We often think of spring as our only storm season, but we also have a storm season in the fall as well. Much like spring, fall is a transitional season. Those transitions from warm air to colder air often come with very strong storm systems brought to us by the jet stream.
At this time of year, the jet stream starts to drop south in response to colder air building at the North Pole. That increases our wind shear while we still have enough heat and moisture in place like springtime. Eventually we lose the necessary heat and moisture to fuel severe storms later in the season, but late September thru early November is the window where we see a slight increase in occurrences of tornadoes along with high winds and large hail.
October is the 5th most common months for tornadoes in Oklahoma, behind our spring months - according to the National Weather Service.
In fact, on this date last year, 7 tornadoes hit Oklahoma, including in Oklahoma City. Parts of the Tulsa metro area also received wind damage from this round of storms.
While the threat of tornadoes and high winds has its fall peak about now, the threat for large hail actually increases into November when colder air aloft becomes more prevalent – a key factor in hail formation in thunderstorms.
But as we know in Oklahoma, severe weather can happen from New Years to the 4th of July and any time in between if the right combination of heat, moisture and wind shear is found.
As is often the case in the fall, we get strong cold fronts that send our temperatures downward for the season. They can spark those severe storms along that boundary. To talk more about our specific severe weather threat, I’ll send it back to Stacia in the studio.