diff --git a/cmd/service-splitarea/main.go b/cmd/service-splitarea/main.go
index aeb6ff4..c79f716 100644
--- a/cmd/service-splitarea/main.go
+++ b/cmd/service-splitarea/main.go
@@ -20,7 +20,7 @@ import (
 	"weatherstation/internal/database"
 )
 
-// Service that, at each hour, processes previous hour's :30 radar tile for z/y/x,
+// Service that, at hh:45 each hour, processes current hour's :30 radar tile for z/y/x,
 // splits a user region into 0.1° grid, averages dBZ (linear domain), fetches Open‑Meteo
 // hourly variables at grid centers, and writes a CSV.
 
@@ -177,7 +177,7 @@ func fetchMeteo(ctx context.Context, client *http.Client, lon, lat float64, utcH
 	return &mv, nil
 }
 
-// job executes the split+augment for a specific local time (CST) and fixed minute=30 of previous hour.
+// job executes the split+augment for a specific local time (CST) and fixed minute=30 of the same hour.
 func job(ctx context.Context, z, y, x int, bounds string, tzOffset int, outDir string, runAt time.Time) error {
 	loc, _ := time.LoadLocation("Asia/Shanghai")
 	if loc == nil {
@@ -185,8 +185,8 @@ func job(ctx context.Context, z, y, x int, bounds string, tzOffset int, outDir s
 	}
 	runAt = runAt.In(loc)
 
-	// Previous hour's :30
-	targetLocal := runAt.Truncate(time.Hour).Add(-1 * time.Hour).Add(30 * time.Minute)
+	// Current hour's :30
+	targetLocal := runAt.Truncate(time.Hour).Add(30 * time.Minute)
 
 	// Fetch tile
 	rec, err := getRadarTileAt(ctx, z, y, x, targetLocal)
@@ -398,14 +398,17 @@ func main() {
 		return
 	}
 
-	// Hourly scheduler: run at each hour boundary for previous hour :30
+	// Scheduler: run hourly at hh:45 for current hour's :30 radar tile
 	loc, _ := time.LoadLocation("Asia/Shanghai")
 	if loc == nil {
 		loc = time.FixedZone("CST", 8*3600)
 	}
 	for {
 		now := time.Now().In(loc)
-		runAt := now.Truncate(time.Hour).Add(time.Hour) // next hour
+		runAt := now.Truncate(time.Hour).Add(45 * time.Minute)
+		if now.After(runAt) {
+			runAt = runAt.Add(time.Hour)
+		}
 		time.Sleep(time.Until(runAt))
 		// execute
 		if err := job(ctx, *z, *y, *x, *b, *tzOffset, *outDir, runAt); err != nil {