The State College Bubble Effect

2008 June 16 Severe Weather Summary from WFO State College

The picture says it all...severe weather does not happen in State College. We are literally in the proverbial polygon doughnut hole (center of image; black dot is approximate location of the city). In all fairness, we were in a severe thunderstorm warning 20080426, but its a rare species here in Happy Valley. Perhaps some research on the State College Bubble Effect is needed...

Severe Weather Continues...

18z OAX sounding looks fairly good, if you want to see rotating storms. Nice backed low level flow on sounding and across eastern NE/western IA will support tornadoes, although there is a fair bit of cloud cover over this area. Storms have fired in central NE ahead of clearing (sun has destabilized the air mass) and are moving mainly northerly. Storm motions are quite fast (at least one storm is supposedly moving 65 mph).

Strong, damaging winds look like the main threat along with flash flooding as storms transverse the Midwest this afternoon/evening.

2034Z
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SPC has just upgraded their outlook for Thursday, June 5, to a high risk. Similar to last Thursday, this high risk is over the same region and a bit larger. All modes of severe weather are likely with the emphasis currently on damaging winds. Also, heavy rains has caused more flooding over saturated grounds and it will not take much today to cause flash flooding. More will be posted later and I'll be once again watching how things develop this afternoon and evening as I am off.

I can not recall such an active season of severe weather in at least the last 5 years. Last night, a supercell developed south of Omaha, NE and moved northeast before making a hard right turn down US Hwy 34. It was an isolated supercell, which means that it's inflow of warm, moist air into the storm was unobstructed. Hence, it sustained itself for several hours (at least 4 hours if I recall correctly). Several Iowa State students and faculty along with a few other storm chasers followed the storm as it moved due east around 15 to 20 miles per hour. Several tornadoes have been reported from last evening, but little information is known beyond that at this time.

1311Z

Moderate Risk: Southern Pennsylvania

It remained fairly quiet in State College today, but that's not to say no severe weather occurred. I did not venture out as the threat never materialized and obligations would have made for a late departure.

A severe thunderstorm warning was issued for the northern part of the county, but from the text it sounds like the cell fell apart before it even got past the county border. Not even a rain drop fell (at least on my head or windshield) since early this morning.

In past years, May 31 has seen its fair share of significant weather in the eastern part of the US. The hype around May 31 comes from 23 years ago, when a major tornado outbreak occurred over PA, NY, OH, including Pennsylvania's only F5.

01/0321Z
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Tornado Watch has been canceled for southern Pennsylvania.
1846Z
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Not much time to post...a moderate risk was out earlier for eastern PA, but has since been shifted to the southern tier of counties. A 10% tornado probability exists over this region, but large hail and damaging winds will also be possibilities this afternoon. Currently, a band of showers and thunderstorms is moving from west to east over the southern counties, which is under a tornado watch.

In northern and western PA, cumulus clouds have billowed as sunshine was able to break through the cloud deck earlier this morning. Showers have just begun to erupt east of Bradford, PA. This looks to be the line one line that has a chance at State College.

Farther west in southern Ontario, Canada, Ohio and Michigan, a broken line of storms (most are in southern Ontario about to cross Lake Erie) will push their way into PA late this afternoon and evening. The storms will diminish as they cross the cool waters of Erie, but reintensify over land as they march towards Penn State.

Likely will be a no-go for chasing as I have obligations until 6ish, but may try to find a spot to observe the storms. We'll see.

May 29, 2008 High Risk - Eastern Nebraska/Western Iowa

The high risk has been downgraded to a moderate risk this evening. While the potential for tornadoes and hail still exist, the primary threat will be damaging wind in extreme eastern Nebraska, many parts of Iowa, northern Missouri and northeastern Kansas.

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A High Risk of severe weather is expected across portions of eastern Nebraska and western Iowa including (but not limited to) the cities of...Storm Lake...Milford...Spirit Lake...Estherville...Omaha...Lincoln...Sioux City. The threat for large hail, damaging winds, and potentially long-tracked tornadoes exists for Thursday, May 29. The above image highlights those areas...red indicates a 30% chance of tornadoes, blue, 15%, brown 10%, light brown 5% and green 2%.

I'll be monitoring the situation from Pennsylvania and provide updates as is warranted.

Last night's discussion...
As [Jayson] Prentice noted [on ISU forums], and WRF/AVN cloud products/MOS station plots indicate, could be quite a bit of cloud cover over Iowa and even eastern NE. It will be interesting to see how well things recover in temperatures and dewpoints department after tonight's convection.

WRF/GFS say Td's will recover to near 70 in parts of SE NE...I find that hard to believe considering they are in the low/mid-50s, but I know that there will be good low-level jet tonight.

Anyway, Norfolk-Randloph-Neligh triangle would be fine I think. The flow looks southerly here, but could be locally backed. South of I80, I think it will be more SWerly (as WRF depicts (GFS is sourtherly)).

This triangle target is northeast of the CAPE max on a gradient and also on a CIN gradient (WRF at 18Z has CIN ~100/GFS is 150ish). Where the WRF/GFS places the CAPE, 700mb temps are around 12C...which is on the fence for breaking/not breaking the cap.

