York Region Snow Day Predictor & Calculator
Will YRDSB close tomorrow?
The York Region District School Board covers nine municipalities stretching from urban Markham and Vaughan in the south to rural Georgina on Lake Simcoe in the north — 190 schools and 130,000 students closing simultaneously when YRDSB calls a snow day. That geographic spread is everything. Markham and Richmond Hill roads may look completely manageable while rural King Township and Georgina routes are unsafe. YRDSB makes one decision for the entire board — rural northern routes set the threshold.
This predictor is calibrated to YRDSB's actual closure behaviour — the board covers more geographic and climate variation than almost any other Ontario board, and a flat snowfall threshold misses the northern exposure entirely. Check the probability score above for tonight's YRDSB snow day forecast for all nine York Region municipalities.
YRDSB Announcement Window
By 6:00 AM
Check at 9pm for an early read and again at 5am for the final pre-announcement probability. YRDSB announces by 6:00 AM — covers all nine York Region municipalities from Vaughan and Markham to Georgina and King.
York Region District School Board — YRDSB Snow Day
YRDSB and YCDSB both serve York Region — both almost always align on closure decisions.
York Region District School Board
YRDSB covers all nine York Region municipalities — Markham, Richmond Hill, Vaughan, Aurora, Newmarket, King, East Gwillimbury, Georgina, and Whitchurch-Stouffville. Rural King Township and Georgina routes drive the closure threshold.
York Catholic District School Board
YCDSB almost always aligns with YRDSB — both boards monitor the same road conditions across York Region. Always verify at ycdsb.ca or @YorkCatholic directly.
YRDSB Snow Day — Markham, Richmond Hill, Vaughan, Newmarket & Aurora
One YRDSB decision closes schools across all nine municipalities simultaneously.
Markham Snow Day Predictor
Markham falls under YRDSB. Southern York Region — Markham roads are typically among the best conditions in the board during a storm. But YRDSB closes for the worst route across all 190 schools. When YRDSB closes, all Markham schools close even if local conditions look manageable.
Richmond Hill Snow Day Predictor
Richmond Hill falls under YRDSB. Located in central York Region, Richmond Hill sits between the urban south and rural north — it typically sees moderate conditions relative to the board's geographic spread. When YRDSB calls a snow day, all Richmond Hill schools close simultaneously.
Vaughan Snow Day Predictor
Vaughan falls under YRDSB. Located in western York Region bordering King Township, Vaughan sits closer to rural northern routes than Markham. King City and Kleinburg areas within Vaughan are more exposed to winter conditions than central Vaughan. One YRDSB decision closes all Vaughan schools.
Newmarket Snow Day Predictor
Newmarket falls under YRDSB. Located in central-northern York Region, Newmarket typically receives more snowfall than southern municipalities like Markham. Aurora and Newmarket together form the central spine of YRDSB territory — these areas often reflect the board-wide average conditions most accurately.
Aurora Snow Day Predictor
Aurora falls under YRDSB alongside Newmarket. Aurora sits just south of Newmarket in central York Region — its elevation and position make it slightly more exposed to winter conditions than Markham or Richmond Hill. Aurora schools close with all other YRDSB schools when a closure is called.
King Township & Georgina
King Township and Georgina are the rural northern anchor of YRDSB territory. Georgina sits on Lake Simcoe and receives lake-effect enhancement. King Township routes through Schomberg, Nobleton, and Pottageville are the most exposed to winter conditions in YRDSB — and they drive the board-wide closure decision for all 190 schools.
One predictor covers all nine York Region municipalities: Whether you are in Markham, Richmond Hill, Vaughan, Aurora, Newmarket, King, East Gwillimbury, Georgina, or Whitchurch-Stouffville — this YRDSB snow day predictor applies to your school. YRDSB makes one decision for all 190 schools.
Verify Here When the Announcement Drops
Always verify from official sources — predictions update hourly but announcements are final.
York Region Snow Day Pattern — North vs South
York Region's geographic spread creates dramatically different snow conditions across the board — and rural northern routes always drive the YRDSB closure decision.
Markham · Richmond Hill · Vaughan
Southern York Region municipalities sit close to Toronto and benefit from the same urban infrastructure and plowing priority. Markham and Richmond Hill typically receive similar snowfall to north Toronto. These areas often have manageable road conditions at 5am when northern York Region routes are already unsafe. When YRDSB closes based on northern conditions, southern parents often look out their window and wonder why school is cancelled.
King Township · Georgina · East Gwillimbury
Northern York Region is a completely different weather environment. Georgina sits on Lake Simcoe and receives lake-effect enhancement. King Township routes through Schomberg and Nobleton cover rolling Canadian Shield terrain with no urban plowing infrastructure. East Gwillimbury rural routes along Yonge Street north of Newmarket face exposure similar to Simcoe County. These routes regularly see 5 to 10cm more accumulation than Markham during Alberta clipper events.
