Bill Schintler
EF4
A period of light snowfall will bring an inch or two of accumulation to eastern Iowa Friday afternoon. Looking ahead, a dramatic warm-up is on the way towards the end of the weekend. On Monday, very gusty south winds will help push temperatures into the low 50’s. Finally, a major winter storm will affect parts of the upper-Midwest next Friday although it is too early to have any confidence in the track or timing of the system. Below are specific forecasts for locations in Eastern IA:
Cedar Rapids:
Light snow will begin at 1:45 PM Friday and taper to flurries by 7 PM with a total accumulation of 1.6 inches.
Iowa City:
Light snow will begin at 1:30 PM Friday and taper to flurries by 7 PM with a total accumulation of 0.9 inches.
Marengo:
Light snow will begin at 1:15 PM Friday and taper to flurries by 6 PM with a total accumulation of 1.1 inches.
Synopsis:
SFC high-pressure is sliding E of the region ATTM with light WSW winds increasing in its wake. Strong WAA is occurring at the nose of a 35kt LLJ from NEB through the Dakotas. The water vapor loop indicates high clouds spreading E of this feature. Forecast soundings suggest CI to reach the area by 13Z followed by a lowering of the clouds during the morning hours.
Discussion:
WRN CONUS ridge will begin to flatten, which will push the thermal ridge now over the ERN Rockies EWD while a couple of S/WVs lift to the E and provide lift. Latest MDL trends have trended back toward more moisture advection and isentropic up-glide along the 280-290 SFCS as impressive H7-H8 WAA develops Friday morning. The FCST QPF has also trended NWD. Following the onset of QPF, a few hours will be needed to saturate the column. This leaves two hours of moderate snow aided by forcing from a compact vort-max and associated mid-level QG forcing centered in and around the dendritic growth zone in NCNTRL IA. The SREF bridges the differences between the GFS and NAM, and suggests 1 inch of snowfall along I-80 in ERN IA, and a few inches north of US-20.
- bill
[FONT="]9:00 PM CST, 01/24/08[/FONT]
Cedar Rapids:
Light snow will begin at 1:45 PM Friday and taper to flurries by 7 PM with a total accumulation of 1.6 inches.
Iowa City:
Light snow will begin at 1:30 PM Friday and taper to flurries by 7 PM with a total accumulation of 0.9 inches.
Marengo:
Light snow will begin at 1:15 PM Friday and taper to flurries by 6 PM with a total accumulation of 1.1 inches.
Synopsis:
SFC high-pressure is sliding E of the region ATTM with light WSW winds increasing in its wake. Strong WAA is occurring at the nose of a 35kt LLJ from NEB through the Dakotas. The water vapor loop indicates high clouds spreading E of this feature. Forecast soundings suggest CI to reach the area by 13Z followed by a lowering of the clouds during the morning hours.
Discussion:
WRN CONUS ridge will begin to flatten, which will push the thermal ridge now over the ERN Rockies EWD while a couple of S/WVs lift to the E and provide lift. Latest MDL trends have trended back toward more moisture advection and isentropic up-glide along the 280-290 SFCS as impressive H7-H8 WAA develops Friday morning. The FCST QPF has also trended NWD. Following the onset of QPF, a few hours will be needed to saturate the column. This leaves two hours of moderate snow aided by forcing from a compact vort-max and associated mid-level QG forcing centered in and around the dendritic growth zone in NCNTRL IA. The SREF bridges the differences between the GFS and NAM, and suggests 1 inch of snowfall along I-80 in ERN IA, and a few inches north of US-20.
- bill
[FONT="]9:00 PM CST, 01/24/08[/FONT]
