adds flask caching

app.py

@@ -2,9 +2,19 @@ from flask import Flask, render_template, jsonify, request
 from utils.weather import get_today_snowfall
 from utils.geocode import get_city_name
 from config import MAX_SNOW_INCHES
+from flask_caching import Cache
 
 app = Flask(__name__)
 
+# Cache config: 10-minute default timeout
+cache = Cache(app, config={"CACHE_TYPE": "SimpleCache", "CACHE_DEFAULT_TIMEOUT": 600})
+
+@cache.memoize(600)  # cache each request for 10 minutes
+def get_snowfall_for_location(lat, lon):
+    inches, snowing, tz_name = get_today_snowfall(lat, lon)
+    city_name = get_city_name(lat, lon)
+    return inches, snowing, tz_name, city_name
+
 @app.route("/")
 def index():
     return render_template("index.html")
@@ -16,8 +26,7 @@ def snowfall_api():
     if lat is None or lon is None:
         return jsonify({"error": "Missing lat/lon"}), 400
 
-    inches, snowing, tz_name = get_today_snowfall(lat, lon)
-    city_name = get_city_name(lat, lon)
+    inches, snowing, tz_name, city_name = get_snowfall_for_location(lat, lon)
 
     from datetime import datetime
     import pytz