Friday, February 21, 2020

Friday Night - Clear.  Low: 22-26

Saturday -  Sunny. High: 50-54

Saturday Night -  Clear.  Low: 32-36

Sunday - Cloudy with chances of rain.  High: 46-50

Monday - Cloudy with chances of rain.  High: 44-48

Thanks to for the icons!

We warm up a bit for the beginning of the weekend, on Saturday, as we have no significant weather phenomenons taking place.  However, on Sunday due to the low pressure system moving in from the west, we are expecting some rainfall into Monday.
Forecasters: Balkissoon, Heaven, Travis, Munley
Issued:  5:00pm: February 21, 2020

Technical Discussion (The nerdy stuff we are discussing in class) 
From the WPC model diagnostics, the GFS blend was recommended for forecast analyses however the confidence given was below average. As such our map discussion will be done using products from the GFS run.  For our temperature values and the total precipitation amounts, the GEFS plumes were consulted.

Our first map that we looked at is the 250-hPa wind, heights and divergence.  For this weekend we sit underneath the jet.  We observe divergence aloft which implies that there is convergence taking place near the surface.  This convergence at the surface that rises is indicative of cyclonic motion in which there is the expectation of precipitation around Monday at 6Z. 

From the 500-hPa absolute vorticity map, at Monday at 0Z, we have a low pressure system coming in from the west of Missouri.  We observe with this feature, an counter-clockwise curvature of wind flow.  This system is more mature as it has a closed off cycle. 

From the 700-hPa Omega and RH, we observe that there is significant amount of moisture which is being fed from the Pacific.  We do have the combination of lift and saturation which is the reason behind our expectation of precipitation Sunday evening into Monday.  This is also supported from the GFS skew-T which shows both moisture and omega starting from Sunday at 21Z.  From our analysis of the 850-hPa winds, heights and temperatures, we can infer that the precipitation type is rainfall as we are expected to be consistently above freezing into the weekend and early week.  This is so as the warmer air is coming from the South-West.  We also observe the warming effects from looking at the thickness 1000-500-hPa map where the thickness contours are moving closer together.  From this map we observe CAA taking place as the counter-clockwise rotation of the cyclone is bringing in cold air from the north. 

The GEFS plumes have a total accumulation of rainfall in the amount of a little under one and a quarter inches. 

No comments:

Post a Comment