Cooler air keeps trying to move in

Issued: Monday, Oct. 19, 2015 · Covering: Oct. 21 – Oct. 28, 2015

It’s becoming more and more evident we are moving into the transition phase between fall and winter, as the weather models have a tougher time figuring out the forecast. The first part of last issue’s forecast was pretty good, but the timing of the systems then started to slip.

This forecast period will begin with a trough of low pressure sliding off into Ontario, with western regions seeing mostly sunshine and eastern regions struggling with clouds. Temperatures will briefly cool down behind this trough before warming back up into the mid-teens on Thursday, as an upper ridge builds in. This upper ridge will be quickly pushed off to the east as an area of low pressure develops over the central states and quickly zips to the northeast on Friday. This low will bring clouds and showers to most regions on Friday, with some significant rainfall possible. Luckily, it looks like this low will move through pretty fast and clearing skies should move in early on Saturday. Temperatures will cool down behind this low under a northerly flow, with highs on Saturday and Sunday expected to be in the +8 to +10 C range.

A large area of low pressure off the Pacific coast will help to generate an area of low pressure over Alberta on Monday. This low is currently forecast to travel across the central Prairies on Tuesday and Wednesday. Winds will become southerly ahead of the system, helping to boost temperatures back into the +13 to +15 C range by Tuesday. It looks like most of the precipitation from this system should stay to our north, but a more southerly track is possible. Much cooler air will work into the back side of this system and there is a chance we could see a little bit of snow as the system pulls out. Highs for the second half of next week are forecast to be in the +3 to +5 C range.

Usual temperature range for this period: Highs, +3 to +15 C; lows, -6 to +3 C. Probability of precipitation falling as snow: 20 per cent.

About the author

Co-operator contributor

Daniel Bezte

Daniel Bezte is a teacher by profession with a BA (Hon.) in geography, specializing in climatology, from the U of W. He operates a computerized weather station near Birds Hill Park.



Stories from our other publications