What You Need to Know About Winter Weather on the “Coq”

Coq Walloper - Nov 25 2015 - 003

[Note: Yellowhead Road & Bridge (Nicola) Ltd. took over the highway maintenance contract for Service Area 14 as of July 1, 2019].

We’ve heard from a few folks recently asking how they can travel the Coquihalla safely during the winter.  Apart from our usual recommendations for proper tires, checking DriveBC, keeping a full tank of gas and driving to conditions, we thought we could help travellers make better decisions around their travel by identifying some of the winter conditions found on the Coquihalla and explaining how they might impact travel. So, we asked our Weather Services Specialist, Simon Walker (who worked as an Avalanche Tech along the route for six years) to give us some insight.  Here’s what he had to say.

TranBC: What is the main thing you think people should know about weather on the Coquihalla during the winter?

The main thing that people should understand about the Coq (and the same applies to all the other mountain passes in BC to greater or lesser extents) is that, in certain circumstances, snowfall intensity and accumulation rates can be extreme – sometimes exceeding 10 cm per hour.  A great example of this type of intense accumulation occurred during February of 2014 when ten storm systems delivered a total of 294 cm of new snow over a period of 15 days! The traffic and road conditions resulting from this type of weather may be unpredictable – even with our maintenance crews out there throwing everything they’re got at it.

Don’t let that worry you though – our maintenance contractor for the route, has a plan. It’s called “the Coquihalla Protocol” and it comes into effect when more than 15-20 cm of snowfall over a 12 hour period (or freezing rain conditions) are predicted and its sole purpose is to make sure we maintain safe and uninterrupted travel through the corridor during heavy snowfall or other challenging weather event. If an incident does occur and you are stuck in a queue, it’s important to note that there are many marked avalanche paths along the route; please stay in your vehicle, as you may be stopped under one of these paths.  When closures do occur, ministry staff,  our contractors and emergency responders will be working as quickly as possible to manage the queue and clear traffic from avalanche areas. Traffic control personnel will be on site during these weather events, and travellers need to follow their instructions.

TranBC: So, drivers need to slow down, be patient and aware when conditions are like that. What other tips do you have to help them prepare for this kind of weather on the Coquihalla?

Simon:  If you look at the web cams and road reports on DriveBC when you leave Vancouver, you should check in on conditions again before leaving Hope, since things can change very quickly in the winter months. Also be aware that there are alternate routes: Hwy 3 (Allison Pass) from Hope to Princeton, and Hwy 1 (Fraser Canyon).  While both of these can have their moments of severe winter weather (and both are longer distances), they don’t get severe conditions nearly as often as the Coq.  There are also plenty of web cams and road reports for these routes to help drivers make the best decision before leaving Hope for the Interior, or before leaving Merritt if headed west.


You should also pay close attention to the Variable Speed Limit System in place along the route. These dynamic signs display the legal speed limit, which is updated as road and weather conditions change. Flashing lights installed above each variable speed limit sign are activated when a reduced speed limit is in effect.

Our Roadside Weather Stations collect information on weather and pavement conditions from strategic locations, and this data allows our Highway Maintenance Contractors to monitor current road conditions and provide the best response to these ever changing conditions.

TranBC: Any other insight, tips or advice you’d like to share?

Simon: Freeze – thaw cycles are common during the winter and especially during the shoulder seasons.  Take extra care when travelling in the late afternoon, early evening or when driving in and out of shaded sections of highway. Water and slush can quickly freeze solid then the sun stops shining on the road.  Roads exposed to sun will thaw more quickly than those in shade and areas shaded by north facing slopes are where black ice typically forms.

Coq restroom
These are the washrooms at the Coquihalla Summit rest area where accumulated new snow can exceed 10 m in a winter, resulting in a snow pack that can be more than 3 m deep on the ground. That is a lot of snow.                                    

So there you have it from one of our own avalanche and weather experts. A last reminder: don’t forget to pack warm clothing, boots and gloves and keep them inside your car. That way, if you’re delayed for any reason, you can stay safe and warm inside your vehicle.

Do you have a question about this or any other BC highway? Let us know in the comments below.

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