A cold Tuesday morning to you all.
For anyone reading the blog before sunrise (as these get posted at midnight), you may still have some time to bring in any potted or hanging plants you had out because of the warmer weather that has now changed. Temperatures will be dipping below freezing in many areas starting closer to 4am and staying there to as late as 9am or so. This is a dangerous spot for any flowers caught out of season (but the normally early bloomers should be able to handle it). Trees that bud unseasonably early are in the worst perdicament. We can track the temperatures and the frost below:
|Current Temperatures||Freeze Warnings (Pink)|
The freeze warnings in pink are the most dangerous for agriculture, but the frost warnings are also displayed in the olive green / yellowy color.
Temperatures will be warming up nicely after this morning, so expect some comfortable afternoons in the warm air that returns to the area. It's that 'advection' bit again. Warmer air will be arriving from the south, carried by those winds:
The red lines on this map indicate temperature lines of 10°C and 20°, and you can clearly see the influx of southerly air (meaning "winds out of the south") having an effect on pushing the wamr air northward-- and conversely the same could be said about colder air being pushed southward. This flip-flop of temperatures may be presented even more starkly by comparing the temperatures of the area to what they were 24-hours previously:
|GFS 24-hr Temp Change
(Mon AM to Tues AM)
|GFS 24-hr Temp Change
(Tues AM to Weds AM)
These colors demonstrate that from one day to the next we'll see morning temperatures today that are 15-degrees colder than Monday morning, and then Wednesday morning we'll be 20-25 degrees warmer than where we were Tuesday. A lot of ups and downs there, but the afternoon temperatures will not have the same sort of flux (in the 60s both days).
Looking ahead to Wednesday, we're still monitoring the arriving showers, and at this point it does look like thunder may play a role, though the story is a little different depending on which model you look at:
|GFS Wednesday 8pm||WRF Wednesday 8pm
The WRF indicates a little weaker precipitation intensity (and often that co-relates to a weaker thunderstorm prevalence). At this point, I'm leaning toward the GFS more enhanced look, but our nice little period of sunshine does appear to go on hiatus Wednesday no matter what you're looking at.
--- Longer range tangent (wonky)--- (feel free to skip)
Right now this is the only model calling for this (the GFS), and you should always view the long range GFS and Euro models with this sort of lens:
Kay (Tommy Lee Jones) says at one point in the movie Men In Black: "There's always an Arquillian Battle Cruiser or a Corillian Death Ray, or an intergalactic plauge that is about to wipe out all life on this miserable little planet, and the only way these people can get on with their happy lives is that they DON'T KNOW ABOUT IT!"
I suppose one of the ancillary purposes of this blog is to "let you know about it" :-) but I gotta tell ya, these things show up on the longer range models all the time, and verify much less frequently. But anyway take a look at this for next Monday night:
Click on the image for a pop-up of a larger image.
Okay, since you're curious, I'd like to pop up 4 different graphics examining the same time-frame (I have shown each of these individually at times on this blog). The top left image is the vorticity map, and clearly there's a ton to discuss there, but for now we'll say there's a lot of storm energy available there. The top right image is the combination of surface pressure (highs and lows) and "atmospheric thickness". Now if you want more detail with either one of these things, let me know. To briefly explain, the sea level pressure map helps us identify areas of high pressure (nice weather) and low pressure (nasty weather). The higher the highs and lower the lows, the stronger the weather of that type is. The "Average" pressure on this earth is a little over 1010 "milibars" or "mb" ... Taking a look at that map, the low pressure value of the center of that storm is somewhere in the 980s. To provide context, the 970s have been associated with hurricanes. The "Atmospheric Thickness" bit is just another way of measuring temperature. With gases, the warmer the gas, the less dense they become in a given volume, so it follows that a thicker column of air will come to be associated with a higher average temperature. As a point of reference, the "540" line (which is dashed red) is typically associated with conditions that are cold enough for snow(!) The bottom left map is relative humidity at the cloud level. Clearly there is a lot of phasing between all the elements as displayed on the model (high humidity--green wrapped up in the storm, with low humidity-- brown around the outside). The bottom-right is the precipitation map, and there's a lot going on there too.
This will be a fun exercise we'll return to over the next few days, as almost invariably the models will knock this down into something much less note-worthy, and if they don't, well that will be quite something to plow across the country early next week. :-)
---End Wonky Longer-Range Tangent---
All right, on a sunny day, not as many tracker tools are critical, so we can save on eyeball strain by just highlighting the radars. If anything changes, I'll post some updates.
Update 9:30am - The Storm Prediction Center has placed parts of our area under a "Slight Risk" for severe weather on Wednesday, specifically to time with the arrival of the front. There will have to be a phasing of the heating of the day with the positioning of the front and the best storm juice available in order to get these types of storms cranking. At this point, the best thinking is that there will be a narrow window for this type of thing to occur, and it's here:
Currently the possibility for gusty winds accompanying these storms is what is driving this 'slight risk' determination. This is something we'll be keeping an eye on, particularly with the next blog post that will be up at midnight tonight.
|Regional Radar/Satellite with Warnings Tracking||
Keep warm this morning at the bus-stop, but dress in layers, because this afternoon is going to be just so nice :-)