Good Evening Everyone,
Based on all the analyses I put together, here’s what I found… The pattern over the US has been very mild to warm one for the Central and Eastern US. Severe weather continued to be significant for the central and eastern portions of the US. For areas in the Pacific Northwest and the Lower Mississippi Valley the pattern has brought excessive amount of precipitation. Therefore, these two locations have a higher risk for flooding since the ground is saturated. These are some of the key themes that you will see from the images below. So, sit back, grab a snack and beverage and check out images below.
Upper Air Trends
Here are some of the basics I have on this analyses. The 500mb anomaly map is an analysis that’s taking a look from 18,000 feet above the ground. These anomaly maps help identify tendencies how ridges (high pressure) and troughs (low pressure formed. Think of ridges as regions of stable weather (i.e., dry, cold or hot regions) and troughs as regions of active weather (i.e., wet and stormy). The shades of yellow to dark reds indicate ridging while shades of blue indicate troughs. Once you see the ridges and troughs, you can sketch the placement of the jet stream. Although, that can be done by looking at 250mb or 300mb maps. Those are analyses that meteorologists will look for in jet stream placement.
This month the upper air pattern has favored record a Pacific Northwest trough and significant ridging over the Eastern US. In terms of the sensible weather, record breaking warmth took place over the central and eastern US. In addition, this month an active Pacific Jet has helped promote severe weather, especially over the Southern US. Also, quite a few damaging tornadoes.
– 500mb Upper Air Height Anomaly Map (Thu, Mar 1 – Fri, Mar 23)
The next two maps, continued to show how the upper air pattern favored the jet stream farther to the north near the US Canada border. Occasionally, jet would buckle and bring in brief cold shots, but that would be it. As you look at the Winter 2011-12 upper air map, you can see how mild of a look it had. Even the Polar Vortex, which is a strong upper level low that directs the cold air, really didn’t budge. Just so many factors against a really cold and snowy winter for the US. Overseas in Russia and Europe, the pattern favored a severe winter pattern. Significant blocking kept that trough in place over Europe, hence the rough winter season.
– 500mb Upper Air Height Anomaly Map (Wed, Feb 1 – Wed, Feb 29)
– 500mb Upper Air Height Anomaly Map (Tue, Dec 20 – Thu, Fri 23)
Surface, Upper Air, and Storm Report Trends
Check out these images below. Note the correlation on what we saw with the upper maps and now the surface maps. For the Storm Prediction Center maps, I sketched in the jet stream. Notice how busy its been for severe weather. One of the key players has been the effect on La Nina. La Nina typically has been one where in the Spring, the Pacific Jet can be so strong and dominant. Its a big player for severe weather. For the severe weather the southern half of the US has been a hot spot for severe weather, thanks in part to an active Pacific Jet Stream. The conditions so far this year have been very ripe for severe weather, especially tornadoes.
– Sea Level Pressure Anomaly Map (Wed, Feb 1 – Wed, Feb 29)
– SPC Storm Report with Jet Stream Overlay (Wed, Feb 1 – Wed, Feb 29)
– Sea Level Pressure Anomaly Map (Thu, Mar 1 – Fri, Mar 23)
Just check out the numerous reports for March. So far this month, 200 tornadoes..
– SPC Storm Report with Jet Stream Overlay (Thu, Mar 1 – Fri, Mar 23)
Temperatures Trends
The analysis below are anomaly maps. I really like to use these analyses to show me a signal or trend over the past several weeks and months. What you will see from the maps I put together was how above average its been for the past couple months.
The theme here has been the record warmth. The past week really shows the peak of the mild to warm weather. Please note, that I didn’t get a chance to accurately type in the correct number of record high temperatures and high minimum temperatures. Let’s just say there were many records broken..
– Record Warmth (Sun, Mar 18 – Sun, Mar 25)
– Record Cold (Sun, Mar 18 – Sun, Mar 25)
The next two maps really how the depth of the overall above average temperatures for high and lows.
– 30 Day Mean Anomalies (Wed, Feb 22, 2011 – Fri, Mar 23, 2012)
– 90 Day Mean Anomalies (Sat, Dec 24 – Fri, Mar 23)
Precipitation Trends
Finally, the last batch of images will show you precipitation trends. Notice here and the prior sections, I like to work from the past week to several months back. You’ll notice I like to look over the River and Lake Flood stages. If the models are forecasting more rain for these areas, the high the risk for flooding. Just one of the many analyses you can take a look at….
– Record Rainfall and Snowfall Reports (Sun, Mar 18 – Sun, Mar 25)
Portions of the Lower Mississippi Valley really have had a lot of rainfall and its definitely an area of a higher risk for flooding.
– River and Lake Flood Stages (Sun, Mar 25)
– 30 Day Mean Total Anomalies (Thu, Feb 23 – Fri, Mar 23)
– 90 Day Mean Total Anomalies (Sun, Dec 25 – Fri, Mar 23)
Two key developments in here is how dry its getting over in California and East Coast. It looks like for folks in Georgia north to New Jersey running behind. You can almost tell where the storm track has been of late.. The Pacific Northwest and down near Texas and Ohio Valley.
– Year Mean Total Anomalies (Sun, Jan 1 – Fri, Mar 23, 2012)
The worst areas have drought conditions continue to be over extreme southeast Louisiana, Georgia, and Florida.
– Precip Need to End Drought (Week Ending March 17)
Please feel free to check out my website at www.ezweather.com. My site has an abundant amount of weather links on Forecasts, Climate Data, Model Data, Discussion and Resources. It is a site that contains vast amount of information. So, definitely check it out.