Friday, January 31, 2020

Friday Night - Overcast. Low: 32-36

Saturday - High: 42-46 

Saturday Night - 32-36

Sunday - Sunny. High: 58-62

Monday -  Sunny. High: 58-62

Thanks to for the icons!

This weekend we will expect to see the sun after a week long of overcast skies.  We expect warmer temperatures and fair weather conditions as we come under the influence of a ridge.  This will persist at least until Monday. 
Forecasters: Balkissoon, Travis, Munley, Heaven, Ritter
Issued:  5:00pm: January 30, 2020

Technical Discussion (The nerdy stuff we are discussing in class)

To account for the change in temperatures from Friday to Sunday, we look at the 250 hPa Height and Wind Divergence.  Friday we observe that we are north of the jet which can account for the colder temperatures whilst on Sunday around 9Z, we sit south of the jet which are partly responsible for the warmer temperatures we are getting here in the mid-latitudes.  As the jet stream moves to the north of us on Saturday this accounts for the trough getting less amplified with time.

When we examine the 500 hPa vorticity, we notice on Sunday at 12Z, clockwise spin of winds which indicative of negative vorticity associated with the ridge.  On Sunday we observe from this map a zonal air flow.  As such since there is the presence of no dominant short waves, the atmosphere does not support baroclinic instability and ageostrophic flow.  We expect no precipitation on Sunday.  This is supported from the GFS Skew-T analysis which shows a dry rather than saturated sounding of the atmosphere.

From the 700 hPa relative humidity, however, on Friday night whilst we observe high values of relative humidity, there is no upward vertical motion which indicates no precipitation. 


No comments:

Post a Comment