STORM OF THE CENTURY… of the Week

March 3-7, 2001

Why This Storm is Famous:Pulling a “Bolaris”

SLP, 12hr Precip(in) and 850mb Winds(knts)

Overview3/3 00Z: Air mass boundary

3/4 00Z: Closed surface low forms3/4 12Z-3/5 12 Z: Development of surface and upper lows3/4 12Z-3/6 00Z : Examination of Cyclogenesis through temp advection, Stretching3/6 00Z: Mature Stage forecasted snow for Philly3/6 12 Z: The beginning of the end

Comparison of Forecast and Validation

03/03 00 UTC: Warm Front in Right Entrance of Jet

03/04 00Z: Closed Surface Low Forms

3/04 12 Z

3/05 00 Z

3/05 12 Z

3/04 12Z Temp advection with height = cyclogenesis

12 hours later

3/04 12Z: Lower temp advection = change in upper Rossby waves

24 Hours Later….

3/05 12Z: Positive Feedback

3/04 12Z: Temp advection at surface = advection of thickness

3/05 12Z: 300mb Rossby waves enhanced=more vorticity=strengthening of low= more T advection

= Positive Feedback

Stretching Term:

3/04 00Z

3/04 12Z

3/05 00Z

Increase negative omega with

height

Stretching of air

Increase Vorticity

Intensify Low

3/06 00Z: Mature Stage

3/06 12 Z:

3/07 00 Z:

500mb Relative Humidity and

Surface Temperature

The beginning of the end

Were Warnings Justified?

3/06 00Z: Forecast vs Validation of 300mb Heights

3/06 00Z: Forecast vs Validation of SLP

Comparison of Forecasted and Validated 300mb heights and SLP

300mb heights3/06 00Z

SLP3/06 00Z

3/05 12Z Forecast Thickness and SLP

3/05 12Z ValidatedThickness and SLP

3/05 12 Z Comparison of Thickness and SLP

3/06 00Z Comparison of Trenberth Forcing

Validated

Forecasted

One Last look at totals: