Tuesday, April 22, 2014

Earth Day chase

I suppose it was fitting to storm chase on Earth Day even if the setup wasn't conducive to seeing much. A cold front crossing the mountains created a lee trough that fired up some cells that didn't amount to anything given a paucity of moisture (DP's only near 50).  However this was a great opportunity to shake out the equipment and streaming setup before any serious weather arrived.

I rolled eastward first to Burnt Chimney to assess the situation and found myself underneath a developing convective line. Continuing eastward to Gretna I rechecked radar and visually scanned the western horizon before deciding to drop south to Chatham. A reasonably developed storm was headed in that direction and I stopped on Rte 57 east of town to watch, live stream, and take a photo or two:

As I awaited the approach of this storm I noticed on radar a couple of discrete cells west of this line segment and a bit further south. I thus motored east to the other side of the White Oak Mountain ridgeline to stay ahead of the rain and then dove south. I wound up at a truck stop / warehouse complex on Rte 29 just north of Blairs and stopped to live stream again, this time communicating via text and voice with WDBJ's Robin Reed. The live stream quality was good but there really wasn't much to see:

I finished the chase by verifying some strong outflow winds south of Danville that actually showed on radar. After these cells swept on by I had a dry trip homeward.

Monday, April 21, 2014

Couple chase chances this week

I use "chase" very loosely with respect to tomorrow when a cold front pushes across the Old Dominion. GFS and NAM still disagree a bit on timing as well as the amount of instability so I'm not expecting a lot. It will be a chance to iron out a few more wrinkles in this year's chase gear, including a live stream via Severe Studios. (I'll only have the live stream up if there is something worth seeing...not a fan of watching someone's feed while they drive down a highway.) Looks like tomorrow morning will involve poring over the short range models for timing and target location.

Friday, however, could be a different story but there are still a number of model runs to go (this morning's 12Z GFS is a bit more pessimistic than earlier solutions). It's that time of year when it's prudent to keep an eye on the models as the week progresses so as to not miss a chase opportunity!

Saturday, April 19, 2014

Reprise of an April 2005 chase

    Given that SDS is rampant this month while awaiting the spring severe season to kick off I thought I'd repost this northern Virginia chase account from 2005:


                                                              April 2 2005 Hailstorms

     April chasing opened with a bang on the second day of the month when the Storm Prediction Center outlooked eastern Virginia for a slight risk of severe storms and a 5% tornado probability, a significant figure of merit for the Mid-Atlantic. The first action of the day was focused on a warm front lifting northward as I chased east of Fredericksburg during the late morning, catching only a glimpse of a small shelf cloud. After lunch I rendezvoused with my son in Thornburg where we parked his car and consolidated our gear into mine. From there we rolled west and then south on Virginia Route 208 underneath a low overcast, hoping that an approaching upper level pool of cold air would provide the impetus for some strong updrafts.

     We covered only five miles of two lane macadam before breaking into brilliant sunshine, immediately glimpsing hard-knuckled convection boiling up to the south in response to the aforementioned cold pool. Our interception course led us across Lake Anna into Louisa county, and somewhere south of the metropolis of Mineral we gloried in our first pea-sized hailfall of the day. Continuing east and then south to stay with the most active cells we enthusiastically enjoyed three more hailfalls, one of which occurred with the sun shining and thus enabling the following cool photo:
Photo by Nathan White

     In an attempt to keep up with the best convection we looped through the town of Louisa while tracking a feature that appeared at first to be a ragged wall cloud but was really another shelf cloud from an outflow-dominant storm. Not having mobile internet and thus without radar access we then miscalculated the convective line’s movement, thinking it was headed due north when it was quickly steaming northeastward. As a result we wound up out of position to catch up with a very interesting lowering at the back of the southernmost cell. However, we were afforded a great view of the overall storm structure and witnessed multiple rainbows while thoroughly enjoying ourselves.
Photo by Nathan White

     The 5% tornado probability didn't verify for us as we saw no funnels and heard no tornado reports but we really didn't care. This early April chase proved to be one of the bright spots of an otherwise abysmal 2005 Virginia chase season. Serendipities come when they come!

Tuesday, April 15, 2014

No chase but a clearly defined frontal passage

I chose not to chase today given that the best setup for doing so is well east of where I would consider going. But...I was out and about the Roanoke valley this morning and got to experience the cold frontal passage. Here's what it looked like ~10:40 a.m. looking southwestward from the Hollins vicinity:

FROPA was very obvious as the wind suddenly swapped around from southerly to northwesterly and the thermometer plunged while I was outside my vehicle snapping photos. Now the question is how long the current pattern will take to reset and provide the next chasing opportunity. It may be a couple of weeks from now which would mean April is pretty much over for Virginia chasing.

Monday, April 14, 2014

Tax Day chase?

April 15th is notorious as Tax Day but could it also be a chase day in 2014? I haven't been impressed with the model solutions for my chase region altho' the SPC is calling for a 5% chance of severe storms over the far western Piedmont of Virginia:

I'm concerned that the heavy rainfall forecast ahead of the approaching cold front will squelch convection, impair visibility, and prevent discrete storms west of the I-85 corridor. And since I'm not willing to go to that far east (too far, too populated, too many trees, etc.) without a REALLY good setup this isn't tempting me much.

Of course if tomorrow's RAP and HRRR runs look good all bets are off...