPING TEMPS COOLER MID TO LATE WEEK.

http://www.hpc.ncep.noaa.gov/discussions/pmdepd.html

... also:

6-10 DAY OUTLOOK VALID FOR MAY 02 - 06 2007 TODAYS MODEL GUIDANCE IS IN GOOD AGREEMENT IN DEPICTING A HIGHLY AMPLIFIED 500-HPA PATTERN OVER NORTH AMERICA. ALL ENSEMBLE MEAN SOLUTIONS INDICATE A DEEP TROUGH OVER THE WEST... A SHARP RIDGE ACROSS THE MISSISSIPPI VALLEY AND A MODERATELY AMPLIFIED TROUGH OFF THE NEW ENGLAND COAST. THE MOST EVIDENT CHANGE FROM YESTERDAYS MODEL SOLUTIONS IS THE INCREASING AMPLIFICATION OF THE 500-HPA PATTERN OVER NORTH AMERICA AND ADJACENT WATERS. SLIGHT DIFFERENCES REMAIN IN THE DEGREE OF AMPLIFICATION WITH THE GFS-BASED ENSEMBLE MEAN SOLUTIONS MORE AMPLIFIED THAN THE 0Z CANADIAN AND 12Z ECMWF ENSEMBLE MEAN SOLUTIONS. THE 0Z ECMWF SUPPORTS THE MORE AMPLIFIED PATTERN PREDICTED BY THE GFS-BASED ENSEMBLE MEAN SOLUTIONS. THE POSITIVE 500-HPA HEIGHT ANOMALY CENTERED ACROSS THE NORTH ATLANTIC FAVORS NEGATIVE 500-HPA HEIGHTS OVER THE CANADIAN MARITIMES. CONFLUENT FLOW AT THE MID-LEVELS OF THE ATMOSPHERE SHOULD INCREASE SURFACE PRESSURES OVER EASTERN CANADA AND LEAD TO NORTHERLY FLOW INTO THE NORTHEAST. THEREFORE... NEAR TO BELOW NORMAL TEMPERATURES ARE FORECAST FOR THE NORTHEAST. ABOVE NORMAL 500-HPA HEIGHTS SUPPORT ABOVE NORMAL TEMPERATURES FOR THE REMAINDER OF THE EAST AND CENTRAL CONUS. DUE TO THE MORE AMPLIFIED TROUGH OVER THE WEST... BELOW NORMAL TEMPERATURES HAVE BEEN EXPANDED ACROSS THE WEST. WITH THE EXPECTED HIGHLY AMPLIFIED 500-HPA TROUGH ESTABLISHED OVER THE WEST... A WETTER-THAN-NORMAL WEATHER PATTERN IS ANTICIPATED FOR MUCH OF THE WESTERN AND CENTRAL CONUS. THE GREATEST UNCERTAINTY IN THE PRECIPITATION FORECAST EXISTS ALONG THE EAST COAST. AT THE BEGINNING OF THE PERIOD... A COLD FRONT IS EXPECTED TO PROGRESS SOUTH ACROSS THE MID-ATLANTIC. AS THE FRONT BECOMES STATIONARY LATE NEXT WEEK... IT WILL LIKELY BECOME A FOCUS FOR DAILY PRECIPITATION. HOWEVER... FORECASTING THE EXACT LOCATION OF THIS FRONTAL BOUNDARY IS A CHALLENGE. THE MOST PROBABLE AREA FOR ABOVE NORMAL PRECIPITATION IS THE SOUTHERN MID-ATLANTIC. BELOW NORMAL PRECIPITATION IS FORECAST FOR THE NORTHEAST AND DRIER-THAN-NORMAL CONDITIONS SHOULD PERSIST FOR THE SOUTHEAST. ELSEWHERE... BELOW NORMAL PRECIPITATION IS FORECAST FOR MUCH OF ALASKA.

8-14 DAY OUTLOOK FOR MAY 04 - 10 2007: THE HIGHLY AMPLIFIED 500-HPA PATTERN FOR EARLY MAY SHOULD CONTINUE INTO WEEK 2. THE VARIOUS GFS ENSEMBLE MEAN SOLUTIONS MAINTAIN THE AMPLIFIED PATTERN WHILE THE 0Z CANADIAN ENSEMBLE MEAN INDICATES NEARLY ZONAL FLOW. DUE TO A LACK OF CONTINUITY... THE 0Z CANADIAN ENSEMBLE MEAN WAS DISCOUNTED AS AN OUTLIER TODAY. THE OFFICIAL BLENDED HEIGHT CHART INDICATES THAT BELOW NORMAL 500-HPA HEIGHTS WILL PERSIST OVER THE WEST WITH ABOVE NORMAL 500-HPA HEIGHTS FROM THE MISSISSIPPI VALLEY TO THE EAST COAST. SINCE THE 500-HPA PATTERN OVER NORTH AMERICA REMAINS STABLE... THE TEMPERATURE AND PRECIPITATION FORECAST WILL BE SIMILAR TO THE 6-10 DAY PERIOD. A SLIGHT PROGRESSION OF THE LONGWAVE TROUGH OVER THE WEST SHOULD RESULT IN A COOLING TREND ACROSS THE PLAINS. ABOVE NORMAL TEMPERATURES SHOULD CONTINUE ACROSS THE MISSISSIPPI VALLEY AND SOUTHEAST WHILE THE WEST REMAINS COOLER-THAN-NORMAL. BELOW NORMAL TEMPERATURES ARE FORECAST FOR NORTHERN ALASKA WITH NEAR TO ABOVE NORMAL TEMPERATURES FOR THE REMAINDER OF ALASKA. DRIER-THAN-NORMAL CONDITIONS SHOULD ACCOMPANY THE ABOVE NORMAL TEMPERATURES ACROSS THE EAST. MEANWHILE... A STORMY WEATHER PATTERN WILL CONTINUE FOR THE GREAT PLAINS AND MISSISSIPPI VALLEY. PRECIPITATION TOOLS SUGGEST THAT THE HIGHEST LIKELIHOOD FOR ABOVE NORMAL PRECIPITATION EXISTS ACROSS THE NORTHERN PLAINS. MUCH OF THE WEST SHOULD REMAIN WETTER-THAN-NORMAL DUE TO THE PRESENCE OF THE AMPLIFIED TROUGH. ELSEWHERE... BELOW NORMAL PRECIPITATION WILL CONTINUE FOR MUCH OF ALASKA.

