Simpson LAX Forecast

This is the forecast for the Los Angeles Airport LAX and some of the surround areas.

To begin I looked at the normal highs and lows for LAX for today, this I got from the NWS website. I then looked at the current conditions at the airport and found that it was mostly cloudy at the airport but when I looked at the radar I could see that the northern part of the city was experiencing showers. As seen below, provided by wuderground.com:

Then I looked at the big picture. I looked at the weather portal, http://home.comcast.net/~dwpusey/portal.html . I looked at the 12Z models on all at once comparing what was going on in the big picture. From this I found that there was a trough and low that was affecting California and producing those showers.This can be see in the image below.

I then saw that the low quickly moved out of the area and that a ridge was going to set up over LAX area and that it looked to remain dry for the rest of the weekend and into the next week. There is a low pressure system that will affect the Northwest Pacific but it doesn’t look like it will be affecting southern California. This looked consistent over all of the models that I compared including WRF, GFS, ECMWF, UKMET, and CMC.

I then looked closer at the ending time of the showers over the area. With this I used a cross section that you can find in the weather portal and looked at the temperature, wind shift and speed, and also the precipitation. I also consulted the meteogram for a reference, this data was found at http://wxp.eas.purdue.edu/wrfdata/wxbrief/. Both showed the showers rapping up by dinner time and moving into the mountains. It did look like the showers could linger in the foothills till later tonight but for the most part would be clearing out. When the showers will end the wind looks to picking up significantly and remain breezy for the next 24 hours.This can be seen in the three images below.

From all my data that I collect I was able to make a 7-Day forecast for the LAX area.

Forecast:

Friday: Mostly cloudy with showers in the morning and later afternoon. Showers should end around dinner time. Winds increasing to 15mph to 20mph throughout the day.

Saturday: Remaining breezy for most of the day. Clouds should also decrease through the day. Other than a lingering shower in the mountains, the rest of the area should remain dry. Expect high temperatures in the low 60’s.

Sunday: A high pressure system looks to be building in and winds will be shifting to an easterly flow. This will keep the LAX area dry and warmer than it has been in the last couple of days. Expect temperatures in the mid 60’s.

Monday: Temperatures continuing to increase, with a high temperature in the upper 60’s. Dry and mostly sunny conditions expected.

Tuesday: Expect high temperatures in the low 70’s. The high pressure in place will keep the area dry and warm.

Wednesday: Warm temperatures expected again on Wednesday with temperatures in the low 70’s. Dry Conditions also expected.

Thursday: Some disturbance in the Northwestern Pacific will break down the ridge late Wednesday and early Thursday this will decrease temperatures somewhat but I still suspect that temperatures will be in the mid to upper 60’s.

Verification:

For the Short-term there was a lingering shower at 6pm local time but after that it became dry, like the forecast said for LAX. The shower activity for a place a little farther inland, like Riverside, CA saw showers wrapping up at about 7pm. There were some isolated storms later about 125 miles south of LAX that had some damaging winds but the showers that went though LAX just produced about a half an inch of rain. The showers and snow showers did get stuck up in the mountains and dissipated on Saturday, but the precipitation did move out of the valley by dinner time and the valley did remain dry through the weekend and up until Today the 17th. As far as the temperature part of the forecast they look pretty good. They are always in the range that was stated. All the models did very well with this forecast. Also I checked today for the next two days and it looks like models are consistent to what they were saying last week.