GFS pops convection west of there (triangle target) around 21z...WRF is hard to figure out what's going on, but it appears like the WRF kicks something up around 21z as well because of differential heating boundary from tonight's storms/tomorrow's clouds...then bounces back to better forcing near front/dryline.

Deju Vu x3? Update

Evening Update

Yes, I know it's after midnight so it's technically not evening. Anyway, thunder and lightning (big deal here in State College) occurred this evening between 8:00 and 8:30. The power even flickered on and off once (glad I have a UPS) and there was at least one lightning strike that was fairly close! Okay, yes, pathetic by Midwest standards, but just incredible for Pennsylvania.

Here are a few screen grabs from this evening (with storm tracks!)
Cell near State College that brought a couple of heavy downpours to my roof and some "decent" thunder and lightning.

Tornado warning in upstate New York heading toward Utica. A trained spotter viewed a wall cloud and a funnel lowering near Sylvan Beach; however, at this time it is not included in SPC's storm reports. Velocity data didn't look overly impressive so perhaps a gustnado/sheriffnado/landspout or a funnel that never reached the ground.

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I'm currently at work and just sent the NY City Early and IHT pages off...boy that sounds familiar (last Saturday). However, it is true. The sun this day, though, has been only been out for a little bit compared to last week, so instability will be low to nil. Hence, "See Text" outlook with 5% hail and wind threats. Grams (ISU M.S. 2005) did today's outlook. I believe this is his 2nd time soloing the outlook, and I'm glad it involves PA! Just wished he could have worked in some rotating storms...

17z mesoanalysis shows no CAPE of any type in Pennsylvania. The closest, and weak at 250-500J/kg, is located in southern Ontario on the north side of Lake Erie and in eastern Michigan. Hope for more sunshine seems dim as latest satellite image shows a rather extensive patch of clouds, with some breaks, that will likely be over us the rest of the day. So unlikely we'll see much in the way of instability here.

12z PIT sounding has winds at the surface out of the southwest, and then from 900mb-100mb west or west-northwest winds. In other words, linear flow means no rotating storms, although with cold air aloft, places that do see sun and get some instability will have a chance at some strong winds as winds mix down.

While there is a "risk" of severe weather today, I didn't even contemplate a chase, although I did bring my charged camera to work in case something worthwhile did go, I could at least get some pictures from work.

Deju Vu x3?

Once again, and for the 3rd time in 4 weeks, Pennsylvania may have a rare glimpse with severe weather on yet another Saturday (April 26, May 10, and perhaps May 17?) Since I work tomorrow, I won't entertain the idea of chasing and it doesn't look like an outstanding event to chase. Perhaps I'll charge the gear up and take some pictures late in the day.

Possible Chase Update

I ended up staying in State College.

The SPC 20Z update didn't change from previous versions. While there was some instability and that's where some of the stronger storms developed, nothing could really become surface based. Thus, storms were fairly linear in nature. I didn't leave work until around 7 (could have been out by 6 if I wanted) as I finished up some webpage enhancements for work.

Possible Chase Today

I'm currently at work and just sent the NY City Early and IHT pages off, but I've been watching the sun start to come out here in State College since around noon/1PM local time. Thus, some instability is developing over the area. 18z SPC mesoanaylsis has 250J/kg of CAPE to the west of Centre county and line of storms is currently approaching State College from Cambria and Clearfield counties. SPC has this area (of State College) and west of here in 2% tornado...not great, but for PA that's like a moderate risk.

Earlier I thought I may get off by around 4, but I'm now closing for the day which means I'll be here until 6ish. It's probably a good thing so that I don't chase on a less than exceptional day...gas is 3.59 (was 3.65 a few days ago). Behind the initial line of storms appears to be a secondary line trying to get its act together. I'll put more money on small hail and some baseline severe wind damage.

Will await 4PM SPC update...

VEISHEA webcam images

Here are some webcam shots from VEISHEA 2008. I had to work, but I streamed the parade while I did various tasks for The Times. And you all thought I actually worked...

The early part of the parade with a firetruck (center) and a space shuttle float (left). Check out that snow too!!!

The good ol' VEISHEA balloon.

Another firetruck from the webcam ontop of Agronomy Hall. Good job Daryl.

Another balloon float.
Firetruck in center of the screen is the same one on the previous image from Agronomy!

Happy VEISHEA!

Good Saturday morning to everybody. It's shortly after 8AM EDT and it's VEISHEA back at Iowa State University. A glorious morning with a current temperature (7AM) of 32 degrees F, with light snow! Very exciting. Here are several webcams to check out the action.

West Lawn looking south from Parks Library
Iowa State Memorial Union Fountain
IEM Campus Shot

A little bit later today (Saturday, the 13th only) Daryl's automated scripts will place a movie online from the IEM camera. Go to Daily Movies, then select Ames from the "camera", then lapse is "sunrise" to watch the snow accumulate?

Just in case you aren't up early enough, here are some images.






Meanwhile, in Happy Valley, it is a beautiful 52 degrees and sunny, with an expected high near 60. Don't worry though, the cold front will come through and make it cooler in the mid-40s the next couple of days before roaring back into the middle 60s by the midweek.

Time for work though.