Retired senior lecturer in the Department of Meteorology at Penn State, where he was lead faculty for PSU's online certificate in forecasting.
By: 24hourprof, 8:00 PM GMT on December 02, 2014
Media reports on Pacific storms like the one currently off the West Coast of the United States drives me crazy. Just this morning, a nationally known TV weathercaster pointed at the plume of clouds funneling toward California and said, "the jet stream is driving in lots and lots of moisture." Good grief!
First, this feature is the subtropical jet stream...typically located near 200 mb (about 12 kilometers up...see 00Z GFS model analysis from last even...
Updated: 8:02 PM GMT on December 02, 2014
By: 24hourprof, 4:39 PM GMT on November 16, 2014
In the aftermath of the very intense, 924-mb extratropical low-pressure system in the Bering Sea, I read several historical accounts regarding the low's place in weather records. A scientific reference in one of the blogs caught my eye, but for dubious reasons.
For reference, the lowest central pressure of Hurricane Andrew (1992) was 922 millibars. Despite the potential of a similar pressure at its peak, wind speeds in extratropical cyclones such as the...
Updated: 4:55 PM GMT on December 01, 2014
By: 24hourprof, 3:08 PM GMT on November 15, 2014
This morning, there were two bands of bay-effect precipitation over Chesapeake and Delaware Bays (one band over each bay). Below is a loop of infrared satellite images spanning from 1015 UTC to 1345 UTC, which shows the two convective bands of clouds.
A loop of infrared satellite images from 1015 UTC to 1345 UTC on Saturday, November 15, 2014.
The bands tend to align themselves with the mean-layer wind in the lower half of the troposphe...
Updated: 4:12 PM GMT on November 15, 2014
By: 24hourprof, 10:06 PM GMT on November 08, 2014
I had a dental procedure last week to fix resorption in one of my teeth. I first had a root canal, followed by surgery that exposed the root of the tooth, where my endodontist had to fill two holes caused by the resorption. The aftermath has not been pleasant.
The pain from my surgery was bad enough. Then I heard the media once again predicting the approach of the "polar vortex" from Canada and the associated Arctic air arriving over the contiguous sta...
Updated: 10:23 PM GMT on November 19, 2014
By: 24hourprof, 2:42 PM GMT on August 16, 2014
As a gradually weakening Hurricane Iselle bore down on Hawaii in early August, I was watching a television analysis of the storm, which included a color-enhanced water-vapor image of the Pacific basin similar to the standard image (below) at 21Z on August 6. The weathercaster correctly pointed out the "dry air" on Iselle's western flank (and that the ingestion of dry air was helping to disrupt Iselle).
The 21Z standard water-vapor image over t...
Updated: 11:58 PM GMT on August 16, 2014