The temperatures have tumbled and the rain has started to fall. It is the start of a cold and wet stretch that will carry on until the end of the month. It’s remarkable to remember we began October with highs in the 90s. We’ll be ending it with highs almost 50° colder.
The reason for this cold and wet mess of a forecast through Wednesday is a deep and slow-moving trough in the jet stream. It has already sent the cold front through the Tulsa area, but the upper-level winds are funneling ample moisture up and over that boundary into our area in several waves. The first of which is ongoing here on our Monday night. All of tonight’s rain will be light and over before temperatures dip to the critical freezing point northwest of Tulsa. A lull in the wet weather is expected Tuesday morning. In fact, the clouds may break enough to see a little sunshine early on. However, clouds will assuredly fill our skies by Tuesday afternoon as the next and biggest onslaught of rainfall begins. Below is a timeline of those chances.
By Tuesday night, rain is a guarantee. Temperatures will thankfully be warm enough to keep us out of any wintry weather, but cold enough to send you looking for some dry firewood. A few rumbles of thunder may even occur in the heavier downpours. Eventually, these showers will taper off Wednesday. Once the rain wraps up though, we could have another 2” of water or more in our rain gauges. That will further solidify our #2 position in wettest years to date for Tulsa. Below are projected rain totals. Minor river or stream flooding is possible.
There has been a lot of talk about the potential for snow midweek on the back side of this storm system. For now, it appears there will be enough separation of the moisture from the deeper cold air to really limit that threat for Green Country. However, it will be a close call. Our friends just up into Kansas may end up with an early season dusting. There might even be a window of freezing drizzle north of Tulsa, which would be far more dangerous. We cannot rule out seeing a snowflake or two around Tulsa Wednesday evening, but exactly the right combination of conditions must come together for this to occur this early in the season. If you want to see snow, head to northwest Oklahoma where they may have a second snowstorm this month! The map below shows the area most at risk for a little wintry weather Wednesday night.
That leads us to Halloween. Our average high for the holiday is 68°. This year, we’ll be lucky to break out of the lower 40s for a high. By evening, our teeth-chattering trick-or-treaters will need an extra layer or two on to stay warm with temperatures dropping back into the 30s. Fortunately, the winds will go light, but without much of a chance to acclimate, it could be a miserable candy hunt if you aren’t prepared. As of now, this is shaping up to be our 3rd coldest Halloween on record for Tulsa as shown below. The colder years happened to be when I was out trick-or-treating as a kid!
If we don’t hit freezing on Thursday morning, Friday morning will most likely be Tulsa’s first official freeze of the season. You’ll need to protect those plants late this week if you want to save them! Fortunately, the weather pattern into early November looks benign and warmer. Highs will return to the 60s later this weekend and dry weather likely takes hold for awhile. The projection into early November shows that temperatures will gradually warm, but remain mostly cooler than average.