Winter Weather Discussion for December 14 – 15, 2007.
*Potentially Significant Snowfall*
– Winter Storm Watch north of a line from Hollis to Lawton to Tulsa. Snow is likely to start in the watch area Friday afternoon and continue through Saturday morning. There is some potential for freezing rain and sleet on the southern edge of the watch. The watch will likely be upgraded to a heavy snow warning for parts of northwest and north-central Oklahoma where 8-10 inches of snow may fall.
– State EOC remains on 24 hour activation.
– Around 300,000 meters remain without power, in Oklahoma.
Very complex and potentially significant winter weather event shaping for the region tomorrow and Saturday. 00z NAM appears to have caught on to a variety of issues 1) the fact that it was only 32F today in OKC, 2) that the system isn't as progressive as progged, and 3) the amount of moisture available. AFDOUN is a great read this evening and I certainly agree.
For this forecast I'll stick with what is expected and note that the 00z NAM has converged on the GFS's solution from the past few days. As such the most significant snowfall is expected in northwest and north-central Oklahoma with 8-10 inches possible. As you go south the snowfall accumulation will decrease but even in OKC at least 4 inches is possible. Ground temperatures are around 40F across much of the area, so I expect very little loss due to melting. The main thing that might limit accumulations at OKC and points south could be warm air at 925mb and around the surface. However, I continue to think the NAM is still too warm tomorrow for OKC. The ice pack remains and is not going anywhere fast, the cloud cover also isn't helping. The good news in this forecast is that the ice storm area probably won't get hit again. The bad news is that already thin resources will be taxed even more.
The NAM QPF panel for Saturday night back 24 hours shows a precip max around Enid and Ponca City of 0.75 inches to 1 inch water equivalent. Surrounding that is a 0.50 to 0.75 from Watonga to Tulsa. I'd be interested to see what Tulsa NWS does after screwing with their WSW today. Anyway, The 0.25 to 0.50 area covers much of the state. The area from Mangum to Guthrie to Bartlesville will likely be all snow. Areas immediately south MAY start as rain, turn to freezing rain/sleet and then quickly to snow.
Model runs from the 06z and 12z will be closely reviewed given potential for a significant event.
For more information, weather news, weather blog, and chase summaries go to http://www.hook-echo.com.