http://www.cpc.ncep.noaa.gov/products/pred...day/fxus06.html

[Gorky]

Looks like we could be storm chasing from the airport the day we fly back given those charts

[Paul Sherman]

Dont think we could have picked a better time Nathan, looks like we will be VERY Busy from about when we land, maybe I will get a rest when you lot come home

Paul S

[Gorky]

I'm guessing you aren't quite as pessimistic now as you were a few weeks back on the ST forums then Certainly the second half of the chase is stil ltoo far out for me to really consider it, but I say once we get in 6-7 day time frame, seeing something so ominous has to be taken with more than a grain of salt. Either way I've decided to go into town and get some extra DV tapes tomorrow. Especially with my inability to copy to the laptop at the moment. I don't think 6 hours is anywhere near enough given those charts.

[pottyprof]

Nathan.. Don't forget the adult size Pampers..

*is still looking for a hidey hole in a suitcase*

[AudMun]

Nathan.. Don't forget the adult size Pampers.. B)

*is still looking for a hidey hole in a suitcase*

It has been recommended to me by an experienced member of the Net-Weather team B) that Tena Lady is very effective!

PP, perhaps you could persuade someone to take a second case?

Stewart

[Paul Sherman]

http://www.youtube.com/watch?v=0CGam7GohfQ

Here you go before we leave to wet your appetite, the last F5 In Moore (Oklahoma) May 3rd 1999

Paul S

[NL]

Jeez ... now thats scary!! The devastation that caused looked like an 'A' bomb had just been dropped!!

[pottyprof]

Saw that earlier Paul.. Janes just been watching, saying "Oh my GOD!!!!!" over and over again.. That is one stunning video.. Beat that!!

[Paul Sherman]

Storm Prediction Centre still not putting the 4-8 Outlook up at the Moment, all the Models know something is coming for the 4-6 May Timescale but have it ploughing through different parts of the Plains, (Even Canada)

So looks like Monday we could have a nice leisurely Chase as Storms should be firing in West & Central Texas, these will be Scattered Non Severe Storms with Hail & High winds the Primary Threat, so a nice Chase to cut our teeth with, always remembering that their Non Severe storms are the equivalent of the Uk's most amazing storm of the last decade, there is a Slight Risk on this day but it is way up in Illionois & Indiana, so unless one of the team has a Lear jet that one wont be Chaseable.

FROM THE SPC DAY 3 OUTLOOK

...PARTS OF THE SOUTHERN PLAINS...

SOUTHERN STREAM MID/UPPER LEVEL LOW WILL CONTINUE EWD ACROSS WRN

INTO CENTRAL TX DURING THE PERIOD. WIDELY SCATTERED THUNDERSTORMS

ARE EXPECTED TO CONTINUE WITH THIS FEATURE. MODELS INDICATE

POTENTIAL INSTABILITY TO AROUND 1000 J/KG TO SUPPORT A THREAT FOR

STRONG WINDS AND HAIL.

Paul Sherman

[Nick F]

Yes Paul, looks like there could be a few MCSs around on Monday and Tuesday, looks hot and humid with it aswell, may well gets some good night-time photography in with those anvil crawlers and spider lightning. The rest of the week looks uncertain for severe storms, atm GFS and ECM have the mid-level troughing aloft and moisture over Wern and Sern Plains but lack of wind shear with the jet streak way to the NW:

Thursday 00z ECM and GFS:

... howvever, the end of the week we should a jet streak move downstream from the Pacific across the Sern Rockies:

Nice deep trough over and jet streak Wern Plains by Saturday afternoon (Sun 00z), and a good dry line chase:

Think we may have to be patient for the SLGT AND MDT severe risks, maybe not until the end of the week when the jet streak moves in from the West.

[Paul Sherman]

As Nick says above, might not be until the end of the week before things get Interesting. Models starting to see-saw atm, even the 5th May not looking so set in stone now, with 3 models all differing in the evolution from Canada to the Central Plains. Nightmare a bit like our good old GFS In the Winter with endless promises of snow !!

Paul Sherman