Frontal Analysis and Distortion over Snake River Plain

Objectives:

Gain experience in frontal analysis and the use of non-conventional observational (e.g., MesoWest) data over regions of complex terrain

To improve knowledge of frontal evolution over regions of complex terrain.

Part 1:
Steenburgh and Blazek (2001) described the topographic distortion of a low-level cold front over the Snake River Plain and central Idaho Mountains. Their frontal analyses at 0600 UTC and 1200 UTC 3 December 1998 are presented below.

Using observations from the MesoWest historical database, determine the time of frontal passage at the following stations, which were located ahead of the front at 1200 UTC 3 December 1998:

Twin Falls (KTWF) Meteogram Text
Stanley (KSNT) Meteogram Text
Richfield (RIC) Meteogram Text
Jerome (KJER) Meteogram Text
Minidoka (MIN) Meteogram Text
Craters of the Moon (CRA) Meteogram Text
Pocatello (KPIH) Meteogram Text
Aberdeen (ABE) Meteogram Text
Arco (ARC) Meteogram Text
Black Foot (FOO) Meteogram Text
Kettle Butte (KET) Meteogram Text
Hamer (HAM) Meteogram Text

The locations of these sites are given in the figure below.

You might find the following surface plots to be useful (click on a station for a time series).

Part 2: Answer the following questions:

At what sites is the front well defined?
At what sites is it difficult to determine the time of frontal passage?
Where do the temperature/wind/pressure changes accompanying frontal passage differ from that normally expected?
How does the character of the frontal passage vary across and along the Snake River Plain?

Part 3: Print out the igures below and analyze the frontal positions at 1500 and 1800 UTC 3 December 1998.

1500 UTC 4 December

1800 UTC 4 December