 Welcome to the weather forecast for Longmont, the week beginning Wednesday, May 20th. I'm Chief Meteorologist John Insworth for Longmont Public Media. This Friday, we are at New Moon. We're going to slip into one of the drive-ins that are open or opening around the region. Not many of them. You'll have a New Moon, no problem with light from the sky. Looking at the weather, the big story is where this big ridge is. Right now, at the beginning of the week, it is right over and very close to Colorado. This gave us 92 degrees at the airport on Tuesday and took temperatures up into the upper 80s and 90s on the eastern plains on Wednesday. Big low off the western coast in California, big low in the upper Mississippi Valley. The big weather makers on both sides. You've heard about the heavy rainfall in Michigan and the flooding occurring there. This low in the west is creating a lot of rain and some snow in the higher elevations out west. The water vapor satellite image is reflecting that pattern. We have the low in the west and we have that low in the upper Ohio and Mississippi Valley. We have one of the ISO heights from the 500mm map, you can see it right there, to show you that the cloud features mirror this pattern pretty nicely and there's the big ridge up to the center of the nation. Also a ribbon of moisture coming up through here is what has kicked off some severe thunderstorms both on Tuesday and further east on Wednesday and up into Wyoming and Nebraska, South Dakota. Normal low temperature starts out at 40. The beginning of this 10 day period and rises a little bit. The normal high temperature starts out at about 72, 73 and rises a little bit. You can see at the beginning of this period we are well above normal. Night time temperature is way above normal with a cold front coming in on Wednesday. It will kick off some thunderstorms on the far northeast plains. We cool down to right inside down the low, a little cooler in the day, a little warmer at night just because there's still some moisture hanging around. At the beginning of the weekend we nudge just a touch above normal then a more significant system comes in and cools us down for the beginning of the week which is Memorial Day weekend. You can see the precipitation associated with that system and we're going to take a look now to see where it's coming from. Here's our moisture. This is the precipitable water. This is greener colors and even blue colors are the amount of water that could come out of the sky under ideal conditions, say under a thunderstorm doing its best. The mountains are a natural barrier so the Rockies don't allow the moisture over onto the western slopes easily in this scenario and we have moisture streaming down around the low across Texas and moisture coming out of the gulf and out of the Pacific up into the eastern plains and us. For Wednesday, it's a marginal chance of severe weather just east of I-25. I had to re-record this video because of a sound issue and it's actually a little further east than this graphic shows, just didn't have time to update it but it's still pretty dangerous up here on the Wyoming, South Dakota, Nebraska border Wednesday. Tons of tomatoes down here in the northeastern corner of Colorado and hail and high winds across all the eastern plains. For Thursday this hasn't changed much, it's a marginal chance of severe weather out here, a little slight area elevated down in Kansas and Panhandles of Oklahoma and Texas. We are probably on the backside of a dry line here so we might see some stuff pass but it won't go severe until it's further out on the plains. We're used to that, you look out east you see big storms billowing up as they then race away into the evening. Our next big change comes this weekend with the reversal pattern, we have the low and the trough in the east replaced by out ridge and we have the trough on the west coast coming in to the mountain west. So we're on the uphill side of a trough that means we get more lift, transport of moisture up from the South Pacific and we have cooler air coming in the loft to make the atmosphere more unstable. So that's where our weekend chances come right now, Saturday looks like the, I'm sorry Sunday afternoon and evening looks like the wettest period, we plan to do our front yard camping again, we've done it right around the 20th, third weekend of the month for three months in a row now and this is nicer, it's a three day weekend. So we probably won't have our fire out on the front lawn Sunday night, we may be in plain board games. How much rain? Well, not much. If you look at the five day precipitation total taking us into the beginning of the weekend, we have very minor amounts up here, a little heavier for some flay hill locations, a couple of thunderstorms that's making up down here, if you look out 10 days it's spotty still around. This is not an exact pattern at all, this is kind of gives you an idea of how far apart heavier thunderstorms will form, kind of the direction that the storms will travel coming out of the trough, the jet stream in the southwest and northeast so thunderstorms will trail in those directions. It's not a lot, unless you get a lucky thunderstorm, get right over, have, you know, not going to see a lot of water. So from Wednesday through Tuesday we start out probably breaking 90 on Wednesday, it's still on its way. We cool down with the first cold front into the 80s, the trough starts approaching, we drop into the 70s and then even into the 60s for Sunday, trough is here, we have our best chance of rain, maybe a few thunderstorms. For Memorial Day we start to warm up again, dry out and we go into the next work week above normal and dry. For more local news and for more frequent weather updates go to longmontobserver.org, this is about to become the Longmont leader but if you put in this link you'll be redirected for the foreseeable future, you won't miss a thing. So this has been your weather forecast for the week beginning May 20th, Chief Meteorologist John Linsworth for Longmont Public Media, keep looking up.