Good morning everyone. If you are sick of this recent heat the good news is you have one day to go until it breaks. The bad news is a period of wet weather is going to work its way into our region tonight through Thursday. This will be a dual threat from a cold front and then again from a low developing along the front. Lets take a look..
Cold front comes in late tonight/early morning with showers and a few rumbles of thunder possible..
A low pressure system then takes hold along the front on Thursday into Thursday night..
All models are in agreement with this. Image above is valid 8pm Thursday night. Bottom line, expect a rainy day tomorrow possibly into early Friday.
It is no secret that this is due to a approaching trough in the jet stream over our area. This is the opposite pattern that is currently giving us the hot weather..
In the short term this is great news once the rain clears out as we will have a few days of nice cool temps in the 70's and low 80's. However after early next week the warmer air will return although I expect it will not be as warm as the last two days..
You can see above the ridge develop over our area in the jet stream with the trough back east for middle of next week.
Shifting gears, lets take a current look at updated El Nino projections..
The above image is from the CFSv2 long term model. It shows the water temperature anomalies in the Nino 3.4 region. You can see currently it has it peaking around November over 2.5 degrees above normal (very intense). However, notice the crash afterwards as we head into winter. We should still have a strong El Nino for winter but it will be decreasing in magnitude. Other models are agreeing with this. For winter weather lovers I think that is decent news overall. Having an El Nino that is too strong makes for a more complicated winter forecast. We are all reminded of the Winter of 1998 which had one of highest El Ninos on record..
You can see the temps were well above average that winter. Now I will say the Pacific overall was different and the El Nino that year was more east based. Regardless, it is nice to see the models start to decrease our current El Nino just in time for winter.
Here are current Sea Surface Temps..
These were the Sea Surface Temps in Fall of 1997..
You can see the warm water in the El Nino region is more to the east in 1997 compared to currently and the pacific is warmer near California. That region will be key this winter, if the warm water currently gets too skinny then we could be talking mild. If it stays consistent and builds along with the el nino region staying more west, then we could be talking cold and stormy.
This among many other things is what I look at when making winter forecasts. Stay tuned for the forecast coming in October!
Thanks for reading.