LONG RANGE FORECAST THROUGH THE MIDDLE OF OCTOBER - 9/23/2019
Be sure to see the 3 month and winter forecasts down below
September is another bridge month. It takes us from summer to fall. It can also see the first cool temperatures arrive. Typically in September, temps are in the 80s and 90s at the beginning of the month, but drop sharply to the 60s and 70s by the end of the month. The all time record for September is 110 which happened in 1943. Average rainfall for Medford in September is just over a half an inch, mostly due to thunderstorm activity at the beginning of the month. In many years September can be dry. Wet storms can arrive at the end of September bringing rain and snow for the mountains. Meteorological fall started on the 1st of September, and seasonal fall arrived on Monday the 23rd.
Looking at what we can expect through the middle of the October......the pattern we have been seeing is going to hold. Expect it remain cold and wet. In fact, we are already seeing the kind of conditions that would be more typical for late October going into November than the middle to end of September. But, we have been in fall really since the early part of September. Where temps would normally be in the 70s to the 80s west of the Cascades and 70s east of the Cascades, it is now expected we will be looking at a temps running 15 to 20 degrees below average over most of the region, except the coast. So as you can see, significantly cooler than typical. Overnight lows will be cooler than average as well. But, not nearly as much as the daytime highs. Why? Cloud cover, When you are seeing conditions more typical late October into early November, that means there is going to be more cloud cover.
And with clouds.....you get rain and snow. We are expected to be above average for both rain and snow through the middle of October. The very wet pattern is expected to continue. Medford has already had over twice as much rain in September as would be average. This is expected to continue. And, this is going to be the case region wide. The data is very clear about this. We will also see snow developing in the mountains. Snow levels will be low for late September and October. It looks like areas abouve 4000 feet will be seeing snow fall. The accumulating snow will be most likely above 5000 feet. It is not clear yet if this is the start of the real snowpack that will build over the winter. We could see snowfall, and then that snow could melt off. In a typical fall, that is what we see early on. But, with temps expected to be so far below average, this could also be the start of the bigger snowpacks to come through the winter.
VERY LONG RANGE OUTLOOKS FALL 2019 AND WINTER 2019 - 2020
Multiple sources are now indicating that we are headed for another very good winter with plenty of rain and snow. The very big outlier now is NOAA. They are insisting that will be warm and dry once again as they have every year for the last 5 years. I am no longer using them for any long range forecasting as they have not been accurate with it for over 4 years now.
First, let's look at the two most accurate sources we have for long range prediction of winter weather. This would be the almanacs. There are two. The Old Farmers Almanac, and Farmers Almanac. Tru to the name, the Old Farmers has been around the longest. In terms of accuracy they have a very long history of getting it right more often than wrong. Farmers Almanac has more of a miss rate.....but to the credit, they were the ONLY long range source that got our winter right last year. And, being that the overall pattern has not changed that much, I am going to give a lot of creedence to what they say. So here are their predictions;
Old Famers Alamanc:
Accuweather did finally get their forecast for the winter out. It is something of an outlier compared to the two above. In fact, it comes closer to resembling what NOAA has forecast. And again. NOAA is saying sdry and warm. Just as they have for the past 5 winters. Accuweather sees us being mild for the winter. Both in terms of temps and also precipitation. So when compared to the two sources above and what we see down below from the State of Oregon, that is not aligning at all. Based on what we have already seen so far it really does not align. But, that is what long range forecasting is about. It is really an estimate of what you think is going to happen. Based on the other sources we have here, it seems like Accuweather's take on temps could be closer to right. But, predicting a mild winter for precipitation is looking to be a stretch. But, we shall see what comes to pass.
The state of Oregon also does offer long range prediction. And typically speaking, they do a good job of being accurate on at least one phase. There are two phases by the way. Precipitation, and Temperature. The State of Oregon does not release more than a 3 month outlook. So here is what they have for October through December. In this case, basically fall. On the left hand side is temperature. They believe that we will be about 3 to 5 degrees above average for temps for October through December. The right hand side is precipitation. They expect most of the state to be right about normal to slightly above except for that green swath. That swath runs from Southwestern Deschutes County down into Klamath County, and Western Lake County. They predict 115 percent of normal precipitation in that green swath.
I do think the the last part of what they put up is very noteworthy. That lines up with Old Farmers projections as well.