diff --git a/Readme.md b/Readme.md
index a5ca104b..e2a80e6e 100644
--- a/Readme.md
+++ b/Readme.md
@@ -179,7 +179,7 @@ __incomingForm.encoding = 'utf-8'__
 
 The encoding to use for incoming form fields.
 
-__incomingForm.uploadDir = process.env.TMP || '/tmp' || process.cwd()__
+__incomingForm.uploadDir = process.env.TMP || process.env.TMPDIR || process.env.TEMP || '/tmp' || process.cwd()__
 
 The directory for placing file uploads in. You can move them later on using
 `fs.rename()`. The default directory is picked at module load time depending on
diff --git a/lib/incoming_form.js b/lib/incoming_form.js
index 060eac29..e2e54f26 100644
--- a/lib/incoming_form.js
+++ b/lib/incoming_form.js
@@ -10,12 +10,12 @@ var util = require('./util'),
     EventEmitter = require('events').EventEmitter,
     Stream = require('stream').Stream;
 
-function IncomingForm(opts) {  
+function IncomingForm(opts) {
   if (!(this instanceof IncomingForm)) return new IncomingForm;
   EventEmitter.call(this);
 
   opts=opts||{};
-  
+
   this.error = null;
   this.ended = false;
 
@@ -38,7 +38,13 @@ util.inherits(IncomingForm, EventEmitter);
 exports.IncomingForm = IncomingForm;
 
 IncomingForm.UPLOAD_DIR = (function() {
-  var dirs = [process.env.TMP, '/tmp', process.cwd()];
+  var dirs = [
+    process.env.TMP,
+    process.env.TMPDIR,
+    process.env.TEMP,
+    '/tmp',
+    process.cwd()
+  ];
   for (var i = 0; i < dirs.length; i++) {
     var dir = dirs[i];
     var isDirectory = false;
diff --git a/test/legacy/simple/test-incoming-form.js b/test/legacy/simple/test-incoming-form.js
index 84de439e..b388c411 100644
--- a/test/legacy/simple/test-incoming-form.js
+++ b/test/legacy/simple/test-incoming-form.js
@@ -29,7 +29,12 @@ test(function constructor() {
   assert.strictEqual(form.type, null);
   assert.strictEqual(form.headers, null);
   assert.strictEqual(form.keepExtensions, false);
-  assert.strictEqual(form.uploadDir, '/tmp');
+  // Can't assume dir === '/tmp' for portability
+  // assert.strictEqual(form.uploadDir, '/tmp');
+  // Make sure it is a directory instead
+  assert.doesNotThrow(function () {
+    assert(fs.statSync(form.uploadDir).isDirectory());
+  });
   assert.strictEqual(form.encoding, 'utf-8');
   assert.strictEqual(form.bytesReceived, null);
   assert.strictEqual(form.bytesExpected, null);