Why Markham parents need this predictor more than they think: If you live in Markham or Richmond Hill and your Markham roads look fine at 6am, you might assume school is open — but STYR may have already cancelled King Township and Georgina routes at 4am, which triggers the YRDSB board-wide closure. This predictor accounts for the entire YRDSB geographic footprint — not just your local conditions.
YRDSB Snow Day History — York Region School Closures
What actually closed York Region schools — and the north-south gap that drives the decisions.
Major Alberta clipper deposited 25cm across York Region. YRDSB closed all 190 schools. Northern Georgina and East Gwillimbury received 30cm while southern Markham received 20cm — a 10cm gap across the same board. Highway 404 and Highway 400 reduced to one lane.
Winter storm deposited 22cm across York Region overnight. YRDSB and YCDSB closed. Rural King Township routes declared unsafe by 3am. Newmarket and Aurora received heavier accumulation than Markham and Richmond Hill — northern routes drove the decision.
Arctic outbreak with wind chill reaching -38°C across York Region. YRDSB closed for cold-day safety — one of the coldest days on record. All nine municipalities affected simultaneously regardless of snowfall totals.
Is It a Snow Day Today in York Region? — YRDSB Status
Check the probability gauge at the top of this page for today's YRDSB snow day status. The predictor updates every 30 minutes from live Environment Canada data. If you are checking after 6:00 AM on a storm morning, go directly to yrdsb.ca or @YRDSB on Twitter for the official announcement — YRDSB announces by 6:00 AM. YCDSB announces simultaneously at ycdsb.ca.
Will YRDSB Have a Snow Day Tomorrow?
Check at 9pm tonight for the best early read on tomorrow's YRDSB snow day probability for York Region. A score above 70% at 9pm warrants backup childcare arrangements — especially for Markham and Richmond Hill parents whose local roads may look fine while northern routes are already deteriorating. Check again at 5am, when STYR assessors are driving King Township and Georgina routes and the probability score is most accurate before the 6:00 AM YRDSB announcement.
York Region Snow Day Predictor — What Are the Chances?
The York Region snow day calculator scores nine variables against YRDSB's documented closure behaviour — overnight snowfall accumulation weighted differently for northern versus southern municipalities, precipitation type, wind speed, active Environment Canada warnings, rural route exposure across King Township and Georgina, storm timing, and YRDSB's historical closure multiplier. The result is a percentage reflecting the actual chance YRDSB closes tomorrow — not a generic GTA forecast.
York Region Road Conditions
Highway 404 · Highway 400 · Yonge Street · King Township Roads · Georgina County Roads
Highway 404 north through Markham toward Newmarket, Highway 400 through Vaughan toward King Township, and rural King Township and Georgina county roads are the key corridors monitored by STYR and YRDSB assessors. When King Township and Georgina routes show closure warnings on 511on.ca alongside an active Environment Canada winter storm warning, a full YRDSB school closure is very likely regardless of what Markham or Richmond Hill conditions look like.
What Do York Region Parents Think?
Will YRDSB close tomorrow? Cast your vote — resets daily at midnight.
Community vote — not a prediction. Check the probability gauge above for the algorithm-based score.
GTA & Nearby Cities — Snow Day Predictor
YRDSB Snow Day FAQ — York Region School Closures
York Region questions about YRDSB and YCDSB school closure decisions.
What school board is YRDSB?
YRDSB is the York Region District School Board — the public school board serving all nine York Region municipalities: Markham, Richmond Hill, Vaughan, Aurora, Newmarket, King, East Gwillimbury, Georgina, and Whitchurch-Stouffville. YRDSB has 190 schools and 130,000 students.
What time does YRDSB announce school closures?
YRDSB announces by 6:00 AM. The fastest sources are Twitter @YRDSB and yrdsb.ca. 680 News 680 AM and CTV Toronto also broadcast closure announcements from 6:00 AM.
Does YCDSB close when YRDSB closes?
Almost always. York Catholic District School Board and YRDSB monitor the same road conditions across all nine York Region municipalities and typically announce within minutes of each other. Always verify at ycdsb.ca or @YorkCatholic directly.
Does YRDSB cover Markham, Richmond Hill and Vaughan?
Yes — YRDSB covers all nine York Region municipalities including Markham, Richmond Hill, Vaughan, Aurora, Newmarket, King, East Gwillimbury, Georgina, and Whitchurch-Stouffville. When YRDSB closes, all 190 schools across all nine municipalities close simultaneously.
Why does YRDSB close when Markham roads look fine?
YRDSB covers rural King Township and Georgina in northern York Region where roads receive lower plowing priority. A storm that leaves Markham and Richmond Hill manageable can make rural King Township and Georgina routes unsafe. YRDSB makes one closure decision for all 190 schools — rural northern route conditions set the threshold, not urban southern conditions.
What triggers a YRDSB school closure?
Overnight snowfall above 15cm and rural route conditions in King Township and Georgina are the primary triggers. When STYR cancels buses region-wide, YRDSB almost always closes all 190 schools. Wind chill below -35°C also triggers cold-day closures across York